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1.
CNS Neurosci Ther ; 30(9): e70025, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39228080

RESUMO

AIMS: The study aimed to evaluate the potential benefits of luteolin treatment in Huntington's disease (HD), an inherited progressive neurodegenerative disorder. METHODS: HD N171-82Q transgenic and WT mice received luteolin or vehicle for treatment at 6 weeks of age. The mice's body weight changes and survival rates were monitored throughout the study, and a series of motor functional tests were conducted. Serum level of the marker NfL was also determined. Immunohistochemical staining and western blotting were utilized to assess the expression of huntingtin aggregates. RESULTS: Luteolin treatment enhanced survival and prevented weight loss in HD mice compared to the vehicle-treated HD group. Furthermore, the luteolin-treated HD mice exhibited enhanced motor coordination and balance and significantly reduced motor dysfunction. Also, luteolin decreased serum NfL levels in HD mice. Notably, the accumulation of huntingtin aggregates was significantly reduced in the brain's cortex, hippocampus, and striatum of luteolin-treated HD mice compared to the vehicle-treated HD group. CONCLUSION: Luteolin holds promise as a therapeutic agent for improving survival outcomes, managing motor dysfunction, and reducing huntingtin aggregates in HD. The findings are of significance as currently, there are no approved therapeutic interventions that reverse HD pathology or slow down its progression.


Assuntos
Modelos Animais de Doenças , Proteína Huntingtina , Doença de Huntington , Luteolina , Camundongos Transgênicos , Animais , Doença de Huntington/tratamento farmacológico , Doença de Huntington/metabolismo , Luteolina/farmacologia , Luteolina/uso terapêutico , Camundongos , Proteína Huntingtina/genética , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Proteínas de Neurofilamentos/metabolismo , Masculino , Atividade Motora/efeitos dos fármacos , Humanos
2.
Curr Biol ; 34(17): 4033-4038.e5, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39106864

RESUMO

Having a profound influence on marine and coastal environments worldwide, jellyfish hold significant scientific, economic, and public interest.1,2,3,4,5 The predictability of outbreaks and dispersion of jellyfish is limited by a fundamental gap in our understanding of their movement. Although there is evidence that jellyfish may actively affect their position,6,7,8,9,10 the role of active swimming in controlling jellyfish movement, and the characteristics of jellyfish swimming behavior, are not well understood. Consequently, jellyfish are often regarded as passively drifting or randomly moving organisms, both conceptually2,11 and in process studies.12,13,14 Here we show that the movement of jellyfish is modulated by distinctly directional swimming patterns that are oriented away from the coast and against the direction of surface gravity waves. Taking a Lagrangian viewpoint from drone videos that allows the tracking of multiple adjacent jellyfish, and focusing on the scyphozoan jellyfish Rhopilema nomadica as a model organism, we show that the behavior of individual jellyfish translates into a synchronized directional swimming of the aggregation as a whole. Numerical simulations show that this counter-wave swimming behavior results in biased correlated random-walk movement patterns that reduce the risk of stranding, thus providing jellyfish with an adaptive advantage critical to their survival. Our results emphasize the importance of active swimming in regulating jellyfish movement and open the way for a more accurate representation in model studies, thus improving the predictability of jellyfish outbreaks and their dispersion and contributing to our ability to mitigate their possible impact on coastal infrastructure and populations.


Assuntos
Cifozoários , Natação , Animais , Natação/fisiologia , Cifozoários/fisiologia
3.
Biol Lett ; 20(8): 20240292, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39106945

RESUMO

Human disturbances can prompt natural anti-predator behaviours in animals, affecting how energy is traded off between immediate survival and reproduction. In our study of male squaretail groupers (Plectropomus areolatus) in India's Lakshadweep archipelago, we investigated the impact of fishing pressure on anti-predatory responses and reproductive behaviours by comparing a fished and unfished spawning aggregation site and tracking responses over time at the fished site. Using observational sampling and predator exposure experiments, we analysed fear responses (flight initiation distance, return time), as well as time spent in vigilance, courtship and territorial defence. Unpaired males at fished sites were twice as likely to flee from simulated predators and took longer to return to mating territories. In contrast, paired males at both sites took greater risks during courtship, fleeing later than unpaired males, but returned earlier at the unfished site compared with the fished site. Our findings suggest that high fishing pressure reduces reproductive opportunities by increasing vigilance and compromising territorial defence, potentially affecting mate selection cues. Altered behavioural trade-offs may mitigate short-term capture risk but endanger long-term population survival through altered reproductive investment. Human extractive practices targeting animal reproductive aggregations can have disruptive effects beyond direct removal, influencing animal behaviours crucial for population survival.


