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1.
Hortic Res ; 10(8): uhad141, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37575654

RESUMO

The development of new cultivars with improved nitrogen use efficiency (NUE) is key for implementing sustainable agriculture practices. Crop wild relatives (CWRs) provide valuable genetic resources for breeding programs aimed at achieving this goal. In this study, three eggplant (Solanum melongena) accessions together with their advanced backcrosses (ABs; BC3 to BC5 generations) were evaluated for 22 morpho-agronomic, physiological, and NUE traits under low nitrogen (LN) fertilization conditions. The ABs were developed with introgressions from the wild relatives Solanum insanum, Solanum dasyphyllum, and Solanum elaeagnifolium. The AB population comprised a total of 25, 59, and 59 genotypes, respectively, with overall donor wild relative genome coverage percentages of 58.8%, 46.3%, and 99.2%. The three S. melongena recurrent parents were also evaluated under control (normal) N fertilization. Reduction of N fertilization in the parents resulted in decreased chlorophyll content-related traits, aerial biomass, stem diameter, and yield and increased NUE, nitrogen uptake efficiency (NUpE), and nitrogen utilization efficiency (NUtE). However, the decrease in yield was moderate, ranging between 62.6% and 72.6%. A high phenotypic variation was observed within each of the three sets of ABs under LN conditions, with some individuals displaying improved transgressive characteristics over the recurrent parents. Using the single primer enrichment technology 5 k probes platform for high-throughput genotyping, we observed a variable but high degree of recurrent parent genome recovery in the ABs attributable to the lines recombination, allowing the successful identification of 16 quantitative trait loci (QTL). Different allelic effects were observed for the introgressed QTL alleles. Several candidate genes were identified in the QTL regions associated with plant growth, yield, fruit size, and NUE-related parameters. Our results show that eggplant materials with introgressions from CWRs can result in a dramatic impact in eggplant breeding for a more sustainable agriculture.

2.
Rev Gastroenterol Mex (Engl Ed) ; 87(1): 63-79, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34973937

RESUMO

INTRODUCTION: The SARS-CoV-2 virus that causes the COVID-19 disease is transmitted through the inhalation of droplets or aerosols and inoculation via the oronasal or ocular routes, transforming the management of swallowing disorders into a challenge for healthcare teams, given their proximity to the aerodigestive tract and the high probability of aerosol generation during patient evaluation and treatment. AIM: To provide essential guidance for Latin American multidisciplinary teams, regarding the evaluation and treatment of oropharyngeal and esophageal dysphagia, at the different levels of healthcare. The position statement was formulated for the purpose of maintaining medical service continuity, in the context of a pandemic, and minimizing the propagation and infection risks of the virus. METHODS: Thirteen experts in swallowing disorders were summoned by the Latin American Dysphagia Society to formulate a series of clinical suggestions, based on available evidence and clinical experience, for the management of dysphagia, taking the characteristics of Latin American healthcare systems into account. RESULTS: The position statement of the Latin American Dysphagia Society provides a series of clinical suggestions directed at the multidisciplinary teams that manage patients with oropharyngeal and esophageal dysphagia. It presents guidelines for evaluation and treatment in different contexts, from hospitalization to home care. CONCLUSIONS: The present statement should be analyzed by each team or healthcare professional, to reduce the risk for COVID-19 infection and achieve the best therapeutic results, while at the same time, being mindful of the reality of each Latin American country.


Assuntos
COVID-19 , Transtornos de Deglutição , Transtornos de Deglutição/epidemiologia , Transtornos de Deglutição/terapia , Humanos , América Latina/epidemiologia , Pandemias , SARS-CoV-2
3.
Sci Rep ; 12(1): 797, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35039503

RESUMO

A series of gallium arsenide bismide device layers covering a range of growth conditions are thoroughly probed by low-temperature, power-dependent photoluminescence measurements. The photoluminescence data is modelled using a localised state profile consisting of two Gaussians. Good agreement with the raw data is achieved for all layers whilst fixing the standard deviation values of the two Gaussians and constraining the band gap using X-ray diffraction data. The effects of growth temperature and bismuth beam equivalent pressure on the localised state distributions, and other model variables, are both shown to be linked to emission linewidth and device properties. It is concluded that bismuth rich surface conditions are preferable during growth in order to produce the narrowest emission linewidths with this material. These results also show how the growth mode of a gallium arsenide bismide layer can be inferred ex-situ from low-temperature photoluminescence measurements.

