Multidimensional, High Precision Measurements of Beam Single Spin Asymmetries in Semi-inclusive π^{+} Electroproduction off Protons in the Valence Region

High precision measurements of the polarized electron beam-spin asymmetry in semi-inclusive deep inelastic scattering (SIDIS) from the proton have been performed using a 10.6 GeV incident electron beam and the CLAS12 spectrometer at Jefferson Lab. We report here a high precision multidimensional study of single π^{+} SIDIS data over a large kinematic range in Bjorken x, fractional energy, and transverse momentum of the hadron as well as photon virtualities Q^{2} ranging from 1-7  GeV^{2}. In particular, the structure function ratio F_{LU}^{sinϕ}/F_{UU} has been determined, where F_{LU}^{sinϕ} is a twist-3 quantity that can reveal novel aspects of emergent hadron mass and quark-gluon correlations within the nucleon. The data's impact on the evolving understanding of the underlying reaction mechanisms and their kinematic variation is explored using theoretical models for the different contributing transverse momentum dependent parton distribution functions.

Totally Implantable Oxygen Generator (TIOG) for Hypoxia and Hypoxemia

Hypoxia and hypoxemia are the conditions when oxygen is depleted from the cell due to, for example, respiratory failure, cancer, etc. While the current therapy brought reasonable clinical outcomes, its systematic nature of oxygen delivery can be compromised by a significant dropout and side effects. This paper presents a totally implantable oxygen generator (TIOG) for localized, highly controllable, real-time, and targeted oxygen delivery.

METHODS

The TIOG system, an ultra-low power implantable wireless platform, is built using off-the-shelf components. The TIOG can be remotely operated to enable a tailored oxygen delivery based on electrolysis with a precisely controlled electrical signal (i.e., current level, frequency, and duty cycle).

RESULTS

The in vitro experiments demonstrate that the TIOG could deliver oxygen with a rate of 9.27 ± 1.9 µmol/L/min with the pulsed electrical current (800 µA, 600 µs pulse or 6% duty cycle with 10 ms period). The system could also suppress chlorine generation under the safety guideline (5 mg/L). Operating at 433 MHz ISM band, the TIOG could be wirelessly controlled from up to 600 cm distance with a 0%-bit error rate (BER) and 0%-packet error rate (PER). A single charge of the battery could operate the system for up to 3.3 hr, which can be wirelessly recharged for long-term operation.

CONCLUSION

The longevity of the TIOG system enables ambulatory oxygen therapy in a much longer-term than current practice.

Improved Λp Elastic Scattering Cross Sections between 0.9 and 2.0 GeV/c as a Main Ingredient of the Neutron Star Equation of State

Strange matter is believed to exist in the cores of neutron stars based on simple kinematics. If this is true, then hyperon-nucleon interactions will play a significant part in the neutron star equation of state. Yet, compared to other elastic scattering processes, there is very little data on Λ-N scattering. This experiment utilized the CEBAF Large Acceptance Spectrometer (CLAS) detector to study the Λp→Λp elastic scattering cross section in the incident Λ momentum range 0.9-2.0  GeV/c. These are the first data on this reaction since the 1970s. The new cross sections have significantly better accuracy and precision than the existing world data, and the techniques developed here can also be used in future experiments.

First Measurement of Timelike Compton Scattering

We present the first measurement of the timelike Compton scattering process, γp→p^{'}γ^{*}(γ^{*}→e^{+}e^{-}), obtained with the CLAS12 detector at Jefferson Lab. The photon beam polarization and the decay lepton angular asymmetries are reported in the range of timelike photon virtualities 2.25<Q^{'2}<9  GeV^{2}, squared momentum transferred 0.1<-t<0.8  GeV^{2}, and average total center-of-mass energy squared s=14.5  GeV^{2}. The photon beam polarization asymmetry, similar to the beam-spin asymmetry in deep virtual Compton scattering, is sensitive to the imaginary part of the Compton form factors and provides a way to test the universality of the generalized parton distributions. The angular asymmetry of the decay leptons accesses the real part of the Compton form factors and thus the D-term in the parametrization of the generalized parton distributions.

Effect of HIV infection on pre- and post-liver transplant mortality in patients with organ failure

OBJECTIVES

Organ failure (OF), a leading cause of death in HIV-positive individuals, is common in patients undergoing liver transplantation (LT). We examined the impact of HIV infection on pre- and post-LT mortalities in cirrhotic patients stratified by the number and type of OFs.

METHODS

We performed a cross-sectional study and a retrospective cohort study using the US National Inpatient Sample (NIS) and the United Network for Organ Sharing (UNOS) registry data, respectively. Patients who had not yet undergone LT from the NIS database (2010-2014) and patients undergoing LT from the UNOS database (2003-2016) were included in the study.

