Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 114
Filtrar
1.
Ann Pharm Fr ; 80(6): 827-836, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35568247

RESUMO

OBJECTIVES: In the management of diabetic patients on insulin therapy, adherence to medication is a key element for avoiding chronic complications. The purpose of this study was to evaluate diabetic patients' ability to translate glycemic results into an appropriate insulin dose and thus, adherence to insulins. METHODS: This was an observational, retrospective, monocentric pilot study. Diabetic patients on insulin therapy being followed at the metabolic and endocrine diseases department were divided into two groups depending on their mode of glycemic control at home: capillary glycemia (Notebook group) or interstitial glycemia using the FreeStyle Libre® flash system (FSL group). Adherence was assessed based on the rate of compliance in adapting insulin doses to the prescribed protocols (depending on type of insulin, glycemic targets, and patients' characteristics) by a pharmacy resident and a senior diabetologist. Good adherence was defined as a minimum rate of 80% of conforming insulin injections for each patient. RESULTS: A total of 50 patients were included, 35 in the Notebook group and 15 in the FSL group. Two-thirds of patients were non-adherent to insulin. Dose adjustment errors mainly concerned rapid-acting insulin with 51.1% of non- conformities, 10.0% of which were due to underdosing in the Notebook group and 21.7% to overdosing in the FSL group. Hyperglycemia was predominant in both populations with a median time in range of 19.0% in the FSL group and well below recommendations (>70%). CONCLUSIONS: Despite the use of increasingly efficient, easy-to-use devices in diabetes monitoring, insulin non-adherence and glycemic imbalance are unresolved major issues. Diabetic patients require reinforced medical follow-up for optimal insulin management.


Assuntos
Diabetes Mellitus , Insulinas , Humanos , Insulina/uso terapêutico , Hipoglicemiantes/uso terapêutico , Estudos Retrospectivos , Pacientes Ambulatoriais , Projetos Piloto , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/induzido quimicamente , Glicemia , Insulina de Ação Curta
2.
Sensors (Basel) ; 22(6)2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35336485

RESUMO

The early prediction of changes in disease state allows timely treatment of patients with inflammatory bowel disease (IBD) to be performed, which improves disease outcome. The aim of this pilot study is to explore the potential of fecal volatile organic compound (VOC) profiles to predict disease course. In this prospective cohort, IBD patients were asked to collect two fecal samples and fill in a questionnaire at set intervals. Biochemically, active disease was defined by FCP ≥ 250 mg/g and remission was defined by FCP < 100 mg/g. Clinically, active disease was defined by a Harvey Bradshaw Index (HBI) ≥ 5 for Crohn's disease or by a Simple Clinical Colitis Activity Index (SCCAI) ≥ 3 for ulcerative colitis. Clinical remission was defined by an HBI < 4 or SCCAI ≤ 2. Fecal VOC profiles were measured using gas chromatography-ion mobility spectrometry (GC-IMS). The fecal samples collected first were included for VOC analysis to predict disease state at the following collection. A total of 182 subsequently collected samples met the disease-state criteria. The fecal VOC profiles of samples displaying low FCP levels at the first measurements differed between patients preceding exacerbation versus those who remained in remission (AUC 0.75; p < 0.01). Samples with FCP levels at the first time point displayed different VOC profiles in patients preceding remission compared with those whose disease remained active (AUC 0.86; p < 0.01). Based on disease activity scores, there were no significant differences in any of the comparisons. Alterations in fecal VOC profiles preceding changes in FCP levels may be useful to detect disease-course alterations at an early stage. This could lead to earlier treatment, decreased numbers of complications, surgery and hospital admission.


Assuntos
Colite Ulcerativa , Doenças Inflamatórias Intestinais , Colite Ulcerativa/diagnóstico , Humanos , Doenças Inflamatórias Intestinais/diagnóstico , Odorantes , Projetos Piloto , Estudos Prospectivos
3.
ACS Appl Mater Interfaces ; 13(29): 34923-34934, 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34264646

