23 research outputs found
Tychus spurius Sabella, sp. n.
No full textTychus spurius Sabella, sp. n. (Figs. 5, 16– 17) Type material. Holotype: TURKEY: Sinop Prov.: ɗ, above Bektas, 23 km N of Boyabat, 1100 m, fagetum leal litter, 20.V. 1976 (C. Besuchet & I. Löbl) (MHNG). Paratypes: TURKEY: Sinop Prov.: 2 ɗɗ, Lala, near Sinop, 20.V. 1976 (C. Besuchet & I. Löbl) (MHNG). Description. Body length 1.7–1.75 mm. Winged. Body uniformly brown with reddish elytra and yellow legs and palpi. Head sligthly wider (0.31 mm) than long (0.30 mm), frontal rostrum 0.165–0.17 mm wide and 0.06 long, a small tooth in front. Eyes well developed with 20–26 ommatidia. Occipital region slightly convex. Last segment of maxillary palpi 0.2 mm long and 0.08 mm wide. Pronotum wider (0.37–0.385 mm) than long (0.35–0.365 mm) with small and slightly impressed lateral antebasal foveae. Elytra wider (0.685 mm) than long (0.50 mm) with humeri not very protruding. Discal fovea extended posteriorly in large and deep discal stria reaching more than half elytral length. Abdomen with 1 st tergite 0.22–0.235 mm long, basal impression extending more than 1 / 3 of tergite width. Male. Antennae (Fig. 5) 0.75 mm long, club 0.31 mm long; scapus and segment 2 distinctly longer than wide; segment 3 longer than wide and narrowed at base; 4 slightly longer than wide; 5 slightly wider than 4 and slightly longer than wide; 6 wider than long, 7 longer than wide; 8 wider than long and shorter than previous segments. Metaventrite with deep median impression. Legs with femora and tibiae of all legs slightly thickened, posterior margin of mesotrochanters extended into small median spine, mesotibiae with small subapical spur, metatibiae with apical spur. All abdominal sternites not modified. Aedeagus (Figs. 16–17) 0.44 mm long, dorsal apophysis of median lobe sinuate and canaliculate, slightly enlarged at apex, with medial margin prolonged into short spine-like process extended medially and in basal third extendend into short spine. Ventral portion of median lobe slightly shorter than dorsal apophysis, at base relatively large, extended into two spine-like apophyses: the lateral distinctly longer, almost straight, in distal third turned upwards, in basal third of lateral margin with short spine; the medial slightly recurved and directed medially. Female. Unknown. Comparative notes. Tychus spurius sp. n. is similar to T. anser Sabella & Kurbatov, 2002 but distinguished from the latter by the shape of ventral portion and dorsal apophysis of the median lobe of aedeagus. Tychus florentinus species group (Sabella & Poggi, 1997) Note. In the original description of Tychus coiffaiti Besuchet, 1958 the author outlined that this species is similar to T. florentinus Reitter, 1884, T. jonicus Holdhaus, 1908 and T. serbicus Reitter, 1884. All three were placed in the florentinus species group established by Sabella and Poggi (1997), but T. coiffaiti remained unassigned. The discovery of T. grassator, a species very similar to T. coiffaiti, convinced us to include both species in this group of which they present all the diagnostic characters.Published as part of Sabella, Giorgio, Besuchet, Claude & Kurbatov, Sergey A., 2011, New species of Tychini from Turkey and Japan (Coleoptera: Staphylinidae: Pselaphinae), pp. 22-34 in Zootaxa 2764 on page 28, DOI: 10.5281/zenodo.20353
Faronus rica Kurbatov & Mifsud & Sabella 2019, sp. nov.
