RESUMO
Evaluation of metal-organic frameworks (MOFs) for adsorbed natural gas (ANG) technology employs pure methane as a surrogate for natural gas (NG). This approximation is problematic, as it ignores the impact of other heavier hydrocarbons present in NG, such as ethane and propane, which generally have more favorable adsorption interactions with MOFs compared to methane. Herein, using quantitative Raman spectroscopic analysis and Monte Carlo calculations, we demonstrate the adsorption selectivity of high-performing MOFs, such as MOF-5, MOF-177, and SNU-70, for a methane and ethane mixture (95:5) that mimics the composition of NG. The impact of selectivity on the storage and deliverable capacities of these adsorbents during successive cycles of adsorption and desorption, simulating the filling and emptying of an ANG tank, is also demonstrated. The study reveals a gradual reduction in the storage performance of MOFs, particularly with smaller pore volumes, due to ethane accumulation over long-term cycling, until a steady state is reached with substantially degraded storage performance.
RESUMO
Metal-organic frameworks (MOFs) are demonstrated to be readily activated by treatment with the low surface tension, low boiling point solvent dimethyl ether (DME). The mildness of the method enables access to high surface areas by avoiding structural changes in the framework that often plague thermal activation methods. A distinction from previous methods is that DME activation succeeds for materials with coordinatively unsaturated sites (CUS) and non-CUS MOFs as well. DME displaces solvent molecules occupying the pores of the MOF as well as those coordinated to metal centers; reducing evacuation temperature by using a coordinating, yet highly volatile guest enables low temperature activation with structural retention as demonstrated surface area measurements that match or exceed existing activation protocols.
RESUMO
DNA-based FluoroCubes were recently developed as a solution to photobleaching, a ubiquitous limitation of fluorescence microscopy (Niekamp; ; Stuurman; ; Vale Nature Methods, 2020). FluoroCubes, that is, compact â¼4 × 4 × 5.4 nm3 four-helix bundles coupled to ≤6 fluorescent dyes, remain fluorescent up to â¼50× longer than single dyes and emit up to â¼40× as many photons. The current work answers two important questions about the FluoroCubes. First, what is the mechanism by which photostability is enhanced? Second, are FluoroCubes compatible with Förster resonance energy transfer (FRET) and similar techniques? We use single particle photobleaching studies to show that photostability arises through interactions between the fluorophores and the four-helix DNA bundle. Supporting this, we discover that smaller â¼4 × 4 × 2.7 nm3 FluoroCubes also confer ultraphotostability. However, we find that certain dye-dye interactions negatively impact FluoroCube performance. Accordingly, 4-dye FluoroCubes lacking these interactions perform better than 6-dye FluoroCubes. We also demonstrate that FluoroCubes are compatible with FRET and dark quenching applications.
Assuntos
Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes , DNA , Transferência Ressonante de Energia de Fluorescência/métodos , Microscopia de Fluorescência/métodos , FotodegradaçãoRESUMO
The synthesis of MOF-74 (MOF = metal-organic framework) proceeds first through the generation of chemically and topologically distinct materials, referred to as phases, displaying exclusively carboxylate coordination, followed by further deprotonation to enable oxo coordination and MOF-74 formation. The synthesis of Mg-MOF-74 at high concentrations of linker and metal enables the stabilization and characterization of the previously unobserved, exclusively carboxylate coordinating phases. Ex situ and in situ approaches are leveraged to provide the time-resolved observation of Mg-MOF-74 synthesis and the formation of phases that precede Mg-MOF-74 formation as well as metastable phase dissolution. These data support dissolution and redeposition as the mechanism of MOF-74 formation and provide insight into the formation mechanism of MOFs with multiple linker coordination types.
Assuntos
Estruturas Metalorgânicas , Estruturas Metalorgânicas/química , Metais/químicaRESUMO
Total photoreducible mercury [Hg(II)RED] and photoreduction rates in the surface waters of four lakes in Kejimkujik National Park, Nova Scotia were measured monthly over a summer. The percent of THg that was photoreducible [%Hg(II)RED] decreased significantly in two of the four lakes from early to late summer: North Cranberry (maximum 42% to minimum 14%) and Big Dam East (maximum 51% to minimum 6%). Hg(II)RED was found to have a linear relationship with THg for all combined site data. THg and Hg(II)RED were found to have positive linear relationships with DOC concentrations (R2 = 0.97; n = 36; p < 0.01 and R2 = 0.75; n = 36; p < 0.01, respectively). A smaller proportion of THg was found to be photoreducible with increasing DOC concentration.