Assuntos
Pesqueiros , Reprodução , Animais , Masculino , Reprodução/fisiologia , Índia , Comportamento Sexual Animal/fisiologia , Territorialidade
4.
Ageing Res Rev ; 100: 102386, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38969143

RESUMO

Neurodegenerative disorders (NDs) such as Alzheimer's disease, Parkinson's disease, Huntington's disease, multiple sclerosis, and amyotrophic lateral sclerosis are severe and life-threatening conditions in which significant damage of functional neurons occurs to produce psycho-motor malfunctions. NDs are an important cause of death in the elderly population worldwide. These disorders are commonly associated with the progression of age, oxidative stress, and environmental pollutants, which are the major etiological factors. Abnormal aggregation of specific proteins such as α-synuclein, amyloid-ß, huntingtin, and tau, and accumulation of the associated oligomers in neurons are the hallmark pathological features of NDs. Existing therapeutic options for NDs are only symptomatic relief and do not address root-causing factors, such as protein aggregation, oxidative stress, and neuroinflammation. Cannabidiol (CBD) is a non-psychotic natural cannabinoid obtained from Cannabis sativa that possesses multiple pharmacological actions, including antioxidant, anti-inflammatory, and neuroprotective effects in various NDs and other neurological disorders both in vitro and in vivo. CBD has gained attention as a promising drug candidate for the management of neurodegenerative disorders, such as Alzheimer's disease and Parkinson's disease, by inhibiting protein aggregation, free radicals, and neuroinflammation. In parallel, CBD has shown positive results in other neurological disorders, such as epilepsy, depression, schizophrenia, and anxiety, as well as adjuvant treatment with existing standard therapeutic agents. Hence, the present review focuses on exploring the possible molecular mechanisms in controlling various neurological disorders as well as the clinical applications of CBD in NDs including epilepsy, depression and anxiety. In this way, the current review will serve as a standalone reference for the researchers working in this area.


Assuntos
Canabidiol , Doenças Neurodegenerativas , Humanos , Canabidiol/uso terapêutico , Canabidiol/farmacologia , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/metabolismo , Animais , Fármacos Neuroprotetores/uso terapêutico , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos
5.
J Fish Biol ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39030783

RESUMO

Understanding the spawning behavior of meagre (Argyrosomus regius) is crucial for fisheries management and conservation. Meagre forms large spawning aggregations in estuaries, yet details of its spawning grounds remain elusive. We tagged 41 individuals and monitored their movements throughout several spawning seasons. Detections inside estuaries were limited. Fish detected inside the Tejo estuary during the spawning season performed regular movements toward coastal areas, suggesting potential spawning outside estuaries. Our findings underscore the significance of understanding meagre's migratory patterns for effective fisheries management and conservation strategies, supporting the establishment of spatial and seasonal closures during the spawning season.

6.
PeerJ ; 12: e16891, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38500525

RESUMO

Background: Like many cockroaches, Argentinian wood roaches, Blaptica dubia, prefer darker shelters over lighter shelters. In three experiments, we asked whether chemical cues from other roaches might influence shelter choice, a process known as conspecific or heterospecific cueing, depending on whether the cues come from an individual of the same or a different species, respectively. Methods: Each experiment involved trials with focal B. dubia cockroaches in testing arenas containing plastic shelters of varying levels of darkness, with filter paper under each shelter acting as a carrier for chemical cues. In Experiment 1, we tested female and male B. dubia cockroaches with two shelters matched for darkness but differing in cues (conspecific vs. none). The shelter with no cue contained a blank filter paper as a control. In Experiment 2 (conspecific cueing) and Experiment 3 (heterospecific cueing), we tested B. dubia cockroach choices for lighter or darker shelters with filter papers containing chemical cues of other roaches or no chemical cues. For the conspecific cueing study of Experiment 2, we used chemical cues from other B. dubia cockroaches. In contrast, for the heterospecific cueing study of Experiment 3, we used chemical cues from a different species, the death's head cockroach, Blaberus craniifer. Results: In Experiment 1, B. dubia cockroaches overwhelmingly preferred shelters with conspecific chemical cues over darkness-matched shelters without cues. In Experiments 2 and 3, they strongly preferred darker shelters, especially when chemical cues were present. Additionally, they were more likely to be under the lighter shelter when chemical cues were present there. These results reveal that the public information B. dubia cockroaches gain from chemical cues-including those from other species-can drive shelter choices in this species.