5.
Front Pediatr ; 10: 1055997, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36819199

RESUMO

Background: Developmental assessment remains an integral part of the routine evaluation of the wellbeing of every child. Children in resource-poor countries are not routinely assessed for signs of developmental delay and developmental disorders are frequently overlooked. A major gap exists in the availability of culturally appropriate and cost-effective developmental screening tools in many low and middle income countries (LMICs) with large populations. Objective: To bridge the existing gap, we describe the process of the development and validation of the Ibadan Simplified Developmental Screening (ISDS) chart, for routine developmental screening in Nigerian children. Methods: We developed an item pool across 4 domains of development namely, the gross motor, vision-fine motor, communication and socio-behavioural domains. The ISDS chart consists of 3-4 item questions for each domain of development, and responses are to be provided by the caregiver. Each chart is age-specific, from 6 weeks to 12 months. A total score derived from the summation of the scores in each domain are plotted on the ISDS scoring guide with a pass or fail score. Each child was evaluated by the Ages and Stages Questionnaire as the standard. Results: A total of 950 infants; 453 males and 497 females were enrolled. The estimates of internal consistency between the two instruments ranged between 0.7-1.0. Using the ASQ as the gold standard, the ISDS chart demonstrated a sensitivity of 98.8%, 78.4% and 99.7% in the gross motor, communication and the social and emotional domains respectively, for detecting infants who might require further assessment for developmental delays. Conclusion: The indigenous tool fills a major gap in the need for cost-effective interventions for developmental monitoring in LMICs. Future work should include the deployment of the tool in the wider population, using digital health approaches that could underpin policy making in the region.

6.
Rev Gastroenterol Mex ; 87(1): 63-79, 2022.
Artigo em Espanhol | MEDLINE | ID: mdl-34728891

RESUMO

INTRODUCTION: The SARS-CoV-2 virus that causes the COVID-19 disease is transmitted through the inhalation of droplets or aerosols and inoculation via the oronasal or ocular routes, transforming the management of swallowing disorders into a challenge for healthcare teams, given their proximity to the aerodigestive tract and the high probability of aerosol generation during patient evaluation and treatment. AIM: To provide essential guidance for Latin American multidisciplinary teams, regarding the evaluation and treatment of oropharyngeal and esophageal dysphagia, at the different levels of healthcare. The position statement was formulated for the purpose of maintaining medical service continuity, in the context of a pandemic, and minimizing the propagation and infection risks of the virus. METHODS: Thirteen experts in swallowing disorders were summoned by the Latin American Dysphagia Society to formulate a series of clinical suggestions, based on available evidence and clinical experience, for the management of dysphagia, taking the characteristics of Latin American healthcare systems into account. RESULTS: The position statement of the Latin American Dysphagia Society provides a series of clinical suggestions directed at the multidisciplinary teams that manage patients with oropharyngeal and esophageal dysphagia. It presents guidelines for evaluation and treatment in different contexts, from hospitalization to home care. CONCLUSIONS: The present statement should be analyzed by each team or healthcare professional, to reduce the risk for COVID-19 infection and achieve the best therapeutic results, while at the same time, being mindful of the reality of each Latin American country.

7.
Sci Rep ; 11(1): 24373, 2021 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-34934118

RESUMO

Gestational Diabetes Mellitus (GDM) and obesity affect the functioning of multiple maternal systems and influence colonization of the newborn gastrointestinal through the breastmilk microbiota (BMM). It is currently unclear how GDM and obesity affect the human BMM composition. Here, we applied 16S-rRNA high-throughput sequencing to human colostrum milk to characterize BMM taxonomic changes in a cohort of 43 individuals classified in six subgroups according to mothers patho-physiological conditions (healthy control (n = 18), GDM (n = 13), or obesity (n = 12)) and newborn gender. Using various diversity indicators, including Shannon/Faith phylogenetic index and UniFrac/robust Aitchison distances, we evidenced that BMM composition was influenced by the infant gender in the obesity subgroup. In addition, the GDM group presented higher microbial diversity compared to the control group. Staphylococcus, Corynebacterium 1, Anaerococcus and Prevotella were overrepresented in colostrum from women with either obesity or GDM, compared to control samples. Finally, Rhodobacteraceae was distinct for GDM and 5 families (Bdellovibrionaceae, Halomonadaceae, Shewanellaceae, Saccharimonadales and Vibrionaceae) were distinct for obesity subgroups with an absolute effect size greater than 1 and a q-value ≤ 0.05. This study represents the first effort to describe the impact of maternal GDM and obesity on BMM.


