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Due to the high strength of carbon nanotubes (CNTs) significant effort has been devoted to incorporating them into fibers and composites. To maximize their potential in these areas, there must be strong interactions between the CNT structures and the matrix of the composite. For CNT yarn, progress in this area has been limited. In this work, we present a method for modifying CNT yarn which improves the apparent interfacial shear strength (IFSS) by up to 45 %, as measured by single yarn pullout testing. An ammonium peroxide mixture (APM) treatment method is used to modify the yarn, and this is followed by treatment with commercial sizing agents. A tensioned heat treatment method is also employed to limit the effect of APM treatment on strength and modulus. This method increased the specific modulus of CNT yarns by as much as 16 %. The combined heat and chemical treatments yield increases as high as 43 % in IFSS and 6 % in specific tensile modulus while tempering the decreases in specific tensile strength. The yarn is characterized by SEM, EDS and Raman spectroscopy to show surface carbon being removed from the yarn, seemingly without damaging the CNT structures in the yarn. The main mechanism for IFSS increase appears to be removal of non-graphitic material from the yarn and slight oxidation of the yarn surface. The increase seen in IFSS has the potential to improve the performance of CNT yarn/polymer matrix composites for aerospace applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Dissemination and implementation (D&I) science is the practice of taking evidence-based interventions and sustainably incorporating them into routine clinical practice. As a relatively young field, D&I techniques are underutilized in cardiothoracic surgery. This review offers an overview of D&I science from the context of the cardiothoracic surgeon. First, we provide a general introduction to D&I science and basic terminology that is used in the field. Second, to illustrate D&I techniques in a real-world example, we discuss a case study for implementing lung protective management strategies for lung donor optimization nationally. Finally, we discuss challenges to successful implementation that are unique to cardiothoracic surgery and give several examples of evidence-based interventions that have been poorly implemented into surgical practice. We also provide examples of successful D&I interventions—including deimplementation strategies—from other surgical subspecialties. We hope that this review offers additional tools for cardiothoracic surgeons to explore when introducing evidence-based interventions into routine practice. [Display omitted] [ABSTRACT FROM AUTHOR]

The bleeding risk in individuals with inherited bleeding disorders (IBDs) during exodontia is traditionally managed with perioperative coagulation factors and/or desmopressin, in conjunction with systemic and topical perioperative tranexamic acid and meticulous primary closure. Factor replacement is costly, requires specialist input, and carries a risk of developing factor VIII (FVIII) inhibitors. This prospective study was performed to determine whether the use of a standardized Floseal and anti-fibrinolytic protocol could reduce postoperative bleeding in patients with IBDs undergoing dental extraction, as compared to factor replacement. All patients >18 years old attending Queensland Haemophilia Centre between November 2014 and July 2019 who required dental extractions were referred to the Oral and Maxillofacial Unit. Patients were consented for intraoperative Floseal administration instead of factor replacement. All other operative measures remained the same. The bleed rate was assessed against a historical control cohort. There were 34 extraction events in 32 patients. Four of the patients reported postoperative bleeding requiring factor supplementation or desmopressin; the bleeding rate was 11.8%. While not statistically significant, this was a reduction in the bleed rate compared to the traditional protocol (P = 0.35). Third molar extractions were 10.33 times more likely to cause postoperative bleeding (P = 0.018). The Floseal protocol was equipotent to the traditional perioperative factor replacement protocol. Floseal use is more economical, eliminates the risk of peri-procedural FVIII inhibitor development, and provides a haemostatic option for patients with very rare factor deficiencies, pre-existing clotting factor inhibitors, and those with anaphylaxis to clotting concentrates. [ABSTRACT FROM AUTHOR]

