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1.
Psychol Trauma ; 16(Suppl 1): S72-S80, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37956030

ABSTRACT

OBJECTIVE: Experiences of direct and indirect victimization can be very common among children and adolescents of the general population and can have an important impact on their behavior. The general aim of this study was to analyze the possible association between childhood victimization and the development of antisocial behaviors during adolescence. The prevalence of child victimization and antisocial behaviors self-reported by adolescents is shown. Therefore, the individual associations between different types of childhood victimization and antisocial behaviors were explored. METHOD: The sample comprised 459 general population adolescents. Data on six types of childhood victimization were collected using the Spanish version of the Juvenile Victimization Questionnaire, and information on five types of antisocial behaviors was gathered using the short version of the Antisocial Behavior Questionnaire. RESULTS: More than 90% of the adolescents had been victimized at least once, while almost half of them had engaged in at least one type of antisocial behavior in the last 12 months. Witnessing and indirect victimization is the only type of childhood victimization associated with the antisocial behaviors analyzed. CONCLUSIONS: These results corroborate previous findings suggesting that witnessing and indirect victimization may have the same or similar impact to that of direct victimization on adolescents' social adjustment. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Subject(s)
Antisocial Personality Disorder , Crime Victims , Child , Humans , Adolescent , Antisocial Personality Disorder/epidemiology , Surveys and Questionnaires , Self Report
2.
BMC Psychol ; 11(1): 383, 2023 Nov 08.
Article in English | MEDLINE | ID: mdl-37941011

ABSTRACT

BACKGROUND: The use of social media became a daily activity for many individuals, with recreational, informational, and social purposes, to name a few. However, for some subjects, the use of these platforms may become problematic and generate functioning impairments in many life areas. Given this, the present research aimed at investigating the factor that may contribute to Social Media Addiction, by focusing on Fear of Missing Out and Family Functioning Patterns. METHODS: A sample of 303 social media users (Mage = 35.29; SD = 14.87; 65% females, 35% males) completed a survey including the Bergen Social Media Addiction Scale, Family Adaptability and Cohesion Evaluation Scales-IV, and Fear of Missing Out Scale. Data were analysed by implementing Pearson correlation and testing a mediation with the Structural Equation Model approach. RESULTS: Cohesion, flexibility, and disengagement family functioning patterns were significantly associated with the levels of social media addiction. These dimensions were inserted in the structural equation model, where the full mediation of fear of missing out in their relationship with social media addiction was shown. CONCLUSIONS: The data showed the protective effect of flexible and cohesive family functioning patterns, as well as the role of disengagement and, sequentially, fear of missing out as risk factors. These findings may provide useful indications to elaborate tailored and effective therapeutic and preventive activity.


Subject(s)
Internet Addiction Disorder , Social Media , Female , Male , Humans , Adult , Fear , Activities of Daily Living , Risk Factors
3.
Int J Mol Sci ; 24(17)2023 Aug 30.
Article in English | MEDLINE | ID: mdl-37686251

ABSTRACT

In 2009, a new European regulation came into force that forbade the use of animals in the cosmetics industry. As a result, new alternatives were sought, taking into account the new ethical considerations. The main objective of this article is to continue a line of research that aims to build a physical model of skin from a biomaterial scaffold composed of collagen, chitosan or a combination to investigate whether they offer similar behavior to human skin. Collagen, the major component in the dermis, was crosslinked with glutaraldehyde (GTA) to develop three formulations for studying some properties of the skin through rheological tests like swelling index, elasticity or water loss. In addition, this article makes a comparison with the results obtained in the previous article where the membranes were made of chitosan and tripolyphosphate (TPP). The results obtained highlight that the tri-layered membranes scaffold better than the mono-layered ones to increase the elastic modulus (G') and the permeability. Furthermore, they offer a protective effect against water loss compared to mono-layered membranes. As regards chitosan membranes, these have a higher G' modulus than collagen membranes when the degree of deacetylation (DDA) is 85%. However, collagen membranes are more elastic when the DDA of chitosan is 76%, and their linear viscoelastic limit (LVL) doubles that of chitosan membranes, both for the degree of acetylation of 76 and 85%.


