67 research outputs found

    Large Number Discrimination by Mosquitofish

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    Background: Recent studies have demonstrated that fish display rudimentary numerical abilities similar to those observed in mammals and birds. The mechanisms underlying the discrimination of small quantities (,4) were recently investigated while, to date, no study has examined the discrimination of large numerosities in fish. Methodology/Principal Findings: Subjects were trained to discriminate between two sets of small geometric figures using social reinforcement. In the first experiment mosquitofish were required to discriminate 4 from 8 objects with or without experimental control of the continuous variables that co-vary with number (area, space, density, total luminance). Results showed that fish can use the sole numerical information to compare quantities but that they preferentially use cumulative surface area as a proxy of the number when this information is available. A second experiment investigated the influence of the total number of elements to discriminate large quantities. Fish proved to be able to discriminate up to 100 vs. 200 objects, without showing any significant decrease in accuracy compared with the 4 vs. 8 discrimination. The third experiment investigated the influence of the ratio between the numerosities. Performance was found to decrease when decreasing the numerical distance. Fish were able to discriminate numbers when ratios were 1:2 or 2:3 but not when the ratio was 3:4. The performance of a sample of undergraduate students, tested non-verbally using the same sets of stimuli, largely overlapped that of fish

    Canine leishmaniosis in the Italian northeastern Alps: A survey to assess serological prevalence in dogs and distribution of phlebotomine sand flies in the Autonomous Province of Bolzano - South Tyrol, Italy

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    Abstract The Autonomous Province of Bolzano-South Tyrol (APB), located in the northernmost territory of the Italian eastern Alps, is still considered non-endemic for canine leishmaniosis (CanL) despite clinical cases being observed and a competent Leishmania infantum vector (Phlebotomus perniciosus) having been recorded since 2008. A serological survey of leishmaniosis among a randomly-selected subpopulation of registered owned dogs was carried in 2018, followed by entomological investigations performed in 2019 and driven by canine survey results. A total of 457 resident dogs from all over the APB territory were examined through IFAT for antibodies against L.infantum, of which 63 (13.8%) tested positive. Thirty-five seropositive cases (7.7%) were considered autochthonous to APB, i.e. dogs born and lived in the province, or imported dogs with no travel history in the past 5 years. Most of these animals showed an antibody titre at the threshold level of 1:40, suggesting a low degree of parasite transmission/contacts. In 2 autochthonous cases with moderately high IFAT titre, the infection was confirmed by nested-PCR in peripheral blood. Thirty-one georeferenced sites were monitored for sand flies by means of interception (sticky papers) and attraction (CDC miniature light traps) collection devices. Traps were set during summer approximately on monthly basis, and extended up to October for positive sites. Only 2 sites were found positive for a total of 317 phlebotomine specimens collected by sticky traps, which included a previously known P. perniciosus-endemic site near Bolzano town. Sergentomyia minuta was by far the most prevalent (98.1%) and the only recorded sand fly species in the most northerly Italian site ever investigated (Coldrano municipality in Venosta valley). For the first time, Leishmania serology and n-PCR positive dogs autochthonous to APB were identified, however the spread of sand flies competent for L. infantum transmission could not be demonstrated in several places where endemic seropositive cases were recorded. APB can be considered a territory of low CanL endemicity, however awareness and continuous monitoring are needed to detect changes in the epidemiological status of the zoonosis

    Prevalence of SARS-CoV-2 positivity in infants with bronchiolitis: a multicentre international study

