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1.
Proc Biol Sci ; 291(2019): 20232519, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38503331

RESUMO

Despite decades of research, surprisingly little is known about the mechanism(s) by which an individual's genotype is encoded in odour. Many studies have focused on the role of the major histocompatibility complex (MHC) owing to its importance for survival and mate choice. However, the salience of MHC-mediated odours compared to chemicals influenced by the rest of the genome remains unclear, especially in wild populations where it is challenging to quantify and control for the effects of the genomic background. We addressed this issue in Antarctic fur seals by analysing skin swabs together with full-length MHC DQB II exon 2 sequences and data from 41 genome-wide distributed microsatellites. We did not find any effects of MHC relatedness on chemical similarity and there was also no relationship between MHC heterozygosity and chemical diversity. However, multilocus heterozygosity showed a significant positive association with chemical diversity, even after controlling for MHC heterozygosity. Our results appear to rule out a dominant role of the MHC in the chemical encoding of genetic information in a wild vertebrate population and highlight the need for genome-wide approaches to elucidate the mechanism(s) and specific genes underlying genotype-odour associations.


Assuntos
Otárias , Animais , Otárias/genética , Genótipo , Heterozigoto , Complexo Principal de Histocompatibilidade/genética , Odorantes , Regiões Antárticas
2.
Am J Physiol Regul Integr Comp Physiol ; 327(1): R46-R53, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38766773

RESUMO

Despite elite human free divers achieving incredible feats in competitive free diving, there has yet to be a study that compares consummate divers, (i.e. northern elephant seals) to highly conditioned free divers (i.e., elite competitive free-diving humans). Herein, we compare these two diving models and suggest that hematological traits detected in seals reflect species-specific specializations, while hematological traits shared between the two species are fundamental mammalian characteristics. Arterial blood samples were analyzed in elite human free divers (n = 14) during a single, maximal volitional apnea and in juvenile northern elephant seals (n = 3) during rest-associated apnea. Humans and elephant seals had comparable apnea durations (∼6.5 min) and end-apneic arterial Po2 [humans: 40.4 ± 3.0 mmHg (means ± SE); seals: 27.1 ± 5.9 mmHg; P = 0.2]. Despite similar increases in arterial Pco2 (humans: 33 ± 5%; seals: 16.3 ± 5%; P = 0.2), only humans experienced reductions in pH from baseline (humans: 7.45 ± 0.01; seals: 7.39 ± 0.02) to end apnea (humans: 7.37 ± 0.01; seals: 7.38 ± 0.02; P < 0.0001). Hemoglobin P50 was greater in humans compared to elephant seals (29.9 ± 1.5 and 28.7 ± 0.6 mmHg, respectively; P = 0.046). Elephant seals overall had higher carboxyhemoglobin (COHb) levels (5.9 ± 2.6%) compared to humans (0.8 ± 1.2%; P < 0.0001); however, following apnea, COHb was reduced in seals (baseline: 6.1 ± 0.3%; end apnea: 5.6 ± 0.3%) and was slightly elevated in humans (baseline: 0.7 ± 0.1%; end apnea: 0.9 ± 0.1%; P < 0.0002, both comparisons). Our data indicate that during static apnea, seals have reduced hemoglobin P50, greater pH buffering, and increased COHb levels. The differences in hemoglobin P50 are likely due to the differences in the physiological environment between the two species during apnea, whereas enhanced pH buffering and higher COHb may represent traits selected for in elephant seals.NEW & NOTEWORTHY This study uses similar methods and protocols in elite human free divers and northern elephant seals. Using highly conditioned divers (elite free-diving humans) and highly adapted divers (northern elephant seals), we explored which hematological traits are fundamentally mammalian and which may have been selected for. We found differences in P50, which may be due to different physiological environments between species, while elevated pH buffering and carbon monoxide levels might have been selected for in seals.


Assuntos
Apneia , Mergulho , Focas Verdadeiras , Animais , Focas Verdadeiras/sangue , Humanos , Mergulho/fisiologia , Apneia/sangue , Apneia/fisiopatologia , Masculino , Adulto , Feminino , Especificidade da Espécie , Hemoglobinas/metabolismo , Adulto Jovem , Dióxido de Carbono/sangue , Oxigênio/sangue
3.
Mol Ecol ; 33(7): e17293, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38419064

