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1.
Sci Adv ; 10(25): eadp4096, 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38905338

ABSTRACT

The interaction between free electrons and optical fields constitutes a unique platform to investigate ultrafast processes in matter and explore fundamental quantum phenomena. Specifically, optically modulated electrons in ultrafast electron microscopy act as noninvasive probes that push space-time-energy resolution to the picometer-attosecond-microelectronvolt range. Electron energies well above the involved photon energies are commonly used, rendering a low electron-light coupling and, thus, only providing limited access to the wealth of quantum nonlinear phenomena underlying the dynamical response of nanostructures. Here, we theoretically investigate electron-light interactions between photons and electrons of comparable energies, revealing quantum and recoil effects that include a nonvanishing coupling of surface-scattered electrons to light plane waves, inelastic electron backscattering from confined optical fields, and strong electron-light coupling under grazing electron diffraction by an illuminated crystal surface. Our exploration of electron-light-matter interactions holds potential for applications in ultrafast electron microscopy.

2.
Domest Anim Endocrinol ; 88: 106854, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38733943

ABSTRACT

This study evaluated the efficiency of prostaglandin F2α (PGF) to hasten ovulation in weaned sows. In experiment I, weaned sows detected in estrus (0 h) received: no hormone (Control; n = 56); 0.5 mg PGF IM at 0 h and 2 h (PGF0; n = 56); or 0.5 mg PGF IM at 24 h and 26 h (PGF24; n = 55). In experiment II, weaned sows that did not express estrus signs until 72 h after weaning (0 h) were assigned to: no hormone (Control; n = 45); 10 µg buserelin acetate IM at 0 h (Buserelin; n = 43); 0.5 mg PGF IM at 34 h and 36 h (PGF; n = 44); or 10 µg buserelin acetate IM at 0 h plus 0.5 mg PGF IM at 34 h and 36 h (Buserelin + PGF; n = 45). In experiment I, no effect of PGF on the interval treatment onset to ovulation was observed (P > 0.05), and no treatment effect was observed on the relative or cumulative proportion of females that ovulated post-treatment onset (P > 0.05). In experiment II, treatment onset to ovulation interval was shorter for Buserelin group than for PGF group (P < 0.05), and a higher cumulative percentage of Buserelin treated sows ovulated up to 48 h compared to PGF and Control groups (P < 0.01), with no differences from Buserelin + PGF. Treatments did not affect total number of piglets born in both experiments (P > 0.05). In conclusion, PGF did not hasten ovulation timing or affect litter size in weaned sows.


Subject(s)
Buserelin , Dinoprost , Ovulation , Animals , Female , Dinoprost/pharmacology , Dinoprost/administration & dosage , Swine/physiology , Ovulation/drug effects , Ovulation/physiology , Buserelin/pharmacology , Buserelin/administration & dosage , Weaning , Ovulation Induction/veterinary , Ovulation Induction/methods
3.
Braz J Biol ; 83: e276465, 2024.
Article in English | MEDLINE | ID: mdl-38422266

ABSTRACT

The zebrafish has been used in research for over 80 years. In the last three decades, discoveries about the fundamental properties of development, regeneration, cancer, and other diseases have established the zebrafish as an important model organism in biomedical research. This study aimed to evaluate liver alterations in zebrafish by quantitatively assessing the areas occupied by hepatocytes, as well as connective and adipose tissues. Forty-eight adult Danio rerio (38 males and 10 females) of approximately 13 months of age were used. They were divided into four groups, with 12 animals each. The fish were randomly distributed to form the groups, which received a maintenance and/or hypercaloric diet, with or without the addition of physical exercise. The animals underwent six hours of forced exercise (5 cm/s) for thirteen weeks. The animals that practiced physical exercise had a higher volumetric density of the area occupied by hepatocytes (65.92%±1.81 - GMex and 50.75%±2.24 GHex) among the groups. The GH group had a higher volumetric density of the area occupied by connective tissue (15.12%±0.72), followed by the GHex group (13.53%±1.43). Regarding the volumetric density of the area occupied by adipose tissue, the GH group had a higher density (27.21%±1.36), followed by the GHex group (21.66%±1.11) with statistically significant differences. The GMex had a volumetric density of the area occupied by adipose tissue of 3.5%±0.76, while the GM had 5.7%±0.5, with statistical difference. In relation to the animals in the GHex group, they had 20.39% less fat than the animals in the GH group. The animals in the GMex group had 72.47% less fat than those in the GM group. It is concluded that the different dietary constitutions and the imposition of physical exercise were able to modify the structural architecture of the liver of Danio rerio. These are acceptable criteria for modulations, thus aiming at the control and possible interferences directly related to the metabolism of the species and therefore the control of diseases.


