676 resultados para Net reproductive rate
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INTRODUZIONE: L’integrazione mente-corpo applicata ad un ambito patologico predominante in questi tempi, come il cancro, è il nucleo di questa tesi. Il background teorico entro cui è inserita, è quello della Psiconeuroendocrinoimmunologia (Bottaccioli, 1995) e Psico-Oncologia. Sono state identificate, nella letteratura scientifica, le connessioni tra stati psicologici (mente) e condizioni fisiologiche (corpo). Le variabili emerse come potenzialmente protettive in pazienti che si trovano ad affrontare il cancro sono: il supporto sociale, l’immagine corporea, il coping e la Qualità della Vita, insieme all’indice fisiologico Heart Rate Variability (HRV; Shaffer & Venner, 2013). Il potenziale meccanismo della connessione tra queste variabili potrebbe essere spiegato dall’azione del Nervo Vago, come esposto nella Teoria Polivagale di Stephen Porges (2007; 2009). OBIETTIVI: Gli obiettivi principali di questo studio sono: 1. Valutare l’adattamento psicologico alla patologia in termini di supporto sociale percepito, immagine corporea, coping prevalente e qualità della vita in donne con cancro ovarico; 2. Valutare i valori di base HRV in queste donne; 3. Osservare se livelli più elevati di HRV sono associati ad un migliore adattamento psicologico alla patologia; 4. Osservare se una peggiore percezione dell’immagine corporea e l’utilizzo di strategie di coping disadattive sono associate ad una Qualità della Vita più scarsa. METODO: 38 donne affette da cancro ovarico, al momento della valutazione libere da patologia, sono state reclutate presso la clinica oncologica del reparto di Ginecologia dell’Azienda Ospedaliero-Universitaria di Parma, Italia. Ad ogni partecipante è stato chiesto di compilare una batteria di test composta da: MSPSS, per la valutazione del supporto sociale percepito; DAS-59, per la valutazione dell’immagine corporea; MAC, per la valutazione delle strategie di coping prevalenti utilizzate verso il cancro; EORTC-QLQ30, per la valutazione della Qualità della Vita. Per ogni partecipante è stato registrato HRV di base utilizzando lo strumento emWave (HeartMath). RISULTATI PRINCIPALI: Rispondendo agli obiettivi 1 e 2, in queste donne si è rilevato una alto tasso di supporto sociale percepito, in particolare ricevuto dalla persona di riferimento. L’area rivelatasi più critica nel supporto sociale è quella degli amici. Per quanto riguarda l’immagine corporea, la porzione di campione dai 30 ai 61 anni, ha delle preoccupazioni globali legate all’immagine corporea paragonabili ai dati provenienti dalla popolazione generale con preoccupazioni riguardo l’aspetto corporeo. Invece, nella porzione di campione dai 61 anni in su, il pattern di disagio verso l’aspetto fisico sembra decisamente peggiorare. Inoltre, in questo campione, si è rilevato un disagio globale verso l’immagine corporea significativamente più alto rispetto ai valori normativi presenti in letteratura riferiti a donne con cancro al seno con o senza mastectomia (rispettivamente t(94)= -4.78; p<0.000001; t(110)= -6.81;p<0.000001). La strategia di coping più utilizzata da queste donne è lo spirito combattivo, seguito dal fatalismo. Questo campione riporta, inoltre, una Qualità della Vita complessivamente soddisfacente, con un buon livello di funzionamento sociale. L’area di funzionalità più critica risulta essere il funzionamento emotivo. Considerando i sintomi prevalenti, i più riferiti sono affaticamento, disturbi del sonno e dolore. Per definire, invece, il pattern HRV, sono stati confrontati i dati del campione con quelli presenti in letteratura, riguardanti donne con cancro ovarico. Il campione valutato in questo studio, ha un HRV SDNN (Me=28.2ms) significativamente più alto dell’altro gruppo. Tuttavia, confrontando il valore medio di questo campione con i dati normativi sulla popolazione sana (Me=50ms), i nostri valori risultano drasticamente più bassi. In ultimo, donne che hanno ricevuto diagnosi di cancro ovarico in età fertile, sembrano avere maggiore HRV, migliore funzionamento emotivo e minore sintomatologia rispetto alle donne che hanno ricevuto