Subject(s)
Chitosan , Animals , Humans , Biocompatible Materials , Acetylation , Collagen , Elastic Modulus
4.
Biomed Opt Express ; 14(5): 2260-2275, 2023 May 01.
Article in English | MEDLINE | ID: mdl-37206121

ABSTRACT

This work presents a stretchable elastomer optical fiber sensor incorporated into a belt for respiratory rate (RR) and heart rate (HR) monitoring. Different materials and shapes of prototypes designed were tested in terms of performance and the best choice was identified. The optimal sensor was tested by 10 volunteers to evaluate the performance. The proposed elastomer optical fiber sensor can achieve simultaneous measurement of RR and HR in different body positions, and also ballistocardiography (BCG) signal measurement in the lying position. The sensor has good accuracy and stability, with maximum errors of 1 bpm and 3 bpm for RR and HR, respectively, and average weighted mean absolute percentage error (MAPE) of 5.25% and root mean square error (RMSE) of 1.28 bpm. Moreover, the results of the Bland-Altman method showed good agreement of the sensor with manual counting of RR and with electrocardiogram (ECG) measurements of HR.

5.
Appl Opt ; 61(5): 1183-1193, 2022 Feb 10.
Article in English | MEDLINE | ID: mdl-35201171

ABSTRACT

We propose a stable full-duplex transmission of millimeter-wave signals over a hybrid single-mode fiber (SMF) and free-space optics (FSO) link for the fifth-generation (5G) radio access networks to accelerate the Industry 4.0 transformation. For the downlink (DL), we transmit 39 GHz subcarrier multiplexing (SCM) signals using variable quadrature amplitude modulation (QAM) allocations for multi-user services. As a proof of operation, we experimentally demonstrate the transmission of 3 Gb/s SCM signals (1 Gb/s per user) over a hybrid system consisting of a 10 km SMF and 1.2 m FSO link. For the uplink (UL), satisfactory performance for the transmission of 2.4 Gb/s 5G new radio (NR) signal at 37 GHz over the hybrid system is experimentally confirmed for the first time, to the best of our knowledge. The measured error vector magnitudes for both DL and UL signals using 4/16/64-QAM formats are well below the third generation partnership project (3GPP) requirements. We also further evaluate by simulation the full-duplex transmission over the system in terms of received optical and RF powers and bit error rate performance. A wireless radio distance of approximately 200 m, which is sufficient for 5G small-cell networks, is estimated for both DL and UL direction under the heavy rain condition, based on the available data from Spain. Furthermore, simulation for the DL direction is conducted to verify the superior performance of the system using variable QAM allocation over uniform QAM allocation. Using a variable modulation allocation, up to five users (2 Gb/s per user) can be transmitted over a hybrid 10 km SMF and 150 m FSO link.

6.
Rev. Rol enferm ; 45(1): 16-24, Ene. 2022. ilus, tab
Article in Spanish | IBECS | ID: ibc-207199

ABSTRACT

El virus SARS-CoV-2 llevó a la puesta en marcha de medidas de aislamiento extremas en pa-cientes hospitalizados, con la consecuente prohibición de visitas de familiares, y de la libre circulación del personal no sanitario dentro del hospital. La hospitalización como entrada a un lugar extraño y hostil, puede generar diferentes sensaciones en los pacientes, entre ellas temor e incertidumbre. El presente trabajo describe el desarrollo e implementación de un programa asistencial para responder la necesidad de comunicación entre pacientes y fami-liares, durante su ingreso hospitalario por COVID-19. El programa se estructuró en tres fases (pre-llamada, llamada/videollamada y post-llamada). Se realizaron 451 intervenciones. La mayor demanda de intervención para comunicación fue procedente de salas de hospitali-zación convencional con un 56,74% y un 43,25% de salas de críticos. El programa puso de manifiesto situaciones relacionadas con la hospitalización y el aisla-miento; rápidamente se activó un programa para humanizar el proceso asistencial durante la pandemia por COVID-19 y mantener el contacto de pacientes y familiares de utilizando las nuevas tecnologías de la comunicación. (AU)


