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1.
Article in English | LILACS-Express | LILACS | ID: biblio-1535342

ABSTRACT

Objective: To explore the training and use of auditory perceptual evaluation of the voice reported by Colombian speech-language pathologists. Study Design: Cross-sectional observational research with a quantitative approach. Methods: A digital questionnaire was designed and distributed to gather information regarding professionals' training process and implementation of auditory-perceptual evaluation procedures. Descriptive statistics were applied, and several generalized linear models were adjusted to determine the influence of certain variables on others. Results: The survey received responses from 40 speech-language pathologists, revealing that the most used scales for training and evaluating vocal quality within this group are direct magnitude estimations (82.5% and 77.5%). Similarly, in this group, the tasks most frequently used to train and use as an evaluation strategy are vowel assessments (38%) followed by spontaneous speech (30%). Practitioners of this group were mostly trained using a conceptual framework involving multiple exposures to rating (42.5%). The use of direct magnitude estimation in training with a normal voice showed significance (p = 0.015), as did the use of the vowel /i/ in training with an equal-appearing interval (p = 0.013). The statistical models relating the scale used to the scale on which participants were trained were also significant (p < 0.05). Conclusions: The GRBAS scale is the training tool most used by the group of speech-language pathologists of the study group in Colombia. Future efforts should focus on improving training practices for auditory-perceptual evaluation, exploring alternative conceptual frameworks, and incorporating external references to enhance validity and reliability.


Objetivo: Explorar los reportes de fonoaudiólogos colombianos acerca del entrenamiento y uso de la evaluación perceptual auditiva de la voz. Diseño de estudio: Se eligió un diseño de investigación observacional transversal con un enfoque cuantitativo. Metodología: Se diseñó y distribuyó un cuestionario digital para recopilar información sobre el proceso de formación de los profesionales y la implementación de procedimientos de evaluación perceptual auditiva. Se aplicaron estadísticas descriptivas y se ajustaron varios modelos lineales generalizados para determinar la influencia de ciertas variables en otras. Resultados: La encuesta recibió respuestas de 40 fonoaudiólogos, revelando que las escalas más utilizadas para la formación y la evaluación de la calidad vocal en el grupo son las estimaciones de magnitud directa (82.5% y 77.5%). Del mismo modo, en este grupo las tareas más frecuentemente utilizadas para la formación y el uso como estrategia de evaluación son las vocales (38%), seguidas por el habla espontánea (30%). La mayoría de los profesionales del grupo fueron formados utilizando un marco conceptual que involucra múltiples exposiciones a la calificación (42.5%). El uso de la estimación de magnitud directa en la formación con una voz normal mostró significancia (p = 0.015), al igual que el uso de la vocal /i/ en la formación con intervalos de igual apariencia (p = 0.013). Los modelos estadísticos que relacionan la escala utilizada con la escala en la que los participantes fueron entrenados también fueron significativos (p < 0.05). Conclusiones: La escala GRBAS es la herramienta de formación más utilizada por el grupo de fonoaudiólogos del estudio. Los esfuerzos futuros deberían centrarse en mejorar las prácticas de formación para la evaluación perceptual auditiva, explorar marcos conceptuales alternativos e incorporar referencias externas para mejorar la validez y la confiabilidad.

2.
PLoS One ; 19(5): e0303802, 2024.
Article in English | MEDLINE | ID: mdl-38768189

ABSTRACT

The innovative performance of manufacturing and service companies can be impacted by the existing relationship between open innovation (OI) and the generation of confidentiality agreements (NDAs) as a tool for the protection of intellectual property. Based on the analysis of a cross-sectional sample of 6,798 industrial companies (2019-2020) and 9,304 companies in the service sector (2017-2019) that are part of the directory of the National Administrative Department of Statistics (DANE) in its Technological Innovation and Development Survey (EDIT and EDITS), it can be suggested that the interaction of these two variables (OI and NDAs) generate positive effects for the manufacturing industry but negative ones for the service sector. It could be deduced that the positive effect is due to the greater tradition of OI in the manufacturing industry and the negative effect to the caution that the service sector presents when collaborating with external actors.