Subject(s)
Perciformes , Zebrafish , Animals , Female , Male , Liver , Diet , Adipose Tissue
4.
Ann Oncol ; 35(2): 221-228, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38072158

ABSTRACT

BACKGROUND: Metastatic basal cell carcinoma (mBCC) is a rare condition with no effective second-line treatment options. Cemiplimab is an immune checkpoint inhibitor that blocks the binding of programmed cell death-1 (PD-1) to its ligands, programmed death-ligand 1 (PD-L1) and programmed death-ligand 2 (PD-L2). Here, we present the final analysis of cemiplimab in patients with mBCC after first-line hedgehog pathway inhibitor (HHI) treatment (NCT03132636). PATIENTS AND METHODS: In this open-label, single-arm, phase II study, adults with mBCC and Eastern Cooperative Oncology Group performance status ≤1, post-HHI treatment, received cemiplimab 350 mg intravenously every 3 weeks for ≤93 weeks or until disease progression or unacceptable toxicity. The primary endpoint was objective response rate (ORR) by independent central review (ICR). Duration of response (DOR) was a key secondary endpoint. Other secondary endpoints were ORR per investigator assessment, progression-free survival (PFS), overall survival (OS), complete response rate, safety, and tolerability. RESULTS: Fifty-four patients were enrolled: 70% were male and the median age of patients was 64 [interquartile range (IQR) 57.0-73.0] years. The median duration of follow-up was 8 months (IQR 4-21 months). The ORR per ICR was 22% [95% confidence interval (CI) 12% to 36%], with 2 complete responses and 10 partial responses. Among responders, the median time to response per ICR was 3 months (IQR 2-7 months). The estimated median DOR per ICR was not reached [95% CI 10 months-not evaluable (NE)]. The disease control rate was 63% (95% CI 49% to 76%) per ICR and 70% (95% CI 56% to 82%) per investigator assessment. The median PFS per ICR was 10 months (95% CI 4-16 months); the median OS was 50 months (95% CI 28 months-NE). The most common treatment-emergent adverse events were fatigue [23 (43%)] and diarrhoea [20 (37%)]. There were no treatment-related deaths. CONCLUSIONS: Cemiplimab demonstrated clinically meaningful antitumour activity, including durable responses, and an acceptable safety profile in patients with mBCC who had disease progression on or intolerance to HHI therapy.


Subject(s)
Antibodies, Monoclonal, Humanized , Antineoplastic Agents , Carcinoma, Basal Cell , Skin Neoplasms , Adult , Humans , Male , Middle Aged , Aged , Female , Hedgehog Proteins , Ligands , Antineoplastic Agents/therapeutic use , Carcinoma, Basal Cell/drug therapy , Carcinoma, Basal Cell/chemically induced , Disease Progression , Amides/therapeutic use , Skin Neoplasms/drug therapy , Skin Neoplasms/pathology
5.
Int J Risk Saf Med ; 35(1): 19-24, 2024.
Article in English | MEDLINE | ID: mdl-37718852

ABSTRACT

BACKGROUND: Medication reconciliation is advocated to ensure the continuity, safety, and effective use of medicines across transitions of care. CASE REPORT: In this report, we describe the case of a 90-year-old female with previous diagnoses of atrial fibrillation and cutaneous metastatic breast cancer presenting with bilateral ulcerative lesions on the chest wall. The patient was diagnosed with Deep Vein Thrombosis at the Emergency Department and started on rivaroxaban, although the patient was already taking edoxaban. This therapeutic duplication was noticed only one week later, even though she was already experiencing significant bleeding managed through a prescribing cascade. Despite the technical error (action-based), it is possible to identify several weaknesses in the organisation's structure, which provided a trajectory of accident opportunity. CONCLUSION: Anticoagulants are ranked first for the highest priority to receive a medication reconciliation. To achieve an optimal level of medication reconciliation, we ought to recognise and correct latent failures.


Subject(s)
Atrial Fibrillation , Breast Neoplasms , Skin Neoplasms , Thoracic Wall , Female , Humans , Aged, 80 and over , Medication Reconciliation , Anticoagulants , Atrial Fibrillation/drug therapy , Breast Neoplasms/drug therapy
6.
Nanoscale ; 15(28): 11852-11859, 2023 Jul 20.
Article in English | MEDLINE | ID: mdl-37401202

ABSTRACT

Plasmons can be excited during photoemission and produce spectral photoelectron features that yield information on the nanoscale optical response of the probed materials. However, these so-called plasmon satellites have so far been observed only for planar surfaces, while their potential for the characterization of nanostructures remains unexplored. Here, we theoretically demonstrate that core-level photoemission from nanostructures can display spectrally narrow plasmonic features, reaching relatively high probabilities similar to the direct peak. Using a nonperturbative quantum-mechanical framework, we find a dramatic effect of nanostructure morphology and dimensionality as well as universal scaling laws for the plasmon-satellite probabilities. In addition, we introduce a pump-probe scheme in which plasmons are optically excited prior to photoemission, leading to plasmon losses and gains in the photoemission spectra and granting us access to the ultrafast dynamics of the sampled nanostructure. These results emphasize the potential of plasmon satellites to explore multi-plasmon effects and ultrafast electron-plasmon dynamics in metal-based nanoparticles and two-dimensional nanoislands.