Assuntos
Bactérias/genética , Colostro/microbiologia , Diabetes Gestacional/microbiologia , Microbioma Gastrointestinal , Trato Gastrointestinal/microbiologia , Leite Humano/microbiologia , Obesidade/microbiologia , Adulto , Bactérias/classificação , Bactérias/isolamento & purificação , Índice de Massa Corporal , Feminino , Humanos , Recém-Nascido , Masculino , Filogenia , Gravidez
8.
Water Sci Technol ; 84(9): 2335-2352, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34810315

RESUMO

The vast majority of the energy consumed for urban water services is used to heat tap water. Heat recovery from wastewater is consequently an area of rapidly growing concern, both in research and by commercial interest, promoting the path towards a circular economy. To facilitate a system-wide evaluation of heat recovery from wastewater, this paper compares two one-dimensional models (mechanistic and conceptual) that can describe wastewater temperature dynamics in sewer pipe systems. The models are applied to successfully predict downstream wastewater temperature for sewer stretches in two Swedish cities (Linköping and Malmö). The root mean squared errors for the mechanistic model (Linköping Dataset1 - 0.33 °C; Linköping Dataset2 - 0.28 °C; Malmö - 0.40 °C) and the conceptual model (Linköping Dataset1 - 0.32 °C; Linköping Dataset2 - 0.20 °C; Malmö - 0.44 °C) indicate that both models have similar predictive capabilities, encouraging the use of conceptual models to reduce data requirements and model calibration efforts. Both models are freely distributed and can be easily integrated with wastewater generation and treatment models to facilitate system-wide wastewater temperature dynamics analysis.


Assuntos
Esgotos , Águas Residuárias , Temperatura Alta , Modelos Teóricos , Temperatura
9.
Rev. cir. (Impr.) ; 73(3): 329-337, jun. 2021. ilus
Artigo em Espanhol | LILACS | ID: biblio-1388820

RESUMO

Resumen Introducción: La perforación esofágica es una complicación poco frecuente en la cirugía de columna cervical por vía anterior, sin embargo, puede tener graves consecuencias cuando hay demoras en diagnóstico y tratamiento. Casos Clínicos: Presentamos dos casos clínicos de pacientes con perforación esofágica secundaria a cirugía de columna cervical por vía anterior. Se usaron para su reparación colgajo muscular de esternocleidomastoideo (ECM). Conclusión: La perforación esofágica secundaria a cirugía de columna cervical es poco frecuente, variable desde el punto de vista clínico, el TC y estudio radiológico contrastado son fundamentales en el diagnóstico de esta patología. El colgajo muscular ECM en estos casos es una herramienta fiable y extremadamente útil debido a sus características anatómicas, fácil disección quirúrgica y baja morbilidad asociada.


Introduction: Esophageal perforation is a rare complication in cervical spine surgery by anterior way, however it can have serious consequences when there are delays in diagnosis and treatment. Cases Report: We present two clinical cases of patients with esophageal perforation secondary to cervical spine surgery by anterior way. Sternocleido-mastoid muscle flaps were used for repair. Conclusion: Esophageal perforation secondary to cervical spine surgery is rare, clinically variable, CT and radiologic study are fundamental in the diagnosis of this pathology. The Sternocleidomastoid muscle flap in these cases is a reliable and extremely useful tool due to its anatomical characteristics, easy surgical dissection and low associated morbidity.


