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The perovskite solar cell has commercial potential due to the low-cost of materials and manufacturing processes with cell efficiencies on par with traditional technologies. Nanomaterials have many properties that make them attractive for the perovskite devices, including low-cost inks, low temperature processing, stable material properties and good charge transport. In this feature article, the use of nanomaterials in the hole transport and electron transport layers are reviewed. Specifically, SnO2 and NiOx are the leading materials with the most promise for translation to large scale applications. The review includes a discussion of the synthesis, formulation, and processing of these nanoparticles and provides insights for their further deployment towards commercially viable perovskite solar cells.
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BACKGROUND: Cognitive behavioural therapy (CBT) is an effective treatment for depression but a significant minority of clients do not complete therapy, do not respond to it, or subsequently relapse. Non-responders, and those at risk of relapse, are more likely to have adverse childhood experiences, early-onset depression, co-morbidities, interpersonal problems and heightened risk. This is a heterogeneous group of clients who are currently difficult to treat. AIM: The aim was to develop a CBT model of depression that will be effective for difficult-to-treat clients who have not responded to standard CBT. METHOD: The method was to unify theory, evidence and clinical strategies within the field of CBT to develop an integrated CBT model. Single case methods were used to develop the treatment components. RESULTS: A self-regulation model of depression has been developed. It proposes that depression is maintained by repeated interactions of self-identity disruption, impaired motivation, disengagement, rumination, intrusive memories and passive life goals. Depression is more difficult to treat when these processes become interlocked. Treatment based on the model builds self-regulation skills and restructures self-identity, rather than target negative beliefs. A bespoke therapy plan is formed out of ten treatment components, based on an individual case formulation. CONCLUSIONS: A self-regulation model of depression is proposed that integrates theory, evidence and practice within the field of CBT. It has been developed with difficult-to-treat cases as its primary purpose. A case example is described in a concurrent article (Barton et al., 2022) and further empirical tests are on-going.
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Terapia Cognitivo-Comportamental , Autocontrole , Humanos , Depressão/terapia , Terapia Cognitivo-Comportamental/métodos , Comorbidade , Resultado do Tratamento , RecidivaRESUMO
A series of nickel oxide (NiOx) inks, in the perovskite antisolvent chlorobenzene (CB) containing 15% ethanol, were prepared for the fabrication of p-i-n perovskite solar cells by blade coating. The inks included triethylamine (Et3N) and alkyl xanthate salts as ligands to disperse NiOxparticle aggregates and stabilize suspension. A total of four inks were evaluated: 0X (Et3N with no alkyl xanthate), 4X (Et3N + potassiumn-butyl xanthate), 12X (Et3N + potassiumn-dodecyl xanthate), and 18X (Et3N + potassiumn-octadecyl xanthate). The inks were characterized by UV-visible spectroscopy and FT-IR spectroscopy and the resulting films analyzed by thermogravimetry and scanning electron microscopy. Devices prepared using the 0X ink resulted in a peak power conversion efficiency (PCE) of 14.47% (0.25 cm2) and 9.96% (1 cm2). The 0X devices showed no significant loss of PCE after 100 days in a nitrogen flow box. Devices prepared with inks containing alkyl xanthate ligand had lower PCE that decreased with decreasing chain length, 18X > 12X > 4X.
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OBJECTIVES: To characterise the use of the parenteral non-steroidal anti-inflammatory drug parecoxib when given by continuous subcutaneous infusion (CSCI) in a hospice population. Clinical experience suggests parecoxib CSCI may be of benefit in this population, but empirical evidence in relation to its safety and efficacy is lacking. METHODS: Retrospective chart review of patients with a cancer diagnosis receiving parecoxib CSCI from 2008 to 2013 at the Marie Curie Hospice, Belfast. Data were collected on treatment regime, tolerability and, in patients receiving at least 7 days treatment, baseline opioid dose and changes in pain scores or opioid rescue medication requirements. RESULTS: Parecoxib CSCI was initiated in 80 patients with a mean administration of 17.9 days (median 11, range 1-94). When used for a period of 7 days, there was a statistically significant reduction in pain scores (p=0.002) and in the number of rescue opioid doses required (p=0.001), but no statistically significant opioid-sparing effect (p=0.222). It was generally well tolerated, although gastrointestinal, renal adverse effects and local site irritation were reported. CONCLUSIONS: Parecoxib may have a valuable place in the management of cancer pain, especially towards the end of life when oral administration is no longer possible and CSCI administration is relied on. Further studies into the efficacy and tolerability of parecoxib CSCI are merited.