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    Background Bronchiolitis is the leading acute respiratory tract infection in infants during the winter season. Since the beginning of the SARS-CoV-2 pandemic, a reduction in the number of bronchiolitis diagnoses has been registered. Objective The present study aimed to describe the incidence and clinical features of bronchiolitis during the 2020-2021 winter season in a large cohort of children in Europe and Israel, and to clarify the role of SARS-CoV-2. Setting, patients, interventions We conducted a multicentre observational cross-sectional study in 23 paediatric emergency departments in Europe and Israel. Clinical and demographic data about all the cases of infants diagnosed with bronchiolitis from 1 October 2020 to 30 April 2021 were collected. For each enrolled patient, diagnostic tests, treatments and outcomes were reported. Main outcome measures The main outcome was the prevalence of SARS-CoV-2-positive bronchiolitis. Results Three hundred and fourteen infants received a diagnosis of bronchiolitis during the study period. Among 535 infants who tested positive for SARS-CoV-2, 16 (3%) had bronchiolitis. Median age, male sex predominance, weight, history of prematurity and presence of comorbidities did not differ between the SARS-CoV-2-positive and SARS-CoV-2-negative groups. Rhinovirus was the most common involved pathogen, while respiratory syncytial virus (RSV) was detected in one case. SARS-CoV-2 bronchiolitis had a mild clinical course, with one patient receiving oxygen supplementation and none requiring paediatric or neonatal intensive care unit admission. Conclusions During the SARS-CoV-2 pandemic, a marked decrease in the number of bronchiolitis diagnoses and the disappearance of the RSV winter epidemic were observed. SARS-CoV-2-related bronchiolitis was rare and mostly displayed a mild clinical course.During the SARS-CoV-2 pandemic, very few infants with SARS-CoV-2 had bronchiolitis and mostly displayed a mild clinical course. Overall there was a marked decrease in bronchiolitis cases, indeed the RSV winter epidemic did not occur

    Evidence for Two Numerical Systems That Are Similar in Humans and Guppies

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    Background: Humans and non-human animals share an approximate non-verbal system for representing and comparing numerosities that has no upper limit and for which accuracy is dependent on the numerical ratio. Current evidence indicates that the mechanism for keeping track of individual objects can also be used for numerical purposes; if so, its accuracy will be independent of numerical ratio, but its capacity is limited to the number of items that can be tracked, about four. There is, however, growing controversy as to whether two separate number systems are present in other vertebrate species. Methodology/Principal Findings: In this study, we compared the ability of undergraduate students and guppies to discriminate the same numerical ratios, both within and beyond the small number range. In both students and fish the performance was ratio-independent for the numbers 1–4, while it steadily increased with numerical distance when larger numbers were presented. Conclusions/Significance: Our results suggest that two distinct systems underlie quantity discrimination in both humans and fish, implying that the building blocks of uniquely human mathematical abilities may be evolutionarily ancient, datin

    Ontogeny of Numerical Abilities in Fish

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    Background: It has been hypothesised that human adults, infants, and non-human primates share two non-verbal systems for enumerating objects, one for representing precisely small quantities (up to 3–4 items) and one for representing approximately larger quantities. Recent studies exploiting fish’s spontaneous tendency to join the larger group showed that their ability in numerical discrimination closely resembles that of primates but little is known as to whether these capacities are innate or acquired. Methodology/Principal Findings: We used the spontaneous tendency to join the larger shoal to study the limits of the quantity discrimination of newborn and juvenile guppies. One-day old fish chose the larger shoal when the choice was between numbers in the small quantity range, 2 vs. 3 fish, but not when they had to choose between large numbers, 4 vs. 8 or 4 vs. 12, although the numerical ratio was larger in the latter case. To investigate the relative role of maturation and experience in large number discrimination, fish were raised in pairs (with no numerical experience) or in large social groups and tested at three ages. Forty-day old guppies from both treatments were able to discriminate 4 vs. 8 fish while at 20 days this was only observed in fish grown in groups. Control experiments showed that these capacities were maintained after guppies were prevented from using non numerical perceptual variables that co-vary with numerosity. Conclusions/Significance: Overall, our results suggest the ability of guppies to discriminate small numbers is innate and i

    Worldwide comparison of survival from childhood leukaemia for 1995–2009, by subtype, age, and sex (CONCORD-2): a population-based study of individual data for 89 828 children from 198 registries in 53 countries