Assuntos
Humanos , Idoso , Traumatismos da Coluna Vertebral/cirurgia , Traumatismos da Coluna Vertebral/complicações , Retalhos Cirúrgicos , Perfuração Esofágica/cirurgia , Complicações Pós-Operatórias/prevenção & controle , Vértebras Cervicais/lesões , Perfuração Esofágica/diagnóstico por imagem , Músculos do Pescoço/transplante
10.
Med Oncol ; 37(7): 60, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32524295

RESUMO

To evaluate the outcomes of total eradication therapy (TET), designed to eradicate all sites of visible cancer and micrometastases, in men with newly diagnosed oligometastatic prostate cancer (OMPCa). Men with ≤ 5 sites of metastases were enrolled in a prospective registry study, underwent neoadjuvant chemohormonal therapy, followed by radical prostatectomy, adjuvant radiation (RT) to prostate bed/pelvis, stereotactic body radiation therapy (SBRT) to oligometastases, and adjuvant hormonal therapy (HT). When possible, the prostate-specific membrane antigen targeted 18F-DCFPyL PET/CT (18F-DCFPyL) scan was obtained, and abiraterone was added to neoadjuvant HT. Twelve men, median 55 years, ECOG 0, median PSA 14.7 ng/dL, clinical stages M0-1/12 (8%), M1a-3/12 (25%) and M1b-8/12 (67%), were treated. 18F-DCFPyL scan was utilized in 58% of cases. Therapies included prostatectomy 12/12 (100%), neoadjuvant [docetaxel 11/12 (92%), LHRH agonist 12/12 (100%), abiraterone + prednisone 6/12 (50%)], adjuvant radiation [RT 2/12 (17%), RT + SBRT 4/12 (33%), SBRT 6/12 (50%)], and LHRH agonist 12/12 (100%)]. 2/5 (40%) initial patients developed neutropenic fever (NF), while 0/6 (0%) subsequent patients given modified docetaxel dosing developed NF. Otherwise, TET resulted in no additive toxicities. Median follow-up was 48.8 months. Overall survival was 12/12 (100%). 1-, 2-, and 3-year undetectable PSA's were 12/12 (100%), 10/12 (83%) and 8/12 (67%), respectively. Median time to biochemical recurrence was not reached. The outcomes suggest TET in men with newly diagnosed OMPCa is safe, does not appear to cause additive toxicities, and may result in an extended interval of undetectable PSA.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Próstata/terapia , Anilidas/administração & dosagem , Antígenos de Superfície/sangue , Quimioterapia Adjuvante , Terapia Combinada , Dexametasona/administração & dosagem , Intervalo Livre de Doença , Docetaxel/administração & dosagem , Glutamato Carboxipeptidase II/sangue , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Humanos , Calicreínas/sangue , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Metástase Neoplásica , Estadiamento de Neoplasias , Nitrilas/administração & dosagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Estudos Prospectivos , Antígeno Prostático Específico/sangue , Prostatectomia , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia , Radiocirurgia , Radioterapia Adjuvante , Taxa de Sobrevida , Compostos de Tosil/administração & dosagem
11.
J Dairy Sci ; 103(7): 6114-6134, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32418699

RESUMO

Our objectives were to evaluate technical lignins for their antifungal properties against 3 molds and 1 yeast causing hay spoilage, and their ability to preserve ground high-moisture alfalfa hay nutritive value in vitro. In experiment 1, 8 technical lignins and propionic acid (PRP; positive control) were tested at a dose of 40 mg/mL. The experiment had a randomized complete block design (RCBD, 4 runs) and a factorial arrangement of 3 molds × 10 additives (ADV). The effects of the ADV on yeast were evaluated separately with a RCBD. Sodium lignosulfonate (NaL) and PRP were the only treatments with 100 ± 2.8% inhibition of fungi. In experiment 2, the minimum inhibitory concentration (MIC) for selected lignins and PRP were determined. At pH 4, NaL had the lowest MIC across the molds (20-33.3 mg/mL) and magnesium lignosulfonate (MgL) for the yeast (26.7) among the lignins. However, PRP had MIC values that were several-fold lower across all fungi (1.25-3.33). In experiment 3, a RCBD (5 blocks) with a 3 (ADV; NaL, MgL, and PRP) × 4 (doses: 0, 0.5, 1, and 3% wt/wt fresh basis) factorial arrangement of treatments was used to evaluate the preservative effects of ADV in ground high-moisture alfalfa hay inoculated with a mixture of the fungi previously tested and incubated under aerobic conditions in vitro. After 15 d, relative to untreated hay (14.9), dry matter (DM) losses were lessened by doses as low as 1% for NaL (3.39) and 0.5% for PRP (0.81 ± 0.77%). The mold count was reduced in both NaL at 3% (3.92) and PRP as low as 0.5% (3.94) relative to untreated hay (7.76 ± 0.55 log cfu/fresh g). Consequently, sugars were best preserved by NaL at 3% (10.1) and PRP as low as 0.5% (10.5) versus untreated (7.99 ± 0.283% DM), while keeping neutral detergent fiber values lower in NaL (45.9) and PRP-treated (45.1) hays at the same doses, respectively, relative to untreated (49.7 ± 0.66% DM). Hay DM digestibility was increased by doses as low as 3% for NaL (67.5), 1% MgL (67.0), and 0.5% PRP (68.5) versus untreated hay (61.8 ± 0.77%). The lowest doses increasing neutral detergent fiber digestibility relative to untreated hay (23.3) were 0.5% for MgL and PRP (30.5 and 30.1, respectively) and 1% for NaL (30.7 ± 1.09% DM). Across technical lignins, NaL showed the most promise as a potential hay preservative. However, its effects were limited compared with PRP at equivalent doses. Despite not having an effect on preservation, MgL improved DM digestibility by stimulating neutral detergent fiber digestibility. This study warrants further development of NaL under field conditions.


