Comparison of the "Tall and Fall" Versus "Drop and Drive" Pitching Styles: Analysis of Major League Baseball Pitchers During a Single Season.

Background: Previous research has documented the proportion of "tall and fall" (TF) and "drop and drive" (DD) pitching styles among Major League Baseball (MLB) pitchers who underwent ulnar collateral ligament reconstruction (UCLR). The proportion of these 2 styles among all MLB pitchers remains unknown.

Purpose: To determine the proportion of the TF and DD pitching styles in all rostered MLB pitchers during a single season as well as the proportion of TF and DD pitchers who sustained an upper extremity (UE) injury and those who underwent UCLR.

Retrospective Analysis of Ulnar Collateral Ligament Reconstructions in Major League Baseball Pitchers: A Comparison of the "Tall and Fall" Versus "Drop and Drive" Pitching Styles.

Background: Previous pilot research has investigated differences in elbow valgus torque between the "tall and fall" (TF) and "drop and drive" (DD) pitching styles. Whether one of these pitching styles is associated with a greater rate of ulnar collateral ligament reconstruction (UCLR) is currently unknown.

Purpose: To determine the proportion of Major League Baseball (MLB) pitchers using the TF and DD pitching styles who underwent UCLR over a 10-year period.

A NIST facility for resonant soft x-ray scattering measuring nano-scale soft matter structure at NSLS-II.

We present the design and performance of a polarized resonant soft x-ray scattering (RSoXS) station for soft matter characterization built by the national institute of standards and technology at the national synchrotron light source-II (NSLS-II). The RSoXS station is located within the spectroscopy soft and tender beamline suite at NSLS-II located in Brookhaven national laboratory, New York. Numerous elements of the RSoXS station were designed for optimal performance for measurements on soft matter systems, where it is of critical importance to minimize beam damage and maximize collection efficiency of polarized x-rays.

Lymphatic Vessel on a Chip with Capability for Exposure to Cyclic Fluidic Flow.

The lymphatic system is a complex organ system that is essential in regulating the development of host immune responses. Because of the complexity of the lymphatic system and the existence of few models that replicate human lymphatic vessels, there is a need for a primary cell-based lymphatic model that can provide a better understanding of the effects of flow parameters, therapeutics, and other stimuli on lymphatic vessel behavior. In this report, a fluidic device models the cyclical lymphatic flow under normal and disease conditions.

Electron and X-ray Focused Beam-Induced Cross-Linking in Liquids: Toward Rapid Continuous 3D Nanoprinting and Interfacing using Soft Materials.

Multiphoton polymer cross-linking evolves as the core process behind high-resolution additive microfabrication with soft materials for implantable/wearable electronics, tissue engineering, microrobotics, biosensing, drug delivery, Electrons and soft X-rays, in principle, can offer even higher resolution and printing rates. However, these powerful lithographic tools are difficult to apply to vacuum incompatible liquid precursor solutions used in continuous additive fabrication. In this work, using biocompatible hydrogel as a model soft material, we demonstrate high-resolution in-liquid polymer cross-linking using scanning electron and X-ray microscopes.

Revisiting the Photon-Drag Effect in Metal Films.

The photon-drag effect, the rectified current in a medium induced by conservation of momentum of absorbed or redirected light, is a unique probe of the detailed mechanisms underlying radiation pressure. We revisit this effect in gold, a canonical Drude metal. We discover that the signal for p-polarized illumination in ambient air is affected in both sign and magnitude by adsorbed molecules, opening previous measurements for reinterpretation.

Pumpless microfluidic devices for generating healthy and diseased endothelia.

We have developed a pumpless cell culture chip that can recirculate small amounts of cell culture medium (400 μL) in a unidirectional flow pattern. When operated with the accompanying custom rotating platform, the device produces an average wall shear stress of up to 0.588 Pa ± 0.

Nondegenerate Parametric Resonance in Large Ensembles of Coupled Micromechanical Cantilevers with Varying Natural Frequencies.

We investigate the collective dynamics and nondegenerate parametric resonance (NPR) of coplanar, interdigitated arrays of microcantilevers distinguished by their cantilevers having linearly expanding lengths and thus varying natural frequencies. Within a certain excitation frequency range, the resonators begin oscillating via NPR across the entire array consisting of 200 single-crystal silicon cantilevers. Tunable coupling generated from fringing electrostatic fields provides a mechanism to vary the scope of the NPR.

Absolute Deflection Measurements in a Micro- and Nano-Electromechanical Fabry-Perot Interferometry System.