RESUMO

Dropwise condensation is favorable for numerous industrial and heat/mass transfer applications due to the enhanced heat transfer performance that results from efficient condensate removal. Organofunctional silane self-assembled monolayer (SAM) coatings are one of the most common ultrathin low surface energy materials used to promote dropwise condensation of water vapors because of their minimal thermal resistance and scalable synthesis process. These SAM coatings typically degrade (i.e., condensation transitions from the efficient dropwise mode to the inefficient filmwise mode) rapidly during water vapor condensation. More importantly, the condensation-mediated coating degradation/failure mechanism(s) remain unknown and/or unproven. In this work, we develop a mechanistic understanding of water vapor condensation-mediated organofunctional silane SAM coating degradation and validate our hypothesis through controlled coating synthesis procedures on silicon/silicon dioxide substrates. We further demonstrate that a pristine organofunctional silane SAM coating resulting from a water/moisture-free coating environment exhibits superior long-term robustness during water vapor condensation. Our molecular/nanoscale surface characterizations, pre- and post-condensation heat transfer testing, indicate that the presence of moisture in the coating environment leads to uncoated regions of the substrate that act as nucleation sites for coating degradation. By elucidating the reasons for formation of these degradation nuclei and demonstrating a method to suppress such defects, this study provides new insight into why low surface energy silane SAM coatings degrade during water vapor condensation. The proposed approach addresses a key bottleneck (i.e., coating failure) preventing the adoption of efficient dropwise condensation methods in industry, and it will facilitate enhanced phase-change heat transfer technologies in industrial applications.

4.
ACS Appl Mater Interfaces ; 13(16): 19369-19376, 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33861561

RESUMO

In an effort to protect metal substrates from extreme heat, polymer-clay multilayer thin films are studied as expendable thermal barrier coatings. Nanocomposite films with a thickness ranging from 2 to 35 µm were deposited on steel plates and exposed to the flame from a butane torch. The 35 µm coating, composed of 14 deposited bilayers of tris(hydroxymethyl)aminomethane (THAM)-buffered polyethylenimine (PEI) and vermiculite clay (VMT), decreased the maximum temperature observed on the back side of a 0.32 cm thick steel plate by over 100 °C when heated with a butane torch. Upon exposure to high temperature, the polymer and amine salt undergo pyrolysis and intumesce, subsequently forming a char and blowing gas. The char encases the nanoclay platelets, and a ceramic bubble is formed. The macro-scale bubble, in tandem with the nanocomposite coating properties, increases resistance to heat transfer into the underlying metal substrate. This heat shielding behavior occurs through radiative effects and low aggregate through-plane conductivity resulting from multilayer nanodomains and intumesced porosity (i.e., conduction through the gas as the film expands to form a ceramic bubble). These relatively thin and lightweight films could be used to protect important metal parts (in automobiles, aircraft, etc.) from fire-related damage or other types of transient high-temperature situations.

5.
J Dairy Sci ; 104(7): 7794-7807, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33865595

RESUMO

This study investigated the use of K2CO3 as dietary buffer to prevent or to recover from low milk fat production when early-lactating dairy goats are fed a high-starch, low-fiber (HSLF) diet. At kidding, 30 Alpine goats housed in pens with Calan gate feeders received a total mixed ration with a forage-to-concentrate ratio of 55:45 on a dry matter (DM) basis for a baseline period of 27 ± 4 d. Goats (milk yield, 4.14 ± 0.88 kg/d; milk fat, 4.28 ± 0.52%; mean ± SD) were then assigned to 1 of 10 blocks according to parity (first vs. second or more) and milk fat concentration, and fed a HSLF diet containing 45% forages and 55% concentrates for 2 experimental periods of 28 d. Treatments were identified as (1) control, in which the HSLF diet was fed throughout both periods; (2) preventive, in which the HSLF diet supplemented with K2CO3 (1.6% of DM) was fed during both periods; and (3) recovery, in which the HSLF diet was fed during the first period (P1) and the HSLF diet supplemented with K2CO3 was fed during the second period (P2). Data from P1 and P2 were analyzed separately. In P1, preplanned contrasts were used to evaluate the preventive effect of K2CO3 (control and recovery, both groups receiving the same diet during this period, vs. preventive), and in P2, to assess the potential of K2CO3 to alleviate an already existing state of low milk fat (control vs. recovery and preventive vs. recovery). Feeding the HSLF diet in P1 moderately decreased milk fat concentration (-16%) and yield (-13%) as compared with baseline. Dietary addition of K2CO3 decreased DM intake by 12 and 14% in P1 and P2, respectively. Ruminal pH was not different among treatments. There was also no significant difference in milk yield (4.13 and 3.71 kg/d on average in P1 and P2, respectively) for any tested contrasts. In P1, milk fat concentration and yield did not differ among goats fed control (3.58% and 151 g/d, respectively) and preventive (3.67% and 148 g/d, respectively) diets. In P2, milk fat concentration and yield did not differ among goats fed the control diet (3.38% and 137 g/d, respectively), and diets where K2CO3 was used as preventive (3.44% and 126 g/d, respectively) or recovery treatment (3.25% and 113 g/d, respectively). Supplementing a high-concentrate diet with 1.6% K2CO3 was therefore not effective in either preventing or suppressing already existing conditions of low milk fat production in dairy goats.