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Anti-Inflamatórios não Esteroides/uso terapêutico , Dor do Câncer/tratamento farmacológico , Isoxazóis/uso terapêutico , Manejo da Dor , Adulto , Idoso , Analgésicos Opioides/uso terapêutico , Feminino , Cuidados Paliativos na Terminalidade da Vida , Hospitais para Doentes Terminais , Humanos , Infusões Subcutâneas , Masculino , Pessoa de Meia-Idade , Medição da Dor , Estudos Retrospectivos , Resultado do TratamentoRESUMO
The immune system is based on the actions of the collection of specialized immune defense cells and their secreted proteins and peptides that defend the host against infection by parasites. Parasites are organisms that live part or all of their lives in close physical association with the host and extract nutrients from the host and, by releasing toxins and virulence factors, cause disease with the potential for injury and premature death of that host. Parasites of the metazoa can be viruses, eubacteria, fungi, protozoans, and other metazoans. The immune system operates to kill or eliminate parasites and eliminate or detoxify their toxins and virulence factors. Although some of the elements of immune systems are specific to a particular phylum of metazoans, others show extensive evolutionary conservation, being present in several or all major phyla of the metazoa. The pentraxins display this latter character in their roles in immune defense. Pentraxins have been documented in vertebrates, nonvertebrate chordates, arthropods, and mollusks and may be present in other taxa of metazoans. Presumably the pentraxins appeared early in the evolution of metazoa, prior to their evolutionary divergence in the Precambrian epoch into many phyla present today, and have been preserved for the 542 million years since that explosive evolutionary radiation. The fidelity with which these phyla have preserved the pentraxins suggests that the functions of these proteins are important for survival of the members of these diverse taxa of animals.
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Proteína C-Reativa/fisiologia , Imunidade Inata/fisiologia , Imunoproteínas/fisiologia , Amiloide/sangue , Animais , Apoptose , Proteína C-Reativa/metabolismo , Evolução Molecular , Humanos , Sistema Imunitário , Lipopolissacarídeos/química , Neutrófilos/metabolismo , Ligação Proteica , Conformação Proteica , Streptococcus pneumoniae/metabolismoRESUMO
In addition to its roles in hemostasis and wound repair, the blood clot plays an underappreciated role in innate immunity, where the established clot serves as a barrier to microbial penetration into the internal milieu and where the early clot entraps and immobilizes microbes that have entered wounds to the integuments. In this report we document the behavior of the pathogenic gram-negative bacterium Vibrio harveyi that has been entrapped in the fabric of the extracellular blood clot of one of its target organisms, the Pacific white shrimp, Litopenaeus vannamei. The freshly entrapped bacteria are held tightly by the clot, losing even Brownian motility, but by 1 h post-entrapment, a fraction of the bacteria have established small domains of fibrinolysis that enlarge progressively, enabling bacteria to escape from the clot's embrace. Escape is dependent on the actions of both serine- and metallo-proteases released from the bacterial cells.
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Coagulação Sanguínea/imunologia , Imunidade Inata , Penaeidae/imunologia , Penaeidae/microbiologia , Vibrio/fisiologia , Animais , Ferimentos e Lesões/microbiologiaRESUMO
In vertebrates and arthropods, blood clotting involves the establishment of a plug of aggregated thrombocytes (the cellular clot) and an extracellular fibrillar clot formed by the polymerization of the structural protein of the clot, which is fibrin in mammals, plasma lipoprotein in crustaceans, and coagulin in the horseshoe crab, Limulus polyphemus. Both elements of the clot function to staunch bleeding. Additionally, the extracellular clot functions as an agent of the innate immune system by providing a passive anti-microbial barrier and microbial entrapment device, which functions directly at the site of wounds to the integument. Here we show that, in addition to these passive functions in immunity, the plasma lipoprotein clot of lobster, the coagulin clot of Limulus, and both the platelet thrombus and the fibrin clot of mammals (human, mouse) operate to capture lipopolysaccharide (LPS, endotoxin). The lipid A core of LPS is the principal agent of gram-negative septicemia, which is responsible for more than 100,000 human deaths annually in the United States and is similarly toxic to arthropods. Quantification using the Limulus Amebocyte Lysate (LAL) test shows that clots capture significant quantities of LPS and fluorescent-labeled LPS can be seen by microscopy to decorate the clot fibrils. Thrombi generated in the living mouse accumulate LPS in vivo. It is suggested that capture of LPS released from gram-negative bacteria entrapped by the blood clot operates to protect against the disease that might be caused by its systemic dispersal.