Assuntos
Ração Animal/microbiologia , Conservantes de Alimentos/química , Fungos/efeitos dos fármacos , Lignina/análogos & derivados , Lignina/química , Medicago sativa , Animais , Microbiologia de Alimentos , Conservação de Alimentos
12.
Nanotechnology ; 31(2): 025706, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31550683

RESUMO

InSb/InAs sub-monolayer (SML) nanostructures such as SML quantum dots offer sharper emission spectra, a better modal gain and a larger modulation bandwidth compared to its Stranski-Krastanov counterpart. In this work, the Sb distribution of SML InSb layers grown by migration enhanced epitaxy has been analyzed by transmission electron microscopy (TEM) techniques. The analysis of the material by diffraction contrast in 002 dark field conditions and by atomic column resolved high angle annular dark field-scanning TEM reveal the presence of a low Sb content InSbAs continuous layer with scarce Sb-rich InSbAs agglomerates. The intensity profiles obtained by both techniques point to Sb segregation during growth. This segregation has been quantified using the Muraki segregation model obtaining a high segregation coefficient R of 0.81 towards the growth direction. The formation of a continuous InSbAs wetting layer as a result of a SML deposition of Sb on the InAs surface is discussed.

14.
Trop Anim Health Prod ; 50(8): 1797-1805, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29948775

RESUMO

The study evaluated small-scale dairy systems with continuous grazing of pastures based on three temperate grasses festulolium (FL), tall fescue (TF), and perennial ryegrass (RG), compared with subtropical kikuyu grass (KG). All pastures were associated with white clover (Trifolium repens L.). Twelve multiparous Holstein cows were assigned to a 4 × 4 Latin square replicated three times with 14-day experimental periods. Sampling and analyses of pastures, concentrates, and animal variables followed standard procedures. FL showed a significantly (p < 0.05) higher mean sward height, but there were no differences (p > 0.05) in net herbage accumulation. There were significant differences (p < 0.05) among pastures for CP, NDF, ADF, in vitro digestibility of OM (IVOMD), and estimated metabolizable energy (eME). There were no differences (p > 0.05) between treatments for milk yield and composition, live weight, or body condition score. There were significant differences (p < 0.05) in fatty acid values for pastures in C14:0, C16:1, and C18:3n3. There were significant differences between treatments (p < 0.05) in milk contents for C18:0, C18:1t11, and C18:2c9t11. Grazing FL, TF, RG, or KY pastures showed no differences in milk yields. Higher values for C18:0, C18:1t11, and C18:2c9t11 were detected in KY, RG, and TF. RG had significantly higher MUFA than FL and higher PUFA than TF. A value under 65% of SFA, a ratio of n-6/n-3 lower than 4, and an atherogenic index of 1.7 are indicators of milk with beneficial effects for human health.


