Quantitative sampling by IR-MALDESI is not susceptible to tissue heterogeneity in a multi-organ model.

Quantitative mass spectrometry imaging (qMSI) provides the relative or absolute analyte quantities in a biological specimen in a spatially resolved manner. However, the chemical complexity and physical structure of biological specimens often require one to precisely account for matrix effects in qMSI platforms. Infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI) completely ablates a volume of cryosectioned tissue.

Oversampling for Enhanced Spatial Resolution of Zebrafish by Top-Hat IR-MALDESI-MSI.

Mass spectrometry imaging (MSI) has become a significant tool for measuring chemical species in biological tissues, where much of the impact of these platforms lies in their capability to report the spatial distribution of analytes for correlation to sample morphology. As a result, enhancement of spatial resolution has become a frontier of innovation in the field, and necessary developments are dependent on the ionization source. More particularly, laser-based imaging sources may require modifications to the optical train or alternative sampling techniques.

Experimental Open Air Burning of Vegetation Enhances Organic Matter Chemical Heterogeneity Compared to Laboratory Burns.

Wildfires produce solid residuals that have unique chemical and physical properties compared to unburned materials, which influence their cycling and fate in the natural environment. Visual burn severity assessment is used to evaluate post-fire alterations to the landscape in field-based studies, yet muffle furnace methods are commonly used in laboratory studies to assess molecular scale alterations along a temperature continuum. Here, we examined solid and leachable organic matter characteristics from chars visually characterized as low burn severity that were created either on an open air burn table or from low-temperature muffle furnace burns.

Geometry, mechanics and actuation of intrinsically curved folds.

We combine theory and experiments to explore the kinematics and actuation of intrinsically curved folds (ICFs) in otherwise developable shells. Unlike origami folds, ICFs are not bending isometries of flat sheets, but arise non-isometric processes (growth/moulding) or by joining sheets along curved boundaries. Experimentally, we implement both, first making joined ICFs from paper, then fabricating flat liquid crystal elastomer (LCE) sheets that morph into ICFs upon heating/swelling programmed metric changes.

Evaluating Accuracy in Five Commercial Sleep-Tracking Devices Compared to Research-Grade Actigraphy and Polysomnography.

The development of consumer sleep-tracking technologies has outpaced the scientific evaluation of their accuracy. In this study, five consumer sleep-tracking devices, research-grade actigraphy, and polysomnography were used simultaneously to monitor the overnight sleep of fifty-three young adults in the lab for one night. Biases and limits of agreement were assessed to determine how sleep stage estimates for each device and research-grade actigraphy differed from polysomnography-derived measures.

Surface Instability in a Nematic Elastomer.

Liquid crystal elastomers (LCEs) are soft phase-changing solids that exhibit large reversible contractions upon heating, Goldstone-like soft modes, and resultant microstructural instabilities. We heat a planar LCE slab to isotropic, clamp the lower surface, then cool back to nematic. Clamping prevents macroscopic elongation, producing compression and microstructure.

Synthesis and Additive Manufacturing of Hydrazone-Linked Covalent Organic Framework Aerogels.

Covalent Organic Frameworks (COFs) are crystalline, porous organic materials. Recent studies have demonstrated novel processing strategies for COFs to form adaptable architectures, but these have focused primarily on imine-linked COFs. This work presents a new synthesis and processing route to produce crystalline hydrazone-linked COF gels and aerogels with hierarchical porosity.

Enabling Solution Processable COFs through Suppression of Precipitation during Solvothermal Synthesis.

Covalent organic frameworks (COFs) are crystalline, nanoporous materials of interest for various applications, but current COF synthetic routes lead to insoluble aggregates which precludes processing for practical implementation. Here, we report a COF synthesis method that produces a stable, homogeneous suspension of crystalline COF nanoparticles that enables the preparation of COF monoliths, membranes, and films using conventional solution-processing techniques. Our approach involves the use of a polar solvent, diacid catalyst, and slow reagent mixing procedure at elevated temperatures which altogether enable access to crystalline COF nanoparticle suspension that does not aggregate or precipitate when kept at elevated temperatures.

Effect of Implant Size, Version and Rotator Cuff Tendon Preservation on the Outcome of Reverse Shoulder Arthroplasty.

Introduction: Functional outcomes following reverse geometry shoulder arthroplasty can vary. This study assessed the effects of glenosphere size, humeral stem version, posterior rotator cuff status and subscapularis repair on patient-reported outcome and range of motion.  Methods: A consecutive series of 132 patients from two orthopaedic centres that use the same onlay system for reverse shoulder arthroplasty were reviewed over a six-year period.

Understanding the effect of liquid crystal content on the phase behavior and mechanical properties of liquid crystal elastomers.

Liquid crystal elastomers are stimuli-responsive, shape-shifting materials. They typically require high temperatures for actuation which prohibits their use in many applications, such as biomedical devices. In this work, we demonstrate a simple and general approach to tune the order-to-disorder transition temperature () or nematic-to-isotropic transition temperature () of LCEs through variation of the overall liquid crystal mass content.

Range of Movement and Patient-Reported Outcomes in Shoulder Arthroplasty in the Elderly: A Comparison of Anatomical Versus Reverse Shoulder Replacements.

