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1.
IEEE Trans Vis Comput Graph ; 30(5): 2796-2806, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38437123

RESUMEN

VR devices have recently been actively promoted as tools for knowledge workers and prior work has demonstrated that VR can support some knowledge worker tasks. However, only a few studies have explored the effects of prolonged use of VR such as a study observing 16 participants working in VR and a physical environment for one work-week each and reporting mainly on subjective feedback. As a nuanced understanding of participants' behavior in VR and how it evolves over time is still missing, we report on the results from an analysis of 559 hours of video material obtained in this prior study. Among other findings, we report that (1) the frequency of actions related to adjusting the headset reduced by 46% and the frequency of actions related to supporting the headset reduced by 42% over the five days; (2) the HMD was removed 31% less frequently over the five days but for 41% longer periods; (3) wearing an HMD is disruptive to normal patterns of eating and drinking, but not to social interactions, such as talking. The combined findings in this work demonstrate the value of long-term studies of deployed VR systems and can be used to inform the design of better, more ergonomic VR systems as tools for knowledge workers.


Asunto(s)
Realidad Virtual , Humanos , Gráficos por Computador , Retroalimentación
2.
Nat Commun ; 15(1): 1251, 2024 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-38341437

RESUMEN

Organismal functional strategies form a continuum from slow- to fast-growing organisms, in response to common drivers such as resource availability and disturbance. However, whether there is synchronisation of these strategies at the entire community level is unclear. Here, we combine trait data for >2800 above- and belowground taxa from 14 trophic guilds spanning a disturbance and resource availability gradient in German grasslands. The results indicate that most guilds consistently respond to these drivers through both direct and trophically mediated effects, resulting in a 'slow-fast' axis at the level of the entire community. Using 15 indicators of carbon and nutrient fluxes, biomass production and decomposition, we also show that fast trait communities are associated with faster rates of ecosystem functioning. These findings demonstrate that 'slow' and 'fast' strategies can be manifested at the level of whole communities, opening new avenues of ecosystem-level functional classification.


Asunto(s)
Biodiversidad , Ecosistema , Biomasa , Agricultura , Suelo
3.
Nat Commun ; 15(1): 1084, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38316781

RESUMEN

When an inverted ensemble of atoms is tightly packed on the scale of its emission wavelength or when the atoms are collectively strongly coupled to a single cavity mode, their dipoles will align and decay rapidly via a superradiant burst. However, a spread-out dipole phase distribution theory predicts a required minimum threshold of atomic excitation for superradiance to occur. Here we experimentally confirm this predicted threshold for superradiant emission on a narrow optical transition when exciting the atoms transversely and show how to take advantage of the resulting sub- to superradiant transition. A π/2-pulse places the atoms in a subradiant state, protected from collective cavity decay, which we exploit during the free evolution period in a corresponding Ramsey pulse sequence. The final excited state population is read out via superradiant emission from the inverted atomic ensemble after a second π/2-pulse, and with minimal heating this allows for multiple Ramsey sequences within one experimental cycle. Our scheme is an innovative approach to atomic state readout characterized by its speed, simplicity, and highly directional emission of signal photons. It demonstrates the potential of sensors using collective effects in cavity-coupled quantum emitters.

4.
Ecol Lett ; 27(1): e14336, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38073071

RESUMEN

Biodiversity-ecosystem functioning (BEF) research has provided strong evidence and mechanistic underpinnings to support positive effects of biodiversity on ecosystem functioning, from single to multiple functions. This research has provided knowledge gained mainly at the local alpha scale (i.e. within ecosystems), but the increasing homogenization of landscapes in the Anthropocene has raised the potential that declining biodiversity at the beta (across ecosystems) and gamma scales is likely to also impact ecosystem functioning. Drawing on biodiversity theory, we propose a new statistical framework based on Hill-Chao numbers. The framework allows decomposition of multifunctionality at gamma scales into alpha and beta components, a critical but hitherto missing tool in BEF research; it also allows weighting of individual ecosystem functions. Through the proposed decomposition, new BEF results for beta and gamma scales are discovered. Our novel approach is applicable across ecosystems and connects local- and landscape-scale BEF assessments from experiments to natural settings.