diagnosi non in età fertile. Focalizzando l’attenzione sulla ricerca di relazioni significative tra le variabili in esame (obiettivo 3 e 4) sono state trovate numerose correlazioni significative tra: l’età e HRV, supporto percepito , Qualità della Vita; Qualità della Vita e immagine corporea, supporto sociale, strategie di coping; strategie di coping e immagine corporea, supporto sociale; immagine corporea e supporto sociale; HRV e supporto sociale, Qualità della Vita. Per verificare la possibile connessione causale tra le variabili considerate, sono state applicate regressioni lineari semplici e multiple per verificare la bontà del modello teorico. Si è rilevato che HRV è significativamente positivamente influenzata dal supporto percepito dalla figura di riferimento, dal funzionamento di ruolo, dall’immagine corporea totale. Invece risulta negativamente influenzata dal supporto percepito dagli amici e dall’uso di strategie di coping evitanti . La qualità della vita è positivamente influenzata da: l’immagine corporea globale e l’utilizzo del fatalismo come strategia di coping prevalente. Il funzionamento emotivo è influenzato dal supporto percepito dalla figura di riferimento e dal fatalismo. DISCUSSIONI E CONCLUSIONI: Il campione Italiano valutato, sembra essere a metà strada nell’adattamento dello stato psicologico e dell’equilibrio neurovegetativo al cancro. Sicuramente queste donne vivono una vita accettabile, in quanto sopravvissute al cancro, ma sembra anche che portino con sé preoccupazioni e difficoltà, in particolare legate all’accettazione della loro condizione di sopravvissute. Infatti, il migliore adattamento si riscontra nelle donne che hanno avuto peggiori condizioni in partenza: stadio del cancro avanzato, più giovani, con diagnosi ricevuta in età fertile. Pertanto, è possibile suggerire che queste condizioni critiche forzino queste donne ad affrontare apertamente il cancro e la loro situazione di sopravvissute al cancro, portandole ad “andare avanti” piuttosto che “tornare indietro”. Facendo riferimento alle connessioni tra variabili psicologiche e fisiologiche in queste donne, si è evidenziato che HRV è influenzata dalla presenza di figure significative ma, in particolare, è presumibile che sia influenzata da un’appropriata condivisione emotiva con queste figure. Si è anche evidenziato che poter continuare ad essere efficaci nel proprio contesto personale si riflette in un maggiore HRV, probabilmente in quanto permette di preservare il senso di sé, riducendo in questo modo lo stress derivante dall’esperienza cancro. Pertanto, HRV in queste donne risulta associato con un migliore adattamento psicologico. Inoltre, si è evidenziato che in queste donne la Qualità della Vita è profondamente influenzata dalla percezione dell’immagine corporea. Si tratta di un aspetto innovativo che è stato rilevato in questo campione e che, invece, nei precedenti studi non è stato indagato. In ultimo, la strategia di coping fatalismo sembra essere protettiva e sembra facilitare il processo di accettazione del cancro. Si spera sinceramente che le ricerche future possano superare i limiti del presente studio, come la scarsa numerosità e l’uso di strumenti di valutazione che, per alcuni aspetti come la scala Evitamento nel MAC, non centrano totalmente il target di indagine. Le traiettorie future di questo studio sono: aumentare il numero di osservazioni, reclutando donne in diversi centri specialistici in diverse zone d’Italia; utilizzare strumenti più specifici per valutare i costrutti in esame; valutare se un intervento di supporto centrato sul miglioramento di HRV (come HRV Biofeedback) può avere una ricaduta positiva sull’adattamento emotivo e la Qualità della Vita.
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Employment generating public works (EGPW) are an important part of Royal Government of Cambodia’s (RGC’s) strategy being developed through Council for Agriculture and Rural Development (CARD) to develop a comprehensive social safety net (SSN) to provide a measure of protection from shocks for the poor and vulnerable and to contribute to poverty alleviation through short-term unskilled employment.