Subject(s)
Confidentiality , Humans , Cross-Sectional Studies , Manufacturing Industry , Inventions , Intellectual Property , Industry , Surveys and Questionnaires
3.
Nat Commun ; 15(1): 1974, 2024 Mar 04.
Article in English | MEDLINE | ID: mdl-38438350

ABSTRACT

Artificial Intelligence (AI) is currently experiencing a bloom driven by deep learning (DL) techniques, which rely on networks of connected simple computing units operating in parallel. The low communication bandwidth between memory and processing units in conventional von Neumann machines does not support the requirements of emerging applications that rely extensively on large sets of data. More recent computing paradigms, such as high parallelization and near-memory computing, help alleviate the data communication bottleneck to some extent, but paradigm- shifting concepts are required. Memristors, a novel beyond-complementary metal-oxide-semiconductor (CMOS) technology, are a promising choice for memory devices due to their unique intrinsic device-level properties, enabling both storing and computing with a small, massively-parallel footprint at low power. Theoretically, this directly translates to a major boost in energy efficiency and computational throughput, but various practical challenges remain. In this work we review the latest efforts for achieving hardware-based memristive artificial neural networks (ANNs), describing with detail the working principia of each block and the different design alternatives with their own advantages and disadvantages, as well as the tools required for accurate estimation of performance metrics. Ultimately, we aim to provide a comprehensive protocol of the materials and methods involved in memristive neural networks to those aiming to start working in this field and the experts looking for a holistic approach.

4.
Genome Biol Evol ; 15(11)2023 Nov 01.
Article in English | MEDLINE | ID: mdl-37935115

ABSTRACT

Climatic changes have caused major environmental restructuring throughout the world's oceans. Marine organisms have responded to novel conditions through various biological systems, including genomic adaptation. Growing accessibility of next-generation DNA sequencing methods to study nonmodel species has recently allowed genomic changes underlying environmental adaptations to be investigated. This study used double-digest restriction-site associated DNA (ddRAD) sequence data to investigate the genomic basis of ecotype formation across currently recognized species and subspecies of bottlenose dolphins (genus Tursiops) in the Southern Hemisphere. Subspecies-level genomic divergence was confirmed between the offshore common bottlenose dolphin (T. truncatus truncatus) and the inshore Lahille's bottlenose dolphin (T. t. gephyreus) from the southwestern Atlantic Ocean (SWAO). Similarly, subspecies-level divergence is suggested between inshore (eastern Australia) Indo-Pacific bottlenose dolphin (T. aduncus) and the proposed Burrunan dolphin (T. australis) from southern Australia. Inshore bottlenose dolphin lineages generally had lower genomic diversity than offshore lineages, a pattern particularly evident for T. t. gephyreus, which showed exceptionally low diversity. Genomic regions associated with cardiovascular, musculoskeletal, and energy production systems appear to have undergone repeated adaptive evolution in inshore lineages across the Southern Hemisphere. We hypothesize that comparable selective pressures in the inshore environment drove similar adaptive responses in each lineage, supporting parallel evolution of inshore bottlenose dolphins. With climate change altering marine ecosystems worldwide, it is crucial to gain an understanding of the adaptive capacity of local species and populations. Our study provides insights into key adaptive pathways that may be important for the long-term survival of cetaceans and other organisms in a changing marine environment.


Subject(s)
Bottle-Nosed Dolphin , Animals , Bottle-Nosed Dolphin/genetics , Ecosystem , Ecotype , Cetacea , Genomics
5.
Arch. argent. pediatr ; 121(5): e202202801, oct. 2023. tab, ilus
Article in English, Spanish | LILACS, BINACIS | ID: biblio-1509956

ABSTRACT

Las hemoglobinopatías son trastornos genéticos que afectan a la molécula de hemoglobina (Hb). Las mutaciones en las cadenas a o b que alteran el tetrámero de Hb pueden modificar la capacidad de la molécula para unirse al oxígeno. Las hemoglobinopatías con baja afinidad al oxígeno pueden presentarse con cianosis y una lectura alterada de la oximetría de pulso, lo que lleva a pruebas innecesarias y, a veces, invasivas para descartar afecciones cardiovasculares y respiratorias. En el siguiente reporte de caso, presentamos a una paciente pediátrica, asintomática, que se presentó a la consulta por detección de desaturación en oximetría de pulso. Las pruebas de laboratorio iniciales mostraron una anemia normocítica, normocrómica. Las muestras de gas venoso demostraron una p50 elevada. Después de extensas herramientas de diagnóstico, se diagnosticó una variante de Hb con baja afinidad al oxígeno, Hb Denver.


Hemoglobinopathies are genetic disorders that affect the hemoglobin (Hb) molecule. Mutations in the alpha or beta chains altering the Hb tetramer may modify the molecule's oxygen-binding capacity. Hemoglobinopathies with low oxygen affinity may occur with cyanosis and an altered pulse oximetry reading, leading to unnecessary and sometimes invasive tests to rule out cardiovascular and respiratory conditions. In the case report described here, we present an asymptomatic pediatric patient who consulted for desaturated pulse oximetry. Her initial laboratory tests showed normocytic, normochromic anemia. Venous blood gas samples showed an elevated p50. After using extensive diagnostic tools, a variant of Hb with low oxygen affinity was diagnosed: Hb Denver.