RESUMO

The harbour seal Phoca vitulina is a ubiquitous pinniped species found throughout coastal waters of the Northern Hemisphere. Harbour seal impacts on ecosystem dynamics may be significant due to their high abundance and food web position. Two subspecies exist in North America, P. v. richardii in the Pacific Ocean and P. v. vitulina in the Atlantic. Strong natal philopatry of harbour seals can result in fine-scale genetic structure and isolation by distance. Management of harbour seals is expected to benefit from improved resolution of seal population structure and dynamics. Here, we use genotyping-by-sequencing to genotype 146 harbour seals from the eastern Pacific Ocean (i.e. British Columbia (BC), Oregon and California) and the western Atlantic Ocean (i.e. Québec, Newfoundland and Labrador). Using 12,742 identified variants, we confirm the recently identified elevated genetic diversity in the eastern Pacific relative to the western Atlantic and greatest differentiation between the subspecies. Further, we demonstrate that this is independent of reference genome bias or other potential technical artefacts. Coast-specific analyses with 8933 and 3828 variants in Pacific and Atlantic subspecies, respectively, identify divergence between BC and Oregon-California, and between Québec and Newfoundland-Labrador. Unexpected PCA outlier clusters were observed in two populations due to cryptic relatedness of individuals; subsequently, closely related samples were removed. Admixture analysis indicates an isolation-by-distance signature where Oregon seals contained some of the BC signature, whereas California did not. Additional sampling is needed in the central and north coast of BC to determine whether a discrete separation of populations exists within the region.


Assuntos
Phoca , Humanos , Animais , Phoca/genética , Colúmbia Britânica , Ecossistema , Metagenômica , California
4.
Glob Chang Biol ; 30(3): e17186, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38450925

RESUMO

The Arctic is a global warming 'hot-spot' that is experiencing rapid increases in air and ocean temperatures and concomitant decreases in sea ice cover. These environmental changes are having major consequences on Arctic ecosystems. All Arctic endemic marine mammals are highly dependent on ice-associated ecosystems for at least part of their life cycle and thus are sensitive to the changes occurring in their habitats. Understanding the biological consequences of changes in these environments is essential for ecosystem management and conservation. However, our ability to study climate change impacts on Arctic marine mammals is generally limited by the lack of sufficiently long data time series. In this study, we took advantage of a unique dataset on hooded seal (Cystophora cristata) movements (and serum samples) that spans more than 30 years in the Northwest Atlantic to (i) investigate foraging (distribution and habitat use) and dietary (trophic level of prey and location) habits over the last three decades and (ii) predict future locations of suitable habitat given a projected global warming scenario. We found that, despite a change in isotopic signatures that might suggest prey changes over the 30-year period, hooded seals from the Northwest Atlantic appeared to target similar oceanographic characteristics throughout the study period. However, over decades, they have moved northward to find food. Somewhat surprisingly, foraging habits differed between seals breeding in the Gulf of St Lawrence vs those breeding at the "Front" (off Newfoundland). Seals from the Gulf favoured colder waters while Front seals favoured warmer waters. We predict that foraging habitats for hooded seals will continue to shift northwards and that Front seals are likely to have the greatest resilience. This study shows how hooded seals are responding to rapid environmental change and provides an indication of future trends for the species-information essential for effective ecosystem management and conservation.


Assuntos
Caniformia , Focas Verdadeiras , Animais , Ecossistema , Aquecimento Global , Hábitos
5.
Glob Chang Biol ; 30(3): e17191, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38433338

RESUMO

The response to climate change in highly dimorphic species can be hindered by differences between sexes in habitat preferences and movement patterns. The Antarctic fur seal, Arctocephalus gazella, is the most abundant pinniped in the Southern Hemisphere, and one of the main consumers of Antarctic krill, Euphausia superba, in the Southern Ocean. However, the populations breeding in the Atlantic Southern Ocean are decreasing, partly due to global warming. Male and female Antarctic fur seals differ greatly in body size and foraging ecology, and little is known about their sex-specific responses to climate change. We used satellite tracking data and Earth System Models to predict changes in habitat suitability for male and female Antarctic fur seals from the Western Antarctic Peninsula under different climate change scenarios. Under the most extreme scenario (SSP5-8.5; global average temperature +4.4°C projected by 2100), suitable habitat patches will shift southward during the non-breeding season, leading to a minor overall habitat loss. The impact will be more pronounced for females than for males. The reduction of winter foraging grounds might decrease the survival of post-weaned females, reducing recruitment and jeopardizing population viability. During the breeding season, when males fast on land, suitable foraging grounds for females off the South Shetland Islands will remain largely unmodified, and new ones will emerge in the Bellingshausen Sea. As Antarctic fur seals are income breeders, the foraging grounds of females should be reasonably close to the breeding colony. As a result, the new suitable foraging grounds will be useful for females only if nearby beaches currently covered by sea ice emerge by the end of the century. Furthermore, the colonization of these new, ice-free breeding locations might be limited by strong female philopatry. These results should be considered when managing the fisheries of Antarctic krill in the Southern Ocean.