There is approximately a 2% risk of clinically significant VTE following temporary lower limb immobilisation after injury with an ankle immobilising plaster cast or boot. There is evidence that thromboprophylaxis for lower limb immobilised patients reduces the risk of VTE by approximately 50% but there is no international consensus as to which patients should receive thromboprophylaxis. The Plymouth VTE Risk Score was developed to identify patients at particular risk of VTE, in order to offer chemical prophylaxis to reduce their VTE risk. The score showed high completion rates, reliability and consistency. Using the Plymouth VTE Risk Score Version 3 (2014), we found an incidence of clinical VTE of 0.36% with 37.6% of patients being advised to have thromboprophylaxis. This is a lower VTE incidence than in most other studies of this patient group, which is of the order of 2 to 3%. The optimal RAM to use in clinical practice is yet to be defined, further clinical research is needed to accurately stratify patient risk and to define optimal risk treatment levels. We suggest research should focus on comparative clinical studies of risk assessment models. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs) have been widely researched in recent years, mainly to investigate their potential in various applications such as drug delivery, photocatalysis, and sensing. However, understanding of their fundamental properties, including physical and electronic structure, has lagged behind their development in applied sciences. To address this, it is necessary to use novel methods which go beyond the current level of characterization in the literature. In this work, we utilize time of flight-secondary ion mass spectrometry (ToF-SIMS) to generate specific knowledge of the structural components of three CDs generated in our lab. This work revealed that black CDs (B-CDs) possess a highly carbonic structure with nitrogen and oxygen functionalization throughout the particle structure. Carbon nitride dots (CNDs) possess some of these same carbonic structures, but also show the presence of more organic structures which would be expected through a bottom-up approach. In terms of carbonization, CNDs lie between B-CDs and the third sample, yellow-CDs (Y-CDs). Y-CDs are believed to be almost completely polymeric/organic in structure and the groups detected through this mass analysis supports this idea. The structural information from ToF-SIMS is compared with other structural techniques. Additionally, the optical properties of CDs before and after oxidation and reduction are used to craft a proposed photoluminescence (PL) mechanism for each system. The analysis contained herein enables further understanding of the structure of these three samples, and the attained understanding of the surface structure is particularly important for future biomedical applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Since their discovery, carbon dots (CDs) have been a promising nanomaterial in a variety of fields including nanomedicine. Despite their potential in this area, there are many obstacles to overcome for CDs to be approved for biomedical use. One major hindrance to CDs' approval is related to their poorly defined structure. Herein a structural study of CDs is presented in order to rectify this shortcoming. The properties of three CDs which have significant promise in biomedical applications, black CDs (B-CDs), carbon nitride dots (CNDs), and yellow CDs (Y-CDs), are compared in order to develop a coherent structural model for each nanosystem. Absorption coefficients were measured for each system and this data gave insight on the level of disorder in each system. Furthermore, extensive structural characterization has been performed in order to derive structural information for each system. This data showed that B-CDs and CNDs are functionalized to a greater degree and are also more disordered and amorphous than Y-CDs. These techniques were used to develop a structural model consistent with the obtained data and what is known for carbonic nanostructures. These models can be used to analyze CD emission properties and to better understand the structure-property relationship in CDs. This graphic illustrates the stark distinction in properties between certain carbon dots (CDs). This work highlights the large diversity of properties among CDs and endeavors to go beyond the spherical shape typically associated with this material to see the core structure and understand the formation of CDs. Image 1 [ABSTRACT FROM AUTHOR]

Graphical abstract Summary of tryptophan carbon dots (CDs) hydrothermal preparation, purification through electrophoresis, and injection into zebrafish to assess the ability of tryptophan CDs to cross the blood-brain barrier. Highlights • Carbon dots were prepared which appear to have tryptophan moieties on the surface. • Tryptophan carbon dots showed bright photoluminescence (QY = 48%) and low toxicity. • Confocal microscopy shows carbon dots in the central nervous system of zebrafish. Abstract Drug traversal across the blood-brain barrier has come under increasing scrutiny recently, particularly concerning the treatment of sicknesses, such as brain cancer and Alzheimer's disease. Most therapies and medicines are limited due to their inability to cross this barrier, reducing treatment options for maladies affecting the brain. Carbon dots show promise as drug carriers, but they experience the same limitations regarding crossing the blood-brain barrier as many small molecules do. If carbon dots can be prepared from a precursor that can cross the blood-brain barrier, there is a chance that the remaining original precursor molecule can attach to the carbon dot surface and lead the system into the brain. Herein, tryptophan carbon dots were synthesized with the strategy of using tryptophan as an amino acid for crossing the blood-brain barrier via LAT1 transporter-mediated endocytosis. Two types of carbon dots were synthesized using tryptophan and two different nitrogen dopants: urea and 1,2-ethylenediamine. Carbon dots made using these precursors show excitation wavelength-dependent emission, low toxicity, and have been observed inside the central nervous system of zebrafish (Danio rerio). The proposed mechanism for these carbon dots abilities to cross the blood-brain barrier concerns residual tryptophan molecules which attach to the carbon dots surface, enabling them to be recognized by the LAT1 transporter. The role of carbon dots for transport open promising avenues for drug delivery and imaging in the brain. [ABSTRACT FROM AUTHOR]

Highlights • This is the first case of Balamuthia mandrillaris brain infection suspected from nasal lavage. • Improper nasal lavage has been reported as the route of infection for Naegleria fowleri. • We suggest amoeba testing in cases of a nasal sore and ring-enhancing brain lesion. Abstract We report the case of a 69-year-old female who presented with a chronic nasal skin rash, new onset focal seizure, and a cerebral ring-enhancing lesion after a year of improper nasal irrigation. Despite aggressive and novel anti-amoebic treatment, she died as a result of a Balamuthia mandrillaris brain infection. [ABSTRACT FROM AUTHOR]

The Black Hills State University Underground Campus (BHUC) houses a low background counting facility on the 4850′ level of the Sanford Underground Research Facility. There are currently four ultra-low background, high-purity germanium detectors installed in the BHUC and it is anticipated four more detectors will be installed within a year. In total, the BHUC will be able to accommodate up to twelve detectors with space inside a class 1000 cleanroom, an automated liquid nitrogen fill system, on-site personnel assistance and other required utilities. [ABSTRACT FROM AUTHOR]