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    Background Global inequalities in access to health care are reflected in differences in cancer survival. The CONCORD programme was designed to assess worldwide differences and trends in population-based cancer survival. In this population-based study, we aimed to estimate survival inequalities globally for several subtypes of childhood leukaemia. Methods Cancer registries participating in CONCORD were asked to submit tumour registrations for all children aged 0-14 years who were diagnosed with leukaemia between Jan 1, 1995, and Dec 31, 2009, and followed up until Dec 31, 2009. Haematological malignancies were defined by morphology codes in the International Classification of Diseases for Oncology, third revision. We excluded data from registries from which the data were judged to be less reliable, or included only lymphomas, and data from countries in which data for fewer than ten children were available for analysis. We also excluded records because of a missing date of birth, diagnosis, or last known vital status. We estimated 5-year net survival (ie, the probability of surviving at least 5 years after diagnosis, after controlling for deaths from other causes [background mortality]) for children by calendar period of diagnosis (1995-99, 2000-04, and 2005-09), sex, and age at diagnosis (< 1, 1-4, 5-9, and 10-14 years, inclusive) using appropriate life tables. We estimated age-standardised net survival for international comparison of survival trends for precursor-cell acute lymphoblastic leukaemia (ALL) and acute myeloid leukaemia (AML). Findings We analysed data from 89 828 children from 198 registries in 53 countries. During 1995-99, 5-year agestandardised net survival for all lymphoid leukaemias combined ranged from 10.6% (95% CI 3.1-18.2) in the Chinese registries to 86.8% (81.6-92.0) in Austria. International differences in 5-year survival for childhood leukaemia were still large as recently as 2005-09, when age-standardised survival for lymphoid leukaemias ranged from 52.4% (95% CI 42.8-61.9) in Cali, Colombia, to 91.6% (89.5-93.6) in the German registries, and for AML ranged from 33.3% (18.9-47.7) in Bulgaria to 78.2% (72.0-84.3) in German registries. Survival from precursor-cell ALL was very close to that of all lymphoid leukaemias combined, with similar variation. In most countries, survival from AML improved more than survival from ALL between 2000-04 and 2005-09. Survival for each type of leukaemia varied markedly with age: survival was highest for children aged 1-4 and 5-9 years, and lowest for infants (younger than 1 year). There was no systematic difference in survival between boys and girls. Interpretation Global inequalities in survival from childhood leukaemia have narrowed with time but remain very wide for both ALL and AML. These results provide useful information for health policy makers on the effectiveness of health-care systems and for cancer policy makers to reduce inequalities in childhood survival

    Global surveillance of cancer survival 1995-2009: analysis of individual data for 25,676,887 patients from 279 population-based registries in 67 countries (CONCORD-2)