RESULTS

Analysis of patients (201 348) from the NIS database showed that one [adjusted odds ratio (aOR) 1.531; 95% confidence interval (CI) 1.160-2.023], two (aOR 1.624; 95% CI 1.266-2.083) or three or more OFs (aOR 1.349; 95% CI 1.165-1.562) were associated with higher pre-LT mortality in HIV-infected patients compared with HIV-negative patients with the corresponding number of OFs. In patients without OF, HIV infection was not associated with increased pre-LT mortality. UNOS data for patients undergoing LT (38 942) showed that the presence of two or more OFs was associated with increased post-LT 1-year mortality in HIV-infected patients compared with non-HIV-infected patients with the corresponding number of OFs (aOR 2.342; 95% CI 1.576-3.480). However, in patients with no OF or only one OF, HIV infection was not associated with increased post-LT 1-year mortality (aOR 1.372; 95% CI 0.911-2.068).

CONCLUSIONS

The results of this study emphasize the importance of preventing OF development, and justify LT for HIV-infected patients with no or only one OF.

Observation of Beam Spin Asymmetries in the Process ep→e^{'}π^{+}π^{-}X with CLAS12

The observation of beam spin asymmetries in two-pion production in semi-inclusive deep inelastic scattering off an unpolarized proton target is reported. The data presented here were taken in the fall of 2018 with the CLAS12 spectrometer using a 10.6 GeV longitudinally spin-polarized electron beam delivered by CEBAF at JLab. The measured asymmetries provide the first opportunity to extract the parton distribution function e(x), which provides information about the interaction between gluons and quarks, in a collinear framework that offers cleaner access than previous measurements. The asymmetries also constitute the first ever signal sensitive to the helicity-dependent two-pion fragmentation function G_{1}^{⊥}. A clear sign change is observed around the ρ mass that appears in model calculations and is indicative of the dependence of the produced pions on the helicity of the fragmenting quark.

Remote Monitoring of Heart Transplant Recipients during the COVID-19 Pandemic

Purpose

The COVID-19 pandemic created significant challenges in monitoring heart transplant (HT) recipients for rejection due to efforts to minimize contact with the hospital setting. The aim of this study was to evaluate the safety and efficacy of transitioning HT patients to home phlebotomy and a monitoring protocol based on gene expression profiling (GEP) and donor derived cell free DNA (ddcfDNA).

Methods

A single-center cohort study that prospectively enrolled consecutive HT patients who were transitioned to a remote monitoring protocol employing home phlebotomy and non-invasive surveillance for rejection. Patients were enrolled starting at 2 months post-HT. Positive GEP values were defined as ≥32 (up to 6 months post-HT) and ≥34 (> 6 months post-HT). A positive ddcfDNA score was defined as >0.12%. A positive biopsy was defined as grade ≥1B/1R

Results

246 HT patients were enrolled and followed for a minimum of 3 months. Mean age was 56±14, 71.5% were male, and median time from transplant was 2.7 years. The average distance of patients from the hospital was 25.6 miles. 359 blood tests were drawn for detection of GEP and ddcfDNA and 102 biopsies performed (Figure). Among 32 patients who had negative results on both tests and had a biopsy, 0 had a positive biopsy. Of 25 patients who had positive results on both tests and had a biopsy, 3 (12%) had a positive biopsy. The biopsy positivity rate in patients who were GEP+/ddcfDNA- was 6% and in patients who were GEP-/ddcfDNA+ was 8%. None of the positive biopsies were associated with hemodynamic compromise. 15 (6%) of patients were admitted due to allograft rejection during the study period. There were no deaths.

Conclusion

Using a remote monitoring protocol with home phlebotomy and noninvasive rejection surveillance was feasible and safe in HT recipients. In this cohort, the combination of negative GEP and ddcfDNA scores was accurate at predicting a lack of allograft rejection.

A24 FCGBP MAINTAINS MUC2 MUCUS STRUCTURAL INTEGRITY BY STABILIZING THE MUCUS LAYER IN RESPONSE TO THE COLONIC PATHOGEN, ENTAMOEBA HISTOLYTICA

Background

MUC2 mucin is the major component of the colonic mucus bilayer that serves as the first line of innate host defense against pathogens while supporting a healthy microbiota and regulating epithelial barrier function. Proteomic studies of colonic mucus have identified various mucus-associated proteins. One of the most abundant is FCGBP, similar to MUC2 mucin, but its interaction with MUC2 or function is not known. Here, we elucidated FCGBP functional role in stabilizing MUC2 mucus and in innate host defence against Entamoeba histolytica (Eh).