No full textFaronus rica sp. nov. (Figs 1, 2, 5, 7, 9, 11) Type material. Holotype, ♂ (MHNG). MALTA, Wied Babu, 50 m, 23.xi.2017, sifting litter of Ceratonia siliqua (S. Kurbatov). Paratype, 1 ♀ (MHNG); same locality of holotype, 24.xi.2017, sifting litter of Ceratonia siliqua (D. Mifsud & G. Sabella). Description. Male. Body length 1.75 mm, entirely reddish brown with yellowish palpi and legs. Relatively dense pubescence of long and flattened golden setae on head, pronotum, elytra and abdomen; other setae, yellowish and suberect present on sides of antennae, palpi and legs. Tegument smooth and shiny. Head triangular, wider (0.35 mm) than long (0.22 mm). Wide and deep longitudinal median frontal sulcus, which starts from the frontal lobe and forks in the middle; then bifurcates towards the base of the occipital region. Temples slightly shorter than eyes and marginally protruding, each forming an angle of about 70° with the longitudinal axis of the head, and ending in an annular organ. Eyes well developed and protruding with 32-33 facets. Antennae with cylindrical scape about twice as long as wide, pedicel as long as wide, antennomere 3 is the smallest of the flagellum and wider than long, antennomere 4 slightly longer than wide, antennomeres 5-6 as long as wide, antennomeres 7-8 slightly wider than long. The club is not so distinct having antennomeres 9-10 wider than long and wider than preceding articles; antennomere 11 slightly wider than 10 and slightly longer than wide. Pronotum distinctly wider (0.41 mm) than long (0.31 mm), widest in the middle; lateral discal fovea, lateral antebasal fovea, medial antebasal fovea, and outer antebasal fovea present and distinct; antebasal sulcus lacking. Disc convex in the middle with a horseshoe-shaped impression, its transversal part (including the median antebasal fovea) distinctly impressed whereas the two longitudinal branches very weakly impressed; the latter bearing four adjacent foveae. Elytra wider (0.51 mm) than long (0. 40 mm) and longer than pronotum, and gradually widen from the base to the apex. Two basal foveae; sutural stria reaching apical part of elytra with three very small adjacent foveae; discal stria reaching about two thirds of elytral length. Humeri not distinctly protruding followed by a weak lateral depression. Hind wings absent. Abdomen distinctly longer than both pronotum and elytra together, the first three visible tergites having the same length. Posterior margin of 2 nd ventrite slightly raised in the middle; posterior margin of 3 rd ventrite strongly raised and forming an open cup-shaped structure in the middle (Fig. 1); the central part of the 4 th ventrite depressed having the middle part of posterior margin raised as a form of lamina at 90° in such a way that it fits into the cupshaped structure just described and apically slightly curved posteriorly (Fig. 2). Legs with protibia widest in the middle (Fig. 9) with mesal margin sinuate in distal half, apically having a short rounded process; mesotibiae slightly enlarged in the apical third with a similar terminal process as in the protibiae. Aedeagus (Fig. 7) length 0.33 mm, with well-developed slender parameres widest in the middle, left paramere with two apical setae and right paramere with one; two additional medial setae are also present towards the centre of each paramere. Median part of aedeagus wide and distinctly sclerotized with a pointed apical part on the right; apical membrane equipped with multiple small spiniform processes. Female. Body (Fig. 5) length 1.80 mm entirely light reddish with yellow palpi and legs. Pubescence and tegument as in male. Head as in male, wider (0.31 mm) than long (0.21 mm). Eyes well developed and protruding with 25–27 facets. Antennae similar to those of male. Pronotum similar to that of male, also for the foveae system on dorsal surface, wider (0.36 mm) than long (0.31 mm). Elytra wider (0.44 mm) than long (0.33 mm), similar to those of male, only less distinctly enlarged from base to apex. Abdomen as in male in dorsal view, and with unmodified abdominal ventrites. Legs unmodified. Telisternite as in figure 11. Comparative notes. Faronus rica sp. nov. belongs to the F. hispanus species group (Sabella 1993) characterized by males having secondary sexual characters on abdominal ventrites, aedeagus with sinuate parameres, well sclerotized median part bearing multiple small spiniform processes apically. The group currently accommodates F. hispanus Saulcy, 1870, known from Portugal (Algarve), Spain (Catalonia, Valencia, Andalusia) and northern Algeria; F. insularis Sainte-Claire Deville, 1908, endemic to Sardinia and circum-sardinian islands and southern