Assuntos
Mercúrio , Poluentes Químicos da Água , Matéria Orgânica Dissolvida , Monitoramento Ambiental , Lagos , Mercúrio/análise , Estações do Ano , Poluentes Químicos da Água/análiseRESUMO
The ethos of the junior trainees' group is to facilitate peer support, an important complement to pursuing our speciality of oral and maxillofacial surgery. Launched in September 2020, the Buddy Scheme enables peer-matching. Results demonstrate this scheme has successfully provided additional support for second-degree applicants. With further help from our senior colleagues, our ambition is to expand this scheme in 2021.
Assuntos
Cirurgia Bucal , HumanosRESUMO
Venous thromboembolism (VTE), including both deep venous thrombosis (DVT) and pulmonary embolism (PE), is a major complication of musculoskeletal surgery in general, and the risk is heightened in musculoskeletal oncology surgery. Despite the well-known association between cancer and VTE, the mechanism promoting this pathology is not entirely well understood. It is estimated that nearly all cancer patients will experience from some form of VTE, whether or not clinically relevant, during the course of their disease. Nonetheless, numerous studies have analyzed the occurrence and prevention of VTE in patients with cardiovascular disease or suffering trauma, but very few have specifically examined the safety or efficacy of preventing VTE in cancer patients with metastatic skeletal disease. This review will examine the various types of prophylactic treatment, timing of administration, risk stratification for determining the appropriate course of anticoagulation (AC), and discuss current views on chemical prophylaxes relativity to wound complications and excessive bleeding in orthopedic oncology patients. Overall, careful choice of anticoagulant and timing of administration must be made in order to avoid bleeding complications. A risk stratification system to determine which chemical prophylaxis to administered could be beneficial in both reducing the occurrence of VTE and decreasing associated wound complications or mortality. Further study should be conducted to tailor chemical prophylaxes recommendations to this largely affected population and effectively reduce the occurrence of VTE.
Assuntos
Doença Diverticular do Colo , Diverticulite , Laparoscopia , Procedimentos Cirúrgicos Robóticos , Ureter , Diverticulite/cirurgia , Doença Diverticular do Colo/diagnóstico por imagem , Doença Diverticular do Colo/cirurgia , Fluorescência , Humanos , Ureter/diagnóstico por imagem , Ureter/cirurgiaRESUMO
Credentialing processes for surgeons seeking robotic thoracic surgical privileges are not evidence-based, and the learning curve has not been reported. The goal of this study is to review our experience with robotic lobectomies and provide evidence for the development of a more uniform credentialing process. We performed a retrospective review of the first 272 consecutive robotic lobectomies performed between 2011 and 2017 by a single surgeon with prior video-assisted thoracoscopic (VATS) experience. Primary outcomes were operative duration, blood loss, chest tube duration, length of hospital stay, intraoperative complication, and conversion to thoracotomy. The patients were subdivided by surgical date into two cohorts of 120 consecutive patients to compare differences in outcomes, thereby illustrating the learning curve. Between 2011 and 2017, 272 patients (median age 67.5 years) underwent a robotic lobectomy by a single surgeon. The majority of patients (157/272) had early stage (T1N0) adenocarcinoma. For the entire cohort, median operative time was 160 min (83-317 min). The median blood loss was 75 mL (10-4000 mL). Median chest tube duration was 2 days (1-23 days) and median hospital stay was 3 days (1-25 days). Intraoperative complications occurred in seven patients. Only six patients required conversion to thoracotomy. Using multivariable logistic regression, it was found that the age, gender, and stage do not factor into conversion to thoracotomy, but BMI was found to be a significant covariate (p 0.043). As the surgeon performs more surgeries, there is a significantly shorter operative time (p < 0.001), decreased blood loss (p < 0.001), and shorter hospital stay (p < 0.014). When the first 120 and last 120 surgeries were compared, there was significantly less blood loss (234.6 vs 78.69 cc, p < 0.001), shorter operative time (181.9 vs 147.4 min, p < 0.001), shorter tube duration (3.49 vs 3.11 days, p 0.007), and shorter length of stay (4.03 vs 3.48 days, p < 0.001), respectively. More intraoperative complications were observed during the first 120 surgeries (6/120) compared to the last 120 surgeries (0/120; Fischer exact p = 0.029). Regression model plots did not show any apparent and significant change points, but rather a steady improvement. The more cases the surgeon does, the better is the outcome in terms of operative duration, blood loss, post-operative length of stay and intraoperative complications. The learning curve for robotic surgery for a surgeon with prior VATS experience is that of a continuous improvement with experience instead of a particular change point. Since most thoracic surgeons who perform robotic-assisted surgery have already gotten past their VATS learning curves, they no longer have a definable learning curve for robotic surgery. Hence, if a surgeon is already proficient and credentialed to perform VATS lung resections, he or she is no longer faced with a significant learning curve for robotic lung resections, and should be credentialed to do so once he or she has undergone the appropriate training with the equipment and technology.