7.
Neurochirurgie ; 69(5): 101472, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37482184

ABSTRACT

Juvenile xanthogranuloma (JXG) is a rare type of non-Langerhans cell histiocytosis. Its systemic form affects 4% of patients. Lesions in the Central Nervous System (CNS) occur in 2% of systemic cases. Sellar JXG should be one of the differential diagnoses for sellar lesions in young. This is a 15-year-old patient with non-specific headache, progressive visual loss and magnetic resonance imaging showing sellar lesion with suprasellar extension. The patient underwent microsurgery by pterional craniotomy with partial resection of the tumor. Pathology evidenced JXG. It progressively evolved with impairment of neuroendocrine functions, new lesions in different CNS locations and death two years after diagnosis. Sellar JXG without cutaneous manifestations is rare. There are no specific findings of the disease. Diagnosis requires additional tests, being defined by pathological analysis. Total resection presents a greater potential control comparing to partial resection. Even so, some patients may have progressive disease with poor clinical outcome.


Subject(s)
Xanthogranuloma, Juvenile , Adolescent , Humans , Diagnosis, Differential , Headache , Magnetic Resonance Imaging , Xanthogranuloma, Juvenile/diagnosis , Xanthogranuloma, Juvenile/surgery , Xanthogranuloma, Juvenile/pathology
8.
Nano Lett ; 23(10): 4242-4249, 2023 May 24.
Article in English | MEDLINE | ID: mdl-37172322

ABSTRACT

A rigorous account of quantum nonlocal effects is paramount for understanding the optical response of metal nanostructures and for designing plasmonic devices at the nanoscale. Here, we present a scheme for retrieving the quantum surface response of metals, encapsulated in the Feibelman d-parameters, from electron energy-loss spectroscopy (EELS) and cathodoluminescence (CL) measurements. We theoretically demonstrate that quantum nonlocal effects have a dramatic impact on EELS and CL spectra, in the guise of spectral shifts and nonlocal damping, when either the system size or the inverse wave vector in extended structures approaches the nanometer scale. Our concept capitalizes on the unparalleled ability of free electrons to supply deeply subwavelength near-fields and, thus, probe the optical response of metals at length scales in which quantum-mechanical effects are apparent. These results pave the way for a widespread use of the d-parameter formalism, thereby facilitating a rigorous yet practical inclusion of nonclassical effects in nanoplasmonics.

9.
Plant Biol (Stuttg) ; 25(1): 208-214, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36184888

ABSTRACT

Galls display a multiplicity of traits, including colours, which are driven by pigment accumulation. Their conspicuousness has attracted researchers' attention and several hypotheses have been raised. However, plants themselves vary intra-specifically, including in their pigment concentrations. As galls are a result of host tissue development, colours may be a by-product of the host's own traits, being more conspicuous simply because the sites where galls develop already have the predisposition to accumulate more pigment. Here, we call this the host variation hypothesis. We test this hypothesis using the system of galls induced by Palaeomystella oligophaga on Macairea radula host plant. Using spectrophotometry, we calculated the Anthocyanin Reflectance Index (ARI) of gall projections, which are responsible for their characteristic colours. We tested the influence of occupant identity (galling insect or any natural enemy), gall volume, parenchyma thickness, height from the ground, ARI of leaf, ARI of gall surface and ARI of the respective stem. We corroborated the host variation hypothesis since the anthocyanin content in stems and in galls' projections were positively related. Moreover, anthocyanin in galls' projections was positively related to anthocyanin in the gall surface and negatively related to gall volume and parenchyma thickness. This shows that, besides the host specificities, galls' own traits may also be responsible for pigment accumulation, influencing their colours. In this study, using colour as an example, we show that although galls tend to be considered complex expressions of galling insects' stimuli, their traits may be simply influenced by previous and specific attributes of the host organs.