Corsica; F. siculus Fiori, 1913, endemic to Sicily, F. insignis Besuchet, 1958, known from the Balearic Islands (Majorca and Minorca), and F. rica sp. nov. endemic to Malta. Faronus rica sp. nov. is closely related to F. siculus with which many morphological characters are shared. It differs from this species on the basis of the following features: (i) protibia of male widest in the middle with mesal margin sinuate in distal half (cfr. Figs. 9, 10); (ii) left side of median part of aedeagus pointed apically (cfr. Figs. 7, 8); and (iii) the highly modified 3 rd and 4 th ventrites having a strongly raised open cup-shaped structure in the middle (on 3 rd ventrite) and a 90° raised lamina (on 4 th ventrite) which fits into the cup-shaped structure and apically curved posteriorly (cfr. Figs.1-4). Females of both species are impossible to discriminate on the basis of morphological features. Some morphological differences in the apical region of the telisternite were found and these are illustrated in figures 11 and 12. Ecological notes. The two specimens of Faronus rica sp. nov. were collected in November by sifting leaf litter under Ceratonia siliqua, in a valley system at 50 m of altitude, along with numerous specimens of Tychus opuntiae (Schmidt-Goebel, 1836). Wied Babu (Fig. 6) is a fine example of a river valley and creek. The area is rich in endemic species such as the National Plant for Malta (Cheirolophus crassifolius) for which Wied Babu is the type locality. Etymology. This species is dedicated to Yves and Patricia Rica, a French family residing in Malta who are always very helpful and contribute financially for entomological research work carried out by the corresponding author in Malta. They offered free accommodation to many delegates present at the 4 th International Congress of Biodiversity held in Malta (13-16 th November 2017) and thereafter, this provided the right opportunity for the present authors to do intensive field work and to discover the new species which we gladly and proudly dedicate to them.Published as part of Kurbatov, Sergey A., Mifsud, David & Sabella, Giorgio, 2019, A new species of Faronus Aubé, 1844, endemic to Malta (Coleoptera, Staphylinidae, Pselaphinae), pp. 417-422 in Zootaxa 4571 (3) on pages 418-420, DOI: 10.11646/zootaxa.4571.3.9, http://zenodo.org/record/261280
Carmilla e Sabella: em busca de uma identidade feminina em Joseph Sheridan Le Fanu e Tanith Lee
No full textEste trabalho teve como objetivo realizar uma análise comparativa entre duas obras literárias que têm como foco a questão da representação literária feminina. Ao analisar os textos Carmilla (1872), de Joseph Sheridan Le Fanu, e Sabella (1980), de Tanith Lee, buscamos apontar alguns traços comuns característicos quanto às descrições das personagens femininas e as posturas que assumem diante da sociedade na qual estão inseridas, a fim de encontrar alguns possíveis aspectos norteadores para a construção da identidade feminina literária. A partir de um olhar mais aprofundado para as personagens-título Carmilla e Sabella — ambas vampiras e representativas de dois momentos distintos da literatura de ficção inglesa — retratamos os contextos histórico-sociais em que os autores se inserem. A análise baseou-se em algumas teorias feministas desenvolvidas e disseminadas ao longo dos anos 70 e 80, que visam discutir os novos posicionamentos da mulher dentro de contextos sociais até então “proibidos”, tais como trabalho, política e sexualidade. Interagimos também com textos que relacionam a representação social da mulher ligada à figura mitológica do vampiro – representação essa diretamente associadas às transformações emocionais que tratam do embate primitivo do bem vs. o mal.The aim of this study was to make a comparative analysis focusing on the female literary representations present in two English novels. Through the study of the novels Carmilla (1872), by Joseph Sheridan Le Fanu, and Sabella (1980), by Tanith Lee, we examined the main common characteristics from female characters and their attitudes within the society to which they belong, and with the purpose of finding some possible points leading to a literary female identity construction. From a deep contact with the title-characters Carmilla and Sabella – both female vampires and also representatives of distinct English literary fiction periods – we depict the social-historical contexts to which each author belongs. The analysis is based on some feminist theories developed and propagated along of the 70’s and the 80’s, which discuss the new places occupied by women in social contexts so far known as “banned”, like out-of-house works, politics and sexuality. We also interact with texts related to social female representations linked to the mythological vampire figure – a kind of representation directly associated to some emotional transformations dealing with the primitive opposition between good vs. evil