Introduction Shoulder arthroplasty is in increasing demand in the elderly given the rising prevalence of glenohumeral osteoarthritis (OA) across the population. There is a dearth of evidence in the current literature comparing anatomical total shoulder arthroplasty and reverse total shoulder arthroplasty (RTSA) in the elderly population. This study compares patient-reported outcome measures and range of movement (ROM) between anatomical and reverse total shoulder replacements in matched patient cohorts over the age of 70 years.

Depth dependence of climatic controls on soil microbial community activity and composition.

Subsoil microbiomes play important roles in soil carbon and nutrient cycling, yet our understanding of the controls on subsoil microbial communities is limited. Here, we investigated the direct (mean annual temperature and precipitation) and indirect (soil chemistry) effects of climate on microbiome composition and extracellular enzyme activity throughout the soil profile across two elevation-bioclimatic gradients in central California, USA. We found that microbiome composition changes and activity decreases with depth.

Corrosion Resistance of Sulfur-Selenium Alloy Coatings.

Despite decades of research, metallic corrosion remains a long-standing challenge in many engineering applications. Specifically, designing a material that can resist corrosion both in abiotic as well as biotic environments remains elusive. Here a lightweight sulfur-selenium (S-Se) alloy is designed with high stiffness and ductility that can serve as an excellent corrosion-resistant coating with protection efficiency of ≈99.

Bursal Acromial Reconstruction (BAR) Using an Acellular Dermal Allograft for Massive, Irreparable Posterosuperior Rotator Cuff Tears: A Dynamic Biomechanical Investigation.

Purpose: To investigate the effect of bursal acromial reconstruction (BAR) using an acellular dermal allograft on glenohumeral joint kinematics including maximum abduction angle, glenohumeral superior translation, cumulative deltoid force, and subacromial contact pressure.

Methods: In this dynamic biomechanical cadaveric shoulder study, 8 fresh-frozen cadaveric shoulders (age 53.4 ± 14.

Bursal Acromial Reconstruction (BAR) Using an Acellular Dermal Allograft as a Surgical Solution for the Treatment of Massive Irreparable Rotator Cuff Tears.

Massive, irreparable rotator cuff tears in patients without severe signs of osteoarthritis remains a major challenge for orthopaedic surgeons. These can be a source of significant pain and functional loss occurring most commonly in a relatively frail, elderly patient population. A plethora of surgical techniques covering minimally invasive, arthroscopic techniques and open, salvage procedures have been described for this challenging patient cohort.

Endophyte-Promoted Phosphorus Solubilization in .

Phosphorus is one of the essential nutrients for plant growth, but it may be relatively unavailable to plants because of its chemistry. In soil, the majority of phosphorus is present in the form of a phosphate, usually as metal complexes making it bound to minerals or organic matter. Therefore, inorganic phosphate solubilization is an important process of plant growth promotion by plant associated bacteria and fungi.

Clinical Outcome of Transtendon Repair of Partial Articular Supraspinatus Tendon Avulsion Tear.

Partial articular supraspinatus tendon avulsion (PASTA) tears are common. However, there is no consensus on the optimal surgical technique for the management of grade 3 tears (>50%). The authors report a retrospective consecutive case series of 64 patients with grade 3 PASTA lesions.

Reactive 3D Printing of Shape-Programmable Liquid Crystal Elastomer Actuators.

3D printed, stimuli-responsive materials that reversibly actuate between programmed shapes are promising for applications ranging from biomedical implants to soft robotics. However, current 3D printing of reversible actuators significantly limits the range of possible shapes and/or shape responses because they couple the print path to mathematically determined director profiles to elicit a desired shape change. Here, we report a reactive 3D-printing method that decouples printing and shape-programming steps, enabling a broad range of complex architectures and virtually any arbitrary shape changes.

Arthroscopic Superior Capsular Reconstruction of the Shoulder Using Dermal Allograft.

Irreparable massive cuff tears in young patients pose a difficult problem for shoulder surgeons. Arthroscopic superior capsular reconstruction has shown promise in recent years in the treatment of this challenging patient population. The majority of the literature is limited to surgical techniques.

Phosphorus Speciation in Atmospherically Deposited Particulate Matter and Implications for Terrestrial Ecosystem Productivity.

Chemical forms of phosphorus (P) in airborne particulate matter (PM) are poorly known and do not correlate with solubility or extraction measurements commonly used to infer speciation. We used P X-ray absorption near-edge structure (XANES) and P nuclear magnetic resonance (NMR) spectroscopies to determine P species in PM collected at four mountain sites (Colorado and California). Organic P species dominated samples from high elevations, with organic P estimated at 65-100% of total P in bulk samples by XANES and 79-88% in extracted fractions (62-84% of total P) by NMR regardless of particle size (≥10 or 1-10 μm).

Histological incorporation of acellular dermal matrix in the failed superior capsule reconstruction of the shoulder.

Background: Superior capsule reconstruction addresses massive rotator cuff tears using allografts and aims to restore the natural superior constraint of the shoulder and therefore shoulder biomechanics and function. There is no evidence relating to the histological incorporation of these grafts.

Methods: 27 superior capsule reconstructions were performed between June 2016 and November 2017.

3D Printing of Metformin HCl PVA Tablets by Fused Deposition Modeling: Drug Loading, Tablet Design, and Dissolution Studies.

The main aim of this work was to 3D print metformin HCl-loaded PVA (ML-PVA) tablets by fused deposition modeling. A modified solvent diffusion approach was used to improve drug loading. PVA filaments were placed in metformin HCl solution in ethanol containing low water content (10%(v/v)) to enhance the drug's solubility.