La resposta al canvi climàtic en espècies amb dimorfisme sexual pot veure's dificultada per les diferències entre sexes respecte a les seves preferències d'ús de l'hàbitat i els seus patrons de moviment. L'os marí antàrtic (Arctocephalus gazella), és el pinnípede més abundant a l'Hemisferi Sud i un dels principals consumidors de krill antàrtic, (Euphausia superba), a l'Oceà Antàrtic. No obstant això, les poblacions que es reprodueixen al sector Atlàntic de l'Oceà Antàrtic estan disminuint, en part a causa de l'escalfament global. Els mascles i les femelles de l'os marí antàrtic difereixen considerablement en la seva mida corporal i ecologia tròfica, i es té poc coneixement sobre les seves respostes específiques al canvi climàtic. En aquest estudi hem utilitzat dades de seguiment per satèl·lit i models del Sistema Terrestre per predir els canvis en la idoneïtat de l'hàbitat per als mascles i les femelles d'os marí antàrtic de la Península Antàrtica Occidental sota diferents escenaris de canvi climàtic. Sota l'escenari més extrem (SSP5-8.5; temperatura mitjana mundial +4.4°C prevista per a 2100), les zones d'hàbitat idoni es desplaçaran cap al sud durant l'època d'hivernada (no reproducció), provocant una lleugera pèrdua d'hàbitat idoni. Tot i això, l'impacte serà més pronunciat per a les femelles que per als mascles. Aquesta reducció dels territoris d'alimentació durant l'hivern podria disminuir la supervivència de les femelles postdeslletades, reduint-ne el reclutament i posant en perill la viabilitat de la població. Durant l'època de cria, quan els mascles es troben majoritàriament en dejú a terra, els territoris d'alimentació idonis per a les femelles al voltant de les Illes Shetland del Sud romandran en gran part sense modificar-se, i n'emergiran de nous al mar de Bellingshausen. Com que les femelles d'os marí antàrtic es continuen alimentant durant la cria, els territoris d'alimentació de les femelles han d'estar raonablement a prop de la colònia de cria. Com a resultat, aquestes noves zones d'alimentació seran útils només si les platges properes, actualment cobertes de gel marí, emergeixen al llarg del segle. A més, la colonització d'aquests nous llocs de reproducció lliures de gel podria veure's limitada per la forta filopatria de les femelles. Aquests resultats haurien de tenir-se en compte en la gestió de les pesqueries de krill a l'Oceà Antàrtic.


Assuntos
Otárias , Feminino , Masculino , Animais , Regiões Antárticas , Oceano Atlântico , Tamanho Corporal , Mudança Climática
6.
J Exp Biol ; 227(7)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38495024

RESUMO

Regulation of mitochondrial oxidative phosphorylation is essential to match energy supply to changing cellular energy demands, and to cope with periods of hypoxia. Recent work implicates the circadian molecular clock in control of mitochondrial function and hypoxia sensing. Because diving mammals experience intermittent episodes of severe hypoxia, with diel patterning in dive depth and duration, it is interesting to consider circadian-mitochondrial interaction in this group. Here, we demonstrate that the hooded seal (Cystophora cristata), a deep-diving Arctic pinniped, shows strong daily patterning of diving behaviour in the wild. Cultures of hooded seal skin fibroblasts exhibit robust circadian oscillation of the core clock genes per2 and arntl. In liver tissue collected from captive hooded seals, expression of arntl was some 4-fold higher in the middle of the night than in the middle of the day. To explore the clock-mitochondria relationship, we measured the mitochondrial oxygen consumption in synchronized hooded seal skin fibroblasts and found a circadian variation in mitochondrial activity, with higher coupling efficiency of complex I coinciding with the trough of arntl expression. These results open the way for further studies of circadian-hypoxia interactions in pinnipeds during diving.


Assuntos
Caniformia , Focas Verdadeiras , Animais , Encéfalo/metabolismo , Fatores de Transcrição ARNTL/metabolismo , Mamíferos/metabolismo , Hipóxia/metabolismo , Focas Verdadeiras/fisiologia , Mitocôndrias/metabolismo
7.
J Theor Biol ; 595: 111933, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39260737

RESUMO

We report the effects of varying physiological and other properties on the heat and water exchange in the maxilloturbinate structure (MT) of the bearded seal (Erignathus barbatus or Eb) in realistic environments, using a computational fluid dynamics (CFD) model. We find that the water retention in percent is very high (about 90 %) and relatively unaffected by either cold (-30 °C) or warm (10 °C) conditions. The retention of heat is also high, around 80 % . Based on a consideration of entropy production by the maxilloturbinate system, we show that anatomical and physiological properties of the seal provide good conditions for heat and water exchange at the mucus lining in the seal's nasal cavity. At normal values of tidal volume and maxilloturbinate (MT) length, the air temperature in the MT reaches the body temperature before the air has left the MT channels. This confers a safety factor which is expected to be helpful in exercise, when ventilation increases.