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Coagulação Sanguínea , Fibrina/fisiologia , Caranguejos Ferradura/imunologia , Lipopolissacarídeos/imunologia , Lipoproteínas/fisiologia , Tromboplastina/fisiologia , Animais , Fibrina/metabolismo , Humanos , Lipoproteínas/sangue , Camundongos , Especificidade da Espécie , Tromboplastina/metabolismo , Trombose/microbiologiaRESUMO
Instantaneous and average energy dissipation distributions in the nanoscale due to short and long range interactions are described. We employ both a purely continuous and a semi-discrete approach to analyze the consequences of this distribution in terms of rate of heat generation, thermal flux, adhesion hysteresis, viscoelasticity and atomic dissipative processes. The effects of peak values are also discussed in terms of the validity of the use of average values of power and energy dissipation. Analytic expressions for the instantaneous power are also derived. We further provide a general expression to calculate the effective area of interaction for fundamental dissipative processes and relate it to the energy distribution profile in the interaction area. Finally, a semi-discrete approach to model and interpret atomic dissipative processes is proposed and shown to lead to realistic values for the atomic bond dissipation and viscoelastic atomic processes.
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Multifrequency atomic force microscopy holds promise as a method to provide qualitative and quantitative information about samples with high spatial resolution. Here, we provide experimental evidence of the excitation of subharmonics in ambient conditions in the regions where capillary interactions are predicted to be the mechanism of excitation. We also experimentally decouple a second mechanism for subharmonic excitation that is highly independent of environmental conditions such as relative humidity. This implies that material properties could be mapped. Subharmonic excitation could lead to experimental determination of surface water affinity in the nanoscale whenever water interactions are the mechanism of excitation.
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INTRODUCTION: The delivery of high quality emergency medicine ideally involves input from senior doctors 24 h a day. This study aims to assess the influence of 'real-time' senior clinician supervision on patient disposition from a UK emergency department. METHODS: The study was set in a UK teaching hospital with 24 h senior cover. Patients were initially seen by a junior doctor who completed a plan for the patient before seeking senior advice. Primary outcome measures were a change in patient outcome of discharge, admit, telephone speciality for opinion or outpatient follow-up. RESULTS: 556 patients underwent senior review during the study period. Review reduced inpatient admissions by 11.9% (95% CI 7.2% to 18.2%) and specifically reduced admissions to the acute medical assessment unit by 21.2% (95% CI 13.5% to 30.8%). Inappropriate discharge was prevented in 9.4% (95% CI 6.2% to 13.7%) and appropriate use of outpatient facilities resulted in a rise of 34.6% in appointments. CONCLUSIONS: Senior doctor input in patient care in the ED adds accuracy to disposition decisions, impacting on patient safety and improving departmental flow.
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Auditoria Clínica , Serviço Hospitalar de Emergência/normas , Corpo Clínico Hospitalar/normas , Avaliação de Processos em Cuidados de Saúde/métodos , Hospitais de Ensino , Humanos , Alta do Paciente , Reino UnidoRESUMO
UNLABELLED: Emergency medicine has recently undergone significant changes, with training, staffing and service delivery attracting particular attention. Senior doctors are under increased pressure to ensure the prompt delivery of service and to provide a smooth patient journey. It has been suggested that junior trainees see fewer patients than their predecessors, resulting in the burden of clinical work being transferred to senior clinicians, representing a shift away from the traditional model of service delivery. This study charts the work rate trends among junior doctors and the proportion of work performed by senior doctors over a 3-year period. RESULTS: The number of patients seen by junior trainees fell by 4% and was associated with a statistically significant 16.6% reduction in the mean number of patients seen per hour. The number of patients seen purely by senior clinicians increased to over 35%, in addition to reviewing those seen by junior trainees. This highlights reduced clinical exposure and productivity among juniors, but also shows the significant knock-on effect on the workload of senior clinicians. CONCLUSIONS: There will need to be an increase in the number of trained clinicians within emergency medicine to continue to deliver effective training and supervision and ensure a safe, good quality service to patients.