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    BACKGROUND: Worldwide data for cancer survival are scarce. We aimed to initiate worldwide surveillance of cancer survival by central analysis of population-based registry data, as a metric of the effectiveness of health systems, and to inform global policy on cancer control. METHODS: Individual tumour records were submitted by 279 population-based cancer registries in 67 countries for 25·7 million adults (age 15-99 years) and 75,000 children (age 0-14 years) diagnosed with cancer during 1995-2009 and followed up to Dec 31, 2009, or later. We looked at cancers of the stomach, colon, rectum, liver, lung, breast (women), cervix, ovary, and prostate in adults, and adult and childhood leukaemia. Standardised quality control procedures were applied; errors were corrected by the registry concerned. We estimated 5-year net survival, adjusted for background mortality in every country or region by age (single year), sex, and calendar year, and by race or ethnic origin in some countries. Estimates were age-standardised with the International Cancer Survival Standard weights. FINDINGS: 5-year survival from colon, rectal, and breast cancers has increased steadily in most developed countries. For patients diagnosed during 2005-09, survival for colon and rectal cancer reached 60% or more in 22 countries around the world; for breast cancer, 5-year survival rose to 85% or higher in 17 countries worldwide. Liver and lung cancer remain lethal in all nations: for both cancers, 5-year survival is below 20% everywhere in Europe, in the range 15-19% in North America, and as low as 7-9% in Mongolia and Thailand. Striking rises in 5-year survival from prostate cancer have occurred in many countries: survival rose by 10-20% between 1995-99 and 2005-09 in 22 countries in South America, Asia, and Europe, but survival still varies widely around the world, from less than 60% in Bulgaria and Thailand to 95% or more in Brazil, Puerto Rico, and the USA. For cervical cancer, national estimates of 5-year survival range from less than 50% to more than 70%; regional variations are much wider, and improvements between 1995-99 and 2005-09 have generally been slight. For women diagnosed with ovarian cancer in 2005-09, 5-year survival was 40% or higher only in Ecuador, the USA, and 17 countries in Asia and Europe. 5-year survival for stomach cancer in 2005-09 was high (54-58%) in Japan and South Korea, compared with less than 40% in other countries. By contrast, 5-year survival from adult leukaemia in Japan and South Korea (18-23%) is lower than in most other countries. 5-year survival from childhood acute lymphoblastic leukaemia is less than 60% in several countries, but as high as 90% in Canada and four European countries, which suggests major deficiencies in the management of a largely curable disease. INTERPRETATION: International comparison of survival trends reveals very wide differences that are likely to be attributable to differences in access to early diagnosis and optimum treatment. Continuous worldwide surveillance of cancer survival should become an indispensable source of information for cancer patients and researchers and a stimulus for politicians to improve health policy and health-care systems

    The histology of ovarian cancer: worldwide distribution and implications for international survival comparisons (CONCORD-2)

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    Objective Ovarian cancers comprise several histologically distinct tumour groups with widely different prognosis. We aimed to describe the worldwide distribution of ovarian cancer histology and to understand what role this may play in international variation in survival. Methods The CONCORD programme is the largest population-based study of global trends in cancer survival. Data on 681,759 women diagnosed during 1995â\u80\u932009 with cancer of the ovary, fallopian tube, peritoneum and retroperitonum in 51 countries were included. We categorised ovarian tumours into six histological groups, and explored the worldwide distribution of histology. Results During 2005â\u80\u932009, type II epithelial tumours were the most common. The proportion was much higher in Oceania (73.1%), North America (73.0%) and Europe (72.6%) than in Central and South America (65.7%) and Asia (56.1%). By contrast, type I epithelial tumours were more common in Asia (32.5%), compared with only 19.4% in North America. From 1995 to 2009, the proportion of type II epithelial tumours increased from 68.6% to 71.1%, while the proportion of type I epithelial tumours fell from 23.8% to 21.2%. The proportions of germ cell tumours, sex cord-stromal tumours, other specific non-epithelial tumours and tumours of non-specific morphology all remained stable over time. Conclusions The distribution of ovarian cancer histology varies widely worldwide. Type I epithelial, germ cell and sex cord-stromal tumours are generally associated with higher survival than type II tumours, so the proportion of these tumours may influence survival estimates for all ovarian cancers combined. The distribution of histological groups should be considered when comparing survival between countries and regions