Subject(s)
Humans , Female , Child , Hemoglobins, Abnormal/analysis , Hemoglobins, Abnormal/genetics , Hemoglobins, Abnormal/chemistry , Hemoglobinopathies/diagnosis , Hemoglobinopathies/genetics , Anemia , Oxygen , Oximetry
6.
Arch Argent Pediatr ; 121(5): e202202801, 2023 10 01.
Article in English, Spanish | MEDLINE | ID: mdl-36857142

ABSTRACT

Hemoglobinopathies are genetic disorders that affect the hemoglobin (Hb) molecule. Mutations in the alpha or beta chains altering the Hb tetramer may modify the molecule's oxygen-binding capacity. Hemoglobinopathies with low oxygen affinity may occur with cyanosis and an altered pulse oximetry reading, leading to unnecessary and sometimes invasive tests to rule out cardiovascular and respiratory conditions. In the case report described here, we present an asymptomatic pediatric patient who consulted for desaturated pulse oximetry. Her initial laboratory tests showed normocytic, normochromic anemia. Venous blood gas samples showed an elevated p50. After using extensive diagnostic tools, a variant of Hb with low oxygen affinity was diagnosed: Hb Denver.


Las hemoglobinopatías son trastornos genéticos que afectan a la molécula de hemoglobina (Hb). Las mutaciones en las cadenas a o b que alteran el tetrámero de Hb pueden modificar la capacidad de la molécula para unirse al oxígeno. Las hemoglobinopatías con baja afinidad al oxígeno pueden presentarse con cianosis y una lectura alterada de la oximetría de pulso, lo que lleva a pruebas innecesarias y, a veces, invasivas para descartar afecciones cardiovasculares y respiratorias. En el siguiente reporte de caso, presentamos a una paciente pediátrica, asintomática, que se presentó a la consulta por detección de desaturación en oximetría de pulso. Las pruebas de laboratorio iniciales mostraron una anemia normocítica, normocrómica. Las muestras de gas venoso demostraron una p50 elevada. Después de extensas herramientas de diagnóstico, se diagnosticó una variante de Hb con baja afinidad al oxígeno, Hb Denver.


Subject(s)
Anemia , Hemoglobinopathies , Hemoglobins, Abnormal , Humans , Child , Female , Hemoglobins, Abnormal/genetics , Hemoglobins, Abnormal/analysis , Hemoglobins, Abnormal/chemistry , Oximetry , Hemoglobinopathies/diagnosis , Hemoglobinopathies/genetics , Oxygen
7.
Rev Bras Ortop (Sao Paulo) ; 58(1): 85-91, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36969781

ABSTRACT

Objective To analyze the dimensions of the posterior cruciate ligament (PCL), anterior cruciate ligament (ACL), the presence of meniscus-femoral ligaments MFLs in human knees, and the correlation with the dimensions of the knee skeleton. Methods Anatomical study on 29 specimens of human knees in which we measured the length and width of the cruciate and meniscus-femoral ligaments and the dimensions of femoral and tibia condyles and the femoral notch. The ACL length was calculated with different degrees of knee flexion. The relationship between the ligaments and bone dimensions were analyzed. Results The length of the ACL and the PCL were similar. Posterior MFL was more frequent and longer than the anterior MFL. We found the posterior MFL in the 72.41% of the knees and anterior MFL in 20.69%. The ACL presented 30% of its maximum length up to 60°, approximately half of its length between 90° and 120°, reaching its maximum length at 170°. We found a strong correlation between the length of the ACL and that of the PCL ( p = 0.001). However, the lengths of the ACL and PCL were not related with the bone dimensions. Conclusion We have found no correlations between the cruciate and MFLs and the anatomical dimensions of the intercondylar notch and the proximal tibia and distal femur. The presence of the posterior MFL was more frequent and longer than that of the anterior ligament.

