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1.
Psychophysiology ; 61(6): e14544, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38351668

ABSTRACT

Predictive coding framework posits that our brain continuously monitors changes in the environment and updates its predictive models, minimizing prediction errors to efficiently adapt to environmental demands. However, the underlying neurophysiological mechanisms of these predictive phenomena remain unclear. The present study aimed to explore the systemic neurophysiological correlates of predictive coding processes during passive and active auditory processing. Electroencephalography (EEG), functional near-infrared spectroscopy (fNIRS), and autonomic nervous system (ANS) measures were analyzed using an auditory pattern-based novelty oddball paradigm. A sample of 32 healthy subjects was recruited. The results showed shared slow evoked potentials between passive and active conditions that could be interpreted as automatic predictive processes of anticipation and updating, independent of conscious attentional effort. A dissociated topography of the cortical hemodynamic activity and distinctive evoked potentials upon auditory pattern violation were also found between both conditions, whereas only conscious perception leading to imperative responses was accompanied by phasic ANS responses. These results suggest a systemic-level hierarchical reallocation of predictive coding neural resources as a function of contextual demands in the face of sensory stimulation. Principal component analysis permitted to associate the variability of some of the recorded signals.


Subject(s)
Auditory Perception , Electroencephalography , Evoked Potentials, Auditory , Spectroscopy, Near-Infrared , Humans , Male , Female , Adult , Young Adult , Auditory Perception/physiology , Evoked Potentials, Auditory/physiology , Autonomic Nervous System/physiology , Cerebral Cortex/physiology , Anticipation, Psychological/physiology , Attention/physiology
2.
Brain Topogr ; 36(5): 736-749, 2023 09.
Article in English | MEDLINE | ID: mdl-37330940

ABSTRACT

This study analyses the spontaneous electroencephalogram (EEG) brain activity of 14 children diagnosed with Autism Spectrum Disorder (ASD) compared to 18 children with normal development, aged 5-11 years. (i) Power Spectral Density (PSD), (ii) variability across trials (coefficient of variation: CV), and (iii) complexity (multiscale entropy: MSE) of the brain signal analysis were computed on the resting state EEG. PSD (0.5-45 Hz) and CV were averaged over different frequency bands (low-delta, delta, theta, alpha, low-beta, high-beta and gamma). MSE were calculated with a coarse-grained procedure on 67 time scales and divided into fine, medium and coarse scales. In addition, significant neurophysiological variables were correlated with behavioral performance data (Kaufman Brief Intelligence Test (KBIT) and Autism Spectrum Quotient (AQ)). Results show increased PSD fast frequency bands (high-beta and gamma), higher variability (CV) and lower complexity (MSE) in children with ASD when compared to typically developed children. These results suggest a more variable, less complex and, probably, less adaptive neural networks with less capacity to generate optimal responses in ASD children.


Subject(s)
Autism Spectrum Disorder , Humans , Child , Electroencephalography/methods , Brain , Entropy
3.
Teach Learn Med ; 35(5): 589-600, 2023.
Article in English | MEDLINE | ID: mdl-35770421