Assuntos
Lactação , Leite , Ração Animal/análise , Animais , Carbonatos , Dieta/veterinária , Suplementos Nutricionais , Feminino , Cabras , Potássio , Rúmen , Amido
6.
J Exp Bot ; 72(2): 654-681, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33449086

RESUMO

Plastid sequences have long dominated phylogeny reconstruction at all time depths, predicated on a usually untested assumption that they accurately represent the evolutionary histories of phenotypically circumscribed species. We combined detailed in situ morphometrics (124 plants) and whole-plastome sequencing through genome skimming (71 plants) in order to better understand species-level diversity and speciation in arguably the most challenging monophyletic group within the taxonomically controversial, pseudo-copulatory bee orchid genus Ophrys. Using trees and ordinations, we interpreted the data at four nested demographic levels-macrospecies, mesospecies, microspecies, and local population-seeking the optimal level for bona fide species. Neither morphological nor molecular discontinuities are evident at any level below macrospecies, the observed overlap among taxa suggesting that both mesospecies and microspecies reflect arbitrary division of a continuum of variation. Plastomes represent geographic location more strongly than taxonomic assignment and correlate poorly with morphology, suggesting widespread plastid capture and possibly post-glacial expansion from multiple southern refugia. As they are rarely directly involved in the speciation process, plastomes depend on extinction of intermediate lineages to provide phylogenetic signal and so cannot adequately document evolutionary radiations. The popular 'ethological' evolutionary model recognizes as numerous 'ecological species' (microspecies) lineages perceived as actively diverging as a result of density-dependent selection on very few features that immediately dictate extreme pollinator specificity. However, it is assumed rather than demonstrated that the many microspecies are genuinely diverging. We conversely envisage a complex four-dimensional reticulate network of lineages, generated locally and transiently through a wide spectrum of mechanisms, but each unlikely to maintain an independent evolutionary trajectory long enough to genuinely speciate by escaping ongoing gene flow. The frequent but localized microevolution that characterizes the Ophrys sphegodes complex is often convergent and rarely leads to macroevolution. Choosing between the contrasting 'discontinuity' and 'ethology' models will require next-generation sequencing of nuclear genomes plus ordination of corresponding morphometric matrices, seeking the crucial distinction between retained ancestral polymorphism-consistent with lineage divergence-and polymorphisms reflecting gene flow through 'hybridization'-more consistent with lineage convergence.


Assuntos
Orchidaceae , Animais , Abelhas/genética , Demografia , Fluxo Gênico , Orchidaceae/genética , Filogenia
7.
ACS Nano ; 14(11): 14878-14886, 2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33185426

RESUMO

Hydrophobic coatings with low thermal resistance promise a significant enhancement in condensation heat transfer performance by promoting dropwise condensation in applications including power generation, water treatment, and thermal management of high-performance electronics. However, after nearly a century of research, coatings with adequate robustness remain elusive due to the extreme environments within many condensers and strict design requirements needed to achieve enhancement. In this work, we enable long-lasting condensation heat transfer enhancement via dropwise condensation by infusing a hydrophobic polymer, Teflon AF, into a porous nanostructured surface. This polymer infused porous surface (PIPS) uses the large surface area of the nanostructures to enhance polymer adhesion, while the nanostructures form a percolated network of high thermal conductivity material throughout the polymer and drastically reduce the thermal resistance of the composite. We demonstrate over 700% enhancement in the condensation of steam compared to an uncoated surface. This performance enhancement was sustained for more than 200 days without significant degradation. Furthermore, we show that the surfaces are self-repairing upon raising the temperature past the melting point of the polymer, allowing recovery of hydrophobicity and offering a level of durability more appropriate for industrial applications.