8.
Nature ; 618(7963): 57-62, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36972685

ABSTRACT

Exploiting the excellent electronic properties of two-dimensional (2D) materials to fabricate advanced electronic circuits is a major goal for the semiconductor industry1,2. However, most studies in this field have been limited to the fabrication and characterization of isolated large (more than 1 µm2) devices on unfunctional SiO2-Si substrates. Some studies have integrated monolayer graphene on silicon microchips as a large-area (more than 500 µm2) interconnection3 and as a channel of large transistors (roughly 16.5 µm2) (refs. 4,5), but in all cases the integration density was low, no computation was demonstrated and manipulating monolayer 2D materials was challenging because native pinholes and cracks during transfer increase variability and reduce yield. Here, we present the fabrication of high-integration-density 2D-CMOS hybrid microchips for memristive applications-CMOS stands for complementary metal-oxide-semiconductor. We transfer a sheet of multilayer hexagonal boron nitride onto the back-end-of-line interconnections of silicon microchips containing CMOS transistors of the 180 nm node, and finalize the circuits by patterning the top electrodes and interconnections. The CMOS transistors provide outstanding control over the currents across the hexagonal boron nitride memristors, which allows us to achieve endurances of roughly 5 million cycles in memristors as small as 0.053 µm2. We demonstrate in-memory computation by constructing logic gates, and measure spike-timing dependent plasticity signals that are suitable for the implementation of spiking neural networks. The high performance and the relatively-high technology readiness level achieved represent a notable advance towards the integration of 2D materials in microelectronic products and memristive applications.

9.
J Clin Oncol ; 41(14): 2561-2570, 2023 05 10.
Article in English | MEDLINE | ID: mdl-36821809

ABSTRACT

PURPOSE: In many cancers, the expression of immunomodulatory ligands leads to immunoevasion, as exemplified by the interaction of PD-L1 with PD-1 on tumor-infiltrating lymphocytes. Profound advances in cancer treatments have come with the advent of immunotherapies directed at blocking these immuno-suppressive ligand-receptor interactions. However, although there has been success in the use of these immune checkpoint interventions, correct patient stratification for these therapies has been challenging. MATERIALS AND METHODS: To address this issue of patient stratification, we have quantified the intercellular PD-1/PD-L1 interaction in formalin-fixed paraffin-embedded tumor samples from patients with non-small cell lung carcinoma, using a high-throughput automated quantitative imaging platform (quantitative functional proteomics [QF-Pro]). RESULTS: The multisite blinded analysis across a cohort of 188 immune checkpoint inhibitor-treated patients demonstrated the intra- and intertumoral heterogeneity of PD-1/PD-L1 immune checkpoint engagement and notably showed no correlation between the extent of PD-1/PD-L1 interaction and PD-L1 expression. Importantly, PD-L1 expression scores used clinically to stratify patients correlated poorly with overall survival; by contrast, patients showing a high PD-1/PD-L1 interaction had significantly better responses to anti-PD-1/PD-L1 treatments, as evidenced by increased overall survival. This relationship was particularly strong in the setting of first-line treatments. CONCLUSION: The functional readout of PD-1/PD-L1 interaction as a predictive biomarker for the stratification of patients with non-small-cell lung carcinoma, combined with PD-L1 expression, should significantly improve the response rates to immunotherapy. This would both capture patients excluded from checkpoint immunotherapy (high PD-1/PD-L1 interaction but low PD-L1 expression, 24% of patients) and additionally avoid treating patients who despite their high PD-L1 expression do not respond and suffer from side effects.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , Carcinoma, Non-Small-Cell Lung/drug therapy , Lung Neoplasms/drug therapy , Immunotherapy/methods , B7-H1 Antigen
10.
Rev. bras. ortop ; 58(1): 85-91, Jan.-Feb. 2023. tab, graf
Article in English | LILACS | ID: biblio-1441340

ABSTRACT

Abstract Objective To analyze the dimensions of the posterior cruciate ligament (PCL), anterior cruciate ligament (ACL), the presence of meniscus-femoral ligaments MFLs in human knees, and the correlation with the dimensions of the knee skeleton. Methods Anatomical study on 29 specimens of human knees in which we measured the length and width of the cruciate and meniscus-femoral ligaments and the dimensions of femoral and tibia condyles and the femoral notch. The ACL length was calculated with different degrees of knee flexion. The relationship between the ligaments and bone dimensions were analyzed. Results The length of the ACL and the PCL were similar. Posterior MFL was more frequent and longer than the anterior MFL. We found the posterior MFL in the 72.41% of the knees and anterior MFL in 20.69%. The ACL presented 30% of its maximum length up to 60°, approximately half of its length between 90° and 120°, reaching its maximum length at 170°. We found a strong correlation between the length of the ACL and that of the PCL (p= 0.001). However, the lengths of the ACL and PCL were not related with the bone dimensions. Conclusion We have found no correlations between the cruciate and MFLs and the anatomical dimensions of the intercondylar notch and the proximal tibia and distal femur. The presence of the posterior MFL was more frequent and longer than that of the anterior ligament.


