A variety of scattering-based, microscopy-based, and mobility-based methods are frequently used to probe the size distributions of colloidal nanoparticles with transmission electron microscopy (TEM) often considered to be the \"gold standard\". Charge detection mass spectrometry (CDMS) is an alternative method for nanoparticle characterization that can rapidly measure the mass and charge of individual nanoparticle ions with high accuracy. Two low polydispersity, ∼100 nm diameter nanoparticle size standards with different compositions (polymethyl methacrylate/polystyrene copolymer and 100% polystyrene) were characterized using both TEM and CDMS to explore the merits and complementary aspects of both methods. Mass and diameter distributions are rapidly obtained from CDMS measurements of thousands of individual ions of known spherical shape, requiring less time than TEM sample preparation and image analysis. TEM image-to-image variations resulted in a ∼1-2 nm range in the determined mean diameters whereas the CDMS mass precision of ∼1% in these experiments leads to a diameter uncertainty of just 0.3 nm. For the 100% polystyrene nanoparticles with known density, the CDMS and TEM particle diameter distributions were in excellent agreement. For the copolymer nanoparticles with unknown density, the diameter from TEM measurements combined with the mass from CDMS measurements enabled an accurate measurement of nanoparticle density. Differing extents of charging for the two nanoparticle standards measured by CDMS show that charging is sensitive to nanoparticle surface properties. A mixture of the two samples was separated based on their different extents of charging despite having overlapping mass distributions centered at 341.5 and 331.0 MDa.

OBJECTIVE: Within the past decade, Medicare Part B reimbursements for various surgical procedures have been declining, whereas health care expenses continue to increase. As a result, hospitals may increase service charges to offset losses in revenue, which may disproportionately affect underinsured patients. Our analysis aimed to characterize Medicare billing and utilization trends across common vascular surgical procedures.
METHODS: The 2017 to 2021 Medicare Physician and Other Practitioners by Provider and Service dataset was queried for Current Procedural Terminology (CPT) codes for common vascular surgery procedures. The average charges, reimbursements, charge-to-reimbursement ratios, and service counts were calculated for the most common interventions performed by vascular surgeons. Data was stratified by care setting, facility (inpatient and outpatient hospital) vs non-facility locations. All monetary values were adjusted to the 2021 United States dollars to account for inflation.
RESULTS: For facility settings, the mean charge billed to Medicare Part B increased from $3708 to $3952 (6.6%) from 2017 to 2021, with the average charge-to-reimbursement ratio increasing from 7.2 to 8.6. There were 17 of the 19 facility procedures that had a decline in reimbursements, decreasing from an average of $558 to $499 (-10.4%). Stab phlebectomy had the largest individual decrease in facility reimbursement (-53.5%), followed by above-knee amputation (-11.3%) and below-knee amputation (-11.0%). Both non-facility charges (-10.8%) and reimbursements (-12.2%) declined over the study period. Procedural utilization remained stable from 2017 to 2019. Tibial and femoral-popliteal atherectomy had increases of 45.9% and 33.7%, respectively, in overall procedural utilization when performed in non-facility settings from 2017 to 2019.
CONCLUSIONS: Our analysis of vascular surgery procedures billed to Medicare Part B from 2017 to 2021 demonstrates an increase in charges, a decline in reimbursements, and a resultant increase in charge-to-reimbursement ratios for facility care settings. In contrast, non-facility charges have decreased in the face of declining reimbursements. These markups in submitted charges in facility locations may serve as an additional barrier to accessing care for patients who are underinsured.