8.
Arch Virol ; 165(10): 2389-2392, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32699979

RESUMO

A novel tobamovirus, brugmansia latent virus (BrLV), was discovered during a study of brugmansia (Brugmansia spp.) in the living collections held at the Royal Botanic Gardens, Kew. Here, we report the complete genome sequence of BrLV, which is 6,397 nucleotides long and contains the four open reading frames (RNA-dependent RNA polymerase, methyltransferase/helicase, movement, and coat proteins) typical of tobamoviruses. The complete genome sequence of BrLV shares 69.7% nucleotide sequence identity with brugmansia mild mottle virus (BrMMV) and 66.7 to 68.7% identity with other tobamoviruses naturally infecting members of the Solanaceae plant family. Phylogenetic analysis of the complete genome nucleotide sequence and the deduced amino acid sequences of the four tobamovirus proteins place BrLV in a subcluster with BrMMV within the Solanaceae-infecting tobamovirus subgroup as a new species.


Assuntos
Brugmansia/virologia , Proteínas do Capsídeo/genética , Genoma Viral , RNA Viral/genética , Tobamovirus/genética , Sequência de Bases , Sequência Conservada , Metiltransferases/genética , Fases de Leitura Aberta , Filogenia , Doenças das Plantas/virologia , RNA Polimerase Dependente de RNA/genética , Alinhamento de Sequência , Tobamovirus/classificação , Tobamovirus/isolamento & purificação , Reino Unido , Sequenciamento Completo do Genoma
9.
Dig Liver Dis ; 52(7): 745-752, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32402741

RESUMO

BACKGROUND: Inflammatory bowel disease (IBD) is diagnosed and monitored using endoscopic assessment, which is invasive and costly. In this study, potential of faecal volatile organic compounds (VOC) analysis for IBD detection and identification of disease activity was evaluated. METHODS: IBD patients visiting outpatient clinics of participating tertiary hospitals were included. Active disease was defined as FCP ≥250 mg/g, remission as FCP <100 mg/g with Harvey Bradshaw Index <4 for Crohn's disease (CD) or Simple Clinical Colitis Activity Index <3 for ulcerative colitis (UC). Healthy controls (HC) were patients without mucosal abnormalities during colonoscopy. Faecal samples were measured using gas chromatography-ion mobility spectrometry. RESULTS: A total of 280 IBD patients collected 107 CDa, 84 CDr, 80 UCa and 63 UCr samples. Additionally, 227 HC provided one faecal sample. UC and CD were discriminated from HC with high accuracy (AUC (95%CI): UCa vs HC 0.96(0.94-0.99); UCr vs HC 0.95(0.93-0.98); CDa vs HC 0.96(0.94-0.99); CDr vs HC 0.95(0.93-0.98)). There were small differences between UC and CD (0.55(0.50-0.6)) and no differences between active disease and remission (UCa vs UCr 0.63(0.44-0.82); CDa vs CDr 0.52(0.39-0.65)). CONCLUSION: Our study outcomes imply that faecal VOC analysis holds potential for identifying biomarkers for IBD detection but not for monitoring disease activity.


Assuntos
Fezes/química , Doenças Inflamatórias Intestinais/diagnóstico , Espectrometria de Mobilidade Iônica/métodos , Compostos Orgânicos Voláteis/análise , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/análise , Testes Respiratórios , Estudos de Casos e Controles , Colite Ulcerativa/diagnóstico , Colonoscopia , Doença de Crohn/diagnóstico , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Países Baixos , Curva ROC , Adulto Jovem
10.
ACS Appl Mater Interfaces ; 12(6): 7232-7238, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31951381

RESUMO

Water is often considered as the highest performance working fluid for liquid-vapor phase change due to its high thermal conductivity and large enthalpy of vaporization. However, a wide range of industrial systems require using low surface tension liquids where heat transfer enhancement has proved challenging for boiling and evaporation. Here, we enable a new paradigm of phase change heat transfer, which favors high volatility, low surface tension liquids rather than water. We utilized a nanoporous membrane of ≈600 nm thickness and <140 nm pore diameters supported on efficient liquid supply architectures, decoupling capillary pumping from viscous loss. Proof-of-concept devices were microfabricated and tested in a custom-built environmental chamber. We used R245fa, pentane, methanol, isopropyl alcohol, and water as working fluids with devices of total membrane area varying from 0.017 to 0.424 cm2. We realized a device-level pure evaporation heat flux of 144 ± 6 W/cm2 for water, and the highest evaporation heat flux was obtained with pentane at 550 ± 90 W/cm2. We developed a three-level model to understand vapor dynamics near the interface and thermal conduction within the device, which showed good agreement with experiments. We then compared pore-level heat transfer of different fluids, where R245fa showed approximately 10 times the performance of water under the same working conditions. Finally, we illustrate the usefulness of a figure of merit extracted from the kinetic theory for evaporation. The current work provides fundamental insights into the evaporation of low surface tension liquids, which can impact various applications such as refrigeration and air conditioning, petroleum and solvent distillation, and on-chip electronics cooling.