Resumo Objetivo Analisar as dimensões do ligamento cruzado posterior (LCP), do ligamento cruzado anterior (LCA), a presença de ligamentos meniscofemorais (LMFs) em joelhos humanos e a correlação com as dimensões do esqueleto do joelho. Métodos Estudo anatômico em 29 espécimes de joelhos humanos nos quais medimos o comprimento e a largura dos ligamentos cruzado e meniscofemoral e as dimensões dos côndilos femorais e tibiais e do entalhe femoral. O comprimento do LCA foi calculado com diferentes graus de flexão do joelho. Analisou-se a relação entre os ligamentos e as dimensões ósseas. Resultados O comprimento do LCA e do LCP foram semelhantes, LMF posterior foi mais frequente e mais longo do que o LMF anterior. Foram encontradas LMF posterior em 72,41% dos joelhos e LMF anterior em 20,69%. O LCA apresentou 30% de seu comprimento máximo até 60°, aproximadamente metade de seu comprimento entre 90° e 120°, atingindo seu comprimento máximo com flexão de 170°. Encontramos uma forte correlação entre o comprimento do LCA e do LCP (p= 0,001). No entanto, os comprimentos do LCA e do LCP não estavam relacionados com as dimensões ósseas. Conclusão Não encontramos correlações entre os ligamentos cruzado e meniscofemoral e as dimensões anatômicas do entalhe intercondilar e da tíbia proximal e do fêmur distal. A presença do LMF posterior foi mais frequente e maior que a do ligamento anterior.


Subject(s)
Humans , Anterior Cruciate Ligament , Posterior Cruciate Ligament , Meniscus , Knee
11.
Nanoscale ; 15(5): 2171-2180, 2023 Feb 02.
Article in English | MEDLINE | ID: mdl-36628646

ABSTRACT

The development of the internet-of-things requires cheap, light, small and reliable true random number generator (TRNG) circuits to encrypt the data-generated by objects or humans-before transmitting them. However, all current solutions consume too much power and require a relatively large battery, hindering the integration of TRNG circuits on most objects. Here we fabricated a TRNG circuit by exploiting stable random telegraph noise (RTN) current signals produced by memristors made of two-dimensional (2D) multi-layered hexagonal boron nitride (h-BN) grown by chemical vapor deposition and coupled with inkjet-printed Ag electrodes. When biased at small constant voltages (≤70 mV), the Ag/h-BN/Ag memristors exhibit RTN signals with very low power consumption (∼5.25 nW) and a relatively high current on/off ratio (∼2) for long periods (>1 hour). We constructed TRNG circuits connecting an h-BN memristor to a small, light and cheap commercial microcontroller, producing a highly-stochastic, high-throughput signal (up to 7.8 Mbit s-1) even if the RTN at the input gets interrupted for long times up to 20 s, and if the stochasticity of the RTN signal is reduced. Our study presents the first full hardware implementation of 2D-material-based TRNGs, enabled by the unique stability and figures of merit of the RTN signals in h-BN based memristors.

12.
Forensic Sci Med Pathol ; 19(4): 541-550, 2023 12.
Article in English | MEDLINE | ID: mdl-36705884

ABSTRACT

Arterial gas embolism following pulmonary barotrauma occurs in 13-24% of cases of diving deaths. The study aimed to evaluate the usefulness of a histomorphometric digital analysis in the detection of air space over-distension due to pulmonary barotrauma. The study was performed on lung parenchyma specimens of 12 divers: six had died due to arterial gas embolism following pulmonary barotrauma (mean age at death of 54 years, range of 41-61 years), and six had drowned in saltwater without a diagnosis of pulmonary barotrauma (mean age at death of 54 years, range of 41-66 years) (positive controls). For negative controls, six cases of non-SCUBA divers (mean age of death of 42 years, range of 23-55 years) who died of intracerebral haemorrhage were evaluated. No significant differences were observed in the characteristics of the air spaces between control groups (positive and negative). However, differences were observed in the area occupied by air spaces and the percentage of air space area when we compared the case group to the controls (p < 0.01); and there was a slight difference in the maximum and minimum diameters of air space (p < 0.05). The mean area occupied by air spaces and the mean percentage of air space were the most useful for discriminating pulmonary barotrauma from other causes of death (100% sensitivity and 91.7% specificity). Based on our study, inclusion of an increased pattern of air spaces as a possible diagnostic criterion for pulmonary barotrauma would be useful in discerning the cause of diving death.