BACKGROUND: The present study aimed to test the hypothesis stating that the cognitive potential of individuals with deafblindness is equal to those without a deafblind condition, an assumption that until now has been empirically unsubstantiated within the field of deafblindness.
METHODS: To explore the assumption, 15 children and adolescents with CHARGE underwent cognitive assessment with WISC-V using a sequential two-level assessment design. The 1st level involved standardized test conditions. The 2nd level was designed as a continuation of the performances obtained from the 1st level and involved accommodations to compensate for sensory motor impairment. Statistical procedures involved the sample as a whole and when divided into two subgroups: (i) participants with CHARGE without deafblindness; (ii) participants with CHARGE and deafblindness using the 1st level scores as base line.
RESULTS: Although results showed significantly lower scores in the deafblind subgroup with standardized procedures, they approximated the others after accommodating for their sensory deficits. This positive increase proved significant.
CONCLUSIONS: Findings supported the assumption of equal cognitive potential of individuals with and without deafblindness. Results indicated that the children and adolescents with deafblindness had most effect of the accommodations, enabling them to approximate the results of the subgroup without deafblindness. These gains were attributed enhanced accessibility endorsed by the accommodations and represented the participants latent cognitive dispositions only realized under certain circumstances.

-Extremely-Low Frequencies (ELF, 30∼300Hz) transmitting antennas in wireless communications are often limited by antenna size and complex impedance matching networks. In this paper, we propose an ultra-small Artificial Electret Type Mechanical Antenna (AETMA), which is composed of a single charge electret and a driving structure, with high radiation efficiency and small size. In order to improve the electric dipole moment of the mechanical antenna, we employ a pin-plate corona polarization technique and a unidirectional stretching treatment to obtain a porous thin-film electret that can stably store a large amount of charge. Its surface charge density can reach 5.355 mC/m2 and we analyze its surface potential stability. To assess the radiation capability of AETMA, the radiation field models of three kinds of mechanical antennas are established and verified by simulation. Additionally, we simulate and compare the planar electret and curved electret configurations to determine the optimal form of AETMA. The radiation intensity of the planar electret is found to be superior under the same moment of inertia. Finally, a 1m-scale artificial electret antenna is designed based on the optimal model. Comparative analysis with existing rotary mechanical antenna schemes confirms the great potential of the proposed AETMA for portable, miniaturized and high-performance wireless communication devices.

Early identification of antibody candidates with drug-like properties is essential for simplifying the development of safe and effective antibody therapeutics. For subcutaneous administration, it is important to identify candidates with low self-association to enable their formulation at high concentration while maintaining low viscosity, opalescence, and aggregation. Here, we report an interpretable machine learning model for predicting antibody (IgG1) variants with low viscosity using only the sequences of their variable (Fv) regions. Our model was trained on antibody viscosity data (>100 mg/mL mAb concentration) obtained at a common formulation pH (pH 5.2), and it identifies three key Fv features of antibodies linked to viscosity, namely their isoelectric points, hydrophobic patch sizes, and numbers of negatively charged patches. Of the three features, most predicted antibodies at risk for high viscosity, including antibodies with diverse antibody germlines in our study (79 mAbs) as well as clinical-stage IgG1s (94 mAbs), are those with low Fv isoelectric points (Fv pIs < 6.3). Our model identifies viscous antibodies with relatively high accuracy not only in our training and test sets, but also for previously reported data. Importantly, we show that the interpretable nature of the model enables the design of mutations that significantly reduce antibody viscosity, which we confirmed experimentally. We expect that this approach can be readily integrated into the drug development process to reduce the need for experimental viscosity screening and improve the identification of antibody candidates with drug-like properties.

It is well known that protein corona affects the \"biological identity\" of nanoparticles (NPs), which has been seen as both a challenge and an opportunity. Approaches have moved from avoiding protein adsorption to trying to direct it, taking advantage of the formation of a protein corona to favorably modify the pharmacokinetic parameters of NPs. Although promising, the results obtained with engineered NPs still need to be completely understood. While much effort has been put into understanding how the surface of nanomaterials affects protein absorption, less is known about how proteins can affect corona formation due to their specific physicochemical properties. This review addresses this knowledge gap, examining key protein factors influencing corona formation, highlighting current challenges in studying protein-protein interactions, and discussing future perspectives in the field.

The Lorentz-Dirac equation is formulated and studied in flat Minkowski spacetime. A concise, novel derivation of the equation is presented. The problem is then enlarged to study radiation damping of an electron moving through a gravitational field. The equation of motion is obtained for this case as well. It is suggested the study of the problem might motivate experiments which could shed light on the recent work related to the emergence of space-time and its structure by means of quantum effects such as quantum entanglement.