Carmilla e Sabella: em busca de uma identidade feminina em Joseph Sheridan Le Fanu e Tanith Lee
No full textEste trabalho teve como objetivo realizar uma análise comparativa entre duas obras literárias que têm como foco a questão da representação literária feminina. Ao analisar os textos Carmilla (1872), de Joseph Sheridan Le Fanu, e Sabella (1980), de Tanith Lee, buscamos apontar alguns traços comuns característicos quanto às descrições das personagens femininas e as posturas que assumem diante da sociedade na qual estão inseridas, a fim de encontrar alguns possíveis aspectos norteadores para a construção da identidade feminina literária. A partir de um olhar mais aprofundado para as personagens-título Carmilla e Sabella — ambas vampiras e representativas de dois momentos distintos da literatura de ficção inglesa — retratamos os contextos histórico-sociais em que os autores se inserem. A análise baseou-se em algumas teorias feministas desenvolvidas e disseminadas ao longo dos anos 70 e 80, que visam discutir os novos posicionamentos da mulher dentro de contextos sociais até então “proibidos”, tais como trabalho, política e sexualidade. Interagimos também com textos que relacionam a representação social da mulher ligada à figura mitológica do vampiro – representação essa diretamente associadas às transformações emocionais que tratam do embate primitivo do bem vs. o mal.The aim of this study was to make a comparative analysis focusing on the female literary representations present in two English novels. Through the study of the novels Carmilla (1872), by Joseph Sheridan Le Fanu, and Sabella (1980), by Tanith Lee, we examined the main common characteristics from female characters and their attitudes within the society to which they belong, and with the purpose of finding some possible points leading to a literary female identity construction. From a deep contact with the title-characters Carmilla and Sabella – both female vampires and also representatives of distinct English literary fiction periods – we depict the social-historical contexts to which each author belongs. The analysis is based on some feminist theories developed and propagated along of the 70’s and the 80’s, which discuss the new places occupied by women in social contexts so far known as “banned”, like out-of-house works, politics and sexuality. We also interact with texts related to social female representations linked to the mythological vampire figure – a kind of representation directly associated to some emotional transformations dealing with the primitive opposition between good vs. evil
Carmilla e Sabella: em busca de uma identidade feminina em Joseph Sheridan Le Fanu e Tanith Lee
No full textEste trabalho teve como objetivo realizar uma análise comparativa entre duas obras literárias que têm como foco a questão da representação literária feminina. Ao analisar os textos Carmilla (1872), de Joseph Sheridan Le Fanu, e Sabella (1980), de Tanith Lee, buscamos apontar alguns traços comuns característicos quanto às descrições das personagens femininas e as posturas que assumem diante da sociedade na qual estão inseridas, a fim de encontrar alguns possíveis aspectos norteadores para a construção da identidade feminina literária. A partir de um olhar mais aprofundado para as personagens-título Carmilla e Sabella — ambas vampiras e representativas de dois momentos distintos da literatura de ficção inglesa — retratamos os contextos histórico-sociais em que os autores se inserem. A análise baseou-se em algumas teorias feministas desenvolvidas e disseminadas ao longo dos anos 70 e 80, que visam discutir os novos posicionamentos da mulher dentro de contextos sociais até então “proibidos”, tais como trabalho, política e sexualidade. Interagimos também com textos que relacionam a representação social da mulher ligada à figura mitológica do vampiro – representação essa diretamente associadas às transformações emocionais que tratam do embate primitivo do bem vs. o mal.The aim of this study was to make a comparative analysis focusing on the female literary representations present in two English novels. Through the study of the novels Carmilla (1872), by Joseph Sheridan Le Fanu, and Sabella (1980), by Tanith Lee, we examined the main common characteristics from female characters and their attitudes within the society to which they belong, and with the purpose of finding some possible points leading to a literary female identity construction. From