The SARS-CoV-2 virus led to the implementation of extreme isolation measures in hospi-talized patients, with the consequent prohibition of family visits, and the f ree movement of non-health personnel within the hospital. Hospitalization as an entrance to a strange and hostile place could generate different emotions in patients, including fear and un-certainty. This article describes the development and implementation of a program to respond to the need for communication between patients and their families, during their hospitalization due to COVID-19. The program was structured in three phases (pre-call, call/video call and post-call). 451 interventions were carried out. The highest demand for intervention for communication came f rom conventional hospital wards with 56.74% and 43.25% f rom critical wards.The program revealed situations related to hospitalization and isolation; A program was quickly activated to humanize the care process during the COVID-19 pandemic and maintain contact with patients and families using new communication technologies. (AU)


Subject(s)
Humans , Young Adult , Adult , Middle Aged , Aged , Aged, 80 and over , Pandemics , Coronavirus Infections/epidemiology , Severe acute respiratory syndrome-related coronavirus , Quarantine , Communication , Cross-Sectional Studies , Epidemiology, Descriptive , Videoconferencing
7.
Rev. latinoam. cienc. soc. niñez juv ; 19(2): 103-121, mayo-ago. 2021. tab, graf
Article in Spanish | LILACS | ID: biblio-1347579

ABSTRACT

Resumen (Analítico) La salud mental de los niños, niñas y adolescentes institucionalizados en hogares es un desafío clínico y ético para Chile y América Latina. Con el objetivo de explorar experiencias y desafíos percibidos por profesionales de la atención primaria de salud que atienden esta población, se realizó una investigación cualitativa, utilizando un cuestionario con preguntas abiertas. Los datos se analizaron mediante teoría fundamentada. Los resultados mostraron que la atención era parcializada y discontinua. La información sobre el desarrollo vital, la familia, los contextos de vulneración e institucionalización era insuficiente y fragmentada. Además, existía escasa coordinación entre las instituciones que intervienen simultáneamente con los niños, niñas y adolescentes. Se discuten las implicancias para la formación de equipos de salud mental de la atención primaria de salud y la implementación efectiva del trabajo intersectorial y multinivel.


Abstract (analytical) Mental health care for vulnerable and institutionalized children and adolescents is a clinical and ethical challenge in Chile and Latin America. This study explores experiences and challenges encountered when providing mental health care among primary health care professionals. Qualitative research was conducted using an open-ended questionnaire for interviewing professionals in a rural area of Chile. The data was analyzed using Grounded Theory. The results show a fragmented and discontinuous delivery of care as a large portion of the children's clinical and social history is unknown. There is lack of coordination with other institutions that intervene in this area. The authors discuss implications for primary health care training for children's mental health teams and the need for the implementation of effective integrated and multilevel care systems.


Resumo (Analítico) A saúde mental de crianças e adolescentes vulneráveis e institucionalizados é um desafio clínico e ético no Chile e na América Latina. O presente estudo explorou experiências e desafios do cuidado por profissionais da atenção primária à saúde que atendem esta população. A pesquisa qualitativa foi realizada utilizando um questionário de perguntas abertas para entrevistar profissionais da área rural do Chile. Os dados foram analisados usando a Grounded Theory. Os resultados mostraram um atendimento fragmentado e descontínuo. As informações sobre parte da história clínica e social das crianças, e os contextos de vulnerabilidade e institucionalização são insuficientes. Além disso, existia pouca coordenação entre as instituições que intervêm simultaneamente com os crianças e adolescentes. São discutidas implicações para o treinamento de equipes de saúde mental na atenção primária à saúde e para a implementação de sistemas efetivos de atendimento integrado e multinível.