8.
J Endovasc Ther ; : 15266028241266182, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39082670

RESUMO

PURPOSE: This single-center study aimed to assess patients who underwent intentional percutaneous endovascular aortic aneurysm repair (pEVAR) with Hybrid Technique combining a single Perclose (Abbott, Abbott Park, Illinois) Suture-Mediated Closure Device + single Angio-Seal VIP 8F (Terumo, Tokyo, Japan) and compare outcomes with the standard Dual Perclose technique. Materials and Methods: Consecutive elective pEVAR patients treated from November 2022 to November 2023, with healthy femoral accesses and introducer sheaths ≤20 French (F) outer diameter, were included. Coin-toss randomization determined whether a combination of single Perclose Device + single Angio-Seal VIP 8F (Hybrid Technique) or the standard double Perclose Devices (Dual Perclose) was used. In Hybrid Technique, a single Perclose device was positioned at 12 o'clock; a single Angio-Seal VIP 8F was placed after sheaths removal. Dual Perclose followed standard procedure. Primary endpoints included immediate hemostasis, sheath diameter differences, access conversion rate, technical success, and cost analysis. RESULTS: The study involved 60 pEVAR patients (median age=78, interquartile range [IQR]=72-85 years) within the inclusion criteria. In 14 (24%) cases, only 1 femoral access was studied. There were 106 pEVAR accesses, with 58 (54.7%) in the Hybrid Technique group and 48 (45.3%) in the Dual Perclose group. Both groups exhibited homogeneity in pre-operative characteristics and sheath diameter (Hybrid Technique-16F vs Dual Perclose-18F; p=0.202). Immediate hemostasis was achieved in 100% of the Hybrid Technique group vs 87.5% for the Dual Perclose group (p=0.006). Surgical access conversion was unnecessary. Technical success was 100%, with all 6 femoral bleeding cases after Dual Perclose resolved endovascularly, using additional devices. Cost analysis showed a median cost of 330 euros (IQR=0) for the Hybrid Technique group vs 384 euros (IQR=360-456) for the Dual Perclose group (p<0.001). Thirty-day mortality was 3%, in 2 fragile patients, without access-related complications. Multivariate analysis identified Dual Perclose access (odds ratio [OR]=35.6; 95% confidence interval [CI]=18.3-36.8; p<0.001) and obesity (OR=19.7; 95% CI=1.4-23.9.5; p<0.001) as independent risk factors for immediate hemostasis failure. Median follow-up was 134 days (IQR=41-227), with 1 Hybrid Technique case (2%) successfully treated with thrombin injection for a small femoral pseudoaneurysm after 62 days. CONCLUSIONS: The elective Hybrid Technique with combination of single Perclose Device + single Angio-Seal VIP 8F during pEVAR in selected patients appears to be non-inferior to the standard Dual Perclose procedure. It demonstrates a positive trend in reducing immediate hemostasis failure and costs. Both procedures achieved technical success and avoiding surgical access conversions. CLINICAL IMPACT: This study introduces a novel elective hybrid technique combining a single Perclose device with a single Angio-Seal VIP 8Fr for percutaneous endovascular abdominal aortic interventions. Results for hybrid technique showed 100% technical success and efficient immediate hemostasis, while costing less than standard dual Perclose procedure. Both procedures did not require surgical conversions. Despite being a single-center study, it demonstrates potential benefits of the intentional application of this hybrid technique towards minimally invasiveness. Obesity and dual Perclose technique were identified as independent risk factors for hemostasis failure, reaffirming the hybrid technique procedure's efficacy as well as and non-inferiority to standard procedure.

9.
Environ Sci Technol ; 58(33): 14797-14811, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39120259

RESUMO

Short-, medium-, and long-chain chlorinated paraffins (CPs) (SCCPs, MCCPs, and LCCPs) and dechloranes are chemicals of emerging concern; however, little is known of their bioaccumulative potential compared to legacy contaminants in marine mammals. Here, we analyzed SCCPs, MCCPs, LCCPs, 7 dechloranes, 4 emerging brominated flame retardants, and 64 legacy contaminants, including polychlorinated biphenyls (PCBs), in the blubber of 46 individual marine mammals, representing 10 species, from Norway. Dietary niche was modeled based on stable isotopes of nitrogen and carbon in the skin/muscle to assess the contaminant accumulation in relation to diet. SCCPs and dechlorane-602 were strongly positively correlated with legacy contaminants and highest in killer (Orcinus orca) and sperm (Physeter macrocephalus) whales (median SCCPs: 160 ng/g lw; 230 ng/g lw and median dechlorane-602: 3.8 ng/g lw; 2.0 ng/g lw, respectively). In contrast, MCCPs and LCCPs were only weakly correlated to recalcitrant legacy contaminants and were highest in common minke whales (Balaenoptera acutorostrata; median MCCPs: 480 ng/g lw and LCCPs: 240 ng/g lw). The total contaminant load in all species was dominated by PCBs and legacy chlorinated pesticides (63-98%), and MCCPs dominated the total CP load (42-68%, except 11% in the long-finned pilot whale Globicephala melas). Surprisingly, we found no relation between contaminant concentrations and dietary niche, suggesting that other large species differences may be masking effects of diet such as lifespan or biotransformation and elimination capacities. CP and dechlorane concentrations were higher than in other marine mammals from the (sub)Arctic, and they were present in a killer whale neonate, indicating bioaccumulative properties and a potential for maternal transfer in these predominantly unregulated chemicals.