Assuntos
Baratas , Animais , Masculino , Feminino , Sinais (Psicologia)
7.
Proteins ; 92(9): 1070-1084, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38497314

RESUMO

Human islet amyloid polypeptide (amylin or hIAPP) is a 37 residue hormone co-secreted with insulin from ß cells of the pancreas. In patients suffering from type-2 diabetes, amylin self-assembles into amyloid fibrils, ultimately leading to the death of the pancreatic cells. However, a research gap exists in preventing and treating such amyloidosis. Plumbagin, a natural compound, has previously been demonstrated to have inhibitory potential against insulin amyloidosis. Our investigation unveils collapsible regions within hIAPP that, upon collapse, facilitates hydrophobic and pi-pi interactions, ultimately leading to aggregation. Intriguingly plumbagin exhibits the ability to bind these specific collapsible regions, thereby impeding the aforementioned interactions that would otherwise drive hIAPP aggregation. We have used atomistic molecular dynamics approach to determine secondary structural changes. MSM shows metastable states forming native like hIAPP structure in presence of PGN. Our in silico results concur with in vitro results. The ThT assay revealed a striking 50% decrease in fluorescence intensity at a 1:1 ratio of hIAPP to Plumbagin. This finding suggests a significant inhibition of amyloid fibril formation by plumbagin, as ThT fluorescence directly correlates with the presence of these fibrils. Further TEM images revealed disappearance of hIAPP fibrils in plumbagin pre-treated hIAPP samples. Also, we have shown that plumbagin disrupts the intermolecular hydrogen bonding in hIAPP fibrils leading to an increase in the average beta strand spacing, thereby causing disaggregation of pre-formed fibrils demonstrating overall disruption of the aggregation machinery of hIAPP. Our work is the first to report a detailed atomistic simulation of 22 µs for hIAPP. Overall, our studies put plumbagin as a potential candidate for both preventive and therapeutic candidate for hIAPP amyloidosis.


Assuntos
Polipeptídeo Amiloide das Ilhotas Pancreáticas , Simulação de Dinâmica Molecular , Naftoquinonas , Naftoquinonas/química , Naftoquinonas/farmacologia , Polipeptídeo Amiloide das Ilhotas Pancreáticas/química , Polipeptídeo Amiloide das Ilhotas Pancreáticas/metabolismo , Polipeptídeo Amiloide das Ilhotas Pancreáticas/antagonistas & inibidores , Humanos , Cadeias de Markov , Ligação Proteica , Interações Hidrofóbicas e Hidrofílicas , Agregados Proteicos/efeitos dos fármacos , Ligação de Hidrogênio
8.
Methods Mol Biol ; 2770: 99-111, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38351449

RESUMO

In vitro induction of primordial germ cell like-cells (PGCLCs) from pluripotent stem cells (PSCs) is a robust method that will contribute to understanding the fundamentals of cell fate decisions, animal breeding, and future reproductive medicine. Here, we introduce this system established in the rat model. We describe a stepwise protocol to induce epiblast-like cells and subsequent PGCLCs by forming spherical aggregates from rat PSCs. We also describe a protocol to mature these PGCLCs from specified/migratory to the gonadal stage by aggregation with female gonadal somatic cells.


Assuntos
Células-Tronco Pluripotentes , Ratos , Feminino , Animais , Células Germinativas , Diferenciação Celular , Células Cultivadas , Camadas Germinativas
9.
Parasit Vectors ; 17(1): 58, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336751