Several simple secondary structures could form complex and diverse functional proteins, meaning that secondary structures may contain a lot of hidden information and are arranged according to certain principles, to carry enough information of functional specificity and diversity. However, these inner information and principles have not been understood systematically. In our study, we designed a structure-function alphabet of helix based on reduced amino acid clusters to describe the typical features of helices and delve into the information. Firstly, we selected 480 typical helices from membrane proteins, zymoproteins, transcription factors, and other proteins to define and calculate the interval range, and the helices are classified in terms of hydrophilicity, charge and length: (1) hydrophobic helix (≤43%), amphiphilic helix (43%∼71%), and hydrophilic helix (≥71%). (2) positive helix, negative helix, electrically neutral helix and uncharged helix. (3) short helix (≤8 aa), medium-length helix (9-28 aa), and long helix (≥29 aa). Then, we designed an alphabet containing 36 triplet codes according to the above classification, so that the main features of each helix can be represented by only three letters. This alphabet not only preliminarily defined the helix characteristics, but also greatly reduced the informational dimension of protein structure. Finally, we present an application example to demonstrate the value of the structure-function alphabet in protein functional determination and differentiation.

OBJECTIVE: Same day discharge (SDD) for colorectal surgery shows increasing promise in the era of enhanced recovery after surgery protocols and minimally invasive surgery. It has become increasingly relevant due to the constraints posed by the COVID-19 pandemic. The aim of this study was to compare SDD and postoperative day 1 (POD1) discharge to understand the clinical outcomes and financial impact on factors such as cost, charge, revenue, contribution margin and readmission.
METHODS: A retrospective review of colectomies was performed at a single institution over a 2-year period (n = 143). Two populations were identified: SDD (n = 51) and POD1 (n = 92). Patients were selected by International Statistical Classification of Diseases and Related Health Problems-10 (ICD-10) and Diagnosis Related Grouper (DRG) codes.
RESULTS: There was a statistically significant difference favouring SDD in total hospital cost (p < 0.0001), average direct costs (p < 0.0001) and average charges (p < 0.0016). SDD average hospital costs were $8699 (values in USD throughout) compared with $11 652 for POD 1 (p < 0.0001), and average SDD hospital charges were $85 506 compared with $97 008 for POD1 (p < 0.0016). The net revenue for SDD was $22 319 while for POD1 it was $26 173 (p = 0.14). Upon comparison of contribution margins (SDD $13 620 vs. POD1 $14 522), the difference was not statistically significant (p = 0.73). There were no identified statistically significant differences in operating room time, robotic console time, readmission rates or surgical complications.
CONCLUSIONS: Amidst the pandemic-related constraints, we found that SDD was associated with lower hospital costs and comparable contribution margins compared with POD1. Additionally, the study was unable to identify any significant difference between operating time, readmissions, and surgical complications when performing SDD.

Previous computational and experimental studies showed that charges located at the surroundings of hydrogen bonds can exert two opposite effects on them: rupture or strengthening of the hydrogen bond. This work aims to generalize the effect of charges in different hydrogen-bonded systems and to propose a coherent explanation of this effect. For these purposes, 19 systems with intra- and intermolecular hydrogen bonds were studied computationally with DFT. The FT-IR spectra of the systems were simulated, and two energy components of the hydrogen bond were studied separately to determine their variation upon the presence of a charge: charge transfer and molecular overlap. It was determined that either the breaking or strengthening of the hydrogen bond can be favored one over the other, for instance, depending on the heteroatom involved in the hydrogen bond. In addition, it is showed that the strengthening of the hydrogen bond by the presence of a charge is directly related to the decrease in charge transfer between the monomers, which is explained by an increase in molecular overlapping, suggesting a more covalent character of the interaction. The understanding of how hydrogen bonds are affected by charges is important, as it is a key towards a strategy to manipulate hydrogen bonds at convenience.