Subject(s)
Primary Health Care , Mental Health , Surveys and Questionnaires , Qualitative Research , Institutionalization
8.
Appl Opt ; 59(16): 4997-5005, 2020 Jun 01.
Article in English | MEDLINE | ID: mdl-32543497

ABSTRACT

We present a theoretical and experimental study on the impact of different thermal-induced free-space turbulence distributions on the M-quadrature amplitude modulation (M-QAM) signal transmission in radio frequency K-band over hybrid optical links of standard single mode fiber (SSMF) and free-space optics (FSO). Frequency multiplication using an external intensity modulator biased at the null transmission point has been employed to photonically generate radio signals at a frequency of 25 GHz , included for the frequency bands for fifth-generation (5G) mobile networks. Moreover, extensive simulations have been performed for 10Gb/s with 4-, 16-, and 64-QAM over 5 km of SSMF and 500 m long FSO channels under scenarios with different turbulence levels and distributions. Proof-of-concept experiments have been conducted for 20 MHz with 4- and 64-QAM over 5 km of SSMF and 2 m long FSO channels under turbulence conditions. Both theoretical and experimental systems have been analyzed in terms of error vector magnitude (EVM) performance showing feasible transmission over the hybrid links in the received optical power range. Non-uniform turbulence distributions are shown to have a different impact on M-QAM modulation formats, i.e., turbulence distributions with higher strength in the middle of the FSO link reveal a 1.9 dB penalty when using 64-QAM signals compared to a 1.3 dB penalty using 4-QAM signals, whereas higher penalties have been measured when 4-QAM format is transmitted over turbulence distributions with larger magnitude in the second half of the FSO link. The results have been validated by theoretical predictions and lead to practical consequences on future networks' deployment.

9.
Anal Chem ; 92(10): 6832-6838, 2020 05 19.
Article in English | MEDLINE | ID: mdl-32298576

ABSTRACT

Untargeted molecular analyses of complex mixtures are relevant for many fields of research, including geochemistry, pharmacology, and medicine. Ultrahigh-resolution mass spectrometry is one of the most powerful tools in this context. The availability of open scripts and online tools for specific data processing steps such as noise removal or molecular formula assignment is growing, but an integrative tool where all crucial steps are reproducibly evaluated and documented is lacking. We developed a novel, server-based tool (ICBM-OCEAN, Institute for Chemistry and Biology of the Marine Environment, Oldenburg-complex molecular mixtures, evaluation & analysis) that integrates published and novel approaches for standardized processing of ultrahigh-resolution mass spectrometry data of complex molecular mixtures. Different from published approaches, we offer diagnostic and validation tools for all relevant steps. Among other features, we included objective and reproducible reduction of noise and systematic errors, spectra recalibration and alignment, and identification of likeliest molecular formulas. With 15 chemical elements, the tool offers high flexibility in formula attribution. Alignment of mass spectra among different samples prior to molecular formula assignment improves mass error and facilitates molecular formula confirmation with the help of isotopologues. The online tool and the detailed instruction manual are freely accessible at www.icbm.de/icbm-ocean.

10.
Sci Rep ; 10(1): 809, 2020 01 21.
Article in English | MEDLINE | ID: mdl-31964928

ABSTRACT

Ecological differentiation between strains of bacterial species is shaped by genomic and metabolic variability. However, connecting genotypes to ecological niches remains a major challenge. Here, we linked bacterial geno- and phenotypes by contextualizing pangenomic, exometabolomic and physiological evidence in twelve strains of the marine bacterium Alteromonas macleodii, illuminating adaptive strategies of carbon metabolism, microbial interactions, cellular communication and iron acquisition. In A. macleodii strain MIT1002, secretion of amino acids and the unique capacity for phenol degradation may promote associations with Prochlorococcus cyanobacteria. Strain 83-1 and three novel Pacific isolates, featuring clonal genomes despite originating from distant locations, have profound abilities for algal polysaccharide utilization but without detrimental implications for Ecklonia macroalgae. Degradation of toluene and xylene, mediated via a plasmid syntenic to terrestrial Pseudomonas, was unique to strain EZ55. Benzoate degradation by strain EC673 related to a chromosomal gene cluster shared with the plasmid of A. mediterranea EC615, underlining that mobile genetic elements drive adaptations. Furthermore, we revealed strain-specific production of siderophores and homoserine lactones, with implications for nutrient acquisition and cellular communication. Phenotypic variability corresponded to different competitiveness in co-culture and geographic distribution, indicating linkages between intraspecific diversity, microbial interactions and biogeography. The finding of "ecological microdiversity" helps understanding the widespread occurrence of A. macleodii and contributes to the interpretation of bacterial niche specialization, population ecology and biogeochemical roles.