a deep contact with the title-characters Carmilla and Sabella – both female vampires and also representatives of distinct English literary fiction periods – we depict the social-historical contexts to which each author belongs. The analysis is based on some feminist theories developed and propagated along of the 70’s and the 80’s, which discuss the new places occupied by women in social contexts so far known as “banned”, like out-of-house works, politics and sexuality. We also interact with texts related to social female representations linked to the mythological vampire figure – a kind of representation directly associated to some emotional transformations dealing with the primitive opposition between good vs. evil
Considerations for incorporating real-time PCR assays into routine marine biosecurity surveillance programmes: a case study targeting the Mediterranean fanworm (Sabella spallanzanii) and club tunicate (Styela clava)
No full textMolecular techniques may provide effective tools to enhance marine biosecurity surveillance. Prior to routine implementation, evidence-based consideration of their benefits and limitations is needed. In this study, we assessed the efficiency and practicality of visual diver surveys and real-time PCR assays (targeting DNA and RNA) for detecting two marine invasive species whose infestation levels varied between species and location; Sabella spallanzanii and Styela clava. Filtered water samples (n=171) were collected in parallel with dive surveys at two locations as part of the New Zealand Marine High Risk Site Surveillance programme: Nelson Harbour (27 sites) and Waitemata Harbour (30 sites). Diver surveys resulted in a greater number of detections compared to real-time PCR: S. clava â 21 versus 5 sites in Nelson, 6 versus 1 in Auckland; S. spallanzanii â 18 versus 10 in Auckland, no detections in Nelson. Occupancy modelling derived detection probabilities for the real-time PCR for S. clava were low (14%), compared to S. spallanzanii (66%). This could be related to abundances, or species-specific differences in DNA shedding. Only one RNA sample was positive, suggesting that most detections were from extracellular DNA or non-viable fragments. While molecular methods cannot yet replace visual observations, this study shows they provide useful complementary information.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author
Abundância e diversidade de poliquetas nos canhões submarinos portugueses
No full textMestrado em Biologia MarinhaO trabalho foi realizado na costa Oeste da Margem Ibérica em três canhões submarinos Portugueses: Nazaré, Setubal e Cascais, a três profundidades: 1000m, 3400m e 4300m; e em duas zonas de talude continental, adjacentes aos canhões de Nazaré e Setubal, a 1000m de profundidade. São estudadas as comunidades de poliquetas com o objectivo de identificar diferenças entre as comunidades do talude continental e dos canhões submarinos, determinar a ocorrência de padrões de abundância, biomassa e diversidade relacionados com o gradiente de profundidade e interpretar essas diferenças em relação com as condições ambientais dos diferentes canhões.
No que se refere à estrutura vertical no sedimento, a macrofauna de uma forma geral apresenta um decréscimo de abundância e do número de espécies com o aumento da profundidade do sedimento. Apesar disso, a biomassa apresenta valores mais elevados a maior profundidade do sedimento.
De acordo com a abundância, biomassa, dominância e estrutura da comunidade os diferentes ambientes estudados (canhão e talude continental) apresentam diferenças significativas, mas também se detectou variabilidade entre as comunidades dos diferentes canhões e a diferentes profundidades. A 1000m, nos canhões e talude continental, a dominância é baixa e a equitabilidade elevada, mas a diversidade foi geralmente mais baixa no talude continental. A esta profundidade as comunidades apresentam elevadas abundâncias de carnívoros e omnívoros. A dominância foi mais elevada para todos os canhões a 3400m, apesar dos canhões de Nazaré e Setúbal apresentarem comunidades mais dominadas, principalmente pelos detritívoros de superfície e de sub-superfície. No que respeita à densidade de indivíduos, os canhões submarinos da Nazaré e Setúbal apresentam valores mais elevados, com valores máximos a profundidades intermédias, mas no caso da biomassa média individual, os valores mais elevados são encontrados no canhão de Cascais.
As variações na composição e estrutura das comunidades podem ser relacionadas com a origem e distribuição de carbono orgânico particulado que é interpretado como a principal fonte de alimento para as comunidades bentónicas dos canhões.