ABSTRACT

ProblemIn the US, there are neither professional standards nor adequate formal training opportunities related to physician use of non-English languages, the most common of which is Spanish. To achieve safe, effective health care for culturally and linguistically diverse patients, the medical profession needs clear standards for physician language use and proven culture and language training models that include validated assessment of linguistic proficiency. InterventionThe authors describe the first decade of an innovative culture and language coaching program for bilingual (Spanish-English) pediatric residents, including the model's evolution and outcomes, as well as recommendations for implementing similar programs elsewhere. Over 10 years, the model has grown from a central innovation-the professional culture and language coach (CLC). The CLC provides 1:1 in-visit support and post-visit coaching to individual residents during three years of continuity clinic experience in a Spanish-language setting (Clínica Hispana de Cuidados de Salud-CHiCoS). They also provide a range of supplementary learning activities (e.g., simulations, immersion rotations, mock testing) and periodic formal assessment of language proficiency. Foundational program elements include cultural and linguistic humility, variations in language, pragmatic linguistics and trans-languaging, the inseparability of culture and language, health literacy, and a flat teaching hierarchy ("all teach, all learn"). ContextCHiCoS has been implemented continuously since 2009 in the primary care clinic of a stand-alone academic pediatric hospital in the Midwest, where pediatric residents have their continuity clinic experience over three years of residency. ImpactFifty-six residents have participated, reporting improved language skills, cultural knowledge, and ability to care for Spanish-speaking patients. Sixty-eight percent of residents not qualified bilingual upon program entry passed a validated physician language assessment by graduation. Spanish-speaking patients seen by CHiCoS residents and faculty reported higher satisfaction, trust, and communication scores than those seen in non-bilingual areas of the same clinic (p < .05 for all scores). The program increased bilingual faculty six-fold and changed attitudes and practices related to language supports throughout the residency program. Lessons LearnedCulture and language coaching provides effective preparation and assessment of bilingual physicians, leading to improved care for culturally and linguistically diverse patients. Our model offers an example for developing similar approaches for a variety of clinicians throughout health care. Such approaches should include professional standards for non-English language use, training supports customized to bilingual learners' proficiency levels, and a focus on integrating practical cultural and linguistic skills to achieve safe, effective clinical communication.


Subject(s)
Internship and Residency , Mentoring , Multilingualism , Physicians , Humans , Child , Language , Learning
4.
Trop Anim Health Prod ; 55(5): 297, 2023 Sep 19.
Article in English | MEDLINE | ID: mdl-37723380

ABSTRACT

Charolais is one of the most important beef cattle breeds in the world. In Mexico, it was introduced almost a century ago, and it has been suggested that particular breeding management and genetic material origin have caused a process of divergence among the current population. By a high-density SNP array genome-wide analysis, this study aimed to assess the proposed differentiation and population structure of local populations by genetic distances and structure approaches, and a European Charolais sample was included as a reference population. The differentiation statistics indicated that local populations exhibit moderate divergence, confirming a significant differentiation process between northeastern and northwestern Charolais populations (Fst≥ 0.043, D≥ 0.031). These results were strongly supported by PCA and structure analysis. Genetic isolation and low genetic flow between populations and divergent origins of introduced genetic material (i.e., semen) are likely the main drivers of the outcomes. Some implications are discussed.


Subject(s)
Body Fluids , Animals , Cattle/genetics , Mexico , Semen
5.
J Neurophysiol ; 127(5): 1240-1252, 2022 05 01.
Article in English | MEDLINE | ID: mdl-35389770

ABSTRACT

Predictive coding reflects the ability of the human brain to extract environmental patterns in order to reformulate previous expectations. The present report analyzes through the late N1 auditory component and the postimperative negative variation (PINV) the updating of predictions regarding the characteristics of a new trial, depending on the previous trial history, complexity, and type of trial (standard or deviant). Data were obtained from 31 healthy subjects recorded in a previous study based on two paradigms composed of stimulus sequences of decreasing or increasing frequencies intermingled with the sporadic appearance of unexpected tone endings. Our results showed a higher amplitude for the most complex condition and deviant trials for both the late N1 and PINV components. Additionally, the N1 and PINV presented a different amplitude response to the standard and deviant trials as a function of previous trial history, suggesting a continuous updating of trial categorization. The results suggest that the late N1 and PINV components are involved in the generation of an internal model about the rules of external auditory stimulation.NEW & NOTEWORTHY The present study showed a higher amplitude for the late N1 and the PINV with reference to both the prediction performed in auditory paradigms of higher abstraction and the unexpected breaking of the extracted rules. Additionally, both components were modulated depending on the local probability, which would suggest that they are continuously being updated by the previous stimulus history.