Subject(s)
Barotrauma , Diving , Drowning , Embolism, Air , Lung Injury , Humans , Young Adult , Adult , Middle Aged , Aged , Diving/adverse effects , Embolism, Air/pathology
13.
Micromachines (Basel) ; 13(11)2022 Nov 17.
Article in English | MEDLINE | ID: mdl-36422434

ABSTRACT

In this paper, the use of Artificial Neural Networks (ANNs) in the form of Convolutional Neural Networks (AlexNET) for the fast and energy-efficient fitting of the Dynamic Memdiode Model (DMM) to the conduction characteristics of bipolar-type resistive switching (RS) devices is investigated. Despite an initial computationally intensive training phase the ANNs allow obtaining a mapping between the experimental Current-Voltage (I-V) curve and the corresponding DMM parameters without incurring a costly iterative process as typically considered in error minimization-based optimization algorithms. In order to demonstrate the fitting capabilities of the proposed approach, a complete set of I-Vs obtained from Y2O3-based RRAM devices, fabricated with different oxidation conditions and measured with different current compliances, is considered. In this way, in addition to the intrinsic RS variability, extrinsic variation is achieved by means of external factors (oxygen content and damage control during the set process). We show that the reported method provides a significant reduction of the fitting time (one order of magnitude), especially in the case of large data sets. This issue is crucial when the extraction of the model parameters and their statistical characterization are required.

14.
Adv Mater ; 34(20): e2201197, 2022 May.
Article in English | MEDLINE | ID: mdl-35320590

ABSTRACT

The development of memristors operating at low switching voltages <50 mV can be very useful to avoid signal amplification in many types of circuits, such as those used in bioelectronic applications to interact with neurons and nerves. Here, it is reported that 400 nm-thick films made of dalkyl-dithiophosphoric (DDP) modified copper nanoparticles (CuNPs) exhibit volatile threshold-type resistive switching (RS) at ultralow switching voltage of ≈4 mV. The RS is observed in small nanocells with a lateral size of <50 nm-2 , during hundreds of cycles, and with an ultralow variability. Atomistic calculations reveal that the switching mechanism is related to the modification of the Schottky barriers and insulator-to-metal transition when ionic movement is induced via external bias. The devices are also used to model integrate-and-fire neurons for spiking neural networks and it is concluded that circuits employing DDP-CuNPs consume around ten times less power than similar neurons implemented with a memristor that switches at 40 mV.


Subject(s)
Copper , Nanoparticles , Metals , Neural Networks, Computer , Neurons
15.
Micromachines (Basel) ; 13(2)2022 Feb 19.
Article in English | MEDLINE | ID: mdl-35208454

ABSTRACT

This paper reports the fundamentals and the SPICE implementation of the Dynamic Memdiode Model (DMM) for the conduction characteristics of bipolar-type resistive switching (RS) devices. Following Prof. Chua's memristive devices theory, the memdiode model comprises two equations, one for the electron transport based on a heuristic extension of the quantum point-contact model for filamentary conduction in thin dielectrics and a second equation for the internal memory state related to the reversible displacement of atomic species within the oxide film. The DMM represents a breakthrough with respect to the previous Quasi-static Memdiode Model (QMM) since it describes the memory state of the device as a balance equation incorporating both the snapback and snapforward effects, features of utmost importance for the accurate and realistic simulation of the RS phenomenon. The DMM allows simple setting of the initial memory condition as well as decoupled modeling of the set and reset transitions. The model equations are implemented in the LTSpice simulator using an equivalent circuital approach with behavioral components and sources. The practical details of the model implementation and its modes of use are also discussed.

16.
Mol Ecol ; 31(8): 2223-2241, 2022 04.
Article in English | MEDLINE | ID: mdl-35146819

ABSTRACT

Heterogeneous seascapes and strong environmental gradients in coastal waters are expected to influence adaptive divergence, particularly in species with large population sizes where selection is expected to be highly efficient. However, these influences might also extend to species characterized by strong social structure, natal philopatry and small home ranges. We implemented a seascape genomic study to test this hypothesis in Indo-Pacific bottlenose dolphins (Tursiops aduncus) distributed along the environmentally heterogeneous coast of southern Australia. The data sets included oceanographic and environmental variables thought to be good predictors of local adaptation in dolphins and 8081 filtered single nucleotide polymorphisms (SNPs) genotyped for individuals sampled from seven different bioregions. From a neutral perspective, population structure and connectivity of the dolphins were generally influenced by habitat type and social structuring. Genotype-environment association analysis identified 241 candidate adaptive loci and revealed that sea surface temperature and salinity gradients influenced adaptive divergence in these animals at both large- (1000 km) and fine-scales (<100 km). Enrichment analysis and annotation of candidate genes revealed functions related to sodium-activated ion transport, kidney development, adipogenesis and thermogenesis. The findings of spatial adaptive divergence and inferences of putative physiological adaptations challenge previous suggestions that marine megafauna is most likely to be affected by environmental and climatic changes via indirect, trophic effects. Our work contributes to conservation management of coastal bottlenose dolphins subjected to anthropogenic disturbance and to efforts of clarifying how seascape heterogeneity influences adaptive diversity and evolution in small cetaceans.