11.
Langmuir ; 35(40): 12927-12935, 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31525296

RESUMO

Thin-film evaporation from micropillar array porous media has gained attention in a number of fields including energy conversion and thermal management of electronics. Performance in these applications is enhanced by leveraging the geometries of the micropillar arrays to both optimize flow through these arrays via capillary pumping and increase the curved liquid-vapor interface (meniscus) area for active phase-change heat transfer. In this work, we present a unified semianalytical modeling framework to predict the dry-out heat flux accurately for thin-film evaporation from micropillar arrays with the precise prediction of (i) the pressure profile along the wick achieved by discretizing the porous media domain and (ii) the local permeability that depends on the local meniscus shape. We validate the permeability model with 3D numerical simulations and verify the accuracy of the thin-film evaporation modeling framework with available experimental data from the literature. We emphasize the importance of predicting an accurate liquid-vapor interface shape for the prediction accuracy of both the permeability and the associated governing equations for liquid propagation and phase-change heat transfer through porous materials. This modeling framework is an accurate non-CFD-based methodology for predicting the dry-out heat flux during thin-film evaporation from micropillar arrays and will serve as a general framework for modeling steady liquid-vapor phase-change processes (evaporation and condensation) in porous media.

12.
Dig Liver Dis ; 51(9): 1265-1269, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31213405

RESUMO

BACKGROUND: Inflammatory bowel disease (IBD) patients are at risk of an impaired nutritional status. The impact thereof on the IBD relapse risk is clinically relevant, though sparsely investigated. AIM: The aim was to explore the association between an impaired nutritional status risk and the occurrence of disease flares in IBD outpatients participating in a longitudinal telemedicine study. METHODS: IBD outpatients were recruited from the myIBDcoach study cohort, with one year clinical follow-up. Through myIBDcoach, a telemedicine tool, patients reported on disease activity and risk of impaired nutritional status (i.e. Short Nutritional Assessment Questionnaire >1 and/or BMI < 18.5 kg/m2) every one to three months. Data was analysed by generalized estimating equation modelling. RESULTS: In total, 417 patients were included. During follow-up, 49 patients (11.8%) flared after initial clinical remission and 53 patients (12.7%) showed an increased risk of impaired nutritional status. The risk of impaired nutritional status was associated with flare occurrence (OR 2.61 (95% CI 1.02-6.69)). CONCLUSIONS: The risk of an impaired nutritional status was associated with subsequent flares in IBD outpatients. This emphasizes the importance of monitoring disease activity in IBD patients at risk of impaired nutritional status.


Assuntos
Doenças Inflamatórias Intestinais/complicações , Desnutrição/epidemiologia , Estado Nutricional , Exacerbação dos Sintomas , Adolescente , Adulto , Idoso , Feminino , Humanos , Doenças Inflamatórias Intestinais/fisiopatologia , Estudos Longitudinais , Masculino , Desnutrição/etiologia , Pessoa de Meia-Idade , Análise Multivariada , Países Baixos/epidemiologia , Avaliação Nutricional , Pacientes Ambulatoriais , Fatores de Risco , Inquéritos e Questionários , Telemedicina , Adulto Jovem
13.
J Acoust Soc Am ; 145(5): 2932, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31153354

RESUMO

Generation and development of acoustic waves in an air-filled cylindrical resonator driven by a conical electro-mechanical speaker are studied experimentally and simulated numerically. The driving frequencies of the speaker are chosen such that a standing wave field is produced at each chosen frequency in the resonator. The amplitude of the generated acoustic (pressure) waves is measured along the axis of the resonator by a fast response piezo-resistive pressure transducer, while the radial distribution of the oscillatory axial velocities is measured at the corresponding velocity anti-node locations by a constant temperature hot-film anemometer. For the cases studied, the acoustic Reynolds number ranged between 20.0 and 60.0 and the flow fields were always found to be in the laminar regime. The flow field in the resonator is also simulated by a high-fidelity numerical scheme with low numerical diffusion. Formation of the standing wave and quasi-steady acoustic streaming are numerically simulated by solving the fully compressible form of the Navier-Stokes equations. The effects of the sound field intensity (i.e., input power to the speaker) and driving frequency on the standing wave field and the resultant formation process of the streaming structures are also investigated.