Subject(s)
Electroencephalography , Evoked Potentials, Auditory , Acoustic Stimulation/methods , Brain , Electroencephalography/methods , Evoked Potentials, Auditory/physiology , Humans
6.
Anim Biotechnol ; 33(6): 1086-1094, 2022 Nov.
Article in English | MEDLINE | ID: mdl-33428515

ABSTRACT

The insulin-like growth factor-1 (IGF-1), a key hormone in muscle development was investigated for single-nucleotide polymorphisms (SNPs) upstream of the IGF-1 gene and their effects upon its cognate mRNA and hormone levels in sheep. A 70 d feeding trial was conducted with 22 F1 (Dorper × Pelibuey) lambs, individually allocated and fed a diet with a forage-to-concentrate ratio of 36:64 and 17% crude protein. Sequence analyses of 265 bp upstream the IGF-1 gene revealed the variant NC_040254.1:g.[184028491G > C;184028493G > A]. These SNPs generate alleles A and B, with frequencies of 0.66 and 0.34 in F1 lambs and of 0.73 and 0.27 in 81 pure Dorper lambs, respectively. Females were grouped by genotype AA, AB and BB (n = 3). IGF-1 hormone concentrations at 14, 42 and 70 d were higher (p < 0.05) in AA lambs compared to AB + BB lambs. The IGF-1 mRNA level was 2.6-fold higher in AA animals (n = 5, p < 0.05) than in AB + BB lambs (n = 7). A DNA binding site for the Inhibitor of Growth family member 4 (ING4) was found in allele B but not in allele A, which could explain the lower mRNA and hormone expression levels for AB + BB animals. The variant reported here appears to function as an eQTL with a negative effect on the level of IGF-1.


Subject(s)
Diet , Insulin-Like Growth Factor I , Female , Sheep/genetics , Animals , Insulin-Like Growth Factor I/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , Alleles , Diet/veterinary , Hormones
7.
Sensors (Basel) ; 22(6)2022 Mar 16.
Article in English | MEDLINE | ID: mdl-35336479

ABSTRACT

This paper presents the new cable delay measurement system (CDMS) designed at Yebes Observatory (IGN, Spain), which is required for the VLBI Global Observing System (VGOS) stations. This system measures the phase difference between the 5 MHz reference signal from the hydrogen maser and the 5 MHz signal that reaches the broadband receiver through a coaxial cable, for the generation of calibration tones. As a result, the system detects the changes in the length of that coaxial cable due to temperature variations along the cable run and flexures caused by VGOS radio telescope movements. This CDMS outperforms the previous versions: firstly, it does not require a frequency counter for phase/delay measurements; secondly, it largely reduces the use of digital circuits; hence, reducing digital noise; and thirdly, it has a remotely controlled automatic calibration subsystem. The system was tested in the laboratory and in the radio telescope, and the measurements of both set-ups are shown. These measurements include the total noise, accuracy, hysteresis, and stability. The results in the radio telescope can be correlated with the different factors that affect the cable, such as temperature and flexures. The system allows to achieve an RMS noise of less than 0.5 ps, significantly improving the requirements established in VGOS. The system is currently installed in the Red Atlántica de Estaciones Geodinámicas y Espaciales (RAEGE)Yebes VGOS 13.2 m radio telescope, and will be installed in the Norwegian Mapping Authority (NMA) twin VGOS radio telescopes, in the Finnish Geospatial Research Institute (FGI) VGOS station and in the RAEGE Santa María VGOS radio telescope (Açores, Portugal).

8.
Molecules ; 27(12)2022 Jun 08.
Article in English | MEDLINE | ID: mdl-35744802

ABSTRACT

Intramolecular charge transfer (ICT) effects are responsible for the photoluminescent properties of coumarins. Hence, optical properties with different applications can be obtained by ICT modulation. Herein, four 3-acetyl-2H-chromen-2-ones (1a-d) and their corresponding fluorescent hybrids 3- (phenylhydrazone)-chromen-2-ones (2a-d) were synthesized in 74-65% yields. The UV-Vis data were in the 295-428 nm range. The emission depends on the substituent in position C-7 bearing electron-donating groups. Compounds 1b-d showed good optical properties due to the D-π-A structural arrangement. In compounds 2a-d, there is a quenching effect of fluorescence in solution. However, in the solid, an increase is shown due to an aggregation-induced emission (AIE) effect given by the rotational restraints and stacking in the crystal. Computational calculations of the HOMO-LUMO orbitals indicate high absorbance and emission values of the molecules, and gap values represent the bathochromic effect and the electronic efficiency of the compounds. Compounds 1a-d and 2a-d are good candidates for optical applications, such as OLEDs, organic solar cells, or fluorescence markers.