Subject(s)
Bottle-Nosed Dolphin , Animals , Bottle-Nosed Dolphin/genetics , Ecosystem , Genomics , Salinity , Temperature
17.
Rev. Investig. Innov. Cienc. Salud ; 4(1): 26-42, 2022. tab, ilus
Article in Spanish | LILACS, COLNAL | ID: biblio-1391356

ABSTRACT

Introducción. Los docentes son usuarios ocupacionales de la voz con alto riesgo de desarrollar patologías vocales a causa de su labor. Para enfrentar esta proble-mática, suelen usarse ejercicios con tracto vocal semiocluido (TVSO), estrategia de educación/rehabilitación empleada para generar un cambio en el patrón de vibración de los pliegues vocales, minimizando el riesgo de lesión vocal al reducir el estrés de colisión al que se someten los tejidos. Diversos reportes han indicado que este tratamiento tiene efectos en el cociente de cierre (CQ), medida indirecta del estrés de colisión.Objetivo. Examinar el efecto fisiológico de dos ejercicios con TVSO en la actividad laríngea de profesores con esfuerzo vocal constante pero sin patología vocal. Metodología. Se registraron muestras de 43 profesores antes, durante y después de la realización de dos ejercicios con TVSO (vibración lingual y fonación en tubos). Las muestras de electroglotografía se analizaron para obtener el CQ. Resultados y conclusión. Se observó una diferencia significativa al comparar los valores del CQ antes y durante la realización de ambos ejercicios. No se encontraron cambios en este parámetro después de ejecutar la actividad. Estos hallazgos concuer-dan con reportes previos en los cuales el CQ tiende a aumentar durante la fonación en tubos; contrariamente, la realización de la vibración lingual tiende a decrecer el valor del CQ. Es posible que este comportamiento se deba a los mecanismos biome-cánicos particulares de cada ejercicio


Introduction. Teachers are occupational voice users with high risk of developing vocal pathologies due to their work. To face this situation, it is common the use of semi-occluded vocal tract (SOVT) exercises, a strategy of voice education/rehabil-itation implemented to induce a change in the vibration pattern of the vocal folds, mitigating, therefore, the risk of vocal lesion by reducing the collision stress applied to tissues. A variety of reports have indicated that this treatment has effects in the closed quotient (CQ), an indirect measure of collision stress. Aim. The purpose of this study was to examine the physiological effect of two dif-ferent SOVT exercises in larynx activity of teachers with constant vocal effort but without vocal pathology. Methods. 43 samples of teachers were recorded before, during and after executing two SOVT exercises (tongue trill and tube phonation). Electroglottographic samples were analyzed in order to obtain CQ. Results and conclusion. Both exercises had a significant difference of CQ scores when before and during conditions were compared. Any difference was found on this parameter after executing the activity. These findings agree with previous reports where CQ tends to increase during phonation through resonance tubes; on the con-trary, execution of tongue trill tends to decrease CQ values. This behavior might be because of the particular biomechanical mechanisms of each exercise


Subject(s)
Humans , Phonation , Speech Therapy , Voice/physiology , Respiratory System/pathology , Vocal Cords , Exercise , Education , Laryngeal Mucosa , Larynx
18.
ACS Nano ; 15(11): 17214-17231, 2021 Nov 23.
Article in English | MEDLINE | ID: mdl-34730935

ABSTRACT

Resistive switching (RS) devices are emerging electronic components that could have applications in multiple types of integrated circuits, including electronic memories, true random number generators, radiofrequency switches, neuromorphic vision sensors, and artificial neural networks. The main factor hindering the massive employment of RS devices in commercial circuits is related to variability and reliability issues, which are usually evaluated through switching endurance tests. However, we note that most studies that claimed high endurances >106 cycles were based on resistance versus cycle plots that contain very few data points (in many cases even <20), and which are collected in only one device. We recommend not to use such a characterization method because it is highly inaccurate and unreliable (i.e., it cannot reliably demonstrate that the device effectively switches in every cycle and it ignores cycle-to-cycle and device-to-device variability). This has created a blurry vision of the real performance of RS devices and in many cases has exaggerated their potential. This article proposes and describes a method for the correct characterization of switching endurance in RS devices; this method aims to construct endurance plots showing one data point per cycle and resistive state and combine data from multiple devices. Adopting this recommended method should result in more reliable literature in the field of RS technologies, which should accelerate their integration in commercial products.