Assuntos
Adenocarcinoma/cirurgia , Credenciamento , Curva de Aprendizado , Neoplasias Pulmonares/cirurgia , Pneumonectomia , Procedimentos Cirúrgicos Robóticos , Cirurgiões , Idoso , Perda Sanguínea Cirúrgica/estatística & dados numéricos , Conversão para Cirurgia Aberta/estatística & dados numéricos , Feminino , Humanos , Complicações Intraoperatórias/epidemiologia , Tempo de Internação , Masculino , Duração da Cirurgia , Estudos Retrospectivos , Cirurgia Torácica Vídeoassistida , Resultado do TratamentoRESUMO
BACKGROUND Community engagement is believed to be an important component of quality primary health care. We aimed to capture specific examples of community engagement by general practices, and to understand the barriers that prevent engagement. METHODS We conducted 20 distinct interviews with 31 key informants from general practice and the wider community. The interviews were semi-structured around key relevant topics and were analysed thematically. RESULTS Key themes identified from the interview transcripts included an understanding of 'community', examples of community engagement and the perceived benefits and barriers to community-engaged general practice. We particularly explored aspects of community engagement with Maori. CONCLUSIONS General practices in the study do not think in terms of communities, and they do not have a systematic framework for engagement. Although local champions have generated some great initiatives, most practices seemed to lack a conceptual framework for engagement: who to engage with, how to engage with them, and how to evaluate the results of the engagement.
Assuntos
Participação da Comunidade/métodos , Medicina Geral/organização & administração , Atenção Primária à Saúde/organização & administração , Feminino , Medicina Geral/normas , Humanos , Entrevistas como Assunto , Masculino , Havaiano Nativo ou Outro Ilhéu do Pacífico/psicologia , Nova Zelândia , Atenção Primária à Saúde/normas , Pesquisa Qualitativa , Qualidade da Assistência à Saúde/organização & administraçãoRESUMO
Teleost fishes evolved livebearing via egg retention 14 times. Matrotrophy has evolved within 12 of those lineages. By contrast, squamate reptiles evolved livebearing over 115 times, but only two to four of those lineages are known to have evolved matrotrophy. Is the discrepancy between these organisms in the probability of this transition caused by differences in their eggs? We show that the eggs of oviparous species in the superorder Atherinomorpha can acquire small organic molecules from their surrounding environment against a concentration gradient via mechanisms of active transport. Uptake rates were inhibited by competing radiolabelled amino acids against unlabelled versions of themselves. Transport was non-specific as uptake rates were similar for l-leucine and its biologically uncommon enantiomer d-leucine. Eggs are also capable of transporting larger microspheres across the membrane, but transport is inhibited at temperatures below 4°C, suggesting active transport occurs via pinocytosis. Conflict theory predicts that the ability of the egg to acquire maternal resources will facilitate the embryo-parent arms race that leads to the evolution of matrotrophy following the transition to livebearing. The shelled eggs of amniotes lack such access to maternal resources when retained in the evolution of viviparity.
Assuntos
Adaptação Biológica , Evolução Biológica , Ciprinodontiformes/fisiologia , Óvulo/fisiologia , Viviparidade não Mamífera , Aminoácidos/metabolismo , Animais , Feminino , PinocitoseRESUMO
Essentials Research suggests that intensive treatment episodes may increase the risk to develop inhibitors. We performed an international nested case-control study with 298 non-severe hemophilia A patients. Surgery and a high dose of factor VIII concentrate were associated with increased inhibitor risk. Physicians need to review arguments for factor VIII dose and elective surgery extra critically. SUMMARY: Background Inhibitor development is a major complication of treatment with factor VIII concentrates in hemophilia. Findings from studies among severe hemophilia A patients suggest that intensive treatment episodes increase the risk of developing inhibitors. Objectives We set out to assess whether intensive treatment is also associated with an increased risk of inhibitor development among non-severe hemophilia A patients. Patients/Methods We performed a nested case-control study. A total of 75 inhibitor patients (cases) and 223 control patients were selected from 2709 non-severe hemophilia A patients (FVIII:C, 2-40%) of the INSIGHT cohort study. Cases and controls were matched for date of birth and cumulative number of exposure days (EDs) to FVIII concentrates. Conditional logistic regression was used to calculate both unadjusted and adjusted odds ratios (aOR); the latter were adjusted for a priori specified confounders. Results Peak treatment of 5 or 10 consecutive EDs did not increase inhibitor risk (aOR, 1.0; 95% confidence interval (CI), 0.4-2.5; and aOR, 1.8; CI, 0.6-5.5, respectively). Both surgical intervention (aOR, 4.2; CI, 1.7-10.3) and a high mean dose (> 45 IU kg-1 /ED) of FVIII concentrate (aOR, 7.5; CI, 1.6-35.6) were associated with an increased inhibitor risk. Conclusions Our findings suggest that high-dose FVIII treatment and surgery increase the risk of inhibitor development in non-severe hemophilia A. Together with the notion that non-severe hemophilia A patients are at a lifelong risk of inhibitor development, we suggest that in the future physicians will review the arguments for the FVIII dose and elective surgery extra critically.
