Interspecific interactions, including predator–prey, intraguild predation (IGP) and competition, may drive distribution and habitat use of predator communities. However, elucidating the relative ...importance of these interactions in shaping predator distributions is challenging, especially in marine communities comprising highly mobile species.
We used individual‐based models (IBMs) to predict the habitat distributions of apex predators, intraguild (IG) prey and prey. We then used passive acoustic telemetry to test these predictions in a subtropical marine predator community consisting of eight elasmobranch (i.e. shark and ray) species in Bimini, The Bahamas.
IBMs predicted that prey and IG prey will preferentially select habitats based on safety over resources (food), with stronger selection for safe habitat by smaller prey. Elasmobranch space‐use patterns matched these predictions. Species with predator–prey and asymmetrical IGP (between apex and small mesopredators) interactions showed the clearest spatial separation, followed by asymmetrical IGP among apex and large mesopredators. Competitors showed greater spatial overlap although with finer‐scale differences in microhabitat use.
Our study suggests space‐use patterns in elasmobranchs are at least partially driven by interspecific interactions, with stronger spatial separation occurring where interactions include predator–prey relationships or IGP.
This paper uses individual‐based models and acoustic telemetry to investigate predator interactions in marine communities, offering insights into spatial distribution patterns of large‐bodied predators like sharks and rays. It addresses a significant knowledge gap, revealing how competition, predation and intraguild predation influence habitat preferences, crucial for marine ecology and conservation.
Diverse architectures of nervous systems (NSs) such as a plexus in cnidarians or a more centralized nervous system (CNS) in insects and vertebrates are present across Metazoa, but it is unclear what ...selection pressures drove evolution and diversification of NSs. One underlying aspect of this diversity lies in the cellular and molecular mechanisms driving neurogenesis, i.e. generation of neurons from neural precursor cells (NPCs). In cnidarians, vertebrates, and arthropods, homologs of SoxB and bHLH proneural genes control different steps of neurogenesis, suggesting that some neurogenic mechanisms may be conserved. However, data are lacking for spiralian taxa.
To that end, we characterized NPCs and their daughters at different stages of neurogenesis in the spiralian annelid Capitella teleta. We assessed cellular division patterns in the neuroectoderm using static and pulse-chase labeling with thymidine analogs (EdU and BrdU), which enabled identification of NPCs that underwent multiple rounds of division. Actively-dividing brain NPCs were found to be apically-localized, whereas actively-dividing NPCs for the ventral nerve cord (VNC) were found apically, basally, and closer to the ventral midline. We used lineage tracing to characterize the changing boundary of the trunk neuroectoderm. Finally, to start to generate a genetic hierarchy, we performed double-fluorescent in-situ hybridization (FISH) and single-FISH plus EdU labeling for neurogenic gene homologs. In the brain and VNC, Ct-soxB1 and Ct-neurogenin were expressed in a large proportion of apically-localized, EdU
NPCs. In contrast, Ct-ash1 was expressed in a small subset of apically-localized, EdU
NPCs and subsurface, EdU
cells, but not in Ct-neuroD
or Ct-elav1
cells, which also were subsurface.
Our data suggest a putative genetic hierarchy with Ct-soxB1 and Ct-neurogenin at the top, followed by Ct-ash1, then Ct-neuroD, and finally Ct-elav1. Comparison of our data with that from Platynereis dumerilii revealed expression of neurogenin homologs in proliferating NPCs in annelids, which appears different than the expression of vertebrate neurogenin homologs in cells that are exiting the cell cycle. Furthermore, differences between neurogenesis in the head versus trunk of C. teleta suggest that these two tissues may be independent developmental modules, possibly with differing evolutionary trajectories.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Multi-walled and single-walled carbon nanotubes were used as nanoadsorbents for the successful removal of Reactive Blue 4 textile dye from aqueous solutions. The adsorbents were characterised by ...infrared and Raman spectroscopy, N(2) adsorption/desorption isotherms and scanning and transmission electron microscopy. The effects of pH, shaking time and temperature on adsorption capacity were studied. In the acidic pH region (pH 2.0), the adsorption of the dye was favourable using both adsorbents. The contact time to obtain equilibrium isotherms at 298-323 K was fixed at 4 hours for both adsorbents. The general order kinetic model provided the best fit to the experimental data compared with pseudo-first order and pseudo-second order kinetic adsorption models. For Reactive Blue 4 dye, the equilibrium data (298 to 323 K) were best fitted to the Liu isotherm model. The maximum sorption capacity for adsorption of the dye occurred at 323 K, attaining values of 502.5 and 567.7 mg g(-1) for MWCNT and SWCNT, respectively. Simulated dyehouse effluents were used to check the applicability of the proposed nanoadsorbents for effluent treatment (removal of 99.89% and 99.98%, for MWCNT and SWCNT, respectively). The interaction of Reactive Blue 4 textile dye with single-walled carbon nanotubes (SWCNTs) was investigated using first principles calculations based on density functional theory. Results from ab initio calculations indicated that Reactive Blue 4 textile dye could be adsorbed on SWCNT through an electrostatic interaction; these results are in agreement with the experimental predictions.
