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1.
J Neurosci ; 44(10)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38326038

RESUMO

There has been considerable controversy about pre- versus postsynaptic expression of memory-related long-term potentiation (LTP), with corresponding disputes about underlying mechanisms. We report here an instance in male mice, in which both types of potentiation are expressed but in separate branches of the same hippocampal afferent. Induction of LTP in the dentate gyrus (DG) branch of the lateral perforant path (LPP) reduces paired-pulse facilitation, is blocked by antagonism of cannabinoid receptor type 1, and is not affected by suppression of postsynaptic actin polymerization. These observations are consistent with presynaptic expression. The opposite pattern of results was obtained in the LPP branch that innervates the distal dendrites of CA3: LTP did not reduce paired-pulse facilitation, was unaffected by the cannabinoid receptor blocker, and required postsynaptic actin filament assembly. Differences in the two LPP termination sites were also noted for frequency facilitation of synaptic responses, an effect that was reproduced in a two-step simulation by small adjustments to vesicle release dynamics. These results indicate that different types of glutamatergic neurons impose different forms of filtering and synaptic plasticity on their afferents. They also suggest that inputs are routed to, and encoded by, different sites within the hippocampus depending upon the pattern of activity arriving over the parent axon.


Assuntos
Giro Denteado , Potenciação de Longa Duração , Masculino , Camundongos , Animais , Potenciação de Longa Duração/fisiologia , Giro Denteado/fisiologia , Potenciais Pós-Sinápticos Excitadores/fisiologia , Hipocampo/metabolismo , Plasticidade Neuronal/fisiologia , Estimulação Elétrica/métodos
2.
Med Oral Patol Oral Cir Bucal ; 26(6): e762-e769, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34023839

RESUMO

BACKGROUND: The objective of this study was to analyse the association between oral and general health variables and obesity indicators with the sensation of dry mouth or xerostomia as evaluated on the Xerostomia Inventory (XI). MATERIAL AND METHODS: A total of 354 randomly selected subjects participated in this cross-sectional pilot study and completed an anonymous questionnaire. Anthropometric, clinical, and xerostomic variables were evaluated. Kruskal-Wallis, ANOVA and Bonferroni test were used for multiple comparisons. ROC curves and multinomial logistic regression were used to determine the (OR) risk of xerostomia. RESULTS: A total of 30.7 % of respondents reported xerostomia based on XI. The dry mouth question, the XI taken as a "gold standard", showed a diagnostic sensitivity of 70.37 %, and a specificity of 83.27 % (AUC=0.768, p<0.001). Logistical regression showed the highest xerostomia OR was associated to patients with bad self-perceived health, 6.31 (CI 95% 2.89-13.80, p<0.001). In the model adjusted for tooth mobility, bone or respiratory diseases, and the consumption of anxiolytics and antidepressants, the OR was 3.46 (CI 95% 1.47-8.18, p=0.005). CONCLUSIONS: a high prevalence of xerostomia was found in this cross-sectional pilot study, which was significantly more frequent in women, and increased with age. Xerostomia was associated to several systemic diseases, psychological conditions, and oral functional disorders such as tooth mobility. These preliminary results can serve as the basis for developing guidelines for the application of innovative measures designed to improve the quality of life of individuals with xerostomia.


Assuntos
Qualidade de Vida , Xerostomia , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Obesidade/complicações , Obesidade/epidemiologia , Projetos Piloto , Inquéritos e Questionários , Xerostomia/epidemiologia , Xerostomia/etiologia
3.
Med Oral Patol Oral Cir Bucal ; 25(3): e318-e325, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32134896