Aims

Hypothesis: MUC2 mucin and FCGBP are coordinately produced and play an important role in innate host defense. The specific aims are:

1. To determine if FCGBP alters the structural integrity of the mucus layer

2. To determine the role of FCGBP in Eh infection

Methods

FCGBP mRNA and protein expression induced by Eh, in WT and FCGBP CRISPR/Cas9 LS174T goblet cells were analysed by RT-PCR and Western blotting. To compare integrity of the mucus layer, fluorescent Eh and 1μM fluorescent beads were inoculated on WT and KO monolayers and adherent Eh and bead penetrability analyzed. To quantify MUC2 and FCGBP degradation by Eh, purified MUC2 and recombinant FCGBP were incubated with Eh proteases (SPs) and Western blotted using highly specific antibodies against various regions of the proteins.

Results

In response to live Eh, FCGBP and MUC2 mRNA and protein expressions were significantly increased in a time-dependent manner. Surprisingly, FCGBP KO cells elicited robust expression of pro-inflammatory cytokine mRNA and protein as compared to WT cells. More fluorescent Eh were attached to the mucus layer of FCGBP KO cells as compared to WT or MUC2 KO cells. Fluorescent beads penetrated further towards the epithelial cell surface in KO as compared to WT cells. Interestingly, while both MUC2 and FCGBP from purified polymeric mucins were degraded by Eh SPs, FCGBP cleavage occurred at a faster rate than MUC2. Degradation of FCGBP and MUC2 was mediated by EhCP-A5 cysteine proteinase using purified MUC2 and recombinant FCGBP.

Conclusions

In WT goblet cells, FCGBP and MUC2 were upregulated temporally in response to Eh. The increase in pro-inflammatory cytokine expression in FCGBP KO cells in response to Eh suggests that Eh directly interacted with the cell surface suggesting an impaired protective mucus layer. In support of this, fluorescent beads penetrated the mucus layer close to the cell surface and more Eh were attached to FCGBP KO mucus demonstrating that FCGBP was critical in providing structural integrity of the mucus layer. In response to Eh, FCGBP degradation was a prerequisite for MUC2 cleavage, providing direct evidence that FCGBP and MUC2 interactions conferred biophysical properties of the protective functions of the mucus gel.

Funding Agencies

CIHR

Photoproduction of the f_{2}(1270) Meson Using the CLAS Detector

The quark structure of the f_{2}(1270) meson has, for many years, been assumed to be a pure quark-antiquark (qq[over ¯]) resonance with quantum numbers J^{PC}=2^{++}. Recently, it was proposed that the f_{2}(1270) is a molecular state made from the attractive interaction of two ρ mesons. Such a state would be expected to decay strongly to final states with charged pions due to the dominant decay ρ→π^{+}π^{-}, whereas decay to two neutral pions would likely be suppressed. Here, we measure for the first time the reaction γp→π^{0}π^{0}p, using the CEBAF Large Acceptance Spectrometer detector at Jefferson Lab for incident beam energies between 3.6 and 5.4 GeV. Differential cross sections, dσ/dt, for f_{2}(1270) photoproduction are extracted with good precision due to low backgrounds and are compared to theoretical calculations.

Thickness measurement of nm HfO2 films

A pilot study for the thickness measurement of HfO2 films was performed by the Surface Analysis Working Group (SAWG) of the Consultative Committee for Amount of Substance (CCQM). The aim of this pilot study was to ensure the equivalency in the measurement capability of national metrology institutes for the thickness measurement of HfO2 films. In this pilot study, the thicknesses of six HfO2 films with nominal thickness from 1 nm to 4 nm were measured by X-ray Photoelectron Spectroscopy (XPS), X-ray Reflectometry(XRR), X-ray Fluorescence Analysis (XRF), Transmission Electron Spectroscopy (TEM), Spectroscopic Ellipsometry (SE) and Rutherford Backscattering Spectrometry (RBS). The reference thicknesses were determined by mutual calibration of a zero-offset method (Medium Energy Ion Scattering Spectroscopy (MEIS) of KRISS) and a method traceable to the length unit (the average thicknesses of three XRR data except the thinnest film). These reference thicknesses are traceable to the length unit because they are based on the traceability of XRR. For the thickness measurement by XPS, the effective attenuation length of Hf 4f electrons was determined. In the cases of XRR and TEM, the offset values were determined from a linear fitting between the reference thicknesses and the individual data by XRR and TEM. The amount of substance of HfO2, expressed as thickness of HfO2 films (in both linear and areal density units), was found to be a good subject for a CCQM key comparison.

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The final report has been peer-reviewed and approved for publication by the CCQM.