Multi-walled carbon nanotubes (MWCNT) and powder activated carbon (PAC) were used as adsorbents for adsorption of Direct Blue 53 dye (DB-53) from aqueous solutions. The adsorbents were characterised ...using Raman spectroscopy, N2 adsorption/desorption isotherms, and scanning and transmission electron microscopy. The effects of initial pH, contact time and temperature on adsorption capacity of the adsorbents were investigated. At pH 2.0, optimum adsorption of the dye was achieved by both adsorbents. Equilibrium contact times of 3 and 4 h were achieved by MWCNT and PAC adsorbents, respectively. The general order kinetic model provided the best fit of the experimental data compared to pseudo-first order and pseudo-second order kinetic adsorption models. For DB-53 dye, the equilibrium data (298–323 K) were best fitted to the Sips isotherm model. The maximum sorption capacity for adsorption of the dye occurred at 323 K, with the values of 409.4 and 135.2 mg g−1 for MWCNT and PAC, respectively. Studies of adsorption/desorption were conducted and the results showed that DB-53 loaded MWCNT could be regenerated (97.85%) using a mixture 50% acetone + 50% of 3 mol L−1 NaOH. Simulated dye house effluents were used to evaluate the application of the adsorbents for effluent treatment (removal of 99.87% and 97.00% for MWCNT and PAC, respectively, were recorded).
•Adsorption of DB-53 dye was studied using MWCNT and CAC as adsorbents.•MWCNT was characterised using Raman spectroscopy, SEM and TEM techniques.•Maximum adsorption capacities of MWCNT and CAC are 409.4 and 135.2 mg/g, respectively.•The adsorption processes are well described by general order kinetic model.•MWCNT and CAC have been proven effective for removal of DB-53 dye.
Calciprotein particle maturation time (T50) in serum is a novel measure of individual blood calcification propensity. To determine the clinical relevance of T50 in renal transplantation, baseline ...serum T50 was measured in a longitudinal cohort of 699 stable renal transplant recipients and the associations of T50 with mortality and graft failure were analyzed over a median follow-up of 3.1 years. Predictive value of T50 was assessed for patient survival with reference to traditional (Framingham) risk factors and the calcium-phosphate product. Serum magnesium, bicarbonate, albumin, and phosphate levels were the main determinants of T50, which was independent of renal function and dialysis vintage before transplant. During follow-up, 81 (12%) patients died, of which 38 (47%) died from cardiovascular causes. Furthermore, 45 (6%) patients developed graft failure. In fully adjusted models, lower T50 values were independently associated with increased all-cause mortality (hazard ratio, 1.43; 95% confidence interval, 1.11 to 1.85; P=0.006 per SD decrease) and increased cardiovascular mortality (hazard ratio, 1.55; 95% confidence interval, 1.04 to 2.29; P=0.03 per SD decrease). In addition to age, sex, and eGFR, T50 improved prognostication for all-cause mortality, whereas traditional risk factors or calcium-phosphate product did not. Lower T50 was also associated with increased graft failure risk. The associations of T50 with mortality and graft failure were confirmed in an independent replication cohort. In conclusion, reduced serum T50 was associated with increased risk of all-cause mortality, cardiovascular mortality, and graft failure and, of all tested parameters, displayed the strongest association with all-cause mortality in these transplant recipients.