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Several life history traits of sharks result in juveniles being particularly vulnerable to exploitation. However, population level impacts of harvests on juvenile sharks have not been well quantified. This paper examines a range of harvest strategies, including those targeting juveniles. Reproductive value and yield per recruit are used to compare the harvests, which are represented by Leslie matrix models with a harvest matrix. Two species are used as examples: the short-lived Rhizoprionodon taylori and the long-lived Squalus acanthias. Harvests that maintain a stationary population size cause reproductive values to change in opposing ways, but they remove equal fractions of the population's reproductive potential. A new theorem gives population growth as a function of the fraction of reproductive potential removed by a harvest, a relationship useful for comparing harvests on juveniles and adults. Stochastic projections indicate that the risk of depletion is associated with the fraction of reproductive potential removed annually, a measure which encompasses the information in both the selectivity and the rate of fishing mortality. These results indicate the value of focusing conservation efforts on preserving reproductive potential.
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The present trail aimed to study the effect of crossbreeding between Alentejano (AL) and Bísaro (BI) swine breeds (“Ribatejano pig”) on some reproductive and productive traits. Nine AL gilts and sows and six BI gilts were crossed with BI and AL boars, respectively. Mating and farrowing dates, prolificacy and litter size at 28d were registered for all sows. The pregnancy length of AL sows was shorter (111±0.4d vs 113.7±0.5d; p=0.002) than the observed on BI females. The BI gilts presented higher prolificacy rate than AL on both total born (11.0±1.0 vs 6.7±0.8; P=0.004) and born alive piglets (10.0±1.0 vs 6.7±0.8; p=0.026). The mortality rate was similar in both genotypes (p=0.255) being on average 12%, therefore at 28d after farrowing the litter size remained higher in BI sows (8.5±0.8 vs 6.1±0.6; p= 0.032). A subset of each genotype (4 gilts) was supervised during farrowing and lactation (until 28d) and piglets were weighed at birth, 24h and 28d of live. Farrowing length was not significantly different (p=0.253) between genotypes, averaging 97±22 min. When compared to ALBI (AL x BI) piglets, the BIAL (BI x AL) piglets were heavier at birth (1402±46g vs 1209±36g; p=0.002). Colostrum intake of piglets per kg of birth weight on the first 24h of life was similar between genotypes (p=0.735) being 289±15g for ALBI and 281±19g for BIAL piglets. The growth rate of piglets from birth to 28d and piglet weight at 28d was not different between genotypes (p=0.161 and p=0.091) averaging 195±6g and 6761±181g, respectively. Litter weight at 28d tended (P=0.06) to be higher on ALBI litters (56.6±4.0kg) than BIAL litters (43.2±4.0kg). This results obtained within the frame of Treasure project* are, at our knowledge, the first data of these crossbred piglets and could be used in future as reference for further studies and also for farmers that may try these cross on a commercial basis.
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This paper introduces an energy-efficient Rate Adaptive MAC (RA-MAC) protocol for long-lived Wireless Sensor Networks (WSN). Previous research shows that the dynamic and lossy nature of wireless communication is one of the major challenges to reliable data delivery in a WSN. RA-MAC achieves high link reliability in such situations by dynamically trading off radio bit rate for signal processing gain. This extra gain reduces the packet loss rate which results in lower energy expenditure by reducing the number of retransmissions. RA-MAC selects the optimal data rate based on channel conditions with the aim of minimizing energy consumption. We have implemented RA-MAC in TinyOS on an off-the-shelf sensor platform (TinyNode), and evaluated its performance by comparing RA-MAC with state-ofthe- art WSN MAC protocol (SCP-MAC) by experiments.