Assuntos
Poluentes Orgânicos Persistentes , Animais , Noruega , Poluentes Orgânicos Persistentes/metabolismo , Hidrocarbonetos Clorados/metabolismo , Parafina/metabolismo , Mamíferos/metabolismo , Monitoramento Ambiental , Retardadores de Chama/metabolismo , Dieta , Bifenilos Policlorados/metabolismo
10.
Artigo em Inglês | MEDLINE | ID: mdl-39105326

RESUMO

OBJECTIVES: Examine the histomorphometric bone composition, following alveolar ridge preservation techniques and unassisted socket healing. MATERIALS AND METHODS: Forty-two patients (42) requiring a single rooted tooth extraction were randomly allocated into three groups (n = 14 per group): Group 1: Guided Bone Regeneration (GBR) using deproteinised bovine bone mineral (DBBM) and a porcine collagen membrane; Group 2: Socket Seal (SS) technique using DBBM and a porcine collagen matrix; Group 3: Unassisted socket healing (Control). Trephined bone biopsies were harvested following a 4-month healing period. Forty-two samples underwent Back-Scattered Electrons -Scanning Electron Microscopy (BSE-SEM) imaging, with 15 samples examined using Xray Micro-Tomography (XMT) (n = 6 for each GBR/SS and n = 3 Control). Images were analysed to determine the percentage (%) of connective tissue, new bone formation, residual DBBM particles and direct bone to DBBM particle contact (osseointegration). RESULTS: BSE-SEM analysis demonstrated that new bone formation was higher in the Control (45.89% ± 11.48) compared to both GBR (22.12% ± 12.7/p < .004) and SS (27.62% ± 17.76/p < .005) groups. The connective tissue percentage in GBR (49.72% ± 9), SS (47.81% ± 12.57) and Control (47.81% ± 12.57) groups was similar. GBR (28.17% ± 16.64) and SS (24.37% ± 18.61) groups had similar levels of residual DBBM particles. XMT volumetric analysis indicated a lower level of bone and DBBM particles in all test groups, when matched to the BSE-SEM area measurements. Osseointegration levels (DBBM graft and bone) were recorded at 35.66% (± 9.8) for GBR and 31.18% (± 19.38) for SS. CONCLUSION: GBR and SS ARP techniques presented with less bone formation when compared to unassisted healing. GBR had more direct contact/osseointegration between the DBBM particles and newly formed bone.

11.
Anaesthesia ; 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39110995

RESUMO

BACKGROUND: The i-gel® Plus is a modified version of the i-gel® supraglottic airway device. It contains a wider drainage port; a longer tip; ramps inside the breathing channel; and an additional port for oxygen delivery. There has been no prospective evaluation of this device in clinical practice. METHODS: This international, multicentre, prospective cohort study aimed to evaluate the performance of the i-gel Plus in adult patients undergoing elective procedures under general anaesthesia. The primary outcome was overall insertion success rate, defined as the ability to provide effective airway management through the device from insertion until the end of the surgical procedure. Secondary outcomes included device performance and incidence of postoperative adverse events. Data from the first 1000 patients are reported. RESULTS: In total, 1012 patients were enrolled; 12 forms were excluded from the final analysis due to incomplete data leaving 1000 included patients (545 female). Overall insertion success rate was 98.6%, with a first-attempt success rate of insertion of 88.2%. A significant difference between females and males was seen for the overall success rate (97.4% vs. 99.6% respectively) but not for first-attempt successful insertion. Mean (SD) oropharyngeal seal pressure was 32 (7) cmH2O. The only independent factor that increased the risk of first-attempt failure was low operator experience. Complications included desaturation < 85% in 0.6%; traces of blood on the device in 7.4%; laryngospasm in 0.5%; and gastric contents inside the bowl in 0.2% of patients. CONCLUSIONS: The i-gel Plus appears to be an effective supraglottic airway device that is associated with a high insertion success rate and a reasonably low incidence of complications.