Subject(s)
Alteromonas/physiology , Adaptation, Biological , Alteromonas/metabolism , Biological Variation, Population , Ecosystem , Ecotype , Genetic Variation , Genome, Bacterial , Iron/metabolism , Pacific Ocean , Phylogeny , Plasmids , Polysaccharides/metabolism , Prochlorococcus/physiology , Seawater/microbiology , Seaweed/metabolism , Secondary Metabolism
11.
Opt Express ; 27(23): 33745-33756, 2019 Nov 11.
Article in English | MEDLINE | ID: mdl-31878436

ABSTRACT

Two experimental configurations of a hybrid K-band (25 GHz) microwave photonic link (MPL) are investigated for seamless broadband wireless access networks. Experimental configurations consist of optical fiber, free-space optics (FSO) and radio frequency (RF) wireless channels. We analyze in detail the effects of channel impairments, namely fiber chromatic dispersion, atmospheric turbulence and multipath-induced fading on the transmission performance. In the first configuration, transmission of the 64-quadrature amplitude modulation (QAM) signal with 5, 20 and 50 MHz bandwidths over 5 km standard single-mode fiber (SSMF), 2 m turbulent FSO and 3 m RF wireless channels is investigated. We show that, for QAM with a high bandwidth, the link performance is being affected more by atmospheric turbulence. In the second configuration, the 20 MHz 4/16/64-QAM signals over a 50 km SSMF and 40 m FSO/RF wireless links are successfully transmitted with the measured error vector magnitude (EVM) values of 12, 9 and 7.9%, respectively. It is shown that, for all transmitted microwave vector signals, the bit error rate is lower than the hard-decision forward-error-correction limit of 3.8×10-3. Moreover, an extended FSO link span of 500 m for 25 GHz hybrid MPL with 16-QAM at 10 Gb/s under the weak and strong turbulence regimes is evaluated via simulation analysis to mimic a practical outdoor system.

12.
Opt Express ; 27(26): 38039-38048, 2019 Dec 23.
Article in English | MEDLINE | ID: mdl-31878576

ABSTRACT

We present the first Bragg gratings fabricated in two, three and five rings undoped PMMA microstructured polymer optical fibres (mPOFs) with relative low cost 266 nm Nd:YAG laser in the 850 nm region. The fibers were connectorised with commercial ferrules for easy coupling with silica patch cables. Temperature, humidity and strain sensitivities are measured and also the impact of ring structure and the diameter of POF on the characterization measurements are studied for potential applications. We also analyzed the effect of the number of hexagonal rings structure in gratings fabrication, noticing that larger number of rings lead to more difficulties to obtain strong gratings, where we consider this performance due to the scattering effects. We demonstrate Bragg gratings fabrication in 5-rings structure mPOF after 6 min by using 266 nm Nd:YAG laser whereas no Bragg gratings have been fabricated so far using 325 nm He-Cd laser system. Up to 30 dB relative reflected power gratings are obtained in two rings mPOF, showing good time stability and promising results for undoped mPOF applications.

13.
Environ Microbiol ; 21(11): 4062-4075, 2019 11.
Article in English | MEDLINE | ID: mdl-31336026

ABSTRACT

Ammonia-oxidizing archaea (AOA) constitute a considerable fraction of microbial biomass in the global ocean, comprising 20%-40% of the ocean's prokaryotic plankton. However, it remains enigmatic to what extent these chemolithoautotrophic archaea release dissolved organic carbon (DOC). A combination of targeted and untargeted metabolomics was used to characterize the exometabolomes of three model AOA strains of the Nitrosopumilus genus. Our results indicate that marine AOA exude a suite of organic compounds with potentially varying reactivities, dominated by nitrogen-containing compounds. A significant fraction of the released dissolved organic matter (DOM) consists of labile compounds, which typically limit prokaryotic heterotrophic activity in open ocean waters, including amino acids, thymidine and B vitamins. Amino acid release rates corresponded with ammonia oxidation activity and the three Nitrosopumilus strains predominantly released hydrophobic amino acids, potentially as a result of passive diffusion. Despite the low contribution of DOC released by AOA (~0.08%-1.05%) to the heterotrophic prokaryotic carbon demand, the release of physiologically relevant metabolites could be crucial for microbes that are auxotrophic for some of these compounds, including members of the globally abundant and ubiquitous SAR11 clade.