RESUMO

BACKGROUND: The ornate dog tick Dermacentor reticulatus is second only to the hard tick Ixodes ricinus in terms of importance as a vector of infectious organisms, especially of Babesia canis, the agent of canine babesiosis. Both the geographical range and local densities of D. reticulatus are steadily increasing in many regions of Europe. In the present study, we tested the hypothesis that D. reticulatus possesses an efficient breeding strategy that allows for a rapid increase in tick numbers and densities through the formation of mixed-sex clusters/aggregations while questing in the environment. METHODS: An observational study was carried out in the spring of 2023, at three sites in two regions in Central and North-Eastern Poland, both characterised by high tick densities. At each site, a 400-m-long transect was inspected for questing ticks. All noted ticks were collected, and tick numbers and sexes per stem were recorded. Differences in tick distribution by site and sex were analysed statistically. RESULTS: A total of 371 D. reticulatus (219 females, 152 males) ticks were collected from 270 grass stems over a combined 1200 m of transect. The majority of grass stems (74.4%) were occupied by just a single individual, with two-tick clusters the second most common category. The maximum number of D. reticulatus individuals observed on a single grass stem was six. Mixed-sex clusters were significantly more common than single-sex clusters at all three sites. With study sites combined, mixed-sex clusters accounted for 17.4% (95% confidence limit [95% CL] 13.9-21.6%) of observations, while for multiple males and multiple females, the values were 2.6% (95% CL: 1.4-4.7%) and 5.6% (95% CL: 3.7-8.3%), respectively. CONCLUSIONS: Mixed-sex clusters of D. reticulatus ticks were significantly more common than single-sex clusters, which we hypothesise reflects an efficient, likely pheromone-mediated breeding strategy of this expansive tick species.


Assuntos
Dermacentor , Rhipicephalus sanguineus , Animais , Cães , Feminino , Masculino , Ixodes , Melhoramento Vegetal , Polônia/epidemiologia
10.
Macromol Rapid Commun ; 45(1): e2300288, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37528653

RESUMO

Tailoring the crystal orientation of donor-acceptor (D-A) copolymers is vital for boosting the performance of optoelectronic devices. Despite recent advances in controlling the crystal orientation of D-A copolymers in films, the investigation into their aggregates in solution and the correlation between the solution aggregates and solid-state crystal orientation has been limited. Herein, an effective solvent additive strategy is reported for tuning solution aggregates and the consequent solid-state structures of poly{[N,N'-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5'-(2,2'-bithiophene)} (P(NDI2OD-T2)). Specifically, the addition of 1-decanethiol (10-thiol) to the P(NDI2OD-T2) chloroform solution promoted the aggregation of P(NDI2OD-T2) chains because of the improved planarization of the backbones, which changed their crystal orientation in the film from coexisting edge-on and face-on to dominant edge-on when produced by drop-casting. The mechanism of this crystal orientation transformation is elucidated based on the interaction between 10-thiol and the side chains of P(NDI2OD-T2). The optical properties of P(NDI2OD-T2) films with different crystalline structures are closely correlated. Notably, the 10-thiol-enabled facile tailoring of the crystal orientation in P(NDI2OD-T2) can be readily applied to other D-A copolymers of interest. The findings of this study highlight a robust solvent additive strategy for regulating solution aggregates and crystal orientation in D-A copolymer films, which have applications in many optoelectronic devices.


Assuntos
Clorofórmio , Polímeros , Solventes , Compostos de Sulfidrila
11.
Front Immunol ; 14: 1253099, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37876924

RESUMO

In this work, we aimed at investigating cell and tissue responses of the apple snail Pomacea canaliculata, following the inoculation of the zoonotic pathogen Mycobacterium marinum. Different doses were tested (10, 20, 65, and 100 M CFU) and the mortality rate was negligible. The histopathogenesis was followed at 4, 9, and 28 days after inoculation. Overt histopathological lesions were consistently observed after the two largest doses only. In the lung, marked hemocyte aggregations, including intravascular nodule formation, were observed within the large blood veins that run along the floor and roof of this organ. Hemocyte aggregations were found occluding many of the radial sinuses supplying the respiratory lamina. Acid-fast bacilli were contained in the different hemocyte aggregations. In addition, hemocytes were observed infiltrating the storage tissue, which makes up most of the lung wall, and the connective tissue of the mantle edge. Additionally, signs of degradation in the storage tissue were observed in the lung wall on day 28. In the kidney, nodules were formed associated with the constitutive hemocyte islets and with the subpallial hemocoelic space, in whose hemocytes the acid-fast structures were found. Electron microscopy analysis revealed the presence of bacteria-containing phagosomes within hemocytes located in the surface zone of the islets. Additionally, electron-dense spheroidal structures, which are likely remnants of digested mycobacteria, were observed in close proximity to the hemocytes' nuclei. The size attained by the hemocyte nodules varied during the observation period, but there was no clear dependence on dose or time after inoculation. Nodules were also formed subpallially. Some of these nodules showed 2-3 layers with different cellular composition, suggesting they may also form through successive waves of circulating cells reaching them. Nodular cores, including those formed intravascularly in the lung, would exhibit signs of hemocyte dedifferentiation, possibly proliferation, and death. Hemocyte congestion was observed in the hemocoelic spaces surrounding the pallial ends of the renal crypts, and the renal crypts themselves showed de-epithelization, particularly on day 28. The diverse cellular responses of P. canaliculata to M. marinum inoculation and the high resilience of this snail to the pathogen make it a suitable species for studying mycobacterial infections and their effects on cellular and physiological processes.