Subject(s)
Coumarins , Electrons , Coumarins/chemistry , Density Functional Theory , Spectrometry, Fluorescence
9.
Exp Physiol ; 106(4): 1072-1098, 2021 04.
Article in English | MEDLINE | ID: mdl-33624899

ABSTRACT

NEW FINDINGS: What is the central question of this study? Auditory stimulation produces a response in different physiological systems: cardiac, peripheral blood flow, electrodermal, cortical and peripheral haemodynamic responses and auditory event-related potentials. Do all these subsystems covary when responding to auditory stimulation, suggesting a unified locus of control, or do they not covary, suggesting independent loci of control for these physiological responses? What is the main finding and its importance? Auditory sensory gating reached a fixed level of neural activity independently of the intensity of auditory stimulation. The use of multivariate techniques revealed the presence of different regulatory mechanisms for the different physiologically recorded signals. ABSTRACT: We studied the effects of an increasing amplitude of auditory stimulation on a variety of autonomic and CNS responses and their possible interdependence. The subjects were stimulated with an increasing amplitude of auditory tones while the auditory event-related potentials (ERPs), the cortical and extracerebral functional near-infrared spectroscopy (fNIRS) signal of standard and short separation channel recordings, the peripheral pulse measured by photoplethysmography, heart rate and electrodermal responses were recorded. Trials with eight tones of equal amplitude were presented. The results showed a parallel increase of activity in ERPs, fNIRS and peripheral responses with the increase in intensity of auditory stimulation. The ERPs, measured as peak-to-peak N1-P2, showed an increase in amplitude with auditory stimulation and a high attenuation from the first presentation with respect to the second to eighth presentations. Peripheral signals and standard and short channel fNIRS responses showed a decrease in amplitude in the high-intensity auditory stimulation conditions. Principal components analysis showed independent sources of variance for the recorded signals, suggesting independent control of the recorded physiological responses. The present results suggest a complex response associated to the increase of auditory stimulation with a fixed amplitude for ERPs, and a decrease in the peripheral and cortical haemodynamic response, possibly mediated by activation of the sympathetic nervous system, constituting a defensive reflex to excessive auditory stimulation.


Subject(s)
Electroencephalography , Evoked Potentials, Auditory , Acoustic Stimulation , Autonomic Nervous System/physiology , Electroencephalography/methods , Evoked Potentials, Auditory/physiology , Humans , Multivariate Analysis
10.
Sensors (Basel) ; 21(8)2021 Apr 10.
Article in English | MEDLINE | ID: mdl-33920073

ABSTRACT

This paper shows a simultaneous tri-band (S: 2.2-2.7 GHz, X: 7.5-9 GHz and Ka: 28-33 GHz) low-noise cryogenic receiver for geodetic Very Long Baseline Interferometry (geo-VLBI) which has been developed at Yebes Observatory laboratories in Spain. A special feature is that the whole receiver front-end is fully coolable down to cryogenic temperatures to minimize receiver noise. It was installed in the first radio telescope of the Red Atlántica de Estaciones Geodinámicas y Espaciales (RAEGE) project, which is located in Yebes Observatory, in the frame of the VLBI Global Observing System (VGOS). After this, the receiver was borrowed by the Norwegian Mapping Autorithy (NMA) for the commissioning of two VGOS radiotelescopes in Svalbard (Norway). A second identical receiver was built for the Ishioka VGOS station of the Geospatial Information Authority (GSI) of Japan, and a third one for the second RAEGE VGOS station, located in Santa María (Açores Archipelago, Portugal). The average receiver noise temperatures are 21, 23, and 25 Kelvin and the measured antenna efficiencies are 70%, 75%, and 60% in S-band, X-band, and Ka-band, respectively.