Subject(s)
Melastomataceae , Moths , Animals , Plant Tumors , Anthocyanins , Plants , Insecta , Host-Parasite Interactions
10.
Stud Mycol ; 105: 1-22, 2023 Jun.
Article in English | MEDLINE | ID: mdl-38895705

ABSTRACT

The subphylum Saccharomycotina is a lineage in the fungal phylum Ascomycota that exhibits levels of genomic diversity similar to those of plants and animals. The Saccharomycotina consist of more than 1 200 known species currently divided into 16 families, one order, and one class. Species in this subphylum are ecologically and metabolically diverse and include important opportunistic human pathogens, as well as species important in biotechnological applications. Many traits of biotechnological interest are found in closely related species and often restricted to single phylogenetic clades. However, the biotechnological potential of most yeast species remains unexplored. Although the subphylum Saccharomycotina has much higher rates of genome sequence evolution than its sister subphylum, Pezizomycotina, it contains only one class compared to the 16 classes in Pezizomycotina. The third subphylum of Ascomycota, the Taphrinomycotina, consists of six classes and has approximately 10 times fewer species than the Saccharomycotina. These data indicate that the current classification of all these yeasts into a single class and a single order is an underappreciation of their diversity. Our previous genome-scale phylogenetic analyses showed that the Saccharomycotina contains 12 major and robustly supported phylogenetic clades; seven of these are current families (Lipomycetaceae, Trigonopsidaceae, Alloascoideaceae, Pichiaceae, Phaffomycetaceae, Saccharomycodaceae, and Saccharomycetaceae), one comprises two current families (Dipodascaceae and Trichomonascaceae), one represents the genus Sporopachydermia, and three represent lineages that differ in their translation of the CUG codon (CUG-Ala, CUG-Ser1, and CUG-Ser2). Using these analyses in combination with relative evolutionary divergence and genome content analyses, we propose an updated classification for the Saccharomycotina, including seven classes and 12 orders that can be diagnosed by genome content. This updated classification is consistent with the high levels of genomic diversity within this subphylum and is necessary to make the higher rank classification of the Saccharomycotina more comparable to that of other fungi, as well as to communicate efficiently on lineages that are not yet formally named. Taxonomic novelties: New classes: Alloascoideomycetes M. Groenew., Hittinger, Opulente & A. Rokas, Dipodascomycetes M. Groenew., Hittinger, Opulente & A. Rokas, Lipomycetes M. Groenew., Hittinger, Opulente, A. Rokas, Pichiomycetes M. Groenew., Hittinger, Opulente & A. Rokas, Sporopachydermiomycetes M. Groenew., Hittinger, Opulente & A. Rokas, Trigonopsidomycetes M. Groenew., Hittinger, Opulente & A. Rokas. New orders: Alloascoideomycetes: Alloascoideales M. Groenew., Hittinger, Opulente & A. Rokas; Dipodascomycetes: Dipodascales M. Groenew., Hittinger, Opulente & A. Rokas; Lipomycetes: Lipomycetales M. Groenew., Hittinger, Opulente & A. Rokas; Pichiomycetes: Alaninales M. Groenew., Hittinger, Opulente & A. Rokas, Pichiales M. Groenew., Hittinger, Opulente & A. Rokas, Serinales M. Groenew., Hittinger, Opulente & A. Rokas; Saccharomycetes: Phaffomycetales M. Groenew., Hittinger, Opulente & A. Rokas, Saccharomycodales M. Groenew., Hittinger, Opulente & A. Rokas; Sporopachydermiomycetes: Sporopachydermiales M. Groenew., Hittinger, Opulente & A. Rokas; Trigonopsidomycetes: Trigonopsidales M. Groenew., Hittinger, Opulente & A. Rokas. New families: Alaninales: Pachysolenaceae M. Groenew., Hittinger, Opulente & A. Rokas; Pichiales: Pichiaceae M. Groenew., Hittinger, Opulente & A. Rokas; Sporopachydermiales: Sporopachydermiaceae M. Groenew., Hittinger, Opulente & A. Rokas. Citation: Groenewald M, Hittinger CT, Bensch K, Opulente DA, Shen X-X, Li Y, Liu C, LaBella AL, Zhou X, Limtong S, Jindamorakot S, Gonçalves P, Robert V, Wolfe KH, Rosa CA, Boekhout T, Cadez N, Péter G, Sampaio JP, Lachance M-A, Yurkov AM, Daniel H-M, Takashima M, Boundy-Mills K, Libkind D, Aoki K, Sugita T, Rokas A (2023). A genome-informed higher rank classification of the biotechnologically important fungal subphylum Saccharomycotina. Studies in Mycology 105: 1-22. doi: 10.3114/sim.2023.105.01 This study is dedicated to the memory of Cletus P. Kurtzman (1938-2017), a pioneer of yeast taxonomy.

11.
Braz. j. biol ; 83: 1-5, 2023. tab, ilus
Article in English | LILACS, VETINDEX | ID: biblio-1468968

ABSTRACT

Plant-derived products can assist in the healing process of dermal wounds. It has been demonstrated that Hancornia speciosa latex present angiogenic, osteogenic, anti-inflammatory, and antioxidant activities. Then, it could contribute to the wound healing process. However, natural products in contact with skin may cause dermatitis. The objective of this work was to evaluate the allergic and irritant potential of H. speciosa serum fraction latex using in vitro assays. The obtained results showed that the H. speciosa serum fraction latex has a slightly irritant potential and is not cytotoxic neither allergenic for human cells. Moreover, we identified a remarkable low amount of proteins in this material in comparison to Hevea brasiliensis latex. This result could explain the non-allergenic potential of H. speciosa serum fraction latex because proteins present in latex are the main responsible for allergy. This biomaterial could be used as a non-allergenic source for development of new medicines.


