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Under complex, dynamic loading conditions, damage can occur within a material. Should this damage not lead to catastrophic failure, the material can continue to sustain further loading. However, little is understood about how to represent the mechanical response of a material that has experienced dynamic loading leading to incipient damage. Here, this effect is examined in copper. Copper is shock loaded to impart an incipient state of damage to the material. Thereafter compression and tensile specimens were sectioned from the dynamically damaged specimen to quantify the subsequent properties of the material in the region of intense incipient damage and in regions far from the damage. It is observed that enhanced yield stresses result from the damaged material even over material, which has simply been shock loaded and not damaged. These results are rationalized in terms of stored plastic work due to the damage process.

Shear localization is often a failure mechanism in materials subjected to high strain rate deformation. It is generally accepted that the microstructure evolution during deformation and the resulting heterogeneities strongly influence the development of these shear bands. Information regarding the development of local mechanical heterogeneities during deformation is difficult to characterize and as such, constitute is a critical missing piece in current crystal plasticity models. With the recent advances in spherical nanoindentation data analysis, there is now an unprecedented opportunity to obtain insights into the change in local mechanical properties during deformation in materials at sub-micron length scales. In this work, we quantify the evolution of microstructure and local mechanical properties in tantalum under dynamic loading conditions (split Hopkinson pressure bar), to capture the structure- property correlations at the sub-micron length scale. Relevant information is obtained by combining local mechanical property information captured using spherical nanoindentation with complimentary structure information at the indentation site measured using EBSD. The aim is to gain insight into the role of these microstructural features during macroscopic deformation, particularly their influence on the development of mechanical heterogeneities that lead to failure.

Introduction: Early child development occurs within an interactive environment, initially dominated by parents or caregivers, and is heavily influenced by the dynamics of this social context. The current study probed the neurobiology of "family personality", or family functioning, in the context of parent-child dyadic interaction using a two-person neuroimaging modality., Methods: One hundred and five parent-child dyads (child mean age 5 years 4 months) were recruited. Functional near-infrared spectroscopy (fNIRS) hyperscanning was employed to measure neural synchrony while dyads completed a mildly stressful interactive task. Family functioning was measured through the Family Adaptability and Cohesion Scale IV (FACES-IV)., Results: Synchrony during stress was significantly greater than synchrony during both baseline and recovery conditions for all dyads. A significant interaction between neural synchrony in each task condition and familial balanced flexibility was found, such that higher levels of balanced flexibility were associated with greater changes in frontal cortex neural synchrony as dyads progressed through the three task conditions., Discussion: Parent-child dyads from families who display heightened levels of balanced flexibility are also more flexible in their engagement of neural synchrony when shifting between social conditions. This is one of the first studies to utilize a two-person imaging modality to explore the links between family functioning and interbrain synchrony between parents and their children., (© 2024 Wiley Periodicals LLC.)

Intranasal administration of drugs serves as a promising, noninvasive option for the treatment of various disorders of the central nervous system and upper respiratory tract. Predictive, ie, realistic and accurate, particle tracking in the human nasal cavities is an essential step to achieve these goals. The major factors affecting aerosol transport and deposition are the inhalation flowrate, the particle characteristics, and the nasal airway geometry. In vivo and in vitro studies using nasal cavity casts provide realistic images regarding particle-deposition pattern. Computational Fluid-Particle Dynamics (CF-PD) studies can offer a flexible, detailed and cost effective solution to the problem of direct drug delivery. The open-source software OpenFOAM was employed to conduct, after model validation, laminar and turbulent fluid-particle dynamics simulations for representative nasal cavities. Specifically, micron particles and nanoparticles were both individually tracked for different steady airflow rates to determine sectional deposition efficiencies. For micron particles, inertial forces were found to be the dominating factor, resulting in higher deposition for larger particles, mainly due to impaction. In contrast, diffusional effects are more important for nanoparticles. With a focus on the olfactory region, the detailed analysis of sectional deposition concentrations, considering a wide range of particle diameters, provide new physical insight to the particle dynamics inside human nasal cavities. The laminar/turbulent Euler-Lagrange modelling approach for simulating the fate of nanoparticles form a foundation for future studies focusing on targeted drug delivery. A major application would be direct nanodrug delivery to the olfactory region to achieve large local concentrations for possible migration across the blood-brain-barrier., (Copyright © 2020. Published by Elsevier Ltd.)