Concluindo, neste trabalho existem evidências de que as diferentes áreas analisadas, em relação às comunidades de poliquetas, apresentam padrões diferentes ao longo do gradiente de profundidade e nos três canhões, reforçando a idéia que os canhões são sistemas com caracteristicas únicas e comunidades particulares, diferindo de outros canhões.The present work was undertaken in the West Iberian Margin, in three different canyons of the Portuguese coast: Nazaré, Setúbal and Cascais, at three different depths: 1000m, 3400m and 4300m; and in two open slope sites, adjacent to Nazaré and Setubal canyons, at 1000m. This work is focused on the study of polychaete assemblages and aimed to identify differences between open slope and canyon assemblages, to determine the occurrence of abundance, biomass and diversity patterns related to the depth gradient and to investigate differences possibly related to environmental conditions in different canyons.
Regarding the vertical structure of the sediment, macrofauna generally presented decreasing abundance and species richness with increasing depth of sediment layers. Despite this, biomass presented higher values at deeper sediment layers.
The two different deep-sea environments (canyon and open slope) showed significant differences, namely in their abundance, biomass, dominance and community structure. However, important differences between and within canyons were also identified. Both canyons and open slopes exhibited low dominance and high evenness, at 1000m, though diversity was generally lower in open slopes. At this depth, communities presented higher relative abundances of carnivorous and omnivorous. On the other hand, dominance was higher at 3400m for all canyons, with Nazaré and Setúbal showing more dominated communities than Cascais, mainly because of the great abundance of surface deposit feeders and sediment deposit feeders. Regarding density, Nazaré and Setúbal canyons presented higher values, with a maximum at intermediate depths, while mean individual biomass was greater in Cascais.
Variability in species composition and community structure are related to the source and distribution of particulate organic carbon which is the major food source for the benthic assemblages in the studied canyons.
In conclusion, our results showed that the different areas analysed presented different patterns regarding polychaete assemblages, reinforcing the idea of canyons as individual systems with particular features and communities
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Implementing a Protocol to Monitor Cardiometabolic Syndrome in Patients Prescribed Atypical Antipsychotics
No full textAtypical or second-generation antipsychotics (SGAs) are a vital part of the management of many psychotic disorders, as well as behavioral and psychological symptoms. However, these medications have serious cardiometabolic complications, such as an increase in obesity, glucose intolerance, dyslipidemia, and hypertension, and can place the patient at serious risk for cardiovascular disease. The American Diabetes Association (ADA) and the American Psychiatric Association (APA) recommend clinical guidelines for metabolic screening, which requires the regular monitoring of patients treated with SGAs (ADA, 2004). The goal of this quality improvement project was to 1) implement a metabolic screening protocol based on ADA and APA guidelines for patients admitted to an acute psychiatric hospital who were treated with second-generation antipsychotics and 2) increase healthcare personnel awareness of metabolic monitoring guidelines and metabolic syndrome. This quality improvement project was implemented at an inpatient behavioral hospital in New England. A protocol for the monitoring of metabolic disturbances was placed in thirty patients’ medical charts, who were age eighteen and over, had been prescribed SGAs, and had been taking the medication daily since the admission to the hospital. Twenty-one psychiatric mental health staff members attended the educational interventions that were conducted by the author of the project A retrospective chart review was performed post-intervention to assess guideline adherence by comparing the percentage of tests ordered pre-intervention versus the during the post-intervention period. Data were collected over a three-month period starting from November 2018 until January 2019. The healthcare personnel awareness of metabolic monitoring guidelines and metabolic syndrome have been evaluated by a survey. After the intervention period, there were slight increases in the numbers of orders for hemoglobin A1c and lipid panel, but rates of other baseline monitoring parameters (such as weight and blood pressure) remained the same or did not improve. The waist circumference was one of the indicators that had not been measured, even after the implementation of the screening protocol.Doctor of Nursing Practice, Psychiatric Mental Health Nurse Practitioner (PMHNP
UninaStudents @ SardiStance: Stance Detection in Italian Tweets - Task A