Fabry-Perot laser interferometry is a common laboratory technique used to interrogate resonant micro- and nano-electromechanical systems (MEMS/NEMS). This method uses the substrate beneath a vibrating MEMS/NEMS device as a static reference mirror, encoding relative device motion in the reflected laser power. In this work, we present a general approach for calibrating these optical systems based on measurements of large-amplitude motion that exceeds one half of the laser wavelength.

Nanophotonic Atomic Force Microscope Transducers Enable Chemical Composition and Thermal Conductivity Measurements at the Nanoscale.

The atomic force microscope (AFM) offers a rich observation window on the nanoscale, yet many dynamic phenomena are too fast and too weak for direct AFM detection. Integrated cavity-optomechanics is revolutionizing micromechanical sensing; however, it has not yet impacted AFM. Here, we make a groundbreaking advance by fabricating picogram-scale probes integrated with photonic resonators to realize functional AFM detection that achieve high temporal resolution (<10 ns) and picometer vertical displacement uncertainty simultaneously.

High-Resolution Imaging and Spectroscopy at High Pressure: A Novel Liquid Cell for the Transmission Electron Microscope.

We demonstrate quantitative core-loss electron energy-loss spectroscopy of iron oxide nanoparticles and imaging resolution of Ag nanoparticles in liquid down to 0.24 nm, in both transmission and scanning transmission modes, in a novel, monolithic liquid cell developed for the transmission electron microscope (TEM). At typical SiN membrane thicknesses of 50 nm the liquid-layer thickness has a maximum change of only 30 nm for the entire TEM viewing area of 200×200 µm.

Metal-dielectric-metal resonators with deep subwavelength dielectric layers increase the near-field SEIRA enhancement.

Plasmonic nanostructures presenting either structural asymmetry or metal-dielectric-metal (M-D-M) architecture are commonly used structures to increase the quality factor and the near-field confinement in plasmonic materials. This characteristic can be leveraged for example to increase the sensitivity of IR spectroscopy, via the surface enhanced IR absorption (SEIRA) effect. In this work, we combine structural asymmetry with the M-D-M architecture to realize Ag-Ag(2)O-Ag asymmetric ring resonators where two Ag layers sandwich a native silver oxide (Ag(2)O) layer.

Absorption spectroscopy and imaging from the visible through mid-infrared with 20 nm resolution.

Absorption spectroscopy and mapping from visible through mid-IR wavelengths has been achieved with spatial resolution exceeding the limit imposed by diffraction via the photothermal induced resonance technique. Correlated vibrational (chemical), and electronic properties are obtained simultaneously with topography with a wavelength-independent resolution of ≈20 nm using a single laboratory-scale instrument. This marks the highest resolution reported for PTIR, as determined by comparing height and PTIR images, and its first extension to near-IR and visible wavelengths.

Near-field asymmetries in plasmonic resonators.

Surface-enhanced infrared absorption (SEIRA) spectroscopy exploits the locally enhanced field surrounding plasmonic metamaterials to increase the sensitivity of infrared spectroscopy. The light polarization and incidence angle are important factors for exciting plasmonic nanostructures; however, such angle dependence is often ignored in SEIRA experiments, typically carried out with Cassegrain objectives. Here, the photothermal induced resonance technique and numerical simulations are used to map the distribution and intensity of SEIRA hot-spots surrounding gold asymmetric split ring resonators (ASRRs) as a function of light polarization and incidence angle.

Assessing chemical heterogeneity at the nanoscale in mixed-ligand metal-organic frameworks with the PTIR technique.

Recently, the use of mixtures of organic-building-block linkers has given chemists an additional degree of freedom for engineering metal-organic frameworks (MOFs) with specific properties; however, the poor characterization of the chemical complexity of such MixMOF structures by conventional techniques hinders the verification of rational design. Herein, we describe the application of a technique known as photothermal induced resonance to individual MixMOF microcrystals to elucidate their chemical composition with nanoscale resolution. Results show that MixMOFs isoreticular to In-MIL-68, obtained either directly from solution or by postsynthetic linker exchange, are homogeneous down to approximately 100 nm.

Nanoscale imaging of plasmonic hot spots and dark modes with the photothermal-induced resonance technique.

The collective oscillation of conduction electrons, responsible for the localized surface plasmon resonances, enables engineering nanomaterials by tuning their optical response from the visible to terahertz as a function of nanostructure size, shape, and environment. While theoretical calculations helped tremendously in understanding plasmonic nanomaterials and optimizing their light matter interaction, only a few experimental techniques are available to study these materials with high spatial resolution. In this work, the photothermal-induced resonance (PTIR) technique is applied for the first time to image the dark plasmonic resonance of gold asymmetric split ring resonators (A-SRRs) in the mid-infrared (IR) spectral region with nanoscale resolution.

