scholarly journals Reburial potential and survivability of the striped venus clam (Chamelea gallina) in hydraulic dredge fisheries

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Giada Bargione ◽  
Andrea Petetta ◽  
Claudio Vasapollo ◽  
Massimo Virgili ◽  
Alessandro Lucchetti

AbstractThe striped venus clam (Chamelea gallina) is the main edible bivalve living in Italian waters. According to Regulation (EU) 2020/2237, undersized specimens (total length of the shell, < 22 mm) must be returned to the sea. C. gallina specimens of different size classes that had undergone hydraulic dredging and mechanized sorting were analysed for reburial ability in a laboratory tank and for survivability in the laboratory (135 clams, 21 days) and at sea (320 clams, 15 days). In the tank experiments, the reburial times (T50 and T90) and the upper (+) and lower (−) confidence intervals (CIs) of the whole sample were about 4 h (CI+ 4.4, CI− 3.6) and 8 h (CI+ 8.2, CI− 7.7), respectively, and were significantly shorter for the medium-sized clams (22–24.9 mm) than for the smallest (< 21.9 mm) and the largest (> 25 mm) specimens. For the field survivability experiments, clams under and above the minimum conservation reference size were placed in separate metal cages. Survival rates were 94.8% and 96.2% respectively in the laboratory and at sea, without significant differences between the two experiments or among size classes. These findings conclusively demonstrate that C. gallina specimens returned to the sea have a very high survival probability and that they can contribute to mitigate the overexploitation of natural populations.

Author(s):  
Domenico Nicolò

Although young firms are very vulnerable, significant differences emerge by comparing the survival rates of the companies in the first stage of life in different countries and industries, of different sizes, and with different characteristics of the leader (team of co-founders): education, previous entrepreneurial experience, reputation, etc. Many variables influence the performance of the companies and their chances of survival. Each enterprise is a singularity. Thus, it is methodologically wrong and naive any attempt to define ideal models and general “recipes” to reduce the vulnerability of the young firms. This hypothesis is confirmed by the analysis of the survival rates of the young firms born in the USA and in EU. The variance of the five-year survival rate is very high by comparing companies from different nations, of different size classes, those operating in different industries, and those whose leaders have or not have any previous entrepreneurial experience. The lack of corporate reputation is the only weakness common to the young firms. Since these companies do not have a history that can prove their ability to satisfy their commitments toward the stakeholder, they haven't a reputation and therefore are very weak their bonds of trust with stakeholders. The first difficulty, these weak bonds of trust are broken and young businesses collapse in on themselves. To achieve sustainability, young firms must quickly build a corporate reputation to strengthen the bonds of trust with the stakeholders. By this way, they will be more resistant to the difficulties. This is the only effective general “recipes”. (Nicolò 2015; Nicolò & Ferrara 2015).


2015 ◽  
Vol 42 (5) ◽  
pp. 454 ◽  
Author(s):  
Michael L. Casazza ◽  
Peter S. Coates ◽  
Cory T. Overton ◽  
Kristy B. Howe

Context The band-tailed pigeon (Patagioenas fasciata) is a migratory species occurring in western North America with low recruitment potential and populations that have declined an average of 2.4% per year since the 1960s. Investigations into band-tailed pigeon demographic rates date back to the early 1900s, and existing annual survival rate estimates were derived in the 1970s using band return data. Aims The primary purpose of the paper was to demonstrate that the apparent paradox between band-tailed pigeon population dynamics (long-term steady decline) and breeding season survival rates (very high) can be explained by changes in survival probability during the remainder of the year. Methods We trapped Pacific coast band-tailed pigeons during two separate periods: we equipped pigeons with very high frequency (VHF) radio-transmitters in 1999–2000 (1999 = 20; 2000 = 34); and outfitted pigeons with solar powered platform transmitting terminal (PTT) transmitters in 2006–08 (n = 20). We used known fate models to estimate annual survival rates and seasonal survival variation among four periods based on an annual behavioural cycle based on phenological events (nesting, autumn migration, winter and spring migrations). We used model averaged parameter estimates to account for model selection uncertainty. Key results Neither body condition nor sex were associated with variation in band-tailed pigeon survival rates. Weekly survival during the nesting season did not differ significantly between VHF-marked (0.996; CI = 0.984–0.999) and PTT-marked pigeons (0.998; CI = 0.990–1.00). Model averaged annual survival of PTT-marked pigeons was 0.682 (95% CI = 0.426–0.861) and was similar to annual survival estimated in previous studies using band return data. Survival probability was lowest during both migration periods and highest during the nesting period. Conclusions Our survival estimates are consistent with those of prior studies and suggest that mortality risk is greatest during migration. Weekly survival probability during winter was nearly the same as during the nesting season; however, winter was the longest period and survival throughout winter was lower than other seasons. Implications We present the first inter-seasonal analysis of survival probability of the Pacific coast race of band-tailed pigeons and illustrate important temporal patterns that may influence future species management including harvest strategies and disease monitoring.


BMJ Open ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. e043844
Author(s):  
Natalia Araujo ◽  
Samantha Morais ◽  
Ana Rute Costa ◽  
Raquel Braga ◽  
Ana Filipa Carneiro ◽  
...  

IntroductionProstate cancer is the most prevalent oncological disease among men in industrialised countries. Despite the high survival rates, treatments are often associated with adverse effects, including metabolic and cardiovascular complications, sexual dysfunction and, to a lesser extent, cognitive decline. This study was primarily designed to evaluate the trajectories of cognitive performance in patients with prostate cancer, and to quantify the impact of the disease and its treatments on the occurrence of cognitive decline.MethodsParticipants will be recruited from two main hospitals providing care to approximately half of the patients with prostate cancer in Northern Portugal (Portuguese Institute of Oncology of Porto and São João Hospital Centre), and will comprise a cohort of recently diagnosed patients with prostate cancer proposed for different treatment plans, including: (1) radical prostatectomy; (2) brachytherapy and/or radiotherapy; (3) radiotherapy in combination with androgen deprivation therapy and (4) androgen deprivation therapy (with or without chemotherapy). Recruitment began in February 2018 and is expected to continue until the first semester of 2021. Follow-up evaluations will be conducted at 1, 3, 5, 7 and 10 years. Sociodemographic, behavioural and clinical characteristics, anxiety and depression, health literacy, health status, quality of life, and sleep quality will be assessed. Blood pressure and anthropometrics will be measured, and a fasting blood sample will be collected. Participants’ cognitive performance will be evaluated before treatments and throughout follow-up (Montreal Cognitive Assessment and Cube Test as well as Brain on Track for remote monitoring). All participants suspected of cognitive impairment will undergo neuropsychological tests and clinical observation by a neurologist.Ethics and disseminationThe study was approved by the Ethics Committee of the hospitals involved. All participants will provide written informed consent, and study procedures will be developed to ensure data protection and confidentiality. Results will be disseminated through publication in peer-reviewed journals and presentation in scientific meetings.


2019 ◽  
Vol 47 (5) ◽  
pp. 1307-1325 ◽  
Author(s):  
Caroline Busch ◽  
Helen Wheadon

Abstract Chronic myeloid leukaemia (CML) is a paradigm of precision medicine, being one of the first cancers to be treated with targeted therapy. This has revolutionised CML therapy and patient outcome, with high survival rates. However, this now means an ever-increasing number of patients are living with the disease on life-long tyrosine kinase inhibitor (TKI) therapy, with most patients anticipated to have near normal life expectancy. Unfortunately, in a significant number of patients, TKIs are not curative. This low-level disease persistence suggests that despite a molecularly targeted therapeutic approach, there are BCR-ABL1-independent mechanisms exploited to sustain the survival of a small cell population of leukaemic stem cells (LSCs). In CML, LSCs display many features akin to haemopoietic stem cells, namely quiescence, self-renewal and the ability to produce mature progeny, this all occurs through intrinsic and extrinsic signals within the specialised microenvironment of the bone marrow (BM) niche. One important avenue of investigation in CML is how the disease highjacks the BM, thereby remodelling this microenvironment to create a niche, which enables LSC persistence and resistance to TKI treatment. In this review, we explore how changes in growth factor levels, in particular, the bone morphogenetic proteins (BMPs) and pro-inflammatory cytokines, impact on cell behaviour, extracellular matrix deposition and bone remodelling in CML. We also discuss the challenges in targeting LSCs and the potential of dual targeting using combination therapies against BMP receptors and BCR-ABL1.


2020 ◽  
Vol 9 (12) ◽  
pp. 3943
Author(s):  
João Caramês ◽  
Ana Catarina Pinto ◽  
Gonçalo Caramês ◽  
Helena Francisco ◽  
Joana Fialho ◽  
...  

This retrospective study evaluated the survival rate of short, sandblasted acid-etched surfaced implants with 6 and 8 mm lengths with at least 120 days of follow-up. Data concerning patient, implant and surgery characteristics were retrieved from clinical records. Sandblasted and acid-etched (SLA)-surfaced tissue-level 6 mm (TL6) or 8 mm (TL8) implants or bone-level tapered 8 mm (BLT8) implants were used. Absolute and relative frequency distributions were calculated for qualitative variables and mean values and standard deviations for quantitative variables. A Cox regression model was performed to verify whether type, length and/or width influence the implant survival. The cumulative implant survival rate was assessed by time-to-event analyses (Kaplan–Meier estimator). In all, 513 patients with a mean age of 58.00 ± 12.44 years received 1008 dental implants with a mean follow-up of 21.57 ± 10.77 months. Most implants (78.17%) presented a 4.1 mm diameter, and the most frequent indication was a partially edentulous arch (44.15%). The most frequent locations were the posterior mandible (53.97%) and the posterior maxilla (31.55%). No significant differences were found in survival rates between groups of type, length and width of implant with the cumulative rate being 97.7% ± 0.5%. Within the limitations of this study, the evaluated short implants are a predictable option with high survival rates during the follow-up without statistical differences between the appraised types, lengths and widths.


1992 ◽  
Vol 70 (4) ◽  
pp. 820-824 ◽  
Author(s):  
David O. Ribble ◽  
John S. Millar

We examined the effects of sibling matings upon reproductive performance among inbred and outbred laboratory colonies of Peromyscus maniculatus. The inbred colony was founded by 12 females collected from one locality in Alberta and bred for 20 generations, with 35–45 pairs each generation. The outbred colony consisted of first-generation mice born of wild-caught females from diverse areas in Alberta. Consistent with theoretical expectations, there were no differences in reproductive performance between sibling and control (outbred) pairs within the inbred colony of mice. In contrast, sibling pairs had significantly fewer young per litter than control pairs within the outbred colony. Reproductive performance measures (proportion breeding, days from pairing to first litter, number of litters, and total number of offspring produced) were also significantly lower among sibling pairs from the outbred colony than among sibling pairs from the inbred colony. Lastly, we predicted that reproductive performance of the control pairs from the outbred colony would be less than that of control pairs from the inbred colony, due to outbreeding depression. Contrary to our predictions, average litter survival rates were greatest among the outbred colony control pairs. We suggest that the benefits of inbreeding or outbreeding extend broadly across the inbreeding–outbreeding continuum in natural populations of northern Peromyscus.


2015 ◽  
Vol 45 (12) ◽  
pp. 1728-1738 ◽  
Author(s):  
Christopher E. Looney ◽  
Anthony W. D’Amato ◽  
Brian J. Palik ◽  
Robert A. Slesak

Fraxinus nigra Marsh. (black ash) wetland forests in northern Minnesota, USA, are threatened by the invasive insect, emerald ash borer (Agrilus planipennis Fairmaire (EAB)). A potential management option is promoting regeneration of tree species that are not EAB hosts to maintain ecosystem functions. Using an operational-scale field experiment, we examined the survival of 12 alternative tree species in response to different canopy treatments. We planted the seedlings in 1.6 ha plots assigned to four replicated canopy treatments: untreated control, group selection (0.04 ha gaps, 20% of stand), black ash girdling to emulate EAB-induced mortality, and clearcut. Fall and spring plantings were used to compare the effects of spring ponding. Control (32.9%), group selection (34.5%), and girdling (33.3%) treatments had comparable overall seedling survival. Survival in the clear-cut treatments was significantly lower (22%). Species selection, overstory treatment, and season of planting together resulted in survival rates ranging from 0.08% to 94.1%. Conifer species had low overall rates of survival (10.7%), whereas some species with native ranges not presently overlapping with northern F. nigra forests, e.g., Quercus bicolor Willd. (75.5%), had high survival rates. If growth is light-limited, group selection may be effective in promoting recruitment and supporting a larger variety of species.


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