14.
J Crohns Colitis ; 13(10): 1273-1282, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-30810207

RESUMO

BACKGROUND: Microbial shifts have been associated with disease activity in Crohn's disease [CD], but findings on specific taxa are inconsistent. This may be due to differences in applied methods and cross-sectional study designs. We prospectively examined the faecal microbiota in adult CD patients with changing or stable disease course over time. METHODS: Faeces were collected at two time-points from 15 healthy control individuals [HCs], 35 CD patients who were in remission and who maintained remission [RRs], and 22 CD patients during remission and also during subsequent exacerbation [RAs]. The microbial composition was assessed by 16S rRNA [V4] gene sequencing. RESULTS: Compared with HCs, patients with CD had a lower microbial richness [p = 0.0002] and diversity [p = 0.005]. Moreover, the microbial community structure of a subset of patients, clustered apart from HCs, was characterized by low microbial diversity and Faecalibacterium abundance. Patients within this cluster did not differ with respect to long-term disease course compared with patients with a 'healthy-appearing' microbiota.Over time, microbial richness and diversity did not change in RR versus RA patients. Although the microbial community structure of both RR and RA patients was less stable over time compared with that of HCs, no differences were observed between the patient groups [p = 0.17]; nor was the stability impacted by Montreal classification, medication use, or surgery. CONCLUSION: The altered microbiota composition and stability in CD was neither associated with disease activity nor long-term disease course, questioning its involvement in the development of an exacerbation. The aberrant microbiota composition in a subset of CD patients warrants further exploration of a more microbiota-driven etiology in this group.


Assuntos
Doença de Crohn/microbiologia , Fezes/microbiologia , Microbioma Gastrointestinal , Adulto , Estudos de Casos e Controles , Doença de Crohn/patologia , Progressão da Doença , Feminino , Microbioma Gastrointestinal/genética , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , RNA Ribossômico 16S/genética
15.
J Crohns Colitis ; 13(4): 410-416, 2019 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-30371776

RESUMO

BACKGROUND AND AIMS: Inflammatory bowel disease [IBD] is characterized by recurrent disease flares. The impact of psychosocial wellbeing on the occurrence of flares is unclear. In this prospective study, we aimed to evaluate the association between patient-reported psychosocial wellbeing and disease flares using continuous monitoring. METHODS: Consecutive IBD patients were recruited from the myIBDcoach telemedicine study cohort. Over 12 months, participants reported on disease activity together with anxiety, depression, fatigue, perceived stress and life events every 1-3 months. Flares were defined using a combination of clinical disease activity and additional measurements. Generalized estimating equation models were used to assess associations between psychosocial wellbeing and flares over time. The influences of both the presence of psychosocial symptoms in general as well as novel psychosocial symptoms were analysed. RESULTS: In total, 417 patients were included. Forty-nine patients [11.8%] experienced a flare during the study period. The occurrence of life events in the preceding 3 months was positively associated with flares (odds ratio [OR] = 1.81; 95% confidence interval [CI] = 1.04-3.17), while the presence of anxiety, depression, fatigue and perceived stress in general was not. However, novel perceived stress [OR = 2.92; 95% CI = 1.44-5.90] was associated with flares. CONCLUSIONS: The occurrence of life events and novel perceived stress are associated with disease flares in the next 3 months, while the presence of perceived stress in general is not. These findings underline the importance of continuous personalized monitoring of IBD patients and may contribute to the prevention of disease flares.