RESUMO

BACKGROUND: The relation between periodontal disease and systemic pathologies is still not widespread among general practitioners. The aim of our study is to evaluate whether or not periodontal radiological diagnosis can aid the detection of blood alterations associated with acquired systemic diseases. MATERIAL AND METHODS: This is a cross sectional study. All of the participants underwent a panoramic radiograph and a complete blood test. Morphological bone loss was considered as positive in those patients who showed radiographically more than 1 tooth with bone loss greater than or equal to the middle third of the root. The statistical analysis was performed by comparing the variables using the ANOVA or U-Mann-Whitney tests for independent samples with normal conditions. The correlation coefficient was analysed using the Pearson test. RESULTS: 239 patients were included in our study (96 men and 143 women) with an average age of 64.40 years. 59.04% of the patients were determined as morphological bone loss positive and had on average 4 teeth less than negative patients (p <0.0001). Also the average platelet levels in positive patients were lower (p = 0.024) and mean levels of HBA1c (p = 0.009) were higher. CONCLUSIONS: Morphological bone loss parameter can be useful both for dentists and general practitioners to refer, subsequently, to periodontal specialist.


Assuntos
Perda do Osso Alveolar , Processo Alveolar , Estudos Transversais , Feminino , Hemoglobinas Glicadas , Testes Hematológicos , Humanos , Masculino , Pessoa de Meia-Idade
4.
Phys Rev Lett ; 121(25): 257002, 2018 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-30608781

RESUMO

To trace the origin of time-reversal symmetry breaking (TRSB) in Re-based superconductors, we performed comparative muon-spin rotation and relaxation (µSR) studies of superconducting noncentrosymmetric Re_{0.82}Nb_{0.18} (T_{c}=8.8 K) and centrosymmetric Re (T_{c}=2.7 K). In Re_{0.82}Nb_{0.18}, the low-temperature superfluid density and the electronic specific heat evidence a fully gapped superconducting state, whose enhanced gap magnitude and specific-heat discontinuity suggest a moderately strong electron-phonon coupling. In both Re_{0.82}Nb_{0.18} and pure Re, the spontaneous magnetic fields revealed by zero-field µSR below T_{c} indicate time-reversal symmetry breaking and thus unconventional superconductivity. The concomitant occurrence of TRSB in centrosymmetric Re and noncentrosymmetric ReT (T=transition metal), yet its preservation in the isostructural noncentrosymmetric superconductors Mg_{10}Ir_{19}B_{16} and Nb_{0.5}Os_{0.5}, strongly suggests that the local electronic structure of Re is crucial for understanding the TRSB superconducting state in Re and ReT. We discuss the superconducting order parameter symmetries that are compatible with the experimental observations.

5.
Surg Radiol Anat ; 39(7): 717-723, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27933368

RESUMO

PURPOSE: To analyze anatomical variations of the greater palatine canal (GPC) using cone beam computed tomography (CBCT) images. METHODS: This study included 110 CBCTs. Axial slices were used to determine the shape of GPC and the number of lesser palatine foramina (LPF). Sagittal slices were used to assess the shape of the GPC and the number of lesser palatine canals (LPCs). RESULTS: The most prevalent axial and sagittal GPC shapes were oval (46.36%) and hourglass (23.64%). Most GPCs presented one LPF (47.27%) and one LPC (90.91%). CONCLUSIONS: GPC anatomy is highly variable. CBCT is a useful tool for evaluating the anatomical variations of GPC.


Assuntos
Boca/anatomia & histologia , Fossa Pterigopalatina/anatomia & histologia , Variação Anatômica , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Masculino , Boca/diagnóstico por imagem , Fossa Pterigopalatina/diagnóstico por imagem
6.
Phys Rev Lett ; 117(2): 027001, 2016 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-27447519

RESUMO

The nature of the pairing states of superconducting LaNiC_{2} and LaNiGa_{2} has to date remained a puzzling question. Broken time reversal symmetry has been observed in both compounds and a group theoretical analysis implies a nonunitary triplet pairing state. However, all the allowed nonunitary triplet states have nodal gap functions but most thermodynamic and NMR measurements indicate fully gapped superconductivity in LaNiC_{2}. Here we probe the gap symmetry of LaNiGa_{2} by measuring the London penetration depth, specific heat, and upper critical field. These measurements demonstrate two-gap nodeless superconductivity in LaNiGa_{2}, suggesting that this is a common feature of both compounds. These results allow us to propose a novel triplet superconducting state, where the pairing occurs between electrons of the same spin, but on different orbitals. In this case the superconducting wave function has a triplet spin component but isotropic even parity gap symmetry, yet the overall wave function remains antisymmetric under particle exchange. This model leads to a nodeless two-gap superconducting state which breaks time reversal symmetry, and therefore accounts well for the seemingly contradictory experimental results.