12.
Anim Welf ; 33: e5, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38487790

RESUMO

The present study aimed to investigate the relationship between shooting angle to the head and animal welfare outcomes in the hunt of young harp seals (Pagophilus groenlandicus). The study population consisted of young harp seals belonging to the Greenland Sea harp seal population. A sample of 171, 2-7 weeks old, weaned harp seals of both sexes were included. The study was conducted as an open, randomised parallel group designed trial during the regular hunt. The animals were allocated into four groups, A-D, according to the observed shooting angle to the head, defined as the angle between the direction of the shot and the longitudinal axis of the animal's head: (A) directly from the front; (B) obliquely from the front; (C) directly from the side; and (D) obliquely or directly from behind. Instantaneous death rate (IDR) and time to death (TTD) were the main variables. The mean IDR differed significantly between groups and was highest in group B (96.8%) and lowest in group C (66.7%). For all groups combined it was 84.2%. The mean TTD for seals not rendered instantaneously unconscious or dead (n = 27) differed significantly between groups and was shortest in group A (16 s) and longest in group C (85 s). However, the number of animals included in the TTD analysis was limited. In conclusion, based on the significantly higher IDR, the shooting angle obliquely from the front is recommended to help achieve the best animal welfare outcomes during the hunt of young harp seals.

13.
Pediatr Exerc Sci ; : 1-13, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39293790

RESUMO

The Danish Christmas Seal Homes offer a 10-week residential stay for socially vulnerable children. We aimed to examine the effects on body composition and cardiometabolic fitness variables of the standard program (SG) and whether substituting physical activity sessions with sessions from a football-based health education program is beneficial for the participants ("11 for Health"; SG+). Three hundred and nine children participated in SG (12.4 [1.6] y) and 305 in SG+ (12.4 [1.4] y). Fat percentage was lowered by 6% for females (from 37% to 31%) and 8% for males (from 36% to 28%), with no between-group differences. We observed improvements in systolic and diastolic blood pressure (3 and 5 mm Hg, respectively), resting heart rate (10 beats/min), aerobic fitness, jump performance, and relative muscle mass with no between-group differences. Furthermore, there were between-group differences in insulin levels for females (1.7 pmol/L; 95% CI, 0.3 to 3.0) and postural balance for males (1.0 s; 95% CI, 0.0 to 2.0), both in favor of SG+, and covered distance in the Andersen test for females (26 m; 95% CI, 3 to 49) in favor of SG. In conclusion, a 10-week stay at the Danish Christmas Seal Home resulted in clinically relevant improvement in fat percentage and cardiometabolic fitness in socially vulnerable children, regardless of the program type.

14.
Clin Oral Investig ; 28(9): 484, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39138740

RESUMO

OBJECTIVES: To assess and compare the clinical, radiological, and histological outcomes of socket seal surgery between two protocols: deproteinized demineralized tooth matrix (dpDTM) and freeze-dried bone allograft (FDBA) each covered with a free gingival graft. MATERIALS AND METHODS: Twenty extraction sockets in the anterior or premolar region were randomly allocated to either the dpDTM or FDBA protocol (n = 10 per group). Measurements of the alveolar ridge changes were obtained using an intraoral scanner and cone-beam computed tomography at 3 months post-operation. Three-month post surgery, the dental implant was installed (n = 5 per group), bone biopsies were obtained for histomorphometrical and micro-computed tomography analyses. Implant stability quotients (ISQs) were determined and compared at 3 months post-implant. RESULTS: Lower significant reductions in buccal alveolar ridge height and hard tissue volume were observed in dpDTM group compared to FDBA group at 3 months (0.25 ± 0.35 mm vs. 1.60 ± 0.66 mm [p = .000] and 9.64 ± 15.39% mm3 vs. 31.45 ± 18.11% mm3 [p = .010], respectively). At the same time, lower soft tissue volume reduction was detected in the dpDTM group compared to FDBA group (4.21 ± 5.25% mm3 vs. 5.25 ± 5.79% mm3). No statistically significant difference in the percentage of mineralized tissue formation was found between dpDTM group (53.39 ± 11.16%) and FDBA group (49.90 ± 3.27%). Even though the ISQ in the dpDTM group showed a higher value than the FDBA group at 3 months post-implant, the results were without statistical significance. CONCLUSIONS: Alveolar ridge preservation using dpDTM is an efficacious procedure for providing the conditions for the development of functional and esthetic implants.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Alvéolo Dental , Humanos , Alvéolo Dental/cirurgia , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Resultado do Tratamento , Transplante Ósseo/métodos , Microtomografia por Raio-X , Implantação Dentária Endóssea/métodos , Aumento do Rebordo Alveolar/métodos , Extração Dentária , Biópsia , Gengiva , Perda do Osso Alveolar/prevenção & controle , Perda do Osso Alveolar/diagnóstico por imagem , Processo Alveolar/diagnóstico por imagem , Processo Alveolar/patologia , Processo Alveolar/cirurgia , Dentina
15.
Sensors (Basel) ; 24(16)2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39205112