No full textThis document describes a classification system for the SardiStance task at EVALITA 2020. The task consists in classifying the stance of the author of a series of tweets towards a specific discussion topic. The resulting system was specifically developed by the authors as final project for the Natural Language Processing class of the Master in Computer Science at University of Naples Federico II. The proposed system is based on an SVM classifier with a radial basis function as kernel making use of features like 2 char-grams, unigram hashtag and Afinn weight computed on automatic translated tweets. The results are promising in that the system performances are on average higher than that of the baseline proposed by the task organizers.Questo documento descrive un sistema di classificazione per il task SardiStance di EVALITA 2020. Il task consiste nel classificare la posizione dell’autore di una serie di tweets nei confronti di uno specifico topic di discussione. Il sistema risultante è stato specificamente sviluppato dagli autori come progetto finale per il corso di Elaborazione del Linguaggio Naturale nell’ambito del corso di laurea magistrale in Informatica presso l’università degli studi di Napoli Federico II. Il sistema qui proposto si basa su un classificatore SVM con una funzione radiale di base come kernel facendo uso di features come 2 char-grams, unigram hashtag e l’Afinn weight calcolato sui tweet tradotti in automatico. I risultati sono promettenti in quanto le performance sono in media superiori rispetto a quelle della baseline proposta dagli organizzatori del task
The search for a filter-feeding alternative for integrated shrimp aquacultures– a preliminary study with the polychaete <i>Sabella spallanzanii</i> for water quality improvement
No full textIntroduction
Aquaculture practices, like any other human activity, affect the environment in different ways. Some can be considered beneficial while others are in conflict with long-term sustainability of natural ecosystems.
Recently, some attention has been dedicated to the effects of discharges of effluents from certain types of aquaculture. Aquaculture operations cause the release of metabolic waste products such as faeces, pseudofaeces, excreta and uneaten food which is considered one of the most important factors causing organic and inorganic loading in the vicinities of aquatic farms (Grigorakis & Rigos, 2011). The amount of uneaten feed relies mostly on the personnel experience and qualifications, feeding management (automatic or hand feeding), and the ingredients comprising the feed (Grigorakis & Rigos, 2011; Pillay, 2004). Indeed, effluents from shrimp aquaculture typically are enriched in suspended solids, nutrients, chlorophyll a and with an increased biochemical oxygen demand (Páez-Osuna, 2001).
Suspended solids have been considered one of the most important waste products affecting the quality of the receiving waters and their environment (Pillay, 2004). Aquatic animals need a high concentration of protein in their feed since their energy production pathway requires the oxidation and catabolism of proteins. Estimates of nutrient retention and potential release by fish into the water are not readily available, and are changing rapidly as feed, feeding practices, and culture methods evolve.
Also, both in aquaculture facilities and in natural aquatic environment, the occurrence several diseases have emerged as a serious economic and ecological issue, and are a significant constraint to the expansion of the industry. The control of endemic diseases imposes severe year-on-year costs on producers. A global estimate of disease losses ranges about 3 to 4 billion USD per year (Stabili et al., 2010). For example, white-spot syndrome of shrimp (WSS) has cost billions of dollars world-wide. Moreover, the elimination of disease outbreaks, such as ISA (Infectious Salmon Anemia) in Scotland in 1998/1999, caused unexpected expenditure for both the industry and government (Murraya & Peeler, 2005).
Even though water is the major recipient of dissolved residues from aquaculture, a considerable portion of the solid material is retained inside the ponds, discharge canals or in the vicinity of the farms. Both the culture media and coastal habitats where the activity is practiced usually shows high rates of biological activity and organic matter decomposition. Recently, particular emphasis has been directed on development sustainable approaches to coastal aquaculture. In this sense, the promotion of ecological practices to improve the ecosystem health has been highly encouraged, including water recycling, effluent management and biological treatment by integrated culture (Marinho-Soriano et al., 2011).
The use of filter-feeding organisms as nutrient (inorganic and organic) extractors has proven to be a valid alternative for nutrient bioremediation. Some of the most frequently tested organisms are mollusks, which filter organic particles and phytoplankton (Marinho-Soriano et al., 2011).