Large, freestanding membranes with remarkably high elastic modulus (>10 GPa) have been fabricated through the self-assembly of ligand-stabilized inorganic nanocrystals, even though these nanocrystals are connected only by soft organic ligands (e.g., dodecanethiol or DNA) that are not cross-linked or entangled. Recent developments in the synthesis of polymer-grafted nanocrystals have greatly expanded the library of accessible superlattice architectures, which allows superlattice mechanical behavior to be linked to specific structural features. Here, colloidal self-assembly is used to organize polystyrene-grafted Au nanocrystals at a fluid interface to form ordered solids with sub-10-nm periodic features. Thin-film buckling and nanoindentation are used to evaluate the mechanical behavior of polymer-grafted nanocrystal superlattices while exploring the role of polymer structural conformation, nanocrystal packing, and superlattice dimensions. Superlattices containing 3-20 vol % Au are found to have an elastic modulus of ∼6-19 GPa, and hardness of ∼120-170 MPa. We find that rapidly self-assembled superlattices have the highest elastic modulus, despite containing significant structural defects. Polymer extension, interdigitation, and grafting density are determined to be critical parameters that govern superlattice elastic and plastic deformation.

Introduction: Patients with progressive, metastatic, RAI-refractory differentiated thyroid cancer (DTC), as well as patients with advanced medullary (MTC) and anaplastic thyroid cancer represent a cohort for which therapeutic options are limited. The recent discoveries in the molecular mechanisms implicated in TC have provided insight of the pathogenesis and progression of disease. In that respect, targeted therapies have emerged as a promising alternative for the treatment of those patients. Areas covered: Tyrosine Kinase Inhibitors (TKIs) have been studied extensively in TC: sorafenib and lenvatinib have been approved by the FDA for the treatment of metastatic, RAI-refractory DTC, while vandetanib and cabozantinib are FDA approved for use in advanced MTC. Moreover, several additional TKIs, multi-targeted or specific, are currently under investigation in TC. The current manuscript provides an extensive review of the literature regarding targeted therapies in TC including the rationale behind their use, the clinical trials and an expert opinion on their use. Literature in English appearing at PubMed was thoroughly reviewed, especially manuscripts of the last 5 years. Expert commentary: Patients with advanced, progressive, metastatic TC should be evaluated for enrollment in a clinical trial or should be placed on treatment with one of the FDA- and EMA- approved agents.

Purpose: Surgical site infections (SSIs) are associated with patient morbidity and increased health care costs. Although several national organizations including the University HealthSystem Consortium (UHC), the National Surgical Quality Improvement Program (NSQIP), and the National Healthcare Safety Network (NHSN) monitor SSI, there is no standard reporting methodology., Methods: We queried the UHC, NSQIP, and NHSN databases from July 2012 to June 2014 for SSI after gynecologic surgery at our institution. Each organization uses different definitions and inclusion and exclusion criteria for SSI. The rate of SSI was also obtained from chart review from April 1 to June 30, 2014. SSI was classified as superficial, deep, or organ space infection. The rates reported by the agencies were compared with the rates obtained by chart review using Fisher's exact test., Results: Overall SSI rates for the databases were as follows: UHC, 1.5%; NSQIP, 8.8%; and NHSN, 2.8% (P < .001). The individual databases had wide variation in the rate of deep infection (UHC, 0.7%; NSQIP, 4.7%; NHSN, 1.3%; P < .001) and organ space infection (UHC, 0.4%; NSQIP, 4.4%; NHSN, 1.4%; P < .001). In agreement with the variation in reporting methodology, only 19 cases (24.4%) were included in more than one database and only one case was included in all three databases (1.3%)., Conclusion: There is discordance among national reporting agencies tracking SSI. Adopting standardized metrics across agencies could improve consistency and accuracy in assessing SSI rates.