Asunto(s)
Biodiversidad , Ecosistema
5.
Nature ; 628(8007): 349-354, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37758943

RESUMEN

Insects have a pivotal role in ecosystem function, thus the decline of more than 75% in insect biomass in protected areas over recent decades in Central Europe1 and elsewhere2,3 has alarmed the public, pushed decision-makers4 and stimulated research on insect population trends. However, the drivers of this decline are still not well understood. Here, we reanalysed 27 years of insect biomass data from Hallmann et al.1, using sample-specific information on weather conditions during sampling and weather anomalies during the insect life cycle. This model explained variation in temporal decline in insect biomass, including an observed increase in biomass in recent years, solely on the basis of these weather variables. Our finding that terrestrial insect biomass is largely driven by complex weather conditions challenges previous assumptions that climate change is more critical in the tropics5,6 or that negative consequences in the temperate zone might only occur in the future7. Despite the recent observed increase in biomass, new combinations of unfavourable multi-annual weather conditions might be expected to further threaten insect populations under continuing climate change. Our findings also highlight the need for more climate change research on physiological mechanisms affected by annual weather conditions and anomalies.


Asunto(s)
Ecosistema , Tiempo (Meteorología) , Animales , Biomasa , Estaciones del Año , Insectos/fisiología , Cambio Climático
6.
Methods Mol Biol ; 2743: 43-56, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38147207

RESUMEN

Alteration of protein tyrosine phosphatase (PTP) gene expression is a commonly used approach to experimentally analyze their function in the cell physiology of mammalian cells. Here, exemplified for receptor-type PTPRJ (Dep-1, CD148) and PPTRC (CD45), we provide the CRISPR/Cas9-mediated approaches for their inactivation and transcriptional activation using genome editing. These methods are generally applicable to any other protein of interest.


Asunto(s)
Sistemas CRISPR-Cas , Edición Génica , Animales , Sistemas CRISPR-Cas/genética , Activación Transcripcional , Mamíferos
7.
Commun Biol ; 6(1): 1052, 2023 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-37935790

RESUMEN

Urbanization and agricultural intensification are considered the main causes of recent insect decline in temperate Europe, while direct climate warming effects are still ambiguous. Nonetheless, higher temperatures advance spring leaf emergence, which in turn may directly or indirectly affect insects. We therefore investigated how Sentinel-2-derived start of season (SOS) and its spatial variability (SV-SOS) are affected by spring temperature and whether these green-up variables can explain insect biomass and richness across a climate and land-use gradient in southern Germany. We found that the effects of both spring green-up variables on insect biomass and richness differed between land-use types, but were strongest in forests. Here, insect richness and biomass were higher with later green-up (SOS) and higher SV-SOS. In turn, higher spring temperatures advanced SOS, while SV-SOS was lower at warmer sites. We conclude that with a warming climate, insect biomass and richness in forests may be affected negatively due to earlier and more uniform green-up. Promising adaptation strategies should therefore focus on spatial variability in green-up in forests, thus plant species and structural diversity.


Asunto(s)
Clima , Bosques , Animales , Estaciones del Año , Biomasa , Insectos
9.
Nat Commun ; 14(1): 6191, 2023 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-37848442

RESUMEN

Tropical forest recovery is fundamental to addressing the intertwined climate and biodiversity loss crises. While regenerating trees sequester carbon relatively quickly, the pace of biodiversity recovery remains contentious. Here, we use bioacoustics and metabarcoding to measure forest recovery post-agriculture in a global biodiversity hotspot in Ecuador. We show that the community composition, and not species richness, of vocalizing vertebrates identified by experts reflects the restoration gradient. Two automated measures - an acoustic index model and a bird community composition derived from an independently developed Convolutional Neural Network - correlated well with restoration (adj-R² = 0.62 and 0.69, respectively). Importantly, both measures reflected composition of non-vocalizing nocturnal insects identified via metabarcoding. We show that such automated monitoring tools, based on new technologies, can effectively monitor the success of forest recovery, using robust and reproducible data.