Subject(s)
Ammonia/metabolism , Archaea/metabolism , Heterotrophic Processes/physiology , Organic Chemicals/metabolism , Carbon/metabolism , Chemoautotrophic Growth/physiology , Oceans and Seas , Oxidation-Reduction , Phylogeny
14.
Front Microbiol ; 10: 215, 2019.
Article in English | MEDLINE | ID: mdl-30837961

ABSTRACT

Marine dissolved organic matter (DOM) is a complex mixture of chemical compounds. At 750 Pg C, it is one of the biggest pools of reduced carbon on Earth. It has been proposed that the diversity of DOM is responsible for its recalcitrance. We hypothesize that the chemodiversity of marine DOM is a reflection of the chemodiversity of bacterial exometabolomes. To test this, we incubated two model strains of the Roseobacter group; Phaeobacter inhibens and Dinoroseobacter shibae in pure culture using three different simple organic compounds as sole carbon sources (glutamate, glucose, and acetate and succinate for P. inhibens and D. shibae, respectively). The exometabolome of the model organisms was characterized using Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR-MS) and ecological diversity measures. We detected thousands of molecular masses in the exometabolomes of P. inhibens and D. shibae (21,105 and 9,386, respectively), reflecting the capability of single bacterial strains to diversify simple organic compounds. The chemical composition of the exometabolomes changed with growth phase and also differed according to the strain incubated and the utilized substrate. We mimicked a higher diversity of substrates, bacterial species and heterogeneous growth (different growth phases) to approach the complexity of natural environments, by computationally creating combinations of detected exometabolomes. We compared the chemodiversity of these combinations, indicative for chemodiversity of freshly produced microbial DOM to that of refractory DOM from one of the oldest oceanic water masses (North Equatorial Pacific Intermediate Water). Some combinations of exometabolomes showed higher richness than the deep ocean refractory DOM, and all the combinations showed higher functional diversity. About 15% of the 13,509 molecular formulae detected in exometabolomes and refractory oceanic DOM were shared, i.e., occurred in Roseobacter exometabolomes and in deep water samples. This overlap provides further support for our hypothesis that marine bacteria from the Roseobacter group contribute to the sustainability of marine DOM chemodiversity and stability.

15.
ISME J ; 13(1): 92-103, 2019 01.
Article in English | MEDLINE | ID: mdl-30116038

ABSTRACT

Algal polysaccharides are an important bacterial nutrient source and central component of marine food webs. However, cellular and ecological aspects concerning the bacterial degradation of polysaccharide mixtures, as presumably abundant in natural habitats, are poorly understood. Here, we contextualize marine polysaccharide mixtures and their bacterial utilization in several ways using the model bacterium Alteromonas macleodii 83-1, which can degrade multiple algal polysaccharides and contributes to polysaccharide degradation in the oceans. Transcriptomic, proteomic and exometabolomic profiling revealed cellular adaptations of A. macleodii 83-1 when degrading a mix of laminarin, alginate and pectin. Strain 83-1 exhibited substrate prioritization driven by catabolite repression, with initial laminarin utilization followed by simultaneous alginate/pectin utilization. This biphasic phenotype coincided with pronounced shifts in gene expression, protein abundance and metabolite secretion, mainly involving CAZymes/polysaccharide utilization loci but also other functional traits. Distinct temporal changes in exometabolome composition, including the alginate/pectin-specific secretion of pyrroloquinoline quinone, suggest that substrate-dependent adaptations influence chemical interactions within the community. The ecological relevance of cellular adaptations was underlined by molecular evidence that common marine macroalgae, in particular Saccharina and Fucus, release mixtures of alginate and pectin-like rhamnogalacturonan. Moreover, CAZyme microdiversity and the genomic predisposition towards polysaccharide mixtures among Alteromonas spp. suggest polysaccharide-related traits as an ecophysiological factor, potentially relating to distinct 'carbohydrate utilization types' with different ecological strategies. Considering the substantial primary productivity of algae on global scales, these insights contribute to the understanding of bacteria-algae interactions and the remineralization of chemically diverse polysaccharide pools, a key step in marine carbon cycling.