Associations of serum monocyte-to-high-density lipoprotein cholesterol ratio with digital ulcers and skin fibrosis in patients with systemic sclerosis

Objective: To investigate the relationship between the monocyte-to-high-density lipoprotein cholesterol ratio (MHR) and clinical manifestations in patients with systemic sclerosis (SSc).Method: This was a cross-sectional analysis of a cohort study comprising 111 female SSc patients recruited from a tertiary care rheumatology centre. We also assessed 222 age-matched female healthy controls. Serum MHR was measured in all study participants. Digital ulcer (DU) was defined as an active or healed ulceration, and the magnitude of skin fibrosis was determined according to the modified Rodnan skin score (mRSS).Results: The mean age and median disease duration in patients with SSc were 56.3 years and 98 months, respectively. The MHR in SSc patients was significantly higher than that in controls. DU was found in 35 patients (31.5%) with SSc (active in 12 and healed in 23), and the median mRSS was 8. SSc patients with DU had a significantly higher median MHR than those without (11.43 vs 7.62, p < 0.001), and MHR significantly positively correlated with mRSS (ρ = 0.289, p = 0.002). Multivariable logistic regression revealed that an elevated MHR was independently associated with increased risk of DU (odds ratio = 1.21; 95% confidence interval = 1.07-1.35; p = 0.002). In the multivariable linear regression analysis, higher MHR showed a significant association with increased log-transformed mRSS (unstandardized β = 0.052, p = 0.003).Conclusion: Our findings suggest that the MHR could be serve as a potential biomarker of the risk of DU and advanced skin fibrosis in patients with SSc.

The brain and behavioral correlates of motor-related analgesia (MRA)

The human motor system has the capacity to act as an internal form of analgesia. Since the discovery of the potential influence of motor systems on analgesia in rodent models, clinical applications of targeting the motor system for analgesia have been implemented. However, a neurobiological basis for motor activation's effects on analgesia is not well defined. Motor-related analgesia (MRA) is a phenomenon wherein a decrease in pain symptoms can be achieved through either indirect or direct activation of the motor axis. To date, research has focused on (a) evaluating the pain-motor interaction as one focused on the acute protection from painful stimuli; (b) motor cortex stimulation for chronic pain; or (c) exercise as a method of improving chronic pain in animal and human models. This review evaluates (1) current knowledge surrounding how pain interferes with canonical neurological performance throughout the motor axis; and (2) the physiological basis for motor-related analgesia as a means to reduce pain symptom loads for patients. A proposal for future research directions is provided.

Extraction of Beam-Spin Asymmetries from the Hard Exclusive π^{+} Channel off Protons in a Wide Range of Kinematics

We have measured beam-spin asymmetries to extract the sinϕ moment A_{LU}^{sinϕ} from the hard exclusive e[over →]p→e^{'}nπ^{+} reaction above the resonance region, for the first time with nearly full coverage from forward to backward angles in the center of mass. The A_{LU}^{sinϕ} moment has been measured up to 6.6  GeV^{2} in -t, covering the kinematic regimes of generalized parton distributions (GPD) and baryon-to-meson transition distribution amplitudes (TDA) at the same time. The experimental results in very forward kinematics demonstrate the sensitivity to chiral-odd and chiral-even GPDs. In very backward kinematics where the TDA framework is applicable, we found A_{LU}^{sinϕ} to be negative, while a sign change was observed near 90° in the center of mass. The unique results presented in this Letter will provide critical constraints to establish reaction mechanisms that can help to further develop the GPD and TDA frameworks.

Using search engine data to gauge public interest in mental health, politics and violence in the context of mass shootings

Despite significant potential for providing insight to private perceptions and behaviors, search engine data has yet to be utilized as a means of gauging the U.S. public’s interest and understanding of mental health in the context of gun violence and politics. An analysis of Google Trends revealed that Mental health searches increased in volume starting in the beginning of the current decade. Notably, both “mental health” and “gun(s)” were searched with greater frequency the week after the mass shooting events occurred. Related searches after the event also observed a significant increase in interest in mental health and gun regulation, legal reform, mass shootings, and gun(s). Results suggest that the American public’s perception of mental illness increasingly incorporates associations with themes of violence and politics, which becomes more apparent surrounding mass shooting events. Future studies are needed to determine implications for stigmatization of vulnerable groups, and possible relations to media coverage.

A Prospective Cohort Study of Bisphenol A Exposure from Dental Treatment

Laboratory studies show that bisphenol A (BPA) leaches from bisphenol A-glycidyl methacrylate (bisGMA)-based dental materials. We aimed to quantify the extent to which children are exposed to BPA from dental treatment with bisGMA materials, by amount of treatment and type of sedation. We hypothesized that posttreatment urinary BPA (uBPA) concentrations would be higher among patients with more surfaces treated with bisGMA-based materials and among patients receiving general anesthesia compared with pretreatment concentrations. We conducted a prospective cohort study in 211 children, 4 to 