Assuntos
Ração Animal/análise , Indústria de Laticínios/métodos , Ácidos Graxos/química , Leite/química , Poaceae , Animais , Bovinos , Feminino , Lactação , Ácidos Linoleicos Conjugados/química , Lolium , México , Chuva , Distribuição Aleatória , Estações do Ano , Trifolium
15.
Haemophilia ; 24(4): e222-e229, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29902356

RESUMO

INTRODUCTION: Patients with haemophilia may have lower levels of bone mineral density (BMD) compared with the general population. Moreover, haemophilic patients have increased risk factors for low bone mineral density (LBMD) such as arthropathy and resulting immobility, increasing their risk for osteoporosis and fractures. AIM: To assess the prevalence of LBMD and associated risk factors among a group of Colombian haemophilic patients. METHODS: In this case-control study, 90 patients with haemophilia A and B, over the age of five, were recruited. Controls were healthy participants matched by age, gender, body mass index (BMI), socioeconomic status, and race. All participants underwent dual energy X-ray absorptiometry (DXA) and the Global Physical Activity Questionnaire. Blood tests were collected to evaluate LBMD determinants in cases. RESULTS: BMD was lower in cases than in the control group. BMD of femoral necks was 0.907 g/cm2 in cases vs. 1.020 g/cm2 in controls (P = .019), and BMD of hips 0.930 g/cm2 in cases vs. 1030 g/cm2 in controls (P = .019). The greater the severity of haemophilia, the lower BMD in spine, femoral neck, and hips. Elevated C-protein levels were found in 44.1% of patients with LBMD and 14.8% with normal BMD (P = .003). The study found an adjusted prevalence ratio of 2.11, indicating that haemophilic patients are two times more likely to have LBMD (CI95% = 1.43-3.11 P < .001). CONCLUSION: Results from the present study showed that haemophilia was associated with a higher frequency of LBMD. Severity of haemophilia, haemophilic arthropathy, and elevated C-reactive protein levels was directly associated with LBMD.


Assuntos
Densidade Óssea , Hemofilia A/fisiopatologia , Hemofilia B/fisiopatologia , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Pré-Escolar , Colômbia , Feminino , Hemofilia A/complicações , Hemofilia B/complicações , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Adulto Jovem
16.
Micron ; 110: 18-27, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29705338

RESUMO

During image acquisition of crystalline materials by high-resolution scanning transmission electron microscopy, the sample drift could lead to distortions and shears that hinder their quantitative analysis and characterization. In order to measure and correct this effect, several authors have proposed different methodologies making use of series of images. In this work, we introduce a methodology to determine the drift angle via Fourier analysis by using a single image based on the measurements between the angles of the second Fourier harmonics in different quadrants. Two different approaches, that are independent of the angle of acquisition of the image, are evaluated. In addition, our results demonstrate that the determination of the drift angle is more accurate by using the measurements of non-consecutive quadrants when the angle of acquisition is an odd multiple of 45°.

17.
J Phys Condens Matter ; 30(17): 175601, 2018 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-29533222

RESUMO

Superconductivity in strongly correlated systems is a remarkable phenomenon that attracts huge interest. The study of this problem is relevant for materials such as the high T c oxides, pnictides and heavy fermions. These systems also have in common the existence of electrons of several orbitals that coexist at a common Fermi surface. In this paper we study the effect of pressure, chemical or applied on multi-band superconductivity. Pressure varies the atomic distances and consequently the overlap of the wave-functions in the crystal. This rearranges the electronic structure that we model including a pressure dependent hybridization between the bands. We consider the case of two-dimensional systems in a square lattice with inverted bands. We study the conditions for obtaining a pressure induced superconductor quantum critical point and show that hybridization, i.e. pressure can induce a Bardeen-Cooper-Schrieffer-Bose-Einstein condensation crossover in multi-band systems even for moderate interactions. We found a tail-like superconductor regime and briefly discuss the influence of the symmetry of the order parameter in the results.