Study Objective: Surgical management of tubal factor infertility has largely been replaced by in vitro fertilization (IVF). Trainees now have little exposure to surgical techniques such as fimbrioplasty and tubal reanastomosis. This study compares the cost-effectiveness of tubal surgery and IVF for tubal factor infertility. This comprehensive analysis includes costs and probabilities from the infertility treatments themselves to adverse birth outcomes depending on the mode of conception. This cost-effectiveness analysis compares surgery and IVF in decision trees for hydrosalpinx, proximal obstruction, endometriosis, and previous sterilization. Clinical probabilities and effectiveness were derived from published literature. Estimated costs were taken from the reimbursements from five major third party payers to a major teaching hospital. Analysis was performed with TreeAge Pro Healthcare 2020 for Windows. N/A N/A N/A Our initial analysis includes tubal factor infertility caused by hydrosalpinx, proximal occlusion, endometriosis, and prior sterilization. Fimbrioplasty for hydrosalpinges with mild pathophysiological changes was more cost-effective than IVF. Fimbrioplasty for hydrosalpinges with advanced changes cost less than IVF, but were not very effective. Likewise, surgical repair of proximal occlusions was more cost-effective than IVF despite the failure rates of these procedures. Laparoscopic excision of endometriosis demonstrated more cost-effectiveness than IVF at all stages of disease. However, with higher maternal age and severe disease that makes ovarian dysfunction an overriding infertility factor, IVF is more cost-effective. Tubal reanastomosis was more cost-effective than IVF for patients <40 years old. Sensitivity analyses validated these findings across a wide range of effectiveness estimates as well as costs per procedure. Surgical intervention should be considered as a viable alternative for tubal factor infertility treatment in certain cases. Continued training in tubal surgery should be encouraged in both residency and fellowships. [ABSTRACT FROM AUTHOR]

Due to the numerous failed clinical trials of anti-amyloid drugs, microtubule associated protein tau (MAPT) now stands out as one of the most promising targets for AD therapy. In this study, we report for the first time the structure-dependent MAPT aggregation inhibition of carbon nitride dots (CNDs). CNDs have exhibited great promise as a potential treatment of Alzheimer's disease (AD) by inhibiting the aggregation of MAPT. In order to elucidate its structure-activity relationship, CNDs were separated via column chromatography and five fractions with different structures were obtained that were characterized by multiple spectroscopy methods. The increase of surface hydrophilic functional groups is consistent with the increase of polarity from fraction 1 to 5. Particle sizes (1–2 nm) and zeta potentials (∼-20 mV) are similar among five fractions. With the increase of polarity from fraction 1 to 5, their MAPT aggregation inhibition capacity was weakened. This suggests hydrophobic interactions between CNDs and MAPT, validated via molecular dynamics simulations. With a zebrafish blood-brain barrier (BBB) model, CNDs were observed to cross the BBB through passive diffusion. CNDs were also found to inhibit the generation of multiple reactive oxygen species, which is an important contributor to AD pathogenesis. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Correct use of Computational Fluid Dynamics (CFD) tools is essential in order to have confidence in the results. A comprehensive set of Best Practice Guidelines (BPG) in numerical simulations for Fuel Cells and Hydrogen applications has been one of the main outputs of the SUSANA project. These BPG focus on the practical needs of engineers in consultancies and industry undertaking CFD simulations or evaluating CFD simulation results in support of hazard/risk assessments of hydrogen facilities, as well as on the needs of regulatory authorities. This contribution presents a summary of the BPG document. All crucial aspects of numerical simulations are addressed, such as selection of the physical models, domain design, meshing, boundary conditions and selection of numerical parameters. BPG cover all hydrogen safety relative phenomena, i.e. release and dispersion, ignition, jet fire, deflagration and detonation. A series of CFD benchmarking exercises are also presented serving as examples of appropriate modelling strategies. Highlights • Best Practice Guidelines for H 2 safety simulations were developed for the first time. • BPG cover the whole range of phenomena such as dispersion, ignition and explosion. • All crucial aspects of numerical simulations are addressed. • CFD benchmarking exercises demonstrating proper modelling strategies are presented. [ABSTRACT FROM AUTHOR]

The “SUpport to SAfety aNAlysis of Hydrogen and Fuel Cell Technologies (SUSANA)” project aims to support stakeholders using Computational Fluid Dynamics (CFD) for safety engineering design and assessment of FCH systems and infrastructure through the development of a model evaluation protocol. The protocol covers all aspects of safety assessment modelling using CFD, from release, through dispersion to combustion (self-ignition, fires, deflagrations, detonations, and Deflagration to Detonation Transition - DDT) and not only aims to enable users to evaluate models but to inform them of the state of the art and best practices in numerical modelling. The paper gives an overview of the SUSANA project, including the main stages of the model evaluation protocol and some results from the on-going benchmarking activities. [ABSTRACT FROM AUTHOR]