Objective: To evaluate whether the use of intraoperative dexmedetomidine (DEX) during lung cancer surgery may reduce the incidence of acute kidney injury (AKI)., Design: A retrospective study., Setting: An academic hospital., Participants: Data were collected from 1,207 adult patients who underwent resection for non-small-cell lung cancer between January 2004 and December 2012., Interventions: None., Measurements and Main Results: All patients had a general balanced anesthetic technique, and dexmedetomidine use was at the discretion of the anesthesiologist. Data analysis was done utilizing the Wilcoxon rank sum tests and Chi-square tests to compare continuous variables and categoric variables between the 2 groups, respectively. Multivariate logistic analysis with backward selection was fitted to find out factors for AKI incidence. Overall, 8.1% of the patients developed AKI during their hospital stay. There were no statistically significant differences in demographic, perioperative variables, and the incidence of AKI between patients who did and did not receive DEX. A logistic regression model was fitted to determine factors independently associated with AKI. Factors that were independently associated with AKI included body mass index, American Society of Anesthesiologists 3-4, hypertension, smoking status, and thoracotomy procedure., Discussion: The authors hypothesized that DEX use would be associated with a decreased incidence of AKI in thoracic surgery; however, they were unable to prove this hypothesis. Their results did demonstrate that there are 5 factors independently associated with AKI., (Copyright © 2016 Elsevier Inc. All rights reserved.)

A 52-year-old man underwent tracheal resection during regional anesthesia with sedation. The patient had a prior history of tracheostomy resulting in tracheal stenosis and expiratory wheezing. Awake tracheal resection with spontaneous ventilation was performed. Patient cooperation was essential to identify the lesion and perform the resection safely., (Published by Elsevier Inc.)

A 29-year-old man with no medical history presented with a left scalp abscess and left temporal oedema. He was initially started on treatment for community acquired Methicillin-resistant Staphylococcus aureus with sulfamethoxazole and trimethoprim. Over the next 2 weeks, his swelling improved; however, he continued to have localised swelling and drainage from the area. Eventually, larvae of a botfly were removed from his scalp, and his symptoms resolved., (2014 BMJ Publishing Group Ltd.)

Background: Fingernail onychomycosis is a fungal infection of the finger nails. It is mainly produced by yeasts, dermatophytes and molds and sometimes it shows a mixed infection. It is a cosmetic issue rather than a medical problem., Aims: This study was conducted with the aim of exposing the fungal concept in nail diseases, to introduce nail testing which was underutilized as a diagnostic tool despite being involved in many dermatological conditions, as well as to introduce microbiological techniques in the diagnosis of nail diseases, based on the clinical parameters only., Materials and Methods: A total of 45 samples were tested in our laboratory by using 20% KOH and culture plates of Sabouraud's Dextrose Agar (SDA) which were mixed with chloramphenicol and cycloheximide., Results: A total of 37.78% samples were identified as positive by culture, among which 17.78% were KOH positive and 20.00% were KOH negative. 62.22% were culture negative. The predominant pathogen was yeast (64.71%), followed by dermatophytes (17.65%). A mixed infection was identified in 11.76%. Scytalidium hyalinum was identified in 5.88% of the cases. Fungi commonly presented in the middle age, between 31-40 years of age, due to trauma at the work site and in women, due to their wet work., Conclusion: This study highlighted the yeast, genus Candida as the main pathogen which caused fingernail onychomycosis in our region. So, it is imperative to diagnose it properly by using microbiological techniques and to treat it properly.