RESUMO

Seals, sea lions, and other aquatic animals rely on their whiskers to identify and track underwater targets, offering valuable inspiration for the development of low-power, portable, and environmentally friendly sensors. Here, we design a single seal-whisker-like cylinder and conduct experiments to measure the forces acting on it with nine different upstream targets. Using sample sets constructed from these force signals, a convolutional neural network (CNN) is trained and tested. The results demonstrate that combining the seal-whisker-style sensor with a CNN enables the identification of objects in the water in most cases, although there may be some confusion for certain targets. Increasing the length of the signal samples can enhance the results but may not eliminate these confusions. Our study reveals that high frequencies (greater than 5 Hz) are irrelevant in our model. Lift signals present more distinct and distinguishable features than drag signals, serving as the primary basis for the model to differentiate between various targets. Fourier analysis indicates that the model's efficacy in recognizing different targets relies heavily on the discrepancies in the spectral features of the lift signals.


Assuntos
Redes Neurais de Computação , Animais , Vibrissas/fisiologia , Focas Verdadeiras/fisiologia
16.
J Vet Pharmacol Ther ; 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39003597

RESUMO

Pharmacokinetics studies have investigated meloxicam, a non-steroidal anti-inflammatory drug, dosing strategies in a wide variety of non-domestic animals; however, there is no prior study examining well-founded dosing for pinnipeds. To develop dosing protocols, pharmacokinetic information is needed, with an examination of differences between pinniped species. Apparently, healthy California sea lions (Zalophus californianus: CSL; n = 13) and Pacific harbor seals (Phoca vitulina richardii: PHS; n = 17) that had completed rehabilitation were enrolled into a population-based pharmacokinetic study. Each animal was administered a single oral dose of meloxicam at 0.1 mg/kg, and two blood samples were collected from each animal at varying intervals during a 96-h study period. Plasma concentrations of meloxicam were determined by high-pressure liquid chromatography. Data were analyzed with nonlinear mixed effects modeling (Phoenix® NLME™, Certara, St. Louis, MO 63105, USA). The results indicated that in PHS, peak plasma concentration (Cmax) was 0.33 µg/mL with an elimination half-life (Ke t½) of 31.53 h. In CSL, Cmax was 0.17 µg/mL with Ke t½ of 32.71 h. All animals enrolled completed the study without outward adverse clinical signs. The elimination half-life was longer than previously recommended dosing intervals for pinnipeds; however, we cannot speculate in the optimum clinical dose from these results.

17.
Environ Manage ; 73(3): 614-633, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37910218

RESUMO

Sea-level rise is particularly concerning for tidal wetlands that reside within an area with steep topography or are constrained by human development and alteration of sedimentation. Sediment augmentation to increase wetland elevations has been considered as a potential strategy for such areas to prevent wetland loss over the coming decades. However, there is little information on the best approaches and whether adaptive management actions can mimic natural processes to build sea-level rise resilience. In addition, the lack of information on long-term marsh characteristics, processes, and variability can hamper development of effective augmentation strategies. Here, we assess a case study in a southern California marsh to determine the nature of the pre-existing sediments and variability of the site in relation to sediments applied during an augmentation experiment. Although sediment cores revealed natural variations in the grain size and organic content of sediments deposited at the site over the past 1500 years, the applied sediments were markedly coarser in grain size than prehistoric sediments at the site (100% maximum sand versus 76% maximum sand). The rate of the experimental sediment application (25.1 ± 1.09 cm in ~2 months) was also much more rapid than natural accretion rates measured for the site historically. In contrast, post-augmentation sediment accretion rates on the augmentation site have been markedly slower than pre-augmentation rates or current rates on a nearby control site. The mismatch between the characteristics of the applied sediment and thickness of application and the historic conditions are likely strong contributors to the slow initial recovery of vegetation. Sediment augmentation has been shown to be a useful strategy in some marshes, but this case study illustrates that vegetation recovery may be slow if applied sediments are not similar or at a thickness similar to historic conditions. However, testing adaptation strategies to build wetland elevations is important given the long-term risk of habitat loss with sea-level rise. Lessons learned in the case study could be applied elsewhere.