    L'ontogenesi e la filogenesi delle abilità  numeriche

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    In the last decades several studies have demonstrated that some numerical abilities are not strictly related to symbolic language and they are not a human prerogative. Recently the ability to discriminate between two quantities has been demonstrated also in fish. The aim of this project was to study the mechanisms underlying the non verbal numerical abilities in vertebrates. I investigated whether fish possess two independent numerical systems for the representation of small (4) number or they possess a unique system that operates on the whole numerical scale. Both spontaneous choice and training experiments demonstrated that the ability to discriminate between large quantities was approximate and strongly dependent on the ratio between the numerosities, while discrimination in the small quantity range was not dependent on ratio and discriminating 3 from 4 was as easy as discriminating 1 from 4. The second part of the project regards the ontogeny of the ability to discriminate quantities. These experiments showed that the ability of fish to discriminate small numbers is innate and it is displayed immediately at birth while discrimination of large numbers emerges later as a result of both maturation and social experience. The third part concerns the role of non numerical variables in the discrimination of quantities. These experiments showed that fish are able to discriminate quantities even after the access to non numerical cues was made difficult and that learning a discrimination by using only numerical information is not more difficult than learning it by using only the non numerical variables. Finally, to investigate whether fish and humans share the same non verbal numerical systems, I carried out some experiments in which I compared fish and university students for their ability to discriminate the same numerical contrasts. Taken together these findings support the suggestion that discrete and continuous quantities are processed in humans and nonhuman animals by systems that evolved from a common ancestor more than 450 million years ago.Negli ultimi anni è stato ampiamente dimostrato che le capacità numeriche non sono una prerogativa esclusivamente umana, infatti alcune abilità numeriche sono presenti anche in molte specie animali. Recentemente è stato dimostrato che anche i pesci sono in grado di compiere delle discriminazioni numeriche, e per questo sono stati utilizzati come modello sperimentale nel presente lavoro, allo scopo di approfondire lo studio dei meccanismi alla base delle abilità numeriche non verbali nei vertebrati. Una prima serie di esperimenti ha indagato se vi siano uno o due sistemi numerici non verbali nei pesci. I risultati, provenienti sia dagli esperimenti condotti con la procedura della scelta spontanea che da quelli condotti con la procedura di addestramento, hanno evidenziato come la capacità di discriminare grandi quantità (>4) sia fortemente influenzata dal rapporto numerico, mentre le discriminazioni tra piccole quantità (<4) non lo siano, in quanto discriminare 1 vs. 4 sarebbe facile quanto discriminare 3 vs. 4. Un secondo aspetto analizzato riguarda l’ontogenesi delle abilità numeriche. Questi esperimenti hanno evidenziato che nei pesci la capacità di discriminare piccole quantità è innata e presente fin dalla nascita, mentre quella di discriminare grandi quantità emerge più tardi come risultato della maturazione e dell’esperienza sociale. In seguito sono stati condotti una serie di esperimenti allo scopo di valutare il ruolo delle variabili non numeriche nelle discriminazioni di quantità: è emerso che i pesci sono in grado di discriminare diverse quantità anche quando l’accesso alle variabili non numeriche viene limitato; inoltre è stato dimostrato come per i pesci non sia più difficile apprendere una discriminazione sulla base della sola informazione numerica piuttosto che affidandosi alle sole variabili non numeriche, suggerendo che anche per i pesci il numero potrebbe essere una caratteristica primaria così come lo sono altre dimensioni degli stimoli. Infine in una serie di esperimenti le prestazioni dei pesci sono state confrontate con quelle degli esseri umani adulti in compiti paragonabili, allo scopo di verificare se i meccanismi alla base della discriminazione non verbale di quantità siano gli stessi in tutti i vertebrati. Nel loro insieme questi dati supportano l’ipotesi che sia nell’uomo che nei pesci le quantità siano elaborate attraverso dei sistemi che potrebbero essere evoluti da un comune antenato più di 450 milioni di anni fa

    Musicians outperform nonmusicians in magnitude estimation: Evidence of a common processing mechanism for time, space and numbers

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    It has been proposed that time, space, and numbers may be computed by a common magnitude system. Even though several behavioural and neuroanatomical studies have focused on this topic, the debate is still open. To date, nobody has used the individual differences for one of these domains to investigate the existence of a shared cognitive system. Musicians are known to outperform nonmusicians in temporal discrimination tasks. We therefore observed professional musicians and nonmusicians undertaking three different tasks: temporal (participants were required to estimate which of two tones lasted longer), spatial (which line was longer), and numerical discrimination (which group of dots was more numerous). If time, space, and numbers are processed by the same mechanism, it is expected that musicians will have a greater ability, even in nontemporal dimensions. As expected, musicians were more accurate with regard to temporal discrimination. They also gave better performances in both the spatial and the numerical tasks, but only outside the subitizing range. Our data are in accordance with the existence of a common magnitude system. We suggest, however, that this mechanism may not involve the whole numerical range
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