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Ongoing problems exist with the commercial scale domestication of Penaeus monodon. One of the major issues, in terms of reproductive performance, is the low egg hatch rate of eggs from these captive bred prawns. The current study investigated the related issue of mating success. Time lapse video observations were conducted to compare the mating behaviour of pond-reared (domesticated) and wild-caught prawn P. monodon broodstock. Mating success of the pond-reared prawns was found to be low relative to wild-caught. It was determined that both male and female prawns contributed to this low mating rate suggesting both genders were impacted negatively by the domestication process. The causative factors for the low mating success are yet to be determined, however external physical abnormalities and lack of sexual maturity did not appear to play a role. The most notable behavioural difference between wild-caught and domesticated prawns was a reduced level of pursuit behaviour by domesticated males. This and other behavioural differences are discussed in relation to an increasing body of evidence that male prawns respond to sex pheromones produced by receptive females and that males detect these chemical signals in part, via their second antennal flagella. Accordingly we hypothesise that pond-reared (domesticated) females may have a reduced ability to produce or release sex pheromones and males, a reduced ability to detect them when compared to their wild-caught counterparts.
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With the advent of functional neuroimaging techniques, in particular functional magnetic resonance imaging (fMRI), we have gained greater insight into the neural correlates of visuospatial function. However, it may not always be easy to identify the cerebral regions most specifically associated with performance on a given task. One approach is to examine the quantitative relationships between regional activation and behavioral performance measures. In the present study, we investigated the functional neuroanatomy of two different visuospatial processing tasks, judgement of line orientation and mental rotation. Twenty-four normal participants were scanned with fMRI using blocked periodic designs for experimental task presentation. Accuracy and reaction time (RT) to each trial of both activation and baseline conditions in each experiment was recorded. Both experiments activated dorsal and ventral visual cortical areas as well as dorsolateral prefrontal cortex. More regionally specific associations with task performance were identified by estimating the association between (sinusoidal) power of functional response and mean RT to the activation condition; a permutation test based on spatial statistics was used for inference. There was significant behavioral-physiological association in right ventral extrastriate cortex for the line orientation task and in bilateral (predominantly right) superior parietal lobule for the mental rotation task. Comparable associations were not found between power of response and RT to the baseline conditions of the tasks. These data suggest that one region in a neurocognitive network may be most strongly associated with behavioral performance and this may be regarded as the computationally least efficient or rate-limiting node of the network.
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Captive-reared broodstock of the black tiger prawn (Penaeus monodon) have exhibited poor reproductive performance limiting attempts to domesticate this species. The potential for improved reproductive performance was assessed by determining heritabilities of four measures of reproductive performance, their genetic correlations with each other and with growth rate and weight at age. Heritability estimates (h2 ± S.E.) obtained from √ (days to spawn), √ (egg number), √ (nauplii number) and arcsin √ (proportion hatched) were 0.47 ± 0.15, 0.41 ± 0.18, 0.27 ± 0.16, and 0.18 ± 0.16, respectively. Estimates of genetic correlations between reproductive traits and weight at age, or growth rate were less than 0.5 except for √ (egg number) and weight at 54 weeks (0.93 ± 0.19) and √ (egg number) and 16-54-week growth (0.63 ± 0.29).
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We investigated aspects of the reproductive ecology of Ochna serrulata (Hochst.) Walp., an invasive plant in eastern Australia. O. serrulata drupes were similar in size to fleshy fruits of other local invasive plants, but showed some distinct differences in quality, with a very high pulp lipid content (32.8% of dry weight), and little sugar and water. Seeds were dispersed by figbirds, Sphecotheres viridis Vieillot, a locally abundant frugivore, and comprised between 10 and 50% of all non-Ficus spp. fruit consumed during October and November. The rate of removal of O. serrulata drupes was greater in bushland than suburban habitats, indicating that control in bushland habitats should be a priority, but also that suburban habitats are likely to act as significant seed sources for reinvasion of bushland. Germination occurred under all seed-processing treatments (with and without pulp, and figbird gut passage), suggesting that although frugivores are important for dispersal, they are not essential for germination. Recruitment of buried and surface-sown seed differed between greenhouse and field experiments, with minimal recruitment of surface-sown seed in the field. Seed persistence was low, particularly under field conditions, with 0.75% seed viability after 6 months and 0% at 12 months. This provides an opportunity to target control efforts in south-eastern Queensland in spring before fruit set, when there is predicted to be few viable seeds in the soil.