Chemical imaging beyond the diffraction limit: experimental validation of the PTIR technique.

Photothermal induced resonance (PTIR) has recently attracted great interest for enabling chemical identification and imaging with nanoscale resolution. In this work, electron beam nanopatterned polymer samples are fabricated directly on 3D zinc selenide prisms and used to experimentally evaluate the PTIR lateral resolution, sensitivity and linearity. It is shown that PTIR lateral resolution for chemical imaging is comparable to the lateral resolution obtained in the atomic force microscopy height images, up to the smallest feature measured (100 nm).

Val66Met in brain-derived neurotrophic factor affects stimulus-induced plasticity in the human pharyngeal motor cortex.

Background & Aims: Polymorphisms in brain-derived neurotrophic factor (BDNF) can affect brain and behavioral responses. However, little is known about the effects of a single nucleotide polymorphism (SNP) in BDNF, at codon 66 (the Val-Met substitution, detected in approximately 33% of the Caucasian population) on stimulation-induced plasticity in the cortico-bulbar system. We examined whether this SNP influenced outcomes of different forms of neurostimulation applied to the pharyngeal motor cortex.

X-ray modulation transfer functions of photostimulable phosphor image plates and scanners.

The modulation transfer functions of two types of photostimulable phosphor image plates were determined in the 10 keV to 50 keV x-ray energy range using a resolution test pattern with up to 10 line pairs per mm (LP/mm) and a wavelength dispersive x-ray spectrometer. Techniques were developed for correcting for the partial transmittance of the high energy x rays through the lead bars of the resolution test pattern, and the modulation transfer function (MTF) was determined from the measured change in contrast with LP/mm values. The MTF was convolved with the slit function of the image plate scanner, and the resulting point spread functions (PSFs) were in good agreement with the observed shapes and widths of x-ray spectral lines and with the PSF derived from edge spread functions.

High-resolution imaging spectrometer for recording absolutely calibrated far ultraviolet spectra from laser-produced plasmas.

An imaging spectrometer was designed and fabricated for recording far ultraviolet spectra from laser-produced plasmas with wavelengths as short as 155 nm. The spectrometer implements a Cassegrain telescope and two gratings in a tandem Wadsworth optical configuration that provides diffraction limited resolution. Spectral images were recorded from plasmas produced by the irradiation of various target materials by intense KrF laser radiation with 248 nm wavelength.

Development of backlighting sources for a Compton radiography diagnostic of inertial confinement fusion targets (invited).

We present scaled demonstrations of backlighter sources, emitting bremsstrahlung x rays with photon energies above 75 keV, that we will use to record x-ray Compton radiographic snapshots of cold dense DT fuel in inertial confinement fusion implosions at the National Ignition Facility (NIF). In experiments performed at the Titan laser facility at Lawrence Livermore National Laboratory, we measured the source size and the bremsstrahlung spectrum as a function of laser intensity and pulse length from solid targets irradiated at 2x10(17)-5x10(18) W/cm(2) using 2-40 ps pulses. Using Au planar foils we achieved source sizes down to 5.

Enhanced x-ray resolving power achieved behind the focal circles of Cauchois spectrometers.

Maintaining high resolving power is a primary challenge in hard x-ray spectroscopy of newly developed bright and transient x-ray sources such as laser-produced plasmas. To address this challenge, the line widths in x-ray spectra with energies in the 17 keV to 70 keV range were recorded by positioning the detectors on and behind the focal circles of Cauchois type transmission-crystal spectrometers. To analyze and understand the observed line widths, we developed a geometrical model that accounts for source broadening and various instrumental broadening mechanisms.

Response of a SiC photodiode to extreme ultraviolet through visible radiation.

The responsivity of a type 6H-SiC photodiode in the 1.5-400 nm wavelength range was measured using synchrotron radiation. The responsivity was 0.

X-ray absolute calibration of the time response of a silicon photodiode.

The time-dependent response of a 1-mm2 silicon photodiode was characterized by use of pulsed synchrotron radiation in the 4- to 16-nm-wavelength range. Modeling the input radiation pulse and the electrical response of the photodiode allowed the photodiode's capacitance as a function of wavelength and applied bias voltage to be determined. The capacitance was in the 7- to 19-pF range and resulted in response fall times as small as 0.