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Eficiência , Medicina de Emergência/educação , Serviço Hospitalar de Emergência , Corpo Clínico Hospitalar , Reino Unido , Recursos HumanosRESUMO
AIM: We aimed to quantify the impact of a raised preoperative ambient temperature (T(ambient)) on core temperature (T(core)) after induction of anesthesia in children. BACKGROUND: It has been suggested that prewarming of patients before anesthesia induction reduces postinduction drop in T(core). Neither the prewarming temperature nor its duration is established for adults or children. Nevertheless, it remains common practice to either warm the operating theatre and induction room or employ radiant heaters prior to induction of anesthesia, particularly for infants and neonates. We aimed to quantify the benefit, if any, of this warming practice. METHODS: We conducted a prospective clinical study to assess T(core) behavior in children randomized to either raised or standard ambient temperature as a prewarming technique prior to induction and until the operation commenced. We have called this 'preoperative' warming. Well, children scheduled for elective surgery where presurgical anesthetic duration exceeded 20 min were randomized to a T(ambient) of either 26 or 21 degrees C. Esophageal temperature was monitored continuously until the operative procedure commenced. RESULTS: There were 30 children in each group. Those in the warmed group (26 degrees C) had a statistically significant higher initial T(core) (0.4 degrees C warmer) and less drop in their T(core) (0.18 degrees C benefit at 20 min). Although younger/lighter/shorter individuals were more likely to drop their T(core), a warmer T(ambient) had only 0.1 degrees C thermal benefit irrespective of age. CONCLUSIONS: There are statistically significant thermal advantages to preoperative environmental warming. This study provides data to assist the anesthetist in deciding when these are likely to be clinically relevant.
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Anestesia , Temperatura Corporal/fisiologia , Cuidados Pré-Operatórios/métodos , Adolescente , Anestesia Caudal , Peso Corporal , Criança , Pré-Escolar , Determinação de Ponto Final , Esôfago/fisiologia , Feminino , Humanos , Lactente , Modelos Lineares , Masculino , Estudos Prospectivos , Caracteres Sexuais , Temperatura , Membrana Timpânica/fisiologiaRESUMO
BACKGROUND: Surgisis and AlloDerm, two biosynthetic materials, have been previously used with success in abdominal wall repairs in the setting of contaminated fields. Historically, Vicryl Woven Mesh, a synthetic material, has also been used in such settings as a temporary bridge for abdominal wall reconstruction. This study compares Surgisis and AlloDerm with Vicryl Woven Mesh with respect to tensile strength, collagen remodeling, and neovascularization using a rat hernia model. METHODS: A prospective randomized trial of 54 Sprague-Dawley rats were assigned to the Surgisis, AlloDerm, or Vicryl Woven Mesh group with baseline, 30-day, and 60-day end points. A 1.5-cm x 5.0-cm defect was created in the right abdominis rectus muscle and repaired with an underlay bridge graft using the different treatment materials. Tensile strength was measured using an Instron tensiometer. Histologic specimens were evaluated for neovascularization, collagen deposition, and collagen organization at the 30- and 60-day time points. RESULTS: Surgisis had significantly greater tensile strength compared to Vicryl Woven Mesh at the baseline time point (0.142 vs. 0.091 MPa, p < 0.05). There were no differences between groups tensile strength at 30 or 60 days postoperatively. The Vicryl Woven Mesh and AlloDerm groups showed increases in tensile strength at 30 days postoperatively versus baseline (p < 0.05). Vicryl Woven Mesh, Surgisis, and AlloDerm all showed increases in tensile strength at 60 days postoperatively compared to 30 days postoperatively and at baseline (p < 0.05). Surgisis and AlloDerm had significantly greater (p < 0.05) amounts of collagen deposition and organization at 30 and 60 days compared to Vicryl Woven Mesh. There was no significant difference between AlloDerm and Surgisis with respect to collagen deposition and organization. Surgisis and AlloDerm showed a significantly greater amount (p < 0.05) of neovascularization than Vicryl Woven Mesh at both time points. In addition, Surgisis had a significantly greater amount (p < 0.05) of neovascularization than AlloDerm at both 30 and 60 days. CONCLUSION: Surgisis has increased baseline tensile strength compared to Vicryl Woven Mesh. Tensile strength in Vicryl Woven Mesh is equal to biosynthetic grafts after tissue incorporation. Biosynthetic grafts showed superior collagen deposition and organization. Surgisis mesh showed increased neovascularization over both AlloDerm and Vicryl Woven Mesh.