Assuntos
Hemócitos , Caramujos , Animais , Microscopia Eletrônica , Fagossomos , Pulmão
12.
Bioengineering (Basel) ; 10(9)2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37760122

RESUMO

Arterial thrombosis (AT) originates through platelet-mediated thrombus formation in the blood vessel and can lead to heart attack, stroke, and peripheral vascular diseases. Restricting the thrombus growth and its simultaneous monitoring by visualisation is an unmet clinical need for a better AT prognosis. As a proof-of-concept, we have engineered a nanoparticle-based theranostic (combined therapy and monitoring) platform that has the potential to monitor and restrain the growth of a thrombus concurrently. The theranostic nanotool is fabricated using biocompatible super-paramagnetic iron oxide nanoparticles (SPIONs) as a core module tethered with the anti-platelet agent Abciximab (ReoPro) on its surface. Our in vitro feasibility results indicate that ReoPro-conjugated SPIONS (Tx@ReoPro) can effectively prevent thrombus growth by inhibiting fibrinogen receptors (GPIIbIIIa) on the platelet surface, and simultaneously, it can also be visible through non-invasive magnetic resonance imaging (MRI) for potential reporting of the real-time thrombus status.

13.
Adv Healthc Mater ; 12(29): e2301595, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37557912

RESUMO

Low-density lipoprotein (LDL), especially oxidative modified LDL (Ox-LDL), is the key risk factor for plaque accumulation and the development of cardiovascular disease. Herein, a highly specific Ox-LDL-triggered fluorogenic-colorimetric probe Pro-P1 is developed for visualizing the oxidation and aggregation progress of lipoproteins and plaque. A series of green fluorescent protein chromophores with modified donor-acceptor structures, containing carbazole as an electron donor and various substituents including pyridine-vinyl (P1), phenol-vinyl (P2), N, N-dimethylaniline-vinyl (P3), and thiophene-vinyl (P4), have been synthesized and evaluated. Emission spectroscopy and theoretical calculations of P1-P4 indicate that P1 shows enhanced green fluorescence (λem = 560 nm) by inhibiting its twisted intramolecular charge transfer in the presence of Ox-LDL. This feature allows the selection of P1 as a sensitive probe to directly visualize ferroptosis and Cu2+ -mediated LDL oxidative aggregation via in situ formation of fluorophore-bound Ox-LDL in living cells. The red-emissive probe Pro-P1 (λem = 660 nm) is prepared via borate protection of P1, which can be cleaved into P1 under high expression of HOCl and Ox-LDL condition at the lesion site, resulting in enhanced green emission. The plaque area and size with clear boundaries can be delineated by colorimetric fluorescence imaging and fluorescence lifetime imaging with precise differentiation.


Assuntos
Placa Aterosclerótica , Humanos , Placa Aterosclerótica/diagnóstico por imagem , Lipoproteínas LDL/química , Lipoproteínas LDL/metabolismo , Lipoproteínas/metabolismo , Oxirredução
14.
J Phycol ; 59(5): 939-949, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37572353

RESUMO

Cryoconite, the dark sediment on the surface of glaciers, often aggregates into oval or irregular granules serving as biogeochemical factories. They reduce a glacier's albedo, act as biodiversity hotspots by supporting aerobic and anaerobic microbial communities, constitute one of the organic matter (OM) sources on glaciers, and are a feeder for micrometazoans. Although cryoconite granules have multiple roles on glaciers, their formation is poorly understood. Cyanobacteria are ubiquitous and abundant engineers of cryoconite hole ecosystems. This study tested whether cyanobacteria may be responsible for cryoconite granulation as a sole biotic element. Incubation of Greenlandic, Svalbard, and Scandinavian cyanobacteria in different nutrient availabilities and substrata for growth (distilled water alone and water with quartz powder, furnaced cryoconite without OM, or powdered rocks from glacial catchment) revealed that cyanobacteria bind mineral particles into granules. The structures formed in the experiment resembled those commonly observed in natural cryoconite holes: they contained numerous cyanobacterial filaments protruding from aggregated mineral particles. Moreover, all examined strains were confirmed to produce extracellular polymeric substances (EPS), which suggests that cryoconite granulation is most likely due to EPS secretion by gliding cyanobacteria. In the presence of water as the only substrate for growth, cyanobacteria formed mostly carpet-like mats. Our data empirically prove that EPS-producing oscillatorialean cyanobacteria isolated from the diverse community of cryoconite microorganisms can form granules from mineral substrate and that the presence of the mineral substrate increases the probability of the formation of these important and complex biogeochemical microstructures on glaciers.


Assuntos
Cianobactérias , Microbiota , Camada de Gelo/química , Camada de Gelo/microbiologia , Clima Frio , Cianobactérias/metabolismo , Minerais/metabolismo , Água
15.
Nanotechnology ; 34(40)2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37399801

RESUMO

We report on the formation of bendable and edge-on poly[3-(4-carboxybutyl)thiophene-2,5-diyl] (P3CT) polymers thin layer used as a hole modification layer (HML) in the inverted perovskite solar cell. The aggregations of 2D layer-like P3CT polymers in dimethylformamide (DMF) solution can be formed via aromaticπ-πstacking interactions and/or hydrogen-bonding interactions with the different concentration from 0.01 to 0.02 wt%, which highly influences the photovoltaic performance of the inverted perovskite solar cells. The atomic-force microscopic images and water droplet contact angle images show that the P3CT polymers modify the surface properties of the transparent conductive substrate and thereby dominating the formation of perovskite crystalline thin films, which play important roles in the highly efficient and stable perovskite solar cells. It is noted that theVOC(JSC) of the encapsulated solar cells values are maintained to be higher than 1.115 V (22 mA cm-2) after 104 d when an optimizedπ-πstacked and hydrogen-bonded P3CT polymer is used as the HML. On the other hand, the solar cell showed a high long-term stability by maintaining 85% of the initial power conversion efficiency in the ambient air for 103 d.

16.
Adv Mater ; 35(51): e2305652, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37523613

RESUMO

The ternary strategy has been intensively studied to improve the power conversion efficiencies of organic photovoltaics. Thereinto, the location of the guest component plays a critical role, but few reports have been devoted to this concern. Hereon, the distribution of LA1 as a guest acceptor in a variety of ternary scenarios is reported and the dominating driving forces of managing the guest distribution and operating modes are outlined. Governed by the appropriate relationship of compatibility, crystallinity, and surface energies between host and guest acceptors, as well as interfacial interactions between donor and dual acceptors, most of the LA1 molecules permeate into the internal of host acceptor phases, forming embedded host/guest alloy-like aggregations. The characteristic distributions greatly optimize the morphologies, maximize energy transfer, and enhance exciton/charge behaviors. Particularly, PM6:IT-4F:LA1 ternary cells afford high efficiency of 15.27% with impressive fill factors (FF) over 81%. The popularization studies further verify the superiority of the LA1-involved alloy structures, and with the Y6-family acceptor as the host component, an outstanding efficiency of 19.17% is received. The results highlight the importance of guest distribution in ternary systems and shed light on the governing factors of distributing the guests in ternary cells.

17.
Philos Trans R Soc Lond B Biol Sci ; 378(1878): 20220103, 2023 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-37066648

RESUMO

The open ocean offers a suite of ecological conditions promoting the occurrence of multi-species predator aggregations. These mixed predator aggregations typically hunt large groups of relatively small and highly cohesive prey. However, the mechanisms and functions of these mixed predator aggregations are largely unknown. Even basic knowledge of whether the predator species' interactions are mutualistic, commensal or parasitic is typically missing. Moreover, recordings of attack and capture rates of marine multi-species predator aggregations, which are critical in understanding how and why these interactions have evolved, are almost completely non-existent owing to logistical challenges. Using underwater video, we quantified the attack and capture rates of two high-trophic level marine predators, California sea lions (Zalophus californianus) and striped marlin (Kajikia audax) attacking schools of fishes in the Southern California Current System, offshore the Baja California Peninsula. Recording over 5000 individual attacks across 13 fish schools, which varied in species, size and predator composition, we found that sea lions kleptoparasitized striped marlin hunts and reduced the frequency of marlin attacks and captures via interference competition. We discuss our results in the context of the phenotypic differences between the predator species and implications for a better understanding of multi-species predator aggregations. This article is part of the theme issue 'Mixed-species groups and aggregations: shaping ecological and behavioural patterns and processes'.


Assuntos
Perciformes , Comportamento Predatório , Leões-Marinhos , Animais , Peixes , México
18.
Chemphyschem ; 24(11): e202300097, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36789861

RESUMO

It is shown that repulsive interactions have a crucial influence on the structure of prototypical non-covalently bonded systems. To explain this, we propose a molecular orbital-based model for the exchange-repulsion contribution to the total interaction energy. As a central result, our model shows that energetically preferred aggregate structures frequently exhibit reduced exchange repulsion, which can be deduced from the nodal structure of certain occupied orbitals. This is used to explain key features of the intermolecular potentials of the Cl2 -He, benzene-benzene, and benzene-hexafluorobenzene aggregates, which are not correctly reproduced by commonly applied electrostatic models.

19.
PeerJ ; 11: e14810, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36751629

RESUMO

Background: Over the past decade, environmental DNA (eDNA) has become a resourceful tool in conservation and biomonitoring. Environmental DNA has been applied in a variety of environments, but the application to studies of marine fish, particularly at tropical latitudes, are limited. Since many commercially important Caribbean fishes are overexploited, these species are optimal candidates to explore the use of this method as a biomonitoring tool. Specifically, for many of these species, the formation of fish spawning aggregations (FSAs) marks a critical life history event where fishes will gather in large numbers for reproduction. These FSAs are ephemeral in nature, lasting only a few days, but are predictable in time and space which makes them susceptible to overfishing. Methods: In this study, we test the feasibility of using an eDNA sampling approach (water and sediment collection) to detect the presence of known FSAs off the west coast of Puerto Rico, with cytochrome c oxidase subunit 1 (CO1) and 12S rRNA (12S) primers designed to target specific species. A total of 290 eDNA samples were collected and, of those, 206 eDNA samples were processed. All eDNA samples varied in DNA concentration, both between replicates and collection methods. A total of 12 primer sets were developed and tested using traditional PCR and qPCR. Results: Despite validation of primer accuracy and sample collection during known peak spawning times, the use of traditional PCR and qPCR with both molecular markers failed to produce species-specific amplification. Thus, a trial test was conducted using the CO1 primers in which target fish DNA was 'spiked' at various concentrations into the respective eDNA samples to determine the target species DNA concentration limit of detection. Upon successful amplification of the trial, results indicated that eDNA samples were below the detection threshold of our methods, suggesting that the number of fish present at the spawning aggregations was inadequate for single-species detection methods. In addition, elements such as the unavoidable presence of non-target DNA, oceanic environmental conditions, shedding rates of target fish, among other biotic and abiotic factors could have affected DNA persistence and degradation rates at the sites. Conclusion: We provide recommendations for species-specific fish detection in lower latitudes, and suggestions for studies aiming to monitor or detect fish spawning aggregations using eDNA sampling.


Assuntos
DNA Ambiental , Animais , Conservação dos Recursos Naturais , Pesqueiros , Peixes/genética , DNA/análise , Porto Rico
20.
J Colloid Interface Sci ; 635: 456-465, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36599243

RESUMO

Compared with the individuals, the collective behavior of biotic communities could show certain superior characteristics. Inspired by this idea and based on the conjugation between phenylboronic acid-grafted mesoporous silica nanoparticles and the polysaccharide functionalized membrane of proteinosomes, a type of proteinosomes-based aggregations was constructed. We demonstrated the emergent characteristics of proteinosomes aggregations including accelerated settling velocity and population surviving by sacrificing outside members for the inside. Moreover, this kind of "hand in hand" architecture provided the proteinosomes aggregations with the characteristic of resistance to the negative pressure phagocytosis of micropipette, as well as enhancing utilization rate of the encapsulated enzymes. Overall, it is anticipated that the construction and application of proteinosomes aggregations could contribute to advance the functionality of life-like assembled biomaterial in another way.

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