Assuntos
Sedimentos Geológicos , Áreas Alagadas , Humanos , Areia , Ecossistema
18.
Mil Psychol ; 36(3): 286-300, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38661469

RESUMO

Mindfulness and resilience are thought to be essential qualities of the military's special operations community. Both are tested daily in Special Operations Forces (SOF) assessment and selection efforts to prepare candidates to persist through grueling training and complex combat situations; but these qualities are rarely measured. While military leadership places value on the concepts of mindfulness and resilience, there is minimal empirical research examining the role that they play in the completion of training. This longitudinal study followed three classes of SEAL candidates at Basic Underwater Demolition/SEAL (BUD/S) training over their six-month selection program. We estimated logit models predicting successful completion of BUD/S and specific types of failure in that training environment with indexes of mindfulness and resilience at the start of the program as predictors of completion. The results indicate that (1) mindfulness is unrelated to completion, while (2) resilience is positively related to completion, and (3) The results indicate that mindfulness is generally unrelated to completion, while resilience generally predicts completion.


Assuntos
Militares , Atenção Plena , Resiliência Psicológica , Humanos , Militares/psicologia , Militares/educação , Masculino , Estudos Longitudinais , Adulto , Feminino , Adulto Jovem
19.
Dokl Biol Sci ; 518(1): 107-111, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39128949

RESUMO

Tissue contamination with persistent organic pollutants (POPs) in organisms proved possible to comprehensively characterize in a single test by combining gas chromatography and high-resolution accurate mass spectrometry. Adipose tissue samples were collected from two Caspian seals (Pusa caspica Gmelin, 1788) found dead on the Caspian Sea shore in 2020. Organochlorine pesticides, primarily DDT and HCH, and polychlorinated biphenyls (PCBs) were major pollutants found in the Caspian seals. The distribution of metabolites indicated the absence of recent pesticide use. The PCB content was relatively high, but still at the lower limit of the range of values determined previously, as was also the case with pesticides. Chlordanes, polychlorinated naphthalenes, and polybrominated diphenyl ethers were detected in minor quantities and were therefore not considered to be major pollutants of the Caspian seal. The pollutant levels were below a threshold at which a distinct effect on seal health can be expected. High-resolution accurate mass (HRAM) spectrometry was found to provide a convenient tool for both targeted and nontargeted analyses of a wide range of organic pollutants in a single experiment.


Assuntos
Tecido Adiposo , Bifenilos Policlorados , Focas Verdadeiras , Animais , Tecido Adiposo/metabolismo , Tecido Adiposo/química , Focas Verdadeiras/metabolismo , Bifenilos Policlorados/análise , Poluentes Químicos da Água/análise , Poluentes Orgânicos Persistentes/metabolismo , Espectrometria de Massas/métodos , Monitoramento Ambiental/métodos , Hidrocarbonetos Clorados/análise , Praguicidas/análise
20.
Stomatologiia (Mosk) ; 103(4): 67-69, 2024.
Artigo em Russo | MEDLINE | ID: mdl-39171346

RESUMO

OBJECTIVE: To reveal need for prosthodontics in permanent teeth in children aged 8-18 years. MATERIALS AND METHODS: The study was performed in Khimki Dental Municipal Clinic. Dental examination and radiological studies were conducted in 97 primary patients aged 8-18 years. Indications for prosthodontics in permanent teeth were occlusal deterioration index more than 40% and crown decay of more than 50% in incisors and canines. Additional features were registered including DMFT index, the presence of extracted teeth and teeth after root canal treatment, as well and teeth with extensive restorations with resins and marginal seal quality. RESULTS: From 97 primary patients (27.8%) children needed prosthodontics in permanent teeth (in average 2.3±2.1 teeth): 1 tooth in 10 children, 2 teeth in 11 children, 3 teeth in 1 child, 4 teeth in 3 children and 4 teeth in 2 children. Mean DMFT was 8.1±4.5 teeth. Six children already had extracted permanent teeth (9 teeth in total). Half of the teeth (49.2%) which needed orthodontic treatment had history of root canal treatment while 46% needed primary or secondary endodontic treatment. Occlusal deterioration index was more than 40% in 41.3% of cases, more than 60% in 49.2% of teeth and more than 80% in 9.52% of teeth. From all the teeth restored with composite resins 41.7% had good marginal seal but 58.3% showed macroscopic signs of marginal leakage. CONCLUSION: Our study shows high percentage of adolescents having need for prosthodontics in permanent teeth and unjustified widening of indications for direct resin restorations in this group of patients.


Assuntos
Dentição Permanente , Humanos , Criança , Adolescente , Masculino , Feminino , Cárie Dentária/terapia , Cárie Dentária/epidemiologia , Restauração Dentária Permanente/estatística & dados numéricos , Restauração Dentária Permanente/métodos , Tratamento do Canal Radicular/estatística & dados numéricos , Prostodontia/métodos , Índice CPO
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