Produtos derivados de plantas podem auxiliar no processo de cicatrização de feridas cutâneas. Foi demonstrado que o látex de Hancornia speciosa apresenta atividades angiogênicas, osteogênicas, antiinflamatórias e antioxidantes. Então, este biomaterial pode contribuir para o processo de cicatrização de feridas. No entanto, produtos naturais em contato com a pele podem causar dermatites. O objetivo deste trabalho foi avaliar o potencial alérgico e irritante do látex da fração soro de H. speciosa por meio de ensaios in vitro. Os resultados obtidos mostraram que o látex da fração do soro de H. speciosa possui um potencial pouco irritante e não é citotóxico nem alergênico para células humanas. Além disso, foi identificado uma notável baixa quantidade de proteínas neste material em comparação ao látex de Hevea brasiliensis. Esse resultado poderia explicar o potencial não alergênico do látex da fração soro de H. speciosa, pois as proteínas presentes no látex são as principais responsáveis pela alergia. Este biomaterial pode ser utilizado como fonte não alergênica para desenvolvimento de novos medicamentos.


Subject(s)
Apocynaceae/chemistry , Wound Healing/drug effects , In Vitro Techniques
12.
Braz. j. biol ; 832023.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469184

ABSTRACT

Abstract Plant-derived products can assist in the healing process of dermal wounds. It has been demonstrated that Hancornia speciosa latex present angiogenic, osteogenic, anti-inflammatory, and antioxidant activities. Then, it could contribute to the wound healing process. However, natural products in contact with skin may cause dermatitis. The objective of this work was to evaluate the allergic and irritant potential of H. speciosa serum fraction latex using in vitro assays. The obtained results showed that the H. speciosa serum fraction latex has a slightly irritant potential and is not cytotoxic neither allergenic for human cells. Moreover, we identified a remarkable low amount of proteins in this material in comparison to Hevea brasiliensis latex. This result could explain the non-allergenic potential of H. speciosa serum fraction latex because proteins present in latex are the main responsible for allergy. This biomaterial could be used as a non-allergenic source for development of new medicines.


Resumo Produtos derivados de plantas podem auxiliar no processo de cicatrização de feridas cutâneas. Foi demonstrado que o látex de Hancornia speciosa apresenta atividades angiogênicas, osteogênicas, antiinflamatórias e antioxidantes. Então, este biomaterial pode contribuir para o processo de cicatrização de feridas. No entanto, produtos naturais em contato com a pele podem causar dermatites. O objetivo deste trabalho foi avaliar o potencial alérgico e irritante do látex da fração soro de H. speciosa por meio de ensaios in vitro. Os resultados obtidos mostraram que o látex da fração do soro de H. speciosa possui um potencial pouco irritante e não é citotóxico nem alergênico para células humanas. Além disso, foi identificado uma notável baixa quantidade de proteínas neste material em comparação ao látex de Hevea brasiliensis. Esse resultado poderia explicar o potencial não alergênico do látex da fração soro de H. speciosa, pois as proteínas presentes no látex são as principais responsáveis pela alergia. Este biomaterial pode ser utilizado como fonte não alergênica para desenvolvimento de novos medicamentos.

13.
Braz. j. biol ; 83: e251075, 2023. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1339401

ABSTRACT

Abstract Plant-derived products can assist in the healing process of dermal wounds. It has been demonstrated that Hancornia speciosa latex present angiogenic, osteogenic, anti-inflammatory, and antioxidant activities. Then, it could contribute to the wound healing process. However, natural products in contact with skin may cause dermatitis. The objective of this work was to evaluate the allergic and irritant potential of H. speciosa serum fraction latex using in vitro assays. The obtained results showed that the H. speciosa serum fraction latex has a slightly irritant potential and is not cytotoxic neither allergenic for human cells. Moreover, we identified a remarkable low amount of proteins in this material in comparison to Hevea brasiliensis latex. This result could explain the non-allergenic potential of H. speciosa serum fraction latex because proteins present in latex are the main responsible for allergy. This biomaterial could be used as a non-allergenic source for development of new medicines.