Assuntos
Doenças Inflamatórias Intestinais/etiologia , Acontecimentos que Mudam a Vida , Estresse Psicológico/psicologia , Exacerbação dos Sintomas , Adolescente , Adulto , Idoso , Ansiedade/psicologia , Depressão/psicologia , Fadiga/psicologia , Feminino , Seguimentos , Humanos , Internet , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Inquéritos e Questionários , Telemedicina , Adulto Jovem
16.
Langmuir ; 34(46): 13855-13863, 2018 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-30372087

RESUMO

Condensation is prevalent in various industrial and heat/mass transfer applications, and improving condensation heat transfer has a direct effect on process efficiency. Enhancing condensation performance has historically been achieved via the use of low surface energy coatings to promote the efficient dropwise mode over the typical filmwise mode of condensation. However, low surface tension fluids condense on these coatings in the filmwise mode, and low surface energy coatings are generally not robust at thicknesses required to enhance condensation heat transfer. We present a robust and scalable condensation enhancement method where a high heat transfer coefficient is achieved by leveraging capillary forces within a high thermal conductivity porous wick to promote condensate removal. The capillary pressure is supported by a pump to sustain steady condensate removal, and the high thermal conductivity of the wick decreases the overall thermal resistance. This technique has the potential to enhance condensation for a variety of fluids including low surface tension fluids and is capable of operating in both a gravity and a micro- (or zero-) gravity environment. We highlight key characteristics and enhancements achieved through this capillary-enhanced filmwise condensation technique using a porous media flow model. The model results indicate that increased wick thickness and permeability increase the operational envelope and delay the failure that occurs when the condensate floods the wick. However, increasing the permeability is more favorable as both the heat transfer coefficient and the flooding threshold are increased. The working fluid thermophysical properties determine both the degree of enhancement possible and the relative contributions from gravitational and capillary pressure forces when condensation occurs in the presence of gravity. This study provides fundamental insight into an enhanced filmwise condensation technique and an improved framework for modeling porous media flows with mass addition via condensation.

17.
Ecol Evol ; 8(15): 7574-7587, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30151172

RESUMO

Floral foraging resources are valuable for pollinator conservation on farmland, and their provision is encouraged by agri-environment schemes in many countries. Across Europe, wildflower seed mixtures are widely sown on farmland to encourage pollinators, but the extent to which key pollinator groups such as solitary bees exploit and benefit from these resources is unclear. We used high-throughput sequencing of 164 pollen samples extracted from the brood cells of six common cavity-nesting solitary bee species (Osmia bicornis, Osmia caerulescens, Megachile versicolor, Megachile ligniseca, Megachile centuncularis and Hylaeus confusus) which are widely distributed across the UK and Europe. We documented their pollen use across 19 farms in southern England, UK, revealing their forage plants and examining the structure of their pollen transport networks. Of the 32 plant species included currently in sown wildflower mixes, 15 were recorded as present within close foraging range of the bees on the study farms, but only Ranunculus acris L. was identified within the pollen samples. Rosa canina L. was the most commonly found of the 23 plant species identified in the pollen samples, suggesting that, in addition to providing a nesting resource for Megachile leafcutter bees, it may be an important forage plant for these species. Higher levels of connectance and nestedness were characteristic of pollen transport networks on farms with abundant floral resources, which may increase resilience to species loss. Our data suggest that plant species promoted currently by agri-environment schemes are not optimal for solitary bee foraging. If a diverse community of pollinators is to be supported on UK and European farmland, additional species such as R. canina should be encouraged to meet the foraging requirements of solitary bees.

18.
J Crohns Colitis ; 12(7): 777-783, 2018 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-29648663

RESUMO

BACKGROUND AND AIMS: Patients with inflammatory bowel disease [IBD] colitis are at increased risk for colorectal cancer [CRC]. We examined the proportion and most likely aetiology of potentially preventable postcolonoscopy CRCs [PCCRCs] in a population-based cohort. Furthermore, adherence to IBD surveillance guidelines was evaluated in both PCCRCs and the remainder of prevalent CRCs. METHODS: All IBD patients diagnosed from 1991 to 2011 in the South Limburg region of The Netherlands [i.e. IBDSL cohort] were included. CRC cases were cross-checked with the Dutch pathology database and cancer registry. PCCRCs were defined as cancers diagnosed within 6-60 months after a colonoscopy and were classified as attributable to 'inappropriate surveillance interval', 'inadequate bowel examination', 'incomplete resection', 'missed lesion' or 'newly developed cancer'. RESULTS: Twenty CRC cases were identified during 25,931 patient years of follow-up in 2,801 patients. The proportion of PCCRCs was 45.0%. Of these, 55.6% could be considered a 'missed lesion', while other possible aetiologies occurred only once. Considering both PCCRCs [n=9] and prevalent CRCs [n=11], ten were detected after publication of the surveillance guideline, but only three patients were enrolled. Moreover, 6 CRCs [30.0%] were detected before the recommended start of surveillance. CONCLUSIONS: In the IBDSL cohort, 45.0% of all CRCs were considered to be PCCRCs, mainly classified as missed lesions. Additionally, a large proportion of CRCs in our cohort were observed before a surveillance endoscopy was performed. Therefore, stringent adherence to IBD surveillance guidelines, improving endoscopy techniques and adjusting the surveillance program may lead to a decrease in CRC incidence.