Integrated Multi-trophic Aquaculture (IMTA) has been proposed to achieve environmental sustainability through biomitigation of aquaculture wastes which, as compared to other accompanying methods, has advantages that may include economic stability by product diversification and risk reduction, and social acceptability through best management practices (Troell et al., 2009; Barrington et al., 2009). IMTA is a practice in which the by-products (wastes) from one species are recycled to become inputs (fertilizers, food and energy) for another through the cultivation, in the right proportions, of fed aquaculture species (e.g. finfish/shrimp) with organic extractive species (e.g. suspension and deposit feeders), and inorganic extractive aquaculture species (e.g. seaweeds) (Troell et al., 2009; Barrington et al., 2009).
The reduction of microbial pollution within aquaculture can be achieved by the use of living organisms. Literature available reveals the potential capability of some invertebrates to remediate heavy metals, microbial contaminants, hydrocarbons, nutrients and persistent organic pollutants (Khoi & Fotedar, 2012; Stabili et al., 2006). Filter-feeding marine macroinvertebrates filter large volumes of water for their food requirements and exert high efficiency in retaining small particles including bacteria. The Mediterranean polychaete Sabella spallanzanii showed ability to filter, accumulate and remove from waste, bacterial groups including human potential pathogens and vibrios (Stabili et al., 2010). Licciano et al. (2005) calculated the clearance rates and filtration efficiencies for S. spallanzanii and Vibrio alginolyticus, revealing the ability of sabellids to filter bacteria with high efficiency. Therefore, sabellids are considered suitable to use in aquaculture farms as biofilters, also considering their action in removing suspended solids in waste waters to which bacteria can be attached.
The aim of the present study was to assess the bioremediation potential of the filter-feeding polychaete Sabella spallanzanii, by its ability to remove bacterial groups, co-cultured with the highly valued marine shrimp Palaemon sp. Additionally, polychaete and shrimp growth was measured over time.
Material and Methods
In 2012, specimens of S. spallanzanii were hand collected from Peniche and Olhão coasts (Portugal) and, after an acclimatization period, they were randomly inserted in a net containing 14 individuals. The nets were inserted in an experimental recirculating aquaculture system, assembling shrimp Palaemon sp., filter-feeding polychaete S. spallanzanii and the macroalgae Ulva sp. rearing tanks. S. spallanzanii rearing tank received the wastes from the shrimp rearing tank. Their survival, growing capability and bacterial removal by filter-feeding was evaluated.
The bacteriological analyses were performed using the water samples collected in the shrimp tanks at two sampling times: one time before starting water recirculation (T0), and after 21 days of experiment (T3). Bacteriological analyses included the quantitative analyses of culturable heterotrophic bacteria (22ºC), total culturable bacteria at 37ºC, culturable halophilic vibrios at 22 and 35ºC, and E. coli.
Results and Discussion
The results obtained in growth capability of S. spallanzanii showed an increase of 9.34% in weight, corresponding to 7.7 mg day-1, during the experiment. This could be explain due to the higher suspended solids in the culture medium. Stabili et al. (2010) reported a mean increase of total polychaete biomass of 9.0 mg day-1.
Relatively to bacteriological analysis, the density of heterotrophic bacteria at 37ºC decreased substantially (Fig. 1a). The abundance of heterotrophic bacteria at 22ºC increased from T0 to T3 (Fig. 1b). This increasing density pattern of heterotrophic bacteria at 22ºC is in accordance with Stabili et al. (2010). The author stated that could be related with the effect of temperature, assessed by Pomeroy & Wiebe (2001). However, in this study no large temperature changes occur. Thus, more intensive bacteriological analyses should be done before performing any assumptions.
Regarding culturable presumptive vibrios, the abundance decreased from T0 to T3 at 22 and 35ºC (Fig. 2).
Regarding to E.coli, it was possible to observe a density decrease of 90% at the end of the experiment (Fig. 3). According with the decree-law n.º 236/98 of August 1st (N.º 176 – 1998), the maximum value allowable for faecal coliforms is 2000 per 100 mL, and the maximum value recommended is 100 per 100 mL. The results for E. coli stated previously are in accordance with the decree-law requirements.
The use of S. spallanzanii as bioremediator of microbial pollution revealed to be efficient in a more complex culture system. The integration of this species in the culture system plays an important role since it is able to filter, accumulate and remove several bacterial groups from the water, including human potential pathogens, and thus, reduces susceptibility to disease outbreaks