Asunto(s)
Aprendizaje Profundo , Animales , Clima Tropical , Bosques , Biodiversidad , Árboles , Ecosistema , Conservación de los Recursos Naturales
10.
Ecology ; 104(12): e4184, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37787980

RESUMEN

Biodiversity drives ecosystem processes, but its influence on deadwood decomposition is poorly understood. To test the effects of insect diversity on wood decomposition, we conducted a mesocosm experiment manipulating the species richness and functional diversity of beetles. We applied a novel approach using computed tomography scanning to quantify decomposition by insects and recorded fungal and bacterial communities. Decomposition rates increased with both species richness and functional diversity of beetles, but the effects of functional diversity were linked to beetle biomass, and to the presence of one large-bodied species in particular. This suggests that mechanisms behind observed biodiversity effects are the selection effect, which is linked to the occurrence probability of large species, and the complementarity effect, which is driven by functional differentiation among species. Additionally, beetles had significant indirect effects on wood decomposition via bacterial diversity, fungal community composition, and fungal biomass. Our experiment shows that wood decomposition is driven by beetle diversity and its interactions with bacteria and fungi. This highlights that both insect and microbial biodiversity are critical to maintaining ecosystem functioning.


Asunto(s)
Escarabajos , Madera , Animales , Madera/microbiología , Ecosistema , Insectos , Biodiversidad , Bacterias
11.
Ecol Evol ; 13(10): e10588, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37869428

RESUMEN

Functional trait approaches are common in ecology, but a lack of clear hypotheses on how traits relate to environmental gradients (i.e., trait-niche relationships) often makes uncovering mechanisms difficult. Furthermore, measures of community functional structure differ in their implications, yet inferences are seldom compared among metrics. Community-weighted mean trait values (CWMs), a common measure, are largely driven by the most common species and thus do not reflect community-wide trait-niche relationships per se. Alternatively, trait-niche relationships can be estimated across a larger group of species using hierarchical joint species distribution models (JSDMs), quantified by a parameter Γ. We investigated how inferences about trait-niche relationships are affected by the choice of metric. Using deadwood-dependent (saproxylic) beetles in fragmented Finnish forests, we followed a protocol for investigating trait-niche relationships by (1) identifying environmental filters (climate, forest age, and deadwood volume), (2) relating these to an ecological function (dispersal ability), and (3) identifying traits related to this function (wing morphology). We tested 18 hypothesized dispersal relationships using both CWM and Γ estimates across these environmental gradients. CWMs were more likely than Γ to show support for trait-niche relationships. Up to 13% of species' realized niches were explained by dispersal traits, but the directions of effects were consistent with fewer than 11%-39% of our 18 trait-niche hypotheses (depending on the metric used). This highlights the difficulty in connecting morphological traits and ecological functions in insects, despite the clear conceptual link between landscape connectivity and flight-related traits. Caution is thus warranted in hypothesis development, particularly where apparent trait-function links are less clear. Inferences differ when CWMs versus Γ estimates are used, necessitating the choice of a metric that reflects study questions. CWMs help explain the effects of environmental gradients on community trait composition, whereas the effects of traits on species' niches are better estimated using hierarchical JSDMs.

12.
Nat Commun ; 14(1): 6396, 2023 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-37828042

RESUMEN

Quantum noise reduction and entanglement-enhanced sensing in the acoustic frequency range is an outstanding challenge relevant for a number of applications including magnetometry and broadband noise reduction in gravitational wave detectors. Here we experimentally demonstrate quantum behavior of a macroscopic atomic spin oscillator in the acoustic frequency range. Quantum back-action of the spin measurement, ponderomotive squeezing of light, and virtual spring softening are observed at oscillation frequencies down to the sub-kHz range. Quantum noise sources characteristic of spin oscillators operating in the near-DC frequency range are identified and means for their mitigation are presented.