Assuntos
Adenocarcinoma/epidemiologia , Adenocarcinoma/etiologia , Colonoscopia , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/etiologia , Fidelidade a Diretrizes/estatística & dados numéricos , Vigilância da População , Adenocarcinoma/classificação , Adenocarcinoma/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Neoplasias Colorretais/classificação , Neoplasias Colorretais/diagnóstico por imagem , Erros de Diagnóstico , Detecção Precoce de Câncer , Feminino , Humanos , Incidência , Doenças Inflamatórias Intestinais , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Guias de Prática Clínica como Assunto , Sistema de Registros
19.
Inflamm Bowel Dis ; 24(7): 1558-1565, 2018 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-29668998

RESUMO

Background: Patients with active ulcerative colitis (UC) failing conventional therapies are in need of rescue strategies. Due to the fact that accepted step-up therapy with biologicals is expensive and sometimes unavailable, alternative therapies are warranted. Methotrexate (MTX) and thioguanine (TG) have both been suggested as alternative maintenance strategies in conventional thiopurine failing UC patients. In this multicenter database study, we compared safety and effectiveness (drug-survival) of MTX and TG in UC patients. Methods: We collected data from the Parelsnoer database, a prospective Dutch national database consisting of inflammatory bowel disease patients from all university hospitals in The Netherlands. Additional data were collected from detailed chart review. Results: In total, 99 UC patients were included, of which 48 used TG, 43 used MTX, and 8 patients had a history of both TG and MTX use. In 12% of the patients, biological therapy had failed. Roughly 70% of the patients in both groups were able to continue therapy for over 1 year. Adverse events were noted in 33% of all the patients and were mainly elevated liver enzymes or gastrointestinal complaints. Twenty-eight patients (28%) continued therapy (15 TG, 13 MTX) without the need of escalation therapy (eg, corticosteroids, biologicals, or surgery). Drug survival curves of both drugs were comparable, just as the number of patients with sustained clinical benefit of therapy (P > 0.05). Conclusion: Both MTX and TG may be used and maintained as rescue therapy with sustained clinical benefit in one-third of the UC patients failing conventional therapies.


Assuntos
Colite Ulcerativa/tratamento farmacológico , Imunossupressores/uso terapêutico , Metotrexato/uso terapêutico , Tioguanina/uso terapêutico , Adulto , Bases de Dados Factuais , Quimioterapia Combinada , Tolerância a Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Países Baixos , Modelos de Riscos Proporcionais , Estudos Prospectivos , Indução de Remissão , Resultado do Tratamento
20.
Sci Rep ; 8(1): 540, 2018 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-29323200

RESUMO

Vapor condensation is routinely used as an effective means of transferring heat or separating fluids. Dropwise condensation, where discrete droplets form on the condenser surface, offers a potential improvement in heat transfer of up to an order of magnitude compared to filmwise condensation, where a liquid film covers the surface. Low surface tension fluid condensates such as hydrocarbons pose a unique challenge since typical hydrophobic condenser coatings used to promote dropwise condensation of water often do not repel fluids with lower surface tensions. Recent work has shown that lubricant infused surfaces (LIS) can promote droplet formation of hydrocarbons. In this work, we confirm the effectiveness of LIS in promoting dropwise condensation by providing experimental measurements of heat transfer performance during hydrocarbon condensation on a LIS, which enhances heat transfer by ≈450% compared to an uncoated surface. We also explored improvement through removal of noncondensable gases and highlighted a failure mechanism whereby shedding droplets depleted the lubricant over time. Enhanced condensation heat transfer for low surface tension fluids on LIS presents the opportunity for significant energy savings in natural gas processing as well as improvements in thermal management, heating and cooling, and power generation.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...