19.
Insuf. card ; 16(2): 52-59, jun. 2021. ilus, tab
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1340000

ABSTRACT

La enfermedad de Chagas es una enfermedad parasitaria (Trypanosoma cruzi), endémica en 21 países de América y que las migraciones la han dispersado en distintos continentes. Una de las manifestaciones más precoces de esta enfermedad son las alteraciones disautonómicas o disfunción autonómica. La severidad de este inadecuado funcionamiento del sistema nervioso autónomo resulta mensurable, de modo que la evolución y/o progresión de la enfermedad puede constatarse mediante la alteración de estudios clínicos y detección de anticuerpos antimuscarínicos. Estos anticuerpos están presentes en un 30% de los infectados y aparecen muy precozmente una vez instalada la parasitosis; además otros estudios, como la dispersión del QT (>65 mseg) y la variabilidad de la frecuencia cardíaca (<100 mseg) presentan valores anormales. La utilización de nuevos paradigmas de atención, diagnóstico y tratamientos adecuados son imprescindibles para prevenir el desarrollo de esta cardiopatía.


Chagas disease is a parasitic disease (Trypanosoma cruzi), endemic in 21 countries of America and that migrations have dispersed it in different continents. One of the earliest manifestations of this disease is dysautonomic alterations or autonomic dysfunction. The severity of this inadequate functioning of the autonomic nervous system is measurable, so that the evolution and/or progression of the disease can be verified by altering clinical studies and detecting antimuscarinic antibodies. These antibodies are present in 30% of those infected and appear very early once the parasitosis is installed; In addition, other studies, such as QT dispersion (> 65 ms) and heart rate variability (<100 ms) show abnormal values. The use of new paradigms of care, diagnosis and appropriate treatments are essential to prevent the development of this heart disease.


A doença de Chagas é uma doença parasitária (Trypanosoma cruzi), endêmica em 21 países da América e que as migrações a dispersaram em diferentes continentes. Uma das primeiras manifestações desta doença são as alterações disautonômicas ou disfunção autonômica. A gravidade desse funcionamento inadequado do sistema nervoso autônomo é mensurável, de modo que a evolução e/ou progressão da doença pode ser verificada alterando os estudos clínicos e detectando anticorpos antimuscarínicos. Esses anticorpos estão presentes em 30% dos infectados e aparecem muito cedo, uma vez instalada a parasitose; Além disso, outros estudos, como a dispersão do QT (> 65 mseg) e a variabilidade da freqüência cardíaca (<100 mseg), mostram valores anormais. A utilização de novos paradigmas de atendimento, diagnóstico e tratamentos adequados são essenciais para prevenir o desenvolvimento desta doença cardíaca.

20.
Rev. esp. med. legal ; 47(1): 35-40, ene.-mar. 2021.
Article in Spanish | IBECS | ID: ibc-202351

ABSTRACT

El buceo es una de las actividades subacuáticas más practicadas en el litoral español. Los sistemas más comunes utilizados son el buceo con escafandra autónoma con circuito abierto, cerrado o semicerrado. Aunque hoy en día el buceo con escafandra autónoma se considera una práctica segura, cada año se describen nuevas muertes relacionadas con esta actividad. El ahogamiento es la principal causa de muerte, pero se han descrito otras, como la embolia gaseosa arterial, la enfermedad por descompresión, la enfermedad natural asociada y los traumatismos. Las autopsias de muertes relacionadas con el buceo son un gran desafío para cualquier patólogo forense, y es aconsejable poseer conocimientos sobre fisiopatología del buceo y experiencia en la práctica de técnicas de autopsia específicas. Colaborar con un equipo multidisciplinar proporciona información, evidencias y hallazgos patológicos suficientes para una investigación altamente calificada de los casos y poder resolver las principales cuestiones médico-legales


Diving is one of the most practiced underwater activities on the Spanish coast. The most common methods used in diving activities are SCUBA (self-contained underwater breathing apparatus), CCR (closed circuit rebreather) and SCR (semi-closed circuit rebreather). Although recreational diving is safe overall, diving accidents are potentially serious and even fatal. Despite all the precautions taken by divers, fatalities related to this activity are reported every year. Drowning is the main cause of death, but others have been described, such as arterial gas embolism, decompression sickness, natural pathology, and trauma. Autopsies of SCUBA diving-related deaths are a big challenge for any forensic pathologist. It is advisable to have some knowledge about diving physiopathology and experience in the practice of special autopsy techniques. Collaboration with a multidisciplinary team provides enough information, evidence and pathological findings for highly-qualified investigation of the incidents to be able to prevent similar incidents in the future


Subject(s)
Humans , Diving , Cause of Death , Interdisciplinary Research/methods , Autopsy/methods , Decompression Sickness/mortality , Drowning/mortality , Diagnosis, Differential
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