Resumo Produtos derivados de plantas podem auxiliar no processo de cicatrização de feridas cutâneas. Foi demonstrado que o látex de Hancornia speciosa apresenta atividades angiogênicas, osteogênicas, antiinflamatórias e antioxidantes. Então, este biomaterial pode contribuir para o processo de cicatrização de feridas. No entanto, produtos naturais em contato com a pele podem causar dermatites. O objetivo deste trabalho foi avaliar o potencial alérgico e irritante do látex da fração soro de H. speciosa por meio de ensaios in vitro. Os resultados obtidos mostraram que o látex da fração do soro de H. speciosa possui um potencial pouco irritante e não é citotóxico nem alergênico para células humanas. Além disso, foi identificado uma notável baixa quantidade de proteínas neste material em comparação ao látex de Hevea brasiliensis. Esse resultado poderia explicar o potencial não alergênico do látex da fração soro de H. speciosa, pois as proteínas presentes no látex são as principais responsáveis ​​pela alergia. Este biomaterial pode ser utilizado como fonte não alergênica para desenvolvimento de novos medicamentos.


Subject(s)
Humans , Apocynaceae , Hevea , Wound Healing , Biocompatible Materials , Allergens , Latex
14.
Nat Commun ; 13(1): 5175, 2022 Sep 02.
Article in English | MEDLINE | ID: mdl-36056011

ABSTRACT

Tuning electrical, optical, and thermal material properties is central for engineering and understanding solid-state systems. In this scenario, atomically thin materials are appealing because of their sensitivity to electric and magnetic gating, as well as to interlayer hybridization. Here, we introduce a radically different approach to material engineering relying on the image interaction experienced by electrons in a two-dimensional material when placed in proximity of an electrically neutral structure. We theoretically show that electrons in a semiconductor atomic layer acquire a quantum phase resulting from the image potential induced by the presence of a neighboring periodic array of conducting ribbons, which in turn modifies the optical, electrical, and thermal properties of the monolayer, giving rise to additional interband optical absorption, plasmon hybridization, and metal-insulator transitions. Beyond its fundamental interest, material engineering based on the image interaction represents a disruptive approach to tailor the properties of atomic layers for application in nanodevices.

15.
Nat Commun ; 13(1): 3105, 2022 Jun 03.
Article in English | MEDLINE | ID: mdl-35661728

ABSTRACT

Historically, the field of plasmonics has been relying on the framework of classical electrodynamics, with the local-response approximation of material response being applied even when dealing with nanoscale metallic structures. However, when the confinement of electromagnetic radiation approaches atomic scales, mesoscopic effects are anticipated to become observable, e.g., those associated with the nonlocal electrodynamic surface response of the electron gas. Here, we investigate nonlocal effects in propagating gap surface plasmon modes in ultrathin metal-dielectric-metal planar waveguides, exploiting monocrystalline gold flakes separated by atomic-layer-deposited aluminum oxide. We use scanning near-field optical microscopy to directly access the near-field of such confined gap plasmon modes and measure their dispersion relation via their complex-valued propagation constants. We compare our experimental findings with the predictions of the generalized nonlocal optical response theory to unveil signatures of nonlocal damping, which becomes appreciable for few-nanometer-sized dielectric gaps.

16.
Braz. j. biol ; 82: 1-7, 2022. ilus, tab
Article in English | LILACS, VETINDEX | ID: biblio-1468448

ABSTRACT

Several studies emphasize the use of owl pellets in small mammal inventories in natural areas harboring high richness of rare species, but few Brazilian Atlantic forest localities have been surveyed by this method. The present study documents the species composition and abundance of small mammals in the diet of Tyto furcata in an urban area of the municipality of Campos dos Goytacazes, Rio de Janeiro, Brazil, remarking on a new record of the dwarf mouse opossum genus Cryptonanus in the Atlantic forest. We analyzed 265 pellets regurgitated by a pair of T. furcata from November 2016 to September 2017 found in a nesting box. Analysis of the samples enabled finding a total of 596 individuals of four small mammal species. Mus musculus was predominant among the prey items (98.3%), while the native rodents Necromys lasiurus (1.3%) and Holochilus brasiliensis (0,17%) were much rarer. A single specimen of Cryptonanus sp. was identified among the diet items based on distinctive dental characters. The identification of this genus in the present study represents the second record in the state of Rio de Janeiro, and the sixth in the Atlantic Forest biome, suggesting that this marsupial occupies a wider ecological and biogeographic range. The present study underscores the relevance of owl pellets for small mammal surveys, even in urban and highly disturbed areas.