Subject(s)
Alteromonas/physiology , Polysaccharides/metabolism , Acclimatization , Adaptation, Physiological , Alginates/metabolism , Alteromonas/genetics , Ecosystem , Proteomics
16.
Opt Lett ; 43(20): 5106-5109, 2018 Oct 15.
Article in English | MEDLINE | ID: mdl-30320831

ABSTRACT

We demonstrate a largely tunable dispersion fiber Bragg grating (FBG) inscribed in a microstructured polymer optical fiber (mPOF). The bandwidth of the chirped FBG (CFBG) was achieved from 0.11 to 4.86 nm, which corresponds to a tunable dispersion range from 513.6 to 11.15 ps/nm. Furthermore, thermal sensitivity is used to compensate for the wavelength shift due to the applied strain. These results demonstrate that a CFBG in a POF is a promising technology for future optical systems.

17.
Rev. neurol. (Ed. impr.) ; 67(6): 203-209, 16 sept., 2018. tab
Article in Spanish | IBECS | ID: ibc-175212

ABSTRACT

Introducción. Con posterioridad a la oleada del virus del Zika y el incremento en la incidencia de síndrome de Guillain-Barré (SGB), se ha estudiado la relación causal, pero no se ha encontrado una plena correlación etiológica. Pacientes y métodos. Del 1 de enero al 31 de diciembre de 2017, se incluyeron pacientes con SGB. Además de las serologías básicas, se solicitaron determinaciones de enterovirus, virus del herpes, Campylobacter, hepatitis B y C, TORCH, virus de la inmunodeficiencia humana, Brucella y Salmonella. Resultados. Cohorte de siete pacientes de sexo masculino. A cinco pacientes se les analizó el líquido cefalorraquídeo, que era normal. A todos se les realizó una tomografía encefálica, también normal, y se realizó neuroconducción, que mostró polineuropatía inflamatoria desmielinizante aguda en cuatro casos y neuropatía motora axonal aguda en uno. Todos recibieron inmunoglobulinas intravenosas; tuvieron buen pronóstico cinco casos y hubo dos defunciones. No se informó de casos positivos al virus del Zika. Hubo un caso positivo al dengue, uno al chikungunya, cinco a Campylobacter y uno a enterovirus. Se informó de coinfecciones de dengue + Campylobacter en un caso y de chikungunya + Campylobacter en otro. Conclusiones. La presente cohorte demuestra que no fue posible establecer una relación causal entre el SGB y el virus del Zika, pero se identificaron otros agentes causales víricos y bacterianos, como dengue, chikungunya y enterovirus, y fue aún más destacable la identificación de los casos de Campylobacter


Introduction. After Zika virus outbreak and the increase in the incidence of Guillain-Barré syndrome (GBS), the causal relationship has been studied, however a full etiological correlation has not been found. Patients and methods. From January 1 to December 31, 2017, patients with GBS were included. In addition to the basic serologies, enterovirus, herpes, Campylobacter, hepatitis B and C, TORCH, HIV, Brucella and Salmonella were requested Results. Cohort of seven male patients. Five patients analyzed cerebrospinal fluid reporting normal; all of them underwent brain scan, reporting normal. Neuroconduction was performed, resulting in acute inflammatory demyelinating polyneuropathy in four cases and acute motor axonal neuropathy in one case. All received intravenous immunoglobulins, five cases had a good prognosis and two deaths. No positive cases were reported to Zika virus. A positive case was reported to dengue and another to chikungunya. Five positive cases were reported to Campylobacter. One case positive to enterovirus. Dengue + Campylobacter coinfections were reported in one case and chikungunya + Campylobacter in another case. Conclusions. The present cohort shows that it was not possible to establish a causal relationship between GBS and Zika virus, but other viral and bacterial causal agents were identified, such as dengue, chikungunya and enterovirus, with the identification of Campylobacter cases even more remarkable