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Parede Abdominal/patologia , Parede Abdominal/cirurgia , Colágeno/uso terapêutico , Poliglactina 910/uso terapêutico , Telas Cirúrgicas , Suturas , Animais , Materiais Biocompatíveis , Colágeno/administração & dosagem , Modelos Animais de Doenças , Masculino , Poliglactina 910/administração & dosagem , Ratos , Ratos Sprague-Dawley , Resistência à TraçãoRESUMO
Fibromuscular dysplasia is a rare vascular disease that is characterized as nonatherosclerotic and noninflammatory in nature. This disease most commonly afflicts the renal and cerebrovascular beds but can rarely affect the upper extremity. We present the case of a 76-year-old woman who complained of a symptom complex, congruent with Raynaud's phenomenon on the right side. The patient had evidence of distal ischemia without the classic angiographic evidence of fibromuscular dysplasia on arteriography. The abnormal arterial section of the right brachial artery was resected and grafted with reversed saphenous vein. She has had no reoccurrence of her symptoms and no stenosis of her graft over a 3-year follow-up period.
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Artéria Braquial/cirurgia , Displasia Fibromuscular/cirurgia , Veia Safena/transplante , Procedimentos Cirúrgicos Vasculares , Adulto , Idoso , Angioplastia com Balão , Artéria Braquial/diagnóstico por imagem , Artéria Braquial/patologia , Feminino , Displasia Fibromuscular/diagnóstico por imagem , Displasia Fibromuscular/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Resultado do TratamentoRESUMO
Cerebral air embolism occurs very seldom as a complication of central venous catheterization. We report a 57-year-old female with cerebral air embolism secondary to removal of a central venous catheter (CVC). The patient was treated with supportive measures and recovered well with minimal long-term injury. The prevention of air embolism related to central venous catheterization is discussed.
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Cateterismo Venoso Central/efeitos adversos , Remoção de Dispositivo/efeitos adversos , Embolia Aérea/etiologia , Embolia Intracraniana/etiologia , Edema Encefálico , Embolia Aérea/prevenção & controle , Embolia Aérea/terapia , Feminino , Humanos , Embolia Intracraniana/prevenção & controle , Embolia Intracraniana/terapia , Pessoa de Meia-Idade , Oxigenoterapia , Acidente Vascular CerebralRESUMO
The serum-amyloid-P-component-like pentraxin from Limulus polyphemus, a recently discovered pentraxin species and important effector protein of the hemolymph immune system, displays two distinct doubly stacked cyclic molecular aggregations, heptameric and octameric. The refined three-dimensional structures determined by X-ray crystallography, both based on the same cDNA sequence, show that each aggregate is constructed from a similar dimer of protomers, which is repeated to make up the ring structure. The native octameric form has been refined at a resolution of 3 A, the native heptameric form at 2.3 A, and the phosphoethanolamine (PE)-bound octameric form at 2.7 A. The existence of the hitherto undescribed heptameric form was confirmed by single-particle analysis using cryo-electron microscopy. In the native structures, the calcium-binding site is similar to that in human pentraxins, with two calcium ions bound in each subunit. Upon binding PE, however, each subunit binds a third calcium ion, with all three calcium ions contributing to the binding and orientation of the bound phosphate group within the ligand-binding pocket. While the phosphate is well-defined in the electron density, the ethanolamine group is poorly defined, suggesting structural and binding variabilities of this group. Although sequence homology with human serum amyloid P component is relatively low, structural homology is high, with very similar overall folds and a common affinity for PE. This is due, in part, to a "topological" equivalence of side-chain position. Identical side chains that are important in both function and fold, from different regions of the sequence in human and Limulus structures, occupy similar space within the overall subunit fold. Sequence and structure alignment, based on the refined three-dimensional structures presented here and the known horseshoe crab pentraxin sequences, suggest that adaptation and refinement of C-reactive-protein-mediated immune responses in these ancient creatures lacking antibody-based immunity are based on adaptation by gene duplication.