Assuntos
Fator VIII/imunologia , Fator VIII/uso terapêutico , Hemofilia A/sangue , Hemofilia A/imunologia , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Pré-Escolar , Estudos de Coortes , Fator VIII/antagonistas & inibidores , Humanos , Cooperação Internacional , Pessoa de Meia-Idade , Razão de Chances , Análise de Regressão , Fatores de Risco , Resultado do Tratamento , Adulto JovemRESUMO
Bone conduction headphones are devices that transmit sound through the bones of a listener's head rather than through the air in their outer ear. They have been marketed as a safer way to enjoy audio content while walking, jogging, or cycling. However, listening to distracting sounds over bone conduction may still disrupt a listener's awareness of their auditory environment. The present study investigated the nature of this interference with the faculty of sound source localization-a key prerequisite for generating situation awareness through audio. Participants sat in the middle of a circle of loudspeakers and listened for target sounds played from different directions. Each time they heard a sound, they responded by indicating what direction they judged the sound to have come from. Meanwhile, participants listened to distractor sounds played through bone conduction headphones. Participants heard (1) no distractor sounds, (2) a spoken story that they were instructed to ignore, and (3) the same spoken story that they were instructed to attend to. For conditions (2) and (3), some participants heard a version of the story with background music, while others heard the spoken story without the music. Participants had greater localization error in the distractor-present conditions. Additionally, participants who heard the spoken story with music exhibited greater localization error. However, there was no effect of whether participants ignored or attended to distractors. This pattern was attributed to masking effects, and was more pronounced for narrow-band targets compared to broadband targets. Post-hoc analyses found evidence of a 'pulling' effect, in which localization judgments were systematically biased toward the apparent direction of the bone conducted distractors. These results indicate that using bone conduction headphones can be expected to cause a decline in a person's awareness of their environment, in a subtle way that a jogger or cyclist might not be actively aware of, even if their attention is directed to the environment and environmental sounds are readily detectible.
Assuntos
Atenção , Conscientização , Localização de Som , Adolescente , Adulto , Percepção Auditiva , Condução Óssea , Meio Ambiente , Feminino , Humanos , Masculino , Mascaramento Perceptivo , Análise e Desempenho de Tarefas , Adulto JovemRESUMO
In sexually reproducing organisms, the genetic interests of individuals are not perfectly aligned. Conflicts among family members are prevalent since interactions involve the transfer of limited resources between interdependent players. Intrafamilial conflict has traditionally been considered along three major axes: between the sexes, between parents and offspring, and between siblings. In these interactions, conflict is expected over traits in which the resulting phenotypic value is determined by multiple family members who have only partially overlapping fitness optima. We focus on four major categories of animal reproductive mode (broadcast spawning, egg laying, live bearing, and live bearing with matrotrophy) and identify the shared phenotypes or traits over which conflict is expected, and then review the empirical literature for evidence of their occurrence. Major transitions among reproductive mode, such as a shift from external to internal fertilization, an increase in egg-retention time, modifications of embryos and mothers for nutrient transfer, the evolution of postnatal parental care, and increased interaction with the kin network, mark key shifts that both change and expand the arenas in which conflict is played out.