11.
Entropy (Basel) ; 23(3)2021 Mar 15.
Article in English | MEDLINE | ID: mdl-33804068

ABSTRACT

The auditory mismatch negativity (MMN) has been considered a preattentive index of auditory processing and/or a signature of prediction error computation. This study tries to demonstrate the presence of an MMN to deviant trials included in complex auditory stimuli sequences, and its possible relationship to predictive coding. Additionally, the transfer of information between trials is expected to be represented by stimulus-preceding negativity (SPN), which would possibly fit the predictive coding framework. To accomplish these objectives, the EEG of 31 subjects was recorded during an auditory paradigm in which trials composed of stimulus sequences with increasing or decreasing frequencies were intermingled with deviant trials presenting an unexpected ending. Our results showed the presence of an MMN in response to deviant trials. An SPN appeared during the intertrial interval and its amplitude was reduced in response to deviant trials. The presence of an MMN in complex sequences of sounds and the generation of an SPN component, with different amplitudes in deviant and standard trials, would support the predictive coding framework.

12.
Inf Fusion ; 64: 149-187, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32834795

ABSTRACT

Multimodal fusion in neuroimaging combines data from multiple imaging modalities to overcome the fundamental limitations of individual modalities. Neuroimaging fusion can achieve higher temporal and spatial resolution, enhance contrast, correct imaging distortions, and bridge physiological and cognitive information. In this study, we analyzed over 450 references from PubMed, Google Scholar, IEEE, ScienceDirect, Web of Science, and various sources published from 1978 to 2020. We provide a review that encompasses (1) an overview of current challenges in multimodal fusion (2) the current medical applications of fusion for specific neurological diseases, (3) strengths and limitations of available imaging modalities, (4) fundamental fusion rules, (5) fusion quality assessment methods, and (6) the applications of fusion for atlas-based segmentation and quantification. Overall, multimodal fusion shows significant benefits in clinical diagnosis and neuroscience research. Widespread education and further research amongst engineers, researchers and clinicians will benefit the field of multimodal neuroimaging.

13.
Build Environ ; 185: 107265, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32939104

ABSTRACT

In this research paper, an analysis is developed on the performance of a hybrid ventilation system that combines Earth-to-Air Heat eXchangers (EAHX), free cooling and evaporative cooling Air Handling Unit Heat eXchanger (AHU-HX), all being controlled by a Building Management System (BMS) in a net Zero Energy Building (nZEB), called LUCIA. LUCIA nZEB is the first safe-building against Covid-19 in the world, certified by the international organisation WOSHIE, and located in Valladolid, Spain. The main aim is to optimize the performance of the three systems in such a way that the Indoor Air Quality (IAQ) levels remain within the allowable limits, while maximizing the use of natural resources and minimizing energy consumption and carbon emissions. The approach to satisfy the heating and cooling demand and IAQ levels through zero emissions energy systems is developed, thus anticipating the zero-energy target, set by the European Union for 2050. Results showed that the installed hybrid ventilation system uses heat exchangers for 70% of the operational time, in order to achieve the set parameters successfully. Also, the analysis made by monitoring data, have shown that the control and optimal operation of the hybrid ventilation system allows high energy recovery values with minimum additional electricity consumption. Significant reduction of carbon emissions and operational costs have been achieved.

14.
Salud Publica Mex ; 60(5): 559-565, 2018.
Article in Spanish | MEDLINE | ID: mdl-30550117

ABSTRACT

OBJECTIVE: To identify challenges derived from renal insufficiency, as well as potential solutions and an agenda for action. MATERIALS AND METHODS: y adopting a collaborative research approach, diverse stakeholders -sick people, family members, advocacy groups, health professionals, and academics- participated in two gatherings in the context of the World Kidney Day in Guadalajara, Mexico and created an agenda for action. Data was gathered through group discussions. RESULTS: Two main issues are faced by kidney sick people and their family members: the first one related with health services and, second, the lack of economic resources to pay for renal treatment. The agenda for action included rallying on public squares, installing day of the dead altars, video making, and publishing a book. CONCLUSIONS: Participation of diverse stakeholders is a valuable option to face challenges derived from renal insufficiency.