Subject(s)
Humans , Male , Middle Aged , Aged , Guillain-Barre Syndrome/etiology , Guillain-Barre Syndrome/epidemiology , Immunoglobulins/therapeutic use , Enterovirus Infections/complications , Guillain-Barre Syndrome/blood , Guillain-Barre Syndrome/cerebrospinal fluid , Mexico/epidemiology , Cohort Studies , Administration, Intravenous , Brain/diagnostic imaging , Arbovirus Infections/epidemiology , Prospective Studies , Cross-Sectional Studies
18.
Opt Express ; 26(14): 18096-18104, 2018 Jul 09.
Article in English | MEDLINE | ID: mdl-30114089

ABSTRACT

We experimentally demonstrate the first polymer optical fiber Bragg gratings inscribed with only one Nd:YAG laser (266 nm) pulse. The gratings have been inscribed in a single-mode poly (methyl methacrylate) optical fiber, with a core doped with benzyl dimethyl ketal for photosensitivity enhancement. One laser pulse with a duration of 8 ns and energy of 72 µJ is adequate to introduce a refractive index change of 0.5 × 10-4 in the fiber core. The stability of the gratings has been confirmed and the strain and temperature sensitivity measurements demonstrate their tunable properties.

19.
Plant Physiol ; 177(3): 896-910, 2018 07.
Article in English | MEDLINE | ID: mdl-29752308

ABSTRACT

Recent progress in root phenotyping has focused mainly on increasing throughput for genetic studies, while identifying root developmental patterns has been comparatively underexplored. We introduce a new phenotyping pipeline for producing high-quality spatiotemporal root system development data and identifying developmental patterns within these data. The SmartRoot image-analysis system and temporal and spatial statistical models were applied to two cereals, pearl millet (Pennisetum glaucum) and maize (Zea mays). Semi-Markov switching linear models were used to cluster lateral roots based on their growth rate profiles. These models revealed three types of lateral roots with similar characteristics in both species. The first type corresponds to fast and accelerating roots, the second to rapidly arrested roots, and the third to an intermediate type where roots cease elongation after a few days. These types of lateral roots were retrieved in different proportions in a maize mutant affected in auxin signaling, while the first most vigorous type was absent in maize plants exposed to severe shading. Moreover, the classification of growth rate profiles was mirrored by a ranking of anatomical traits in pearl millet. Potential dependencies in the succession of lateral root types along the primary root were then analyzed using variable-order Markov chains. The lateral root type was not influenced by the shootward neighbor root type or by the distance from this root. This random branching pattern of primary roots was remarkably conserved, despite the high variability of root systems in both species. Our phenotyping pipeline opens the door to exploring the genetic variability of lateral root developmental patterns.


Subject(s)
Image Processing, Computer-Assisted/methods , Pennisetum/growth & development , Plant Roots/anatomy & histology , Plant Roots/growth & development , Zea mays/growth & development , Indoleacetic Acids/metabolism , Markov Chains , Models, Biological , Models, Statistical , Pennisetum/anatomy & histology , Plant Roots/physiology , Zea mays/genetics
20.
Opt Express ; 26(4): 4411-4420, 2018 Feb 19.
Article in English | MEDLINE | ID: mdl-29475291

ABSTRACT

We demonstrate chirped Bragg gratings fabrication in doped microstructured tapered polymer fibers by using a uniform phase mask. The use of high photosensitive benzyl dimethyl ketal (BDK) doped core fiber allows to obtain chirped Bragg gratings by means of a single krypton fluoride laser pulse. The stability of the gratings has been confirmed and the strain and temperature sensitivity measurements demonstrate their tunable properties. Finally, different tapered profiles have been implemented in order to show the potentiality of this fabrication technique in polymer optical fibers.

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