ABSTRACT
Understanding the variation in training and nuances of trauma provider practice between the countries in Europe and the United States is a daunting task. This article briefly reviews the key ...specialties of trauma care in Europe including emergency medical services (EMS), emergency medicine, anesthesia, trauma surgery, and critical care. The authors hope to inform U.S. military clinicians and medical planners of the major differences in emergency and trauma care that exist across Europe. Emergency medicine exists as both a primary specialty and a subspecialty across Europe, with varying stages of development as a specialty in each country. There is heavy physician involvement in EMS in much of Europe, with anesthesiologists having additional EMS training typically providing prehospital critical care. Because of the historical predominance of blunt trauma in Europe, in many countries, trauma surgery is a subspecialty with initial orthopedic surgery training versus general surgery. Intensive care medicine has various training pathways across Europe, but there have been great advances in standardizing competency requirements across the European Union. Finally, the authors suggest some strategies to mitigate the potential negative consequences of joint medical teams and how to leverage some key differences to advance life-saving medical interoperability across the North Atlantic Treaty Organization alliance.
•The puberty constitutes a vulnerable period during which Peak Bone Mass can be affected.•Diagnosis and management of osteoporosis in the young can be challenging.•Secondary causes of excessive bone ...loss need to be excluded.•Young adults with low bone mineral density do not necessarily need to be treated.
This narrative review discusses several aspects of the management of osteoporosis in patients under 50 years of age. Peak bone mass is genetically determined but can also be affected by lifestyle factors. Puberty constitutes a vulnerable period. Idiopathic osteoporosis is a rare, heterogeneous condition in young adults due in part to decreased osteoblast function and deficient bone acquisition. There are no evidence-based treatment recommendations. Drugs use can be proposed to elderly patients at very high risk. Diagnosis and management of osteoporosis in the young can be challenging, in particular in the absence of a manifest secondary cause. Young adults with low bone mineral density (BMD) do not necessarily have osteoporosis and it is important to avoid unnecessary treatment. A determination of BMD is recommended for premenopausal women who have had a fragility fracture or who have secondary causes of osteoporosis: secondary causes of excessive bone loss need to be excluded and treatment should be targeted. Adequate calcium, vitamin D, and a healthy lifestyle should be recommended. In the absence of fractures, conservative management is generally sufficient, but in rare cases, such as chemotherapy-induced osteoporosis, antiresorptive medication can be used. Osteoporosis in young men is most often of secondary origin and hypogonadism is a major cause; testosterone replacement therapy will improve BMD in these patients. Diabetes is characterized by major alterations in bone quality, implying that medical therapy should be started sooner than for other causes of osteoporosis. Primary hyperparathyroidism, hyperthyroidism, Cushing’s syndrome and growth hormone deficiency or excess affect cortical bone more often than trabecular bone.
Knowledge on the spatial distribution, habitat use and processes of site selection by marine turtles is fundamental to identify key habitats, critical resources, and discrete foraging aggregations ...for protection. This is particularly important for regions of known importance for marine turtles and where widespread habitat degradation is taking place. The waters surrounding Bimini, Bahamas, provide important foraging areas for threatened juvenile green turtles (
Chelonia mydas
) however, these habitats are being severely degraded by coastal development. To inform managers on the design of planned future no-take marine protected areas (MPA) in Bimini, we used a spatial planning approach and incorporated diverse methodologies (e.g., visual surveys, capture events, passive acoustic telemetry) to identify areas of high use by juvenile green turtles. We also assessed forage items to understand habitat use by green turtles. This information was compared with how various stakeholders use the local waters to identify priority areas for protection within Bimini to maximize conservation of green turtles, while minimizing impact to society, and to meet the conservation target previously stipulated by government officials. Two regions within Bimini (South Flats in south Bimini and Bonefish Hole on the north Island) were identified as important areas for protection and suggestions are made on their considerations for MPA implementation.
Abstract
Predator–prey interactions are ubiquitous and under strong selection because of the consequences experienced by both predator and prey if they lose the interaction. Biomechanics and behavior ...play important roles in the outcome of these interactions, but many studies focus on the prey, restrict the range of behaviors considered, and the role of prey boldness in the outcome is not understood. We used high‐speed video to test for effects of multiple measures of performance and kinematics of both the predator and prey, and boldness of prey on the outcome of interactions between Pike Cichlids (
Crenicichla
sp.) and Guppies (
Poecilia reticulata
). We found high variation in the behaviors employed during the predator–prey interactions, including in suction versus raptorial feeding, strike accuracy, and guppy responsiveness. We also found that predators moving relatively slower and prey moving relatively faster were more successful at consuming the prey and evading the predator, respectively. Prey that reacted farther from the predator was more likely to escape predation, but boldness of the prey did not affect the interaction. Our work suggests that a high level of variation in predator–prey interactions is widespread, even when strike and escape behaviors are stereotyped. We also showed that what both the predator and the prey do during an interaction are important in determining the outcome.
PDF