OBJETIVO: Identificar los obstáculos derivados de la insuficiencia renal, las alternativas de solución y el plan de acció. MATERIAL Y MÉTODOS: A partir de un modelo colaborativo, diversos actores sociales ­individuos enfermos, familiares, asociaciones civiles, profesionales de salud y académicos­participaron en dos encuentros en Guadalajara, México con motivo del Día Mundial del Riñón y elaboraron un plan de acción. La información se obtuvo mediante grupos de discusión. RESULTADOS: Los individuos enfermos y sus familias enfrentan dos problemas prioritarios: uno relacionado con los servicios de salud y el otro con la carencia de recursos para el pago de las terapias renales. El plan de acción incluyó marchas en plazas públicas, colocación de altares de muertos, elaboración de material audiovisual y publicación de un libro. CONCLUSIONES: La participación de diversos actores es una opción valiosa para enfrentar desafíos derivados de la insuficiencia renal.


Subject(s)
Renal Insufficiency, Chronic/therapy , Social Participation , Health Services Accessibility , Humans
15.
Phys Scr ; 93(5)2018 May.
Article in English | MEDLINE | ID: mdl-31866694

ABSTRACT

In the 50 years that succeeded Richard Feynman's exposition of the idea that there is "plenty of room at the bottom" for manipulating individual atoms for the synthesis and manufacturing processing of materials, the materials-by-design paradigm is being developed gradually through synergistic integration of experimental material synthesis and characterization with predictive computational modeling and optimization. This paper reviews how this paradigm creates the possibility to develop materials according to specific, rational designs from the molecular to the macroscopic scale. We discuss promising techniques in experimental small-scale material synthesis and large-scale fabrication methods to manipulate atomistic or macroscale structures, which can be designed by computational modeling. These include recombinant protein technology to produce peptides and proteins with tailored sequences encoded by recombinant DNA, self-assembly processes induced by conformational transition of proteins, additive manufacturing for designing complex structures, and qualitative and quantitative characterization of materials at different length scales. We describe important material characterization techniques using numerous methods of spectroscopy and microscopy. We detail numerous multi-scale computational modeling techniques that complements these experimental techniques: DFT at the atomistic scale; fully atomistic and coarse-grain molecular dynamics at the molecular to mesoscale; continuum modeling at the macroscale. Additionally, we present case studies that utilize experimental and computational approaches in an integrated manner to broaden our understanding of the properties of two-dimensional materials and materials based on silk and silk-elastin-like proteins.

16.
Salud Publica Mex ; 59(1): 53-58, 2017.
Article in Spanish | MEDLINE | ID: mdl-28423110

ABSTRACT

OBJECTIVE:: We aimed to explore organ donation and transplantation in Mexico from the point of view of transplantation health professionals. MATERIALS AND METHODS:: A qualitative study was carried out. Twenty six organ transplantation health professionals from seven states of Mexico participated. Semi-structured face-to-face interviews were conducted mainly in hospital settings. Critical discourse analysis was performed. RESULTS:: According to participants, living organ transplantation offers benefits for recipients as well as for donors. Several factors influence the field of transplantation negatively, among them the scarcity of resources that impedes the incorporation of new health personnel, as well as conflicts between transplantation teams with diverse health professionals and authorities. CONCLUSION:: Besides increasing economic resources, transplantation health personnel should be sensitized to find solutions in order to avoid conflicts with different health professionals. Studies on organ donation and transplants also should include other social actors' viewpoint.


Subject(s)
Attitude of Health Personnel , Organ Transplantation , Tissue and Organ Procurement , Humans , Mexico
17.
Molecules ; 22(3)2017 Mar 11.
Article in English | MEDLINE | ID: mdl-28287474

ABSTRACT

The solventless synthesis of tris(pyrazolyl)phenylmethane ligands of formula C6H5C(PzR2)3 (R = H, Me), starting from PhCCl3 and 3,5-dimethylpyrazole (PzMe2) or pyrazole (Pz) was performed. The sterically crowded C6H5C(PzMe2)3 is thermally transformed into the bis(pyrazolyl)(p-pyrazolyl)phenylmethane ligand PzMe2-C6H4CH(PzMe2)2. In this compound both PzMe2 rings are linked through the N-atom to the methine C-atom. At higher temperatures, the binding mode of PzMe2 changes from N1 to C4. All transformations occurred via quinonoid carbocation intermediates that undergo an aromatic electrophilic substitution on the 4-position of PzMe2. Reaction conditions were established to obtain five tris(pyrazolyl)phenylmethane ligands in moderate to good yields. ¹H- and 13C-NMR spectroscopy and X-ray diffraction of single crystals support the proposed structures.