18.
Mult Scler Relat Disord ; 20: 122-128, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29414284

RESUMO

BACKGROUND: Cognitive impairment is a relevant contributor of the medical and social burden in Progressive MS. Social Cognition, the neurocognitive processes underlying social interaction, has been explored mainly in European and North American cohorts, influencing social aspects of quality of life (QOL) of early MS patients and families. Few studies have studied Social Cognition in Progressive MS and the literature on its neuroanatomical bases or brain atrophy measurements is still scarce. OBJECTIVES: To explore the relationship between Social Cognition performance and its correlations with traditional cognitive domains, brain atrophy and QOL in primary and secondary Progressive MS patients. METHODS: Cross-sectional analysis including: mini-Social-Cognition-and-Emotional-Assessment (mini-SEA), neuropsychological battery, disability, depression, fatigue, QOL, and brain volume. RESULTS: Forty-three MS patients, 23 primary and 20 secondary Progressive, 65% women, mean age and disease duration of 57.2 and 15.7 years, respectively, with high levels of disability (median EDSS 6.0) and a widespread impairment in traditional domains (mostly episodic verbal/visual and working memories) were assessed. The Mini-SEA score was correlated with executive functions (cognitive shifts Rho:0.55; p = 0.001) analyzing the whole group, and with visual episodic memory (Rho:0.58, p = 0.009) in the primary Progressive MS group. Mini-SEA score was also correlated with total normalized grey matter volume (Rho:0.48; p = 0.004). Particularly, atrophy within bilateral cortical regions of orbitofrontal, insula and cerebellum, and right regions of fusiform gyrus and precuneus were significantly associated with higher Social Cognition impairment. In this cohort, QOL was not correlated with Social Cognition, but with EDSS, fatigue and depression. CONCLUSIONS: In Progressive MS, Social Cognition is directly correlated with traditional cognitive domains such as executive function and episodic memory. It is also associated with global grey matter atrophy and regional atrophy within associative visual and executive cortical areas, but no correlations with QOL were found in this cohort. These findings may contribute to the understanding of the pathological bases behind Social Cognition in Progressive MS.


Assuntos
Encéfalo/diagnóstico por imagem , Cognição , Esclerose Múltipla Crônica Progressiva/psicologia , Percepção Social , Adulto , Idoso , Atrofia , Encéfalo/patologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/patologia , Estudos Transversais , Depressão/diagnóstico por imagem , Depressão/patologia , Avaliação da Deficiência , Fadiga/diagnóstico por imagem , Fadiga/patologia , Feminino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Humanos , Masculino , Memória Episódica , Pessoa de Meia-Idade , Esclerose Múltipla Crônica Progressiva/complicações , Esclerose Múltipla Crônica Progressiva/patologia , Tamanho do Órgão , Estudos Prospectivos , Qualidade de Vida , Percepção Visual
19.
Nanotechnology ; 28(42): 425702, 2017 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-28770809

RESUMO

A procedure to quantitatively analyse the relationship between the wetting layer (WL) and the quantum dots (QDs) as a whole in a statistical way is proposed. As we will show in the manuscript, it allows determining, not only the proportion of deposited InAs held in the WL, but also the average In content inside the QDs. First, the amount of InAs deposited is measured for calibration in three different WL structures without QDs by two methodologies: strain mappings in high-resolution transmission electron microscopy images and compositional mappings with ChemiSTEM x-ray energy spectrometry. The area under the average profiles obtained by both methodologies emerges as the best parameter to quantify the amount of InAs in the WL, in agreement with high-resolution x-ray diffraction results. Second, the effect of three different GaAs capping layer (CL) growth rates on the decomposition of the QDs is evaluated. The CL growth rate has a strong influence on the QD volume as well as the WL characteristics. Slower CL growth rates produce an In enrichment of the WL if compared to faster ones, together with a diminution of the QD height. In addition, assuming that the QD density does not change with the different CL growth rates, an estimation of the average In content inside the QDs is given. The high Ga/In intermixing during the decomposition of buried QDs does not only trigger a reduction of the QD height, but above all, a higher impoverishment of the In content inside the QDs, therefore modifying the two most important parameters that determine the optical properties of these structures.

20.
Ultramicroscopy ; 182: 283-291, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28783580

RESUMO

High-quality image reconstruction techniques allow the generation of high pixel density images from a set of low-resolution micrographs. In general, these techniques consist of two main steps, namely, accurate registration, and formulation of an appropriate forward image model via some restoration method. There exist a wide variety of algorithms to cope with both stages and depending on their practical applications, some methods can outperform others, since they can be sensitive to the assumed data model, noise, drift, etc. When dealing with images generated by Z-contrast scanning transmission electron microscopes, a current trend is based on non-rigid approximations in the registration stage. In our work we aimed at reaching similar accuracy but addressing the most complex calculations in the reconstruction stage, instead of in the registration stage (as the non-rigid approaches do), but using a much smaller number of images. We review some of the most significant methods and address their shortcomings when they are applied to the field of microscopy. Simulated images with known targets will be used to evaluate and compare the main approaches in terms of quality enhancement and computing time. In addition, a procedure to determine the reference image will be proposed to minimise the global drift on the series. The best registration and restoration strategies will be applied to experimental images in order to point up the enhanced capability of this high quality image reconstruction methodology in this field.

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