Vários estudos enfatizam o uso de pelotas de coruja em inventários de pequenos mamíferos em áreas naturais com elevada riqueza de espécies raras, mas poucas localidades da Mata Atlântica brasileira têm sido inventariadas por esse método. O presente estudo documenta a composição de espécies e abundância de pequenos mamíferos na dieta de Tyto furcata em uma área urbana do município de Campos dos Goytacazes, Rio de Janeiro, Brasil, discutindo a relevância de um novo registro de um raro marsupial do gênero Cryptonanus na Mata Atlântica. Foram analisadas 265 pelotas regurgitadas por um casal de T. furcata entre novembro de 2016 e setembro de 2017, encontradas abaixo de uma caixa de nidificação. A análise das amostras permitiu encontrar o total de 596 indivíduos de quatro espécies pequenas de mamíferos. O roedor exótico Mus musculus foi predominante entre os itens alimentares (98,3%), enquanto os roedores nativos Necromys lasiurus (1,3%) e Holochilus brasiliensis (0,17%) foram bem mais raros. Um único espécime de Cryptonanus sp. foi identificado entre os itens com base em caracteres dentários. A identificação desse gênero no presente estudo representa o segundo registro no estado do Rio de Janeiro e o sexto no bioma Mata Atlântica, sugerindo que este marsupial ocupa uma ampla faixa ecológica e biogeográfica. O presente estudo destaca a relevância dos pellets de coruja para pesquisas com pequenos mamíferos, mesmo em áreas urbanas e altamente perturbadas.


Subject(s)
Animals , Diet/veterinary , Strigiformes , Marsupialia , Gastroesophageal Reflux/veterinary , Mice
17.
Braz. j. biol ; 822022.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468635

ABSTRACT

Abstract Several studies emphasize the use of owl pellets in small mammal inventories in natural areas harboring high richness of rare species, but few Brazilian Atlantic forest localities have been surveyed by this method. The present study documents the species composition and abundance of small mammals in the diet of Tyto furcata in an urban area of the municipality of Campos dos Goytacazes, Rio de Janeiro, Brazil, remarking on a new record of the dwarf mouse opossum genus Cryptonanus in the Atlantic forest. We analyzed 265 pellets regurgitated by a pair of T. furcata from November 2016 to September 2017 found in a nesting box. Analysis of the samples enabled finding a total of 596 individuals of four small mammal species. Mus musculus was predominant among the prey items (98.3%), while the native rodents Necromys lasiurus (1.3%) and Holochilus brasiliensis (0,17%) were much rarer. A single specimen of Cryptonanus sp. was identified among the diet items based on distinctive dental characters. The identification of this genus in the present study represents the second record in the state of Rio de Janeiro, and the sixth in the Atlantic Forest biome, suggesting that this marsupial occupies a wider ecological and biogeographic range. The present study underscores the relevance of owl pellets for small mammal surveys, even in urban and highly disturbed areas.


Resumo Vários estudos enfatizam o uso de pelotas de coruja em inventários de pequenos mamíferos em áreas naturais com elevada riqueza de espécies raras, mas poucas localidades da Mata Atlântica brasileira têm sido inventariadas por esse método. O presente estudo documenta a composição de espécies e abundância de pequenos mamíferos na dieta de Tyto furcata em uma área urbana do município de Campos dos Goytacazes, Rio de Janeiro, Brasil, discutindo a relevância de um novo registro de um raro marsupial do gênero Cryptonanus na Mata Atlântica. Foram analisadas 265 pelotas regurgitadas por um casal de T. furcata entre novembro de 2016 e setembro de 2017, encontradas abaixo de uma caixa de nidificação. A análise das amostras permitiu encontrar o total de 596 indivíduos de quatro espécies pequenas de mamíferos. O roedor exótico Mus musculus foi predominante entre os itens alimentares (98,3%), enquanto os roedores nativos Necromys lasiurus (1,3%) e Holochilus brasiliensis (0,17%) foram bem mais raros. Um único espécime de Cryptonanus sp. foi identificado entre os itens com base em caracteres dentários. A identificação desse gênero no presente estudo representa o segundo registro no estado do Rio de Janeiro e o sexto no bioma Mata Atlântica, sugerindo que este marsupial ocupa uma ampla faixa ecológica e biogeográfica. O presente estudo destaca a relevância dos pellets de coruja para pesquisas com pequenos mamíferos, mesmo em áreas urbanas e altamente perturbadas.

18.
Braz. j. biol ; 82: e237675, 2022. tab, mapas, ilus
Article in English | LILACS, VETINDEX | ID: biblio-1249234

ABSTRACT

Several studies emphasize the use of owl pellets in small mammal inventories in natural areas harboring high richness of rare species, but few Brazilian Atlantic forest localities have been surveyed by this method. The present study documents the species composition and abundance of small mammals in the diet of Tyto furcata in an urban area of the municipality of Campos dos Goytacazes, Rio de Janeiro, Brazil, remarking on a new record of the dwarf mouse opossum genus Cryptonanus in the Atlantic forest. We analyzed 265 pellets regurgitated by a pair of T. furcata from November 2016 to September 2017 found in a nesting box. Analysis of the samples enabled finding a total of 596 individuals of four small mammal species. Mus musculus was predominant among the prey items (98.3%), while the native rodents Necromys lasiurus (1.3%) and Holochilus brasiliensis (0,17%) were much rarer. A single specimen of Cryptonanus sp. was identified among the diet items based on distinctive dental characters. The identification of this genus in the present study represents the second record in the state of Rio de Janeiro, and the sixth in the Atlantic Forest biome, suggesting that this marsupial occupies a wider ecological and biogeographic range. The present study underscores the relevance of owl pellets for small mammal surveys, even in urban and highly disturbed areas.