Assuntos
Evolução Biológica , Conflito Psicológico , Relações Familiares/psicologia , Reprodução/fisiologia , Animais , Feminino , Humanos , MasculinoRESUMO
The Irish Heart Foundation carried out the Irish National Audit of Stroke Care (INASC) in 2008. Management practices were significantly poorer than those in the UK Sentinel audits. Since then an acute stroke unit has been established in University Hospital Limerick. A stroke database was established. 12 key indicators of stroke management audited by INASC were identified. Results were compared to those in INASC. 89 stroke patients were admitted. 8 of the 12 key indicators scored significantly better than in INASC. 92.5% had a brain scan within 24hrs (INASC-40%, p = < 0.001). 100% of ischaemic strokes received anti-thrombotics (INASC-85%, p = 0.001). 94% had rehab goals agreed by MDT (22% in INASC p = 0.0000). 55% were treated in stroke unit (2% in INASC, p = 0.0000). MDT input improved with regard to physiotherapy (87% vs 43% in INASC, p = < 0.02) and SALT (74% vs 26%, p = < 0.02). Stroke management has significantly improved from 2008, however some deficiencies remain.
Assuntos
Unidades Hospitalares/estatística & dados numéricos , Acidente Vascular Cerebral/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/administração & dosagem , Anticoagulantes/uso terapêutico , Aspirina/administração & dosagem , Aspirina/uso terapêutico , Deglutição , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neuroimagem , Inibidores da Agregação Plaquetária/administração & dosagem , Inibidores da Agregação Plaquetária/uso terapêutico , Estudos Prospectivos , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/fisiopatologiaAssuntos
Antidepressivos/uso terapêutico , Benzodiazepinas/uso terapêutico , Depressão , Idoso , Depressão/diagnóstico , Depressão/tratamento farmacológico , Erros de Diagnóstico/prevenção & controle , Uso de Medicamentos/estatística & dados numéricos , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Irlanda , MasculinoRESUMO
Diagnosis of type I von Willebrand Disease (VWD) can be challenging. In 2004, the United Kingdom Haemophilia Centre Doctors' Organisation (UKHCDO) proposed more stringent diagnostic criteria to replace the 1995 guidelines. To determine the true number of cases of type 1 VWD in a single paediatric centre, the 2004 UKHCDO Guideline for the diagnosis of VWD was used to evaluate 114 patients on our type 1 VWD register. Clinical and laboratory data were collected and analysed to see whether they met the criteria for type 1 VWD. Only 8% remained on the type 1 VWD register. 18% have been classified as 'possible type 1 VWD'. Twenty five surgical procedures have since been performed on patients from the group in which the diagnosis was removed without any haemostatic support or bleeding complications. Reaction to the removal of the VWD diagnosis or delivery of an alternative diagnosis was positive for most patients and families. This study is the first to assess the impact of the 2004 UKHCDO Guidelines on the diagnosis of VWD. It provides evidence that the prevalence of type 1 VWD may actually be closer to that of haemophilia instead of the previously reported 1-3% of the general population. We propose that all centres should review their patients with a diagnosis of VWD to revalidate this disease that claims to be our most common inherited bleeding disorder.
Assuntos
Testes Hematológicos/métodos , Guias de Prática Clínica como Assunto , Doença de von Willebrand Tipo 1/diagnóstico , Criança , Serviços de Saúde da Criança/normas , Pré-Escolar , Humanos , Anamnese , Estudos Retrospectivos , Reino Unido , Fator de von Willebrand/metabolismoRESUMO
Bipolar disorder (BP) is a debilitating psychiatric disorder, affecting â¼2% of the worldwide population, for which the etiological basis, pathogenesis, and neurocircuitry remain poorly understood. Individuals with BP suffer from recurrent episodes of mania and depression, which are commonly treated with the mood stabilizer lithium. However, nearly half of BP patients do not respond adequately to lithium therapy and the clinically relevant mechanisms of lithium for mood stabilization remain elusive. Here, we modeled lithium responsiveness using cellular assays of glycogen synthase kinase 3 (GSK-3) signaling and mood-related behavioral assays in inbred strains of mice that differ in their response to lithium. We found that activating AKT through phosphosrylation of a key regulatory site (Thr308) was associated with lithium response-activation of signaling pathways downstream of GSK-3 in cells and attenuation of mood-related behaviors in mice-and this response was attenuated by selective and direct inhibition of AKT kinase activity. Conversely, the expression of constitutively active AKT1 in both the cellular and behavioral assays conferred lithium sensitivity. In contrast, selective and direct GSK-3 inhibition by the ATP-competitive inhibitor CHIR99021 bypassed the requirement for AKT activation and modulated behavior in both lithium-responsive and non-responsive mouse strains. These results distinguish the mechanism of action of lithium from direct GSK-3 inhibition both in vivo and in vitro, and highlight the therapeutic potential for selective GSK-3 inhibitors in BP treatment.