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A review of factors that may impact on the capacity of beef cattle females, grazing semi-extensive to extensive pastures in northern Australia, to conceive, maintain a pregnancy and wean a calf was conducted. Pregnancy and weaning rates have generally been used to measure the reproductive performance of herds. However, this review recognises that reproductive efficiency and the general measures associated with it more effectively describe the economic performance of beef cattle enterprises. More specifically, reproductive efficiency is influenced by (1) pregnancy rate which is influenced by (i) age at puberty; (ii) duration of post-partum anoestrus; (iii) fertilisation failure and (iv) embryo survival; while (2) weight by number of calves per breeding female retained for mating is influenced by (i) cow survival; (ii) foetal survival; and (iii) calf survival; and (3) overall lifetime calf weight weaned per mating. These measures of reproductive efficiency are discussed in depth. Further, a range of infectious and non-infectious factors, namely, environmental, physiological, breed and genetic factors and their impact on these stages of the reproductive cycle are investigated and implications for the northern Australian beef industry are discussed. Finally, conclusions and recommendations to minimise reproductive inefficiencies based on current knowledge are presented.
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Early-in-life female and male measures with potential to be practical genetic indicators were chosen from earlier analyses and examined together with genomic measures for multi-trait use to improve female reproduction of Brahman cattle. Combinations of measures were evaluated on the genetic gains expected from selection of sires and dams for each of age at puberty (AGECL, i.e. first observation of a corpus luteum), lactation anoestrous interval in 3-year-old cows (LAI), and lifetime annual weaning rate (LAWR, i.e. the weaning rate of cows based on the number of annual matings they experienced over six possible matings). Selection was on an index of comparable records for each combination. Selection intensities were less than theoretically possible but assumed a concerted selection effort was able to be made across the Brahman breed. The results suggested that substantial genetic gains could be possible but need to be confirmed in other data. The estimated increase in LAWR in 10 years, for combinations without or with genomic measures, ranged from 8 to 12 calves weaned per 100 cows from selection of sires, and from 12 to 15 calves weaned per 100 cows from selection of sires and dams. Corresponding reductions in LAI were 60-103 days or 94-136 days, and those for AGECL were 95-125 or 141-176 days, respectively. Coat score (a measure of the sleekness or wooliness of the coat) and hip height in females, and preputial eversion and liveweight in males, were measures that may warrant wider recording for Brahman female reproduction genetic evaluation. Pregnancy-test outcomes from Matings 1 and 2 also should be recorded. Percentage normal sperm may be important to record for reducing LAI and scrotal size and serum insulin-like growth factor-I concentration in heifers at 18 months for reducing AGECL. Use of a genomic estimated breeding value (EBV) in combination with other measures added to genetic gains, especially at genomic EBV accuracies of 40%. Accuracies of genomic EBVs needed to approach 60% for the genomic EBV to be the most important contributor to gains in the combinations of measures studied.
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Objective To compare reproduction in extensively managed, tropically adapted beef cows that were either seropositive or seronegative to Neospora caninum. Design Longitudinal study of cows within management groups. Methods Compare pregnancy with weaning outcomes for 502 seropositive and 3255 seronegative cows in 25 management groups. Results We found N. caninum in all herds, with an average of 20% of 2640 tested animals seropositive within management group; prevalence varied between 0% and 94%. At 7 of 10 sites assessed, there was evidence of horizontal transmission of N. caninum. There was no overall difference in pregnancy rate (79% vs 75%; P > 0.05), reproductive wastage after confirmed pregnancy diagnosis (11% vs 10%; P > 0.05) or weaning rate (67% vs 68%; P > 0.05) between seronegative and seropositive cows, respectively. In one herd where a combination of risk factors for N. caninum was present, a significant reduction in pregnancy rate occurred after the 6 months mating (85% vs 69%; P < 0.05). The fetal and calf losses observed were lowest in south-east Queensland (4.3% of 117 pregnancies), highest in north-west Queensland (15.5% of 413 pregnancies) and intermediate in north-east Queensland (10.2% of 1625 pregnancies). Other infectious agents that are known to cause reproductive wastage were endemic in many herds, though none appeared to cause significant fetal or calf loss in this study. Conclusion Despite a high prevalence of N. caninum, there was no apparent effect on beef cattle reproduction, but there is potential to cause reproductive wastage if known risk factors to neosporosis are in effect.