Vários estudos enfatizam o uso de pelotas de coruja em inventários de pequenos mamíferos em áreas naturais com elevada riqueza de espécies raras, mas poucas localidades da Mata Atlântica brasileira têm sido inventariadas por esse método. O presente estudo documenta a composição de espécies e abundância de pequenos mamíferos na dieta de Tyto furcata em uma área urbana do município de Campos dos Goytacazes, Rio de Janeiro, Brasil, discutindo a relevância de um novo registro de um raro marsupial do gênero Cryptonanus na Mata Atlântica. Foram analisadas 265 pelotas regurgitadas por um casal de T. furcata entre novembro de 2016 e setembro de 2017, encontradas abaixo de uma caixa de nidificação. A análise das amostras permitiu encontrar o total de 596 indivíduos de quatro espécies pequenas de mamíferos. O roedor exótico Mus musculus foi predominante entre os itens alimentares (98,3%), enquanto os roedores nativos Necromys lasiurus (1,3%) e Holochilus brasiliensis (0,17%) foram bem mais raros. Um único espécime de Cryptonanus sp. foi identificado entre os itens com base em caracteres dentários. A identificação desse gênero no presente estudo representa o segundo registro no estado do Rio de Janeiro e o sexto no bioma Mata Atlântica, sugerindo que este marsupial ocupa uma ampla faixa ecológica e biogeográfica. O presente estudo destaca a relevância dos pellets de coruja para pesquisas com pequenos mamíferos, mesmo em áreas urbanas e altamente perturbadas.


Subject(s)
Animals , Urban Area , Strigiformes , Diet , Marsupialia , Brazil
19.
Braz J Biol ; 83: e251075, 2021.
Article in English | MEDLINE | ID: mdl-34669807

ABSTRACT

Plant-derived products can assist in the healing process of dermal wounds. It has been demonstrated that Hancornia speciosa latex present angiogenic, osteogenic, anti-inflammatory, and antioxidant activities. Then, it could contribute to the wound healing process. However, natural products in contact with skin may cause dermatitis. The objective of this work was to evaluate the allergic and irritant potential of H. speciosa serum fraction latex using in vitro assays. The obtained results showed that the H. speciosa serum fraction latex has a slightly irritant potential and is not cytotoxic neither allergenic for human cells. Moreover, we identified a remarkable low amount of proteins in this material in comparison to Hevea brasiliensis latex. This result could explain the non-allergenic potential of H. speciosa serum fraction latex because proteins present in latex are the main responsible for allergy. This biomaterial could be used as a non-allergenic source for development of new medicines.


Subject(s)
Apocynaceae , Hevea , Allergens , Biocompatible Materials , Humans , Latex , Wound Healing
20.
Sci Rep ; 11(1): 14029, 2021 07 07.
Article in English | MEDLINE | ID: mdl-34234237

ABSTRACT

Toxoplasma gondii is an opportunistic protozoan pathogen with a wide geographic distribution. The chronic phase of toxoplasmosis is often asymptomatic in humans and is characterized by tissue cysts throughout the central nervous system and muscle cells. T. gondii and other pathogens with tropism for the central nervous system are considered risk factors in the etiology of several neuropsychiatric disorders, such as schizophrenia and bipolar disorder, besides neurological diseases. Currently, it is known that cerebral toxoplasmosis increases dopamine levels in the brain and it is related to behavioral changes in animals and humans. Here we evaluate whether chronic T. gondii infection, using the cystogenic ME-49 strain, could induce behavioral alterations associated with neuropsychiatric disorders and glutamatergic neurotransmission dysfunction. We observed that the startle amplitude is reduced in the infected animals as well as glutamate and D-serine levels in prefrontal cortical and hippocampal tissue homogenates. Moreover, we did not detect alterations in social preference and spontaneous alternation despite severe motor impairment. Thus, we conclude that behavioral and cognitive aspects are maintained even though severe neural damage is observed by chronic infection of C57Bl/6 mice with the ME-49 strain.


Subject(s)
Glutamic Acid/metabolism , Mental Disorders/etiology , Mental Disorders/metabolism , Reflex, Startle , Serine/metabolism , Toxoplasmosis, Cerebral/complications , Toxoplasmosis, Cerebral/parasitology , Animals , Behavior, Animal , Body Weight , Brain/metabolism , Brain/parasitology , Brain/pathology , Hippocampus/metabolism , Mental Disorders/diagnosis , Mental Disorders/psychology , Mice , Neurotransmitter Agents/metabolism , Prefrontal Cortex/metabolism , Social Behavior , Toxoplasma
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