Subject(s)
Alkanes/chemical synthesis , Methane/chemistry , Pyrazoles/chemical synthesis , Chemistry Techniques, Synthetic , Hot Temperature , Ligands , Models, Molecular , Molecular Structure , Organometallic Compounds/chemistry , Pyrazoles/chemistry
18.
Nurs Inq ; 24(2)2017 04.
Article in English | MEDLINE | ID: mdl-27672007

ABSTRACT

Renal replacement therapy is the indicated treatment for individuals with chronic kidney disease (CKD) to survive. However, not all sick people have access to the same treatment. This study compares renal care in two developing countries with different health systems. Specifically, it explores hemodialysis treatment from the perspective of low-income individuals. A qualitative, comparative study was performed in Brazil and Mexico. Using purposive sampling, the research was based on open-ended interviews with nineteen participants with kidney failure undergoing hemodialysis treatment in public hospitals and ten relatives. According to our results, Brazilian participants perceived hemodialysis care as satisfactory because of health personnel courtesy as well as free access to dialysis treatment, prescription drugs, hospitalization and transportation. However, they reported deficiencies in the care they were receiving due to shortages of specialists, prescription drugs, laboratory tests and transportation. Mexican participants, in contrast, highlighted the catastrophic costs of medical care because they had no free access to renal therapy, nor adequate financial resources. Our findings suggest that low-income Brazilian CKD sufferers experience renal care differently, as they are more satisfied and face less obstacles with hemodialysis compared with those of Mexico. More studies on the topic are needed.


Subject(s)
Healthcare Disparities , Kidney Failure, Chronic/therapy , Patient Satisfaction , Renal Dialysis/economics , Renal Dialysis/statistics & numerical data , Brazil , Delivery of Health Care , Developing Countries , Humans , Mexico , Poverty , Qualitative Research
19.
Phys Chem Chem Phys ; 18(8): 5938-48, 2016 Feb 17.
Article in English | MEDLINE | ID: mdl-26685751

ABSTRACT

PDMPO (2-(4-pyridyl)-5-((4-(2-dimethylaminoethylaminocarbamoyl)methoxy)phenyl)oxazole), has unique silica specific fluorescence and is used in biology to understand biosilicification. This 'silicaphilic' fluorescence is not well understood nor is the response to local environmental variables like solvent and pH. We investigated PDMPO in a range of environments: using UV-vis and fluorescence spectroscopy supported by computational data, (SPARC, molecular dynamics simulations, density functional theory calculations), dynamic light scattering and zeta potential measurements to understand the PDMPO-silica interaction. From absorption data, PDMPO exhibited a pKa of 4.20 for PDMPOH2(2+) to PDMPOH(+). Fluorescence emission measurements revealed large shifts in excited state pKa* values with different behaviour when bound to silica (pKa* of 10.4). PDMPO bound to silica particles is located in the Stern layer with the dye exhibiting pH dependent depolarising motion. In aqueous solution, PDMPO showed strong chromaticity with correlation between the maximum emission wavelength for PDMPOH(+)* and dielectric constant (4.8-80). Additional chromatic effects were attributed to changes in solvent accessible surface area. Chromatic effects were also observed for silica bound dye which allow its use as a direct probe of bulk pH over a range far in excess of what is possible for the dye alone (3-5.2). The unique combination of chromaticity and excited state dynamics allows PDMPO to monitor pH from 3 to 13 while also reporting on surface environment opening a new frontier in the quantitative understanding of (bio)silicification.

20.
Proc Natl Acad Sci U S A ; 115(28): 7174-7175, 2018 07 10.
Article in English | MEDLINE | ID: mdl-29929965

Subject(s)
Cellulose , Nanostructures
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