13.
J Cancer Res Clin Oncol ; 149(19): 17051-17069, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37750956

RESUMEN

PURPOSE: Sarcomas are a heterogeneous group of malignant neoplasms with a wide range of histological types and occur in almost any anatomic site and side. This study evaluated the prognostic factors in sarcoma patients based on German clinical cancer registry data. METHODS: The German clinical cancer register of Saxony-Anhalt was used for all data analyses. Sarcoma cases of all clinical or pathological T-stages (T1a-T4c), all N-stages (N0-3) and M-stages (0-1b) corresponding to the Union for International Cancer Control (UICC) stages I to IVB were considered. In our analyses, 787 cases diagnosed between 2005 and 2022 were included. Further, we assessed the association of cancer-related parameters with mortality and hazard ratios (HR) from the Cox proportional hazard models. We included sex, age at diagnosis, histological grade, T-, N- and M-stages, tumor size, tumor localization and tumor side as parameters in our regression models. RESULTS: The majority of sarcoma patients were diagnosed with leiomyosarcoma (12%), liposarcoma (11%), angiosarcoma (5.3%) and myxofibrosarcoma (2.7%). In our univariate regression models, tumors localized in more than one location, head, face and neck region as well as the pelvis and lower extremity were associated with increased mortality risk (more than one location: HR 7.10, 95% CI 2.20-22.9; head, face and neck: HR 1.35, 95% CI 0.89-2.06; pelvis: HR 1.27, 95% CI 0.86-1.89; lower extremity: HR 1.44, 95% CI 1.05-1.96). Higher histological grades, UICC-grades and TNM-stages were related to a higher mortality risk. Differing histological subtypes had significant influence on overall survival and progression-free survival. Patients diagnosed with fibromyxoid sarcoma, rhabdomyosarcoma and angiosarcoma were related to higher mortality risk compared to other histological subtypes (fibromyxoid sarcoma: HR 5.2, 95% CI 0.71-38.1; rhabdomyosarcoma: HR 2.93, 95% CI 1.44-6.00; angiosarcoma: HR 1.07, 95% CI 0.53-2.18). CONCLUSIONS: Histological grade, tumor size, nodal and distant metastasis, tumor localization and histological subtype were determined as prognostic factors in terms of survival.


Asunto(s)
Hemangiosarcoma , Leiomiosarcoma , Rabdomiosarcoma , Sarcoma , Neoplasias de los Tejidos Blandos , Adulto , Humanos , Hemangiosarcoma/epidemiología , Sarcoma/patología , Neoplasias de los Tejidos Blandos/patología , Sistema de Registros , Pronóstico , Estudios Retrospectivos
14.
Biol Aujourdhui ; 217(1-2): 103-111, 2023.
Artículo en Francés | MEDLINE | ID: mdl-37409870

RESUMEN

The monitoring of how public opinion memorizes the terrorist attacks from 13th November 2015, and moreover the terrorist attacks since the early 2000s, provides new material for understanding the evolution over time and the mechanisms of the construction of collective memory. Data collected to date show that these attacks had a greater impact on the population than other tragic events that have occurred in recent history in France, or even a greater impact than other and much more recent attacks. In the long term, the precise memory of the factual aspects and the memories of the personal circumstances in which people learned about the events begin to vanish. While imprecision is gaining ground, collective memory now crystallizes on very significant and overdetermined markers such as emblematic places or locations such as the "Bataclan". As a matter of fact, this imprecision of memory goes hand-in-hand with a much stronger symbolic and emotional investment of the event as a whole and leads to an overestimation of the number of terrorists or victims. The special place given to the terrorist attacks of 13th November in the collective memory is due to the unprecedented number of victims, the fact that the attacks took place in the heart of the capital city, the reaction of the public authorities who declared a long lasting state of emergency, the discursive framing of the war on terrorism in all major media, and the feeling that the Islamist threat can kill indiscriminately without targeting specific categories of the population. The study also reveals the influence of value systems (political opinions, views of the republican model) and social characteristics of individuals on the way people memorize such experiences. It is part of a fundamentally multidisciplinary research around "Memory and trauma" that includes neuroscience, biological and clinical investigations.


Title: Les traces sociales du traumatisme des attentats du 13 novembre 2015 : cinq ans et sept mois après. Abstract: Le suivi de la mémoire des attentats du 13 novembre, et plus généralement des attaques terroristes depuis l'an 2000, auprès de la population générale offre un matériau inédit pour comprendre l'évolution dans le temps et la construction de la mémoire collective. L'étude montre que ces attaques ont davantage marqué la population que d'autres événements tragiques survenus dans l'Hexagone dans une période de temps proche, ou même que d'autres attentats beaucoup plus récents. Avec le temps, la mémorisation précise des faits et les souvenirs des circonstances dans lesquelles les personnes ont appris les faits s'érodent, et se concentrent notamment autour du lieu du Bataclan. Mais, cette imprécision fait place à un investissement symbolique plus fort, qui conduit notamment à une surestimation du nombre de terroristes ou de victimes. Les raisons de la place particulière dévolue aux attaques du 13 novembre dans la mémoire collective tiennent à la fois au nombre inégalé de victimes, à l'attaque de lieux situés dans la capitale, à la réaction des pouvoirs publics qui instaurent l'état d'urgence, au cadrage discursif de la guerre contre le terrorisme amplifié par les médias télévisuels et au sentiment que la menace islamiste peut tuer aveuglément sans viser des catégories précises de population. L'étude met également à jour l'influence des systèmes de valeur (couleur politique, regard sur le modèle républicain) et des caractéristiques sociales des individus sur la mémoire. Elle s'inscrit dans une recherche fondamentalement pluridisciplinaire autour de la « Mémoire et traumatisme ¼ intégrant des travaux en biologie, neurosciences et médecine.


Asunto(s)
Terrorismo , Humanos , Terrorismo/psicología , Francia/epidemiología
15.
Phys Rev Lett ; 130(22): 223402, 2023 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-37327424

RESUMEN

Superradiant lasers operate in the bad-cavity regime, where the phase coherence is stored in the spin state of an atomic medium rather than in the intracavity electric field. Such lasers use collective effects to sustain lasing and could potentially reach considerably lower linewidths than a conventional laser. Here, we investigate the properties of superradiant lasing in an ensemble of ultracold ^{88}Sr atoms inside an optical cavity. We extend the superradiant emission on the 7.5 kHz wide ^{3}P_{1}→^{1}S_{0} intercombination line to several milliseconds, and observe steady parameters suitable for emulating the performance of a continuous superradiant laser by fine tuning the repumping rates. We reach a lasing linewidth of 820 Hz for 1.1 ms of lasing, nearly an order of magnitude lower than the natural linewidth.

16.
Mol Pharmacol ; 104(3): 105-114, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37348913

RESUMEN

The human pituitary adenylate cyclase-activating polypeptide receptor (hPAC1-R), a class B G-protein-coupled receptor (GPCR) identified almost 30 years ago, represents an important pharmacological target in the areas of neuroscience, oncology, and immunology. Despite interest in this target, only a very limited number of small molecule modulators have been reported for this receptor. We herein describe the results of a drug discovery program aiming for the identification of a potent and selective hPAC1-R antagonist. An initial high-throughput screening (HTS) screen of 3.05 million compounds originating from the Bayer screening library failed to identify any tractable hits. A second, completely revised screen using native human embryonic kidney (HEK)293 cells yielded a small number of hits exhibiting antagonistic properties (4.2 million compounds screened). BAY 2686013 (1) emerged as a promising compound showing selective antagonistic activity in the submicromolar potency range. In-depth characterization supported the hypothesis that BAY 2686013 blocks receptor activity in a noncompetitive manner. Preclinical, pharmacokinetic profiling indicates that BAY 2686013 is a valuable tool compound for better understanding the signaling and function of hPAC1-R. SIGNIFICANCE STATEMENT: Although the human pituitary adenylate cyclase-activating polypeptide receptor (hPAC1-R) is of major significance as a therapeutic target with a well documented role in pain signaling, only a very limited number of small-molecule (SMOL) compounds are known to modulate its activity. We identified and thoroughly characterized a novel, potent, and selective SMOL antagonist of hPAC1-R (acting in an allosteric manner). These characteristics make BAY 2686013 an ideal tool for further studies.


Asunto(s)
Polipéptido Hipofisario Activador de la Adenilato-Ciclasa , Receptores del Polipéptido Activador de la Adenilato-Ciclasa Hipofisaria , Humanos , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/farmacología , Receptores del Polipéptido Activador de la Adenilato-Ciclasa Hipofisaria/química
17.
Ecol Lett ; 26(7): 1157-1173, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37156097

RESUMEN

The species-energy hypothesis predicts increasing biodiversity with increasing energy in ecosystems. Proxies for energy availability are often grouped into ambient energy (i.e., solar radiation) and substrate energy (i.e., non-structural carbohydrates or nutritional content). The relative importance of substrate energy is thought to decrease with increasing trophic level from primary consumers to predators, with reciprocal effects of ambient energy. Yet, empirical tests are lacking. We compiled data on 332,557 deadwood-inhabiting beetles of 901 species reared from wood of 49 tree species across Europe. Using host-phylogeny-controlled models, we show that the relative importance of substrate energy versus ambient energy decreases with increasing trophic levels: the diversity of zoophagous and mycetophagous beetles was determined by ambient energy, while non-structural carbohydrate content in woody tissues determined that of xylophagous beetles. Our study thus overall supports the species-energy hypothesis and specifies that the relative importance of ambient temperature increases with increasing trophic level with opposite effects for substrate energy.


Asunto(s)
Escarabajos , Ecosistema , Animales , Árboles , Madera , Biodiversidad , Europa (Continente)
18.
Artículo en Inglés | MEDLINE | ID: mdl-37202183

RESUMEN

BACKGROUND AND OBJECTIVES: Patients with anti-GABA-A receptor encephalitis characteristically experience therapy-refractory epileptic seizures. General anesthesia is often required to terminate refractory status epilepticus. The immunologic mechanisms leading to antibody formation remain to be elucidated. Described triggers of anti-GABA-A autoimmunity are tumors, mainly thymomas, and herpes simplex encephalitis. METHODS: We present a young woman with prediagnosis of relapse remitting multiple sclerosis (MS), treated with interferons, natalizumab, and alemtuzumab. Six months after one and only cycle of alemtuzumab, speech arrest and behavioral changes with aggressive and anxious traits appeared. She showed increasing motor convulsions resulting in focal status epilepticus. RESULTS: Anti-GABA-A receptor antibodies in CSF and serum were confirmed in different external laboratories, in a more extensive analysis after antibodies against NMDAR, CASPR2, LGI1, GABABR, and AMPAR were ruled out during in-house examination. Clinical condition improved temporarily with cortisone therapy, plasmapheresis, and IVIG but deteriorated rapidly after steroid discontinuation, resulting in brain biopsy. On histopathologic confirmation consistent with anti-GABA-A receptor antibody-associated CNS inflammation, completing the first rituximab cycle, continuing oral corticosteroids and supplementing immunosuppression with cyclosporine A led to quick recovery. DISCUSSION: Our case describes a severe autoantibody-induced encephalitis in a young patient with MS, with alemtuzumab as a potential trigger for anti-GABA-A receptor encephalitis.


Asunto(s)
Encefalitis , Epilepsia Parcial Continua , Esclerosis Múltiple , Estado Epiléptico , Femenino , Humanos , Epilepsia Parcial Continua/etiología , Epilepsia Parcial Continua/terapia , Alemtuzumab/efectos adversos , Receptores de GABA-A , Esclerosis Múltiple/complicaciones
19.
Ecol Appl ; 33(6): e2890, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37212374

RESUMEN

Outbreaks of the spongy moth Lymantria dispar can have devastating impacts on forest resources and ecosystems. Lepidoptera-specific insecticides, such as Bacillus thuringiensis var. kurstaki (BTK) and tebufenozide, are often deployed to prevent heavy defoliation of the forest canopy. While it has been suggested that using BTK poses less risk to non-target Lepidoptera than leaving an outbreak untreated, in situ testing of this assumption has been impeded by methodological challenges. The trade-offs between insecticide use and outbreaks have yet to be addressed for tebufenozide, which is believed to have stronger side effects than BTK. We investigated the short-term trade-offs between tebufenozide treatments and no-action strategies for the non-target herbivore community in forest canopies. Over 3 years, Lepidoptera and Symphyta larvae were sampled by canopy fogging in 48 oak stands in southeast Germany during and after a spongy moth outbreak. Half of the sites were treated with tebufenozide and changes in canopy cover were monitored. We contrasted the impacts of tebufenozide and defoliator outbreaks on the abundance, diversity, and functional structure of chewing herbivore communities. Tebufenozide treatments strongly reduced Lepidoptera up to 6 weeks after spraying. Populations gradually converged back to control levels after 2 years. Shelter-building species dominated caterpillar assemblages in treated plots in the post-spray weeks, while flight-dimorphic species were slow to recover and remained underrepresented in treated stands 2 years post-treatment. Spongy moth outbreaks had minor effects on leaf chewer communities. Summer Lepidoptera decreased only when severe defoliation occurred, whereas Symphyta declined 1 year after defoliation. Polyphagous species with only partial host plant overlap with the spongy moth were absent from heavily defoliated sites, suggesting greater sensitivity of generalists to defoliation-induced plant responses. These results demonstrate that both tebufenozide treatments and spongy moth outbreaks alter canopy herbivore communities. Tebufenozide had a stronger and longer lasting impact, but it was restricted to Lepidoptera, whereas the outbreak affected both Lepidoptera and Symphyta. These results are tied to the fact that only half of the outbreak sites experienced severe defoliation. This highlights the limited accuracy of current defoliation forecast methods, which are used as the basis for the decision to spray insecticides.


Asunto(s)
Bacillus thuringiensis , Insecticidas , Mariposas Nocturnas , Animales , Ecosistema
20.
Funct Ecol ; 37(1): 150-161, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37064507

RESUMEN

Climate, topography and the 3D structure of forests are major drivers affecting local species communities. However, little is known about how the specific functional traits of saproxylic (wood-living) beetles, involved in the recycling of wood, might be affected by those environmental characteristics.Here, we combine ecological and morphological traits available for saproxylic beetles and airborne laser scanning (ALS) data in Bayesian trait-based joint species distribution models to study how traits drive the distributions of more than 230 species in temperate forests of Europe.We found that elevation (as a proxy for temperature and precipitation) and the proportion of conifers played important roles in species occurrences while variables related to habitat heterogeneity and forest complexity were less relevant. Furthermore, we showed that local communities were shaped by environmental variation primarily through their ecological traits whereas morphological traits were involved only marginally. As predicted, ecological traits influenced species' responses to forest structure, and to other environmental variation, with canopy niche, wood decay niche and host preference as the most important ecological traits. Conversely, no links between morphological traits and environmental characteristics were observed. Both models, however, revealed strong phylogenetic signal in species' response to environmental characteristics.These findings imply that alterations of climate and tree species composition have the potential to alter saproxylic beetle communities in temperate forests. Additionally, ecological traits help explain species' responses to environmental characteristics and thus should prove useful in predicting their responses to future change. It remains challenging, however, to link simple morphological traits to species' complex ecological niches. Read the free Plain Language Summary for this article on the Journal blog.

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