7.
Surg Radiol Anat ; 37(7): 825-33, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25821035

RESUMO

PURPOSE: This descriptive retrospective study analyzed differences among sagittal, coronal and axial NC groups based on the dimensions of nasopalatine canal (NC), buccal bone plate (BBP) and palatal bone plate (PBP) to canal. METHODS: Measurements were made on 224 CBCTs for NC, BBP and PBP on the three anatomic planes at three levels: level 1, when the incisive foramen is completely closed on the axial plane; level 2, at the midpoint of NC length (NCL) on the sagittal plane; and level 3, at the foramina of Stenson on the sagittal plane. ANOVA tests with post hoc tests were used. The intraclass correlation coefficient and Kappa test were used for evaluating the intraobserver agreement. RESULTS: Regarding coronal classification, these significant differences were found: BBP length (BL)level 1 was lower for the two parallel canals group; PBP length (PL)level 1 was lower for single canal group; and NCL was lower for Y-type canal group. Regarding axial classification, these significant differences were found: LPlevel 1 was lower for 3.1-3 group; PBP width (PW)level 3 was the greatest for 3.1-3; and LPlevel 3 was lower for 1.1. CONCLUSIONS: Presurgical evaluation with CBCT in premaxillae region should include analysis on coronal and axial planes and not only on sagittal plane seeing as morphometric differences were found on coronal and axial planes. Following the morphological coronal classification, two parallel canals presented a higher NCL, a higher LP and a lower LV at inferior edge of alveolar ridge.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Imageamento Tridimensional , Maxila/diagnóstico por imagem , Nariz/diagnóstico por imagem , Palato Duro/diagnóstico por imagem , Adulto , Idoso , Análise de Variância , Estudos de Coortes , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Maxila/anatomia & histologia , Pessoa de Meia-Idade , Nariz/anatomia & histologia , Variações Dependentes do Observador , Palato Duro/anatomia & histologia , Cuidados Pré-Operatórios , Estudos Retrospectivos
8.
Surg Radiol Anat ; 37(10): 1217-24, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26104277

RESUMO

PURPOSE: To analyze greater palatine canal (GPC) dimensions using cone-beam computed tomography (CBCT) images, and to evaluate the position of the greater palatine foramen (GPF) with respect to various landmarks selected in relation to dental status. METHODS: This study included 150 CBCTs. Axial slices were used to determine the position and dimensions of the GPF. Sagittal slices were used to assess GPC length. Reference lines were established to evaluate the GPC diameter in sagittal and coronal slices. RESULTS: From the 77 GPF analyzed, 76 were located on level 2. Average posterior GPF distance was 6.59 ± 3.27 mm on right side and 7.35 ± 3.40 mm on left side. Several measurements to determine the position and dimensions of the GPF presented significant values (p ≤ 0.05). GPC length was 12.31 ± 1.96 mm on right side and 12.52 ± 2.15 mm on left side, statistically significant differences were detected between genders only on right canal (p ≤ 0.004). Sagittal and coronal reference lines presented significantly higher values for men except for the S3 (p < 0.062) and C1 (p < 0.067) in the left GPC. CONCLUSIONS: CBCT is a useful tool for evaluating GPC morphometrically in the three anatomical slices. The sagittal nasal plane and posterior nasal plane are two intraoral anatomical landmarks for the location of the GPF. Their scant variability allows accurate identification of GPFs in both dentate as well as edentulous patients.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Palato Duro/diagnóstico por imagem , Adulto , Feminino , Humanos , Masculino
9.
Phys Rev Lett ; 112(10): 107002, 2014 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-24679322

RESUMO

We have investigated the superconducting state of the noncentrosymmetric compound Re6Zr using magnetization, heat capacity, and muon-spin relaxation or rotation (µSR) measurements. Re6Zr has a superconducting transition temperature, Tc=6.75±0.05 K. Transverse-field µSR experiments, used to probe the superfluid density, suggest an s-wave character for the superconducting gap. However, zero and longitudinal-field µSR data reveal the presence of spontaneous static magnetic fields below Tc indicating that time-reversal symmetry is broken in the superconducting state and an unconventional pairing mechanism. An analysis of the pairing symmetries identifies the ground states compatible with time-reversal symmetry breaking.

10.
Surg Radiol Anat ; 36(9): 895-905, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24752396

RESUMO

PURPOSE: For dental implant treatment planning and placement, a precise anatomic description of the nasopalatine canal (NC) is necessary. This descriptive retrospective study evaluated dimensions of the NC and buccal bone plate (BBP) and the tridimensional association of the anatomic variants of NC, using cone-beam computed tomography (CBCT). METHODS: This study included 230 CBCTs. Sagittal slices were used for measurements of the NC and BBP and to evaluate shape and direction-course of the NC. Coronal slices were used to assess NC shape and axial slices to assess number of incisive foramina and foramina of Stenson. RESULTS: Mean NC length was 12.34 ± 2.79 mm, statistically significant differences were detected between genders (p < 0.001). Mean BBP length was 20.87 ± 3.68 mm, statistically significant differences were found for the dental status (p < 0.001) and mean BBP width was 6.83 ± 1.28 mm, significant differences were detected between genders (p < 0.001). Mean nasopalatine angle was 73.33° ± 8.11°, significant differences were found in sagittal and coronal classifications. The most prevalent canal was: cylindrical sagittal shape (48.2 %); slanted-straight direction-course (57.6 %); Ya-type coronal shape (42.4 %); and one foramen incisive with two Stenson's foramina (1-2) (50.9 %). Sagittal shape was associated with sagittal direction-course (p < 0.001). Coronal shape was associated with axial classification (p < 0.001). CONCLUSIONS: The NC anatomy is highly variable. Gender is related to the NC length and BBP width, while dental status is related to BBP length. There was an association between the different sagittal classifications of the NC and between the coronal shape and axial classification.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Imageamento Tridimensional , Maxila/diagnóstico por imagem , Nariz/diagnóstico por imagem , Palato/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Pontos de Referência Anatômicos , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Maxila/anatomia & histologia , Pessoa de Meia-Idade , Nariz/anatomia & histologia , Palato/anatomia & histologia , Estudos Retrospectivos , Fatores Sexuais , Adulto Jovem
11.
Eur J Surg Oncol ; 50(7): 108395, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38735236

RESUMO

The study of circulating tumor DNA (ctDNA) plays a pivotal role in advancing precision oncology, providing valuable information for individualized patient care and contributing to the ongoing effort to improve cancer diagnosis, treatment, and management. However, its applicability in pseudomyxoma peritonei (PMP) remains unexplored. In this multicenter retrospective study involving 21 PMP patients, we investigated ctDNA presence in peripheral blood using three distinct methodologies. Despite mucinous tumor tissues exhibiting KRAS and GNAS mutations, ctDNA for these mutations was undetectable in blood samples. In this pilot study, circulating tumor DNA was not detected in blood when the tumor harbored mutations of known significance. In the future, a study with a larger sample size is needed to confirm these findings and to determine whether ctDNA could identify patients at risk for early recurrence and/or systemic metastases.


Assuntos
DNA Tumoral Circulante , Neoplasias Peritoneais , Pseudomixoma Peritoneal , Humanos , Pseudomixoma Peritoneal/genética , Pseudomixoma Peritoneal/sangue , Pseudomixoma Peritoneal/patologia , Neoplasias Peritoneais/genética , Neoplasias Peritoneais/secundário , Neoplasias Peritoneais/sangue , DNA Tumoral Circulante/genética , DNA Tumoral Circulante/sangue , Estudos Retrospectivos , Feminino , Pessoa de Meia-Idade , Masculino , Idoso , Subunidades alfa Gs de Proteínas de Ligação ao GTP/genética , Cromograninas/genética , Mutação , Proteínas Proto-Oncogênicas p21(ras)/genética , Projetos Piloto , Adulto
12.
Neurologia (Engl Ed) ; 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37116689

RESUMO

BACKGROUND: In addition to stent retrievers, direct aspiration has become a reasonable thrombectomy strategy. OBJECTIVES: We carried out the thrombectomy by guiding the aspiration catheter fully over the clot and performing immediate manual aspiration; we call this procedure "embed aspiration". METHODS: In this prospective, non-randomised, single-centre study, we included all patients treated at a high volume-of-care stroke centre between 2017 and 2018 for the TRIANA (Thrombectomy in Andalusia using Aspiration) registry. Thrombectomy was carried out by embed aspiration. Patients were classified according to the success (eTICI 2b67-2c-3) or failure (eTICI 0-1-2a-2b50) of the procedure. Baseline clinical data and outcomes were compared, and multivariate analysis was performed. RESULTS: The embed aspiration technique was used in 370 patients. Treatment was successful in 90.3% of patients. Mean puncture-to-recanalisation time was 25 minutes. The overall rate of good outcomes (mRS 0-2) at 3 months was 64%. CONCLUSIONS: This study supports real-life evidence that standardised embed aspiration may be an alternative to stent retrievers for thrombectomy.

13.
Phys Rev Lett ; 109(9): 097001, 2012 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-23002872

RESUMO

Muon spin rotation and relaxation experiments on the centrosymmetric intermetallic superconductor LaNiGa2 are reported. The appearance of spontaneous magnetic fields coincides with the onset of superconductivity, implying that the superconducting state breaks time reversal symmetry, similarly to noncentrosymmetric LaNiC2. Only four triplet states are compatible with this observation, all of which are nonunitary triplets. This suggests that LaNiGa2 is the centrosymmetric analogue of LaNiC2. We argue that these materials are representatives of a new family of paramagnetic nonunitary superconductors.

14.
Radiologia (Engl Ed) ; 64(2): 169-178, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35504683

RESUMO

Mónico Sánchez Moreno (1880-1961) was an important figure in the early years of electromedicine, rubbing elbows with world-class physicists like Nikola Tesla. Her main contribution to the field was the invention and commercialization of a portable X-ray generator, replacing the heavy transformer had been necessary to generate power with a lightweight portable device that could work with direct or alternating current at 220 or 125V. This device was easily adaptable to other applications in electromedicine, such as cauterization or disinfection. This indefatigable entrepreneur could have triumphed in America, but preferred to work toward furthering technological development in the land that she loved. Her efforts made it possible to have an affordable device made in Spain that would allow radiological examinations to be done in places where it would have been otherwise unthinkable. In conclusion, Mónico Sánchez Moreno was a self-made woman who deserves to be remembered for her pioneering role in portable radiology.


Assuntos
Radiologia , Tecnologia Radiológica , Feminino , Humanos , Espanha
15.
Front Physiol ; 13: 837661, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36225294

RESUMO

Exposure to adverse childhood experiences or early life stress experiences (ELSs) increase the risk of non-adaptive behaviors and psychopathology in adulthood. Environmental enrichment (EE) has been proposed to minimize these effects. The vast number of methodological variations in animal studies underscores the lack of systematicity in the studies and the need for a detailed understanding of how enrichment interacts with other variables. Here we evaluate the effects of environmental enrichment in male and female Wistar rats exposed to adverse early life experiences (prenatal, postnatal, and combined) on emotional (elevated plus maze), social (social interaction chamber), memory (Morris water maze) and flexibility tasks. Our results-collected from PND 51 to 64-confirmed: 1) the positive effect of environmental enrichment (PND 28-49) on anxiety-like behaviors in animals submitted to ELSs. These effects depended on type of experience and type of enrichment: foraging enrichment reduced anxiety-like behaviors in animals with prenatal and postnatal stress but increased them in animals without ELSs. This effect was sex-dependent: females showed lower anxiety compared to males. Our data also indicated that females exposed to prenatal and postnatal stress had lower anxious responses than males in the same conditions; 2) no differences were found for social interactions; 3) concerning memory, there was a significant interaction between the three factors: A significant interaction for males with prenatal stress was observed for foraging enrichment, while physical enrichment was positive for males with postnatal stress; d) regarding cognitive flexibility, a positive effect of EE was found in animals exposed to adverse ELSs: animals with combined stress and exposed to physical enrichment showed a higher index of cognitive flexibility than those not exposed to enrichment. Yet, within animals with no EE, those exposed to combined stress showed lower flexibility than those exposed to both prenatal stress and no stress. On the other hand, animals with prenatal stress and exposed to foraging-type enrichment showed lower cognitive flexibility than those with no EE. The prenatal stress-inducing conditions used here 5) did not induced fetal or maternal problems and 6) did not induced changes in the volume of the dentate gyrus of the hippocampus.

16.
J Periodontal Res ; 46(1): 82-8, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21108641

RESUMO

BACKGROUND AND OBJECTIVE: The present study was designed to investigate the influence of occlusal forces on radicular resorption in teeth with periodontal disease. The occlusal forces are a cause in the aggravation of the periodontal disease and therefore influences in the increase the extension and the depth of the radicular resorption. MATERIAL AND METHODS: We quantified radicular resorption, its extension across the radicular surface and its depth, in 88 teeth with periodontal disease with and without occlusal contact, pertaining to patients between 43 and 91 years of age. A histological method was used to obtain 6-µm-thick sections. The sections were observed under an Olympus BX40 optical microscope and processed by an image analysis program. Measurements of length and area were used to calculate the percentages of surface and volume of cement reabsorbed. RESULTS: In both groups presenting periodontal pathology (groups 2 and 3) the percentages of the surface and volume of reabsorbed cement were greater in those teeth with antagonist contact. The greatest percentages of radicular resorption were observed in teeth of group 3 showing antagonism. CONCLUSION: The severity of periodontal disease increases the extension and the depth of the radicular resorption, and the presence of antagonist forces aggravates the resorption.


Assuntos
Força de Mordida , Oclusão Dentária Traumática/complicações , Doenças Periodontais/complicações , Reabsorção da Raiz/etiologia , Reabsorção da Raiz/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Cemento Dentário/patologia , Análise do Estresse Dentário , Humanos , Processamento de Imagem Assistida por Computador , Pessoa de Meia-Idade , Estatísticas não Paramétricas
17.
J Fish Biol ; 79(4): 896-914, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21967580

RESUMO

A combined study of Alborán Sea Sardina pilchardus larval daily growth and isotopic signature was carried out to elucidate the cause of morphometric differences observed in a single larval school whereby the standard length (L(S)) v. dry mass (M(D)) relationship differentiated a heavier-by-size larval group from a lighter larval group. The daily growth analysis revealed that this difference originated from two larval growth patterns, where a fast growing population (F) in contrast to a slow-growing larval population (S) was distinguished. The S-growing larval cohort had a significantly higher nitrogen (N) content as a result of greater somatic mass build up with time in the form of structural proteins. Alternatively, the F-growing population showed a significantly greater amount of carbon (C) content with age, indicating faster metabolic rates of C accretion compared to the S-growing group. In consequence, the C:N ratios of the F-growing larvae were significantly higher than the S-group. C:N ratios of both larval populations showed significant linear decrease with age (and size), while K showed an inverse relationship. The stable isotopes of N did not show significant differences between the S and F-growing larvae. In F-growing larvae, however, a significant linear increase in δ(15)N (by age class) was observed, indicating that as larvae undergo ontogenetic development, trophic level tends to increase. This was also made evident by the significant decrease in age of δ(15)N coefficients of variation (by age class). The higher δ(13)C values in the S-growing larvae were related to the lower growth rates observed in this group. These results suggest a broader trophic flexibility in younger larvae, but moving towards a trophic specialization and more selective diets with age. This trophic specialization shows a tendency of a greater prey size with age. These findings suggest that S-growing larvae have a more omnivorous diet than the F-growing ones.


Assuntos
Isótopos de Carbono/análise , Peixes/crescimento & desenvolvimento , Peixes/metabolismo , Isótopos de Nitrogênio/análise , Fatores Etários , Animais , Dieta , Comportamento Predatório
18.
Radiologia (Engl Ed) ; 2021 Jul 28.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-34332785

RESUMO

Mónico Sánchez Moreno (1880-1961) was an important figure in the early years of electromedicine, rubbing elbows with world-class physicists like Nikola Tesla. Her main contribution to the field was the invention and commercialization of a portable X-ray generator, replacing the heavy transformer had been necessary to generate power with a lightweight portable device that could work with direct or alternating current at 220 or 125V. This device was easily adaptable to other applications in electromedicine, such as cauterization or disinfection. This indefatigable entrepreneur could have triumphed in America, but preferred to work toward furthering technological development in the land that she loved. Her efforts made it possible to have an affordable device made in Spain that would allow radiological examinations to be done in places where it would have been otherwise unthinkable. In conclusion, Mónico Sánchez Moreno was a self-made woman who deserves to be remembered for her pioneering role in portable radiology.

19.
J Phys Condens Matter ; 33(19)2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33545697

RESUMO

In recent years, artificial intelligence techniques have proved to be very successful when applied to problems in physical sciences. Here we apply an unsupervised machine learning (ML) algorithm called principal component analysis (PCA) as a tool to analyse the data from muon spectroscopy experiments. Specifically, we apply the ML technique to detect phase transitions in various materials. The measured quantity in muon spectroscopy is an asymmetry function, which may hold information about the distribution of the intrinsic magnetic field in combination with the dynamics of the sample. Sharp changes of shape of asymmetry functions-measured at different temperatures-might indicate a phase transition. Existing methods of processing the muon spectroscopy data are based on regression analysis, but choosing the right fitting function requires knowledge about the underlying physics of the probed material. Conversely, PCA focuses on small differences in the asymmetry curves and works without any prior assumptions about the studied samples. We discovered that the PCA method works well in detecting phase transitions in muon spectroscopy experiments and can serve as an alternative to current analysis, especially if the physics of the studied material are not entirely known. Additionally, we found out that our ML technique seems to work best with large numbers of measurements, regardless of whether the algorithm takes data only for a single material or whether the analysis is performed simultaneously for many materials with different physical properties.

20.
Ann Anat ; 232: 151582, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32810612

RESUMO

BACKGROUND: The Chievitz's organ or juxta-oral organ is a mysterious bilateral structure, phylogenetically preserved, which develops from the mouth epithelium as an invagination that loses connection to it in the prenatal period. It is located laterally to the walls of the oral cavity in an imprecise anatomical location and receives abundant innervation from the buccal nerve. Structurally it consists of non-keratinizing squamous-like neuroepithelial cells surrounded by two layers of connective tissue with nerve fibers and different morphotypes of sensory corpuscles. Its function is completely unknown although based on its rich innervation it is assumed that works as a mechanoreceptor. METHODS: We have performed immunohistochemistry for axonal and Schwann cells, and the putative mechanoproteins ASIC2, TRPV4 and Piezo2 in sections of fetal juxta-oral organ. RESULTS: Intraparenchymatous nerve fibers and sensory corpuscles were observed as well as immunoreactivity for Piezo2 in both nerve fibers and epithelial parenchymatous cells. CONCLUSIONS: We add indirect evidence that the juxtaoral organ is a mechanoreceptor because in addition to its dense innervation, the epithelial cells and sensory nerve fibers display immunoreactivity for the mechanogated ion channel Piezo2. Based on current knowledge, the functional and clinical importance of the juxta-oral organ should be further investigated.


Assuntos
Bochecha/anatomia & histologia , Bochecha/embriologia , Bochecha/patologia , Bochecha/fisiologia , Feto/anatomia & histologia , Humanos , Imuno-Histoquímica , Canais Iônicos de Abertura Ativada por Ligante/fisiologia , Tecido Parenquimatoso/anatomia & histologia , Tecido Parenquimatoso/inervação
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