Effects of drought on weight, survival and breeding success of agile antechinus (Antechinus agilis), dusky antechinus (A. swainsonii) and bush rats (Rattus fuscipes)

2007 ◽  
Vol 34 (6) ◽  
pp. 437 ◽  
Author(s):  
Marissa L. Parrott ◽  
Simon J. Ward ◽  
Peter D. Temple-Smith ◽  
Lynne Selwood
Keyword(s):  
Breeding Season ◽  
Breeding Success ◽  
Survival Rates ◽  
Weather Conditions ◽  
High Survival ◽  
Limited Information ◽  
Pregnancy And Lactation ◽  
Antechinus Agilis ◽  
Rattus Fuscipes ◽  
Effects Of Drought

Extreme weather conditions, such as drought, significantly decrease the survival and breeding success of numerous species. Despite the frequent occurrence of such conditions in Australia, little is known about the effects of changing environmental conditions on the native small mammals. This study, conducted from 2002 to 2004, focussed on sympatric wild populations of the agile antechinus (Antechinus agilis), with more limited information on the dusky antechinus (A. swainsonii) and the bush rat (Rattus fuscipes). Bodyweights of agile antechinus before and during the breeding season were significantly lower in 2003 (drought) than in 2002 or 2004. Survival of female agile antechinus and the number of young per litter also decreased significantly during drought. In contrast, the dusky antechinus showed no difference in mean bodyweights between years, high survival rates of females and similar litter sizes in 2002 and 2003. There was also no difference in bodyweight of bush rats between years. Low rainfall was recorded during pregnancy and lactation in the agile antechinus, but rainfall was higher during pregnancy and lactation in the dusky antechinus. The survival and breeding success of the agile antechinus may have been adversely affected by a combination of interspecific competition, timing of the breeding season and severity of the drought.

scholarly journals The Red Harmful Plague in Times of Climate Change: Blooms of the Cyanobacterium Planktothrix rubescens Triggered by Stratification Dynamics and Irradiance

2021 ◽  
Vol 12 ◽  
Author(s):  
Deborah Knapp ◽  
Bieito Fernández Castro ◽  
Daniel Marty ◽  
Eugen Loher ◽  
Oliver Köster ◽  
...  
Keyword(s):  
Thermal Stratification ◽  
Survival Rates ◽  
Standing Stock ◽  
Keystone Species ◽  
Weather Conditions ◽  
High Survival ◽  
Negative Consequences ◽  
Planktothrix Rubescens ◽  
Water Column Stability ◽  
Long Term Study

Planktothrix rubescens is a harmful planktonic cyanobacterium, forming concentrated metalimnetic populations in deep oligo- and mesotrophic lakes, even after successful restoration. In Lake Zurich (Switzerland), P. rubescens emerged as a keystone species with annual mass developments since the 1970s. Its success was partly attributed to effects of lake warming, such as changes in thermal stratification and seasonal deep mixing. However, recent observations based on a biweekly monitoring campaign (2009–2020) revealed two massive breakdowns and striking seasonal oscillations of the population. Here, we disentangle positive from negative consequences of secular lake warming and annual variations in weather conditions on P. rubescens dynamics: (i) despite the high survival rates of overwintering populations (up to 25%) during three consecutive winters (2014–2016) of incomplete deep convective mixing, cyanobacterial regrowth during the following stratified season was moderate and not overshooting a distinct standing stock threshold. Moreover, we recorded a negative trend for annual population maxima and total population size, pointing to a potential nutrient limitation after a series of incomplete winter mixing. Thus, the predication of steadily increasing blooms of P. rubescens could not be confirmed for the last decade. (ii) The seasonal reestablishment of P. rubescens was strongly coupled with a timely formation of a stable metalimnion structure, where the first positive net growth in the following productive summer season was observed. The trigger for the vertical positioning of filaments within the metalimnion was irradiance and not maximal water column stability. Repetitive disruptions of the vernal metalimnion owing to unstable weather conditions, as in spring 2019, went in parallel with a massive breakdown of the standing stock and marginal regrowth during thermal stratification. (iii) Driven by light intensity, P. rubescens was entrained into the turbulent epilimnion in autumn, followed by a second peak in population growth. Thus, the typical bimodal growth pattern was still intact during the last decade. Our long-term study highlights the finely tuned interplay between climate-induced changes and variability of thermal stratification dynamics and physiological traits of P. rubescens, determining its survival in a mesotrophic temperate lake.

scholarly journals Efficient UAV Path Planning with Multiconstraints in a 3D Large Battlefield Environment

2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
Weiwei Zhan ◽  
Wei Wang ◽  
Nengcheng Chen ◽  
Chao Wang
Keyword(s):  
Path Planning ◽  
Detection Probability ◽  
Large Scale ◽  
Optimal Path ◽  
Survival Rates ◽  
Weather Conditions ◽  
Target Space ◽  
High Survival ◽  
Turning Radius ◽  
Battlefield Environment

This study introduces an improvedA*algorithm for the real-time path planning of Unmanned Air Vehicles (UAVs) in a 3D large-scale battlefield environment to solve the problem that UAVs require high survival rates and low fuel consumption. The algorithm is able to find the optimal path between two waypoints in the target space and comprehensively takes factors such as altitude, detection probability, and path length into account. It considers the maneuverability constraints of the UAV, including the safety altitude, climb rate, and turning radius, to obtain the final flyable path. Finally, the authors test the algorithm in an approximately 2,500,000 square meter area containing radars, no-fly zones, and extreme weather conditions to measure its feasibility, stability, and efficiency.

scholarly journals Selection of Calf Bedding Sites by Female Elk in the Central Appalachian Mountains

2019 ◽  
Vol 10 (1) ◽  
pp. 91-101
Author(s):  
Joseph E. Duchamp ◽  
Melia T. DeVivo ◽  
Jon M. DeBerti ◽  
Lindsey M. Heffernan ◽  
Jason D. Kougher ◽  
...  
Keyword(s):  
Habitat Management ◽  
Spatial Scales ◽  
Survival Rates ◽  
Coniferous Forest ◽  
Appalachian Mountains ◽  
Landscape Scale ◽  
Local Scale ◽  
High Survival ◽  
Limited Information ◽  
Lactating Females

Abstract Across eastern North America, Rocky Mountain elk Cervus canadensis nelsoni have been reintroduced to 11 states and provinces that were previously occupied by the extinct eastern elk C. canadensis canadensis. Outside of Kentucky, these elk reintroductions have resulted in small populations, typically numbering fewer than 1,000 elk per state. Limited information is available about the demographics and habitat selection within these small eastern populations. The availability of high-quality habitat during the first weeks of life is important for promoting annual recruitment and the identification of these characteristics should aid in management efforts. We characterized habitat at two spatial scales surrounding the bedding sites of 83 elk calves (≤ 7 d old) in the Pennsylvania Elk Management Area during the annual calving seasons of 2005–2008. A concurrent study found that calves in this area experienced high survival (92%) during the first 4 mo of life, despite occupying an area with high predator densities. At a local scale, bedding sites used by calves were closer to ecotones, had less leaf litter, and had greater density of vegetation below 1 m compared to random sites (n = 82). At a landscape scale, calf habitat surrounding bedding sites had greater density of edges between forest and open vegetation and less coniferous forest compared to random areas. The selected habitats appear to balance the high energetic needs of lactating females at the landscape scale and the need for cover to conceal calves and reduce predation risk at a local scale. Conclusions drawn from our models suggest future habitat management include enhancements of transitional vegetation along ecotones between forest and herbaceous openings that address the needs of both lactating females and recently born calves. We recommend that managers periodically evaluate the availability of calf habitat and calf survival rates. These monitoring activities will provide insight necessary to adaptively manage elk and the habitats driving their population growth to maintain their viability in the central Appalachian Mountains.

scholarly journals Cognitive decline in patients with prostate cancer: study protocol of a prospective cohort, NEON-PC

BMJ Open ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. e043844
Author(s):  
Natalia Araujo ◽  
Samantha Morais ◽  
Ana Rute Costa ◽  
Raquel Braga ◽  
Ana Filipa Carneiro ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Cognitive Decline ◽  
Cognitive Performance ◽  
Androgen Deprivation Therapy ◽  
Survival Rates ◽  
Cardiovascular Complications ◽  
Androgen Deprivation ◽  
High Survival ◽  
The Impact

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.

scholarly journals Bone marrow niche crosses paths with BMPs: a road to protection and persistence in CML

2019 ◽  
Vol 47 (5) ◽  
pp. 1307-1325 ◽  
Author(s):  
Caroline Busch ◽  
Helen Wheadon
Keyword(s):  
Stem Cells ◽  
Bone Marrow ◽  
Bone Morphogenetic Proteins ◽  
Kinase Inhibitor ◽  
Survival Rates ◽  
High Survival ◽  
Bone Marrow Niche ◽  
Matrix Deposition ◽  
Bmp Receptors ◽  
Number Of Patients

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.

scholarly journals Survival Rate of 1008 Short Dental Implants with 21 Months of Average Follow-Up: A Retrospective Study

2020 ◽  
Vol 9 (12) ◽  
pp. 3943
Author(s):  
João Caramês ◽  
Ana Catarina Pinto ◽  
Gonçalo Caramês ◽  
Helena Francisco ◽  
Joana Fialho ◽  
...  
Keyword(s):  
Retrospective Study ◽  
Survival Rate ◽  
Dental Implants ◽  
Cox Regression ◽  
Survival Rates ◽  
High Survival ◽  
Implant Survival ◽  
Posterior Maxilla ◽  
Clinical Records

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.

scholarly journals Weather conditions explain reproductive success and advancement of the breeding season in Western Capercaillie ( Tetrao urogallus )

Ibis ◽  
2021 ◽  
Author(s):  
Joy Coppes ◽  
Jim‐Lino Kämmerle ◽  
Karl‐Eugen Schroth ◽  
Veronika Braunisch ◽  
Rudi Suchant
Keyword(s):  
Reproductive Success ◽  
Breeding Season ◽  
Weather Conditions ◽  
Tetrao Urogallus

Overstory treatment and planting season affect survival of replacement tree species in emerald ash borer threatened Fraxinus nigra forests in Minnesota, USA

2015 ◽  
Vol 45 (12) ◽  
pp. 1728-1738 ◽  
Author(s):  
Christopher E. Looney ◽  
Anthony W. D’Amato ◽  
Brian J. Palik ◽  
Robert A. Slesak
Keyword(s):  
Tree Species ◽  
Group Selection ◽  
Survival Rates ◽  
Emerald Ash Borer ◽  
Species Selection ◽  
Ecosystem Functions ◽  
Control Group ◽  
High Survival ◽  
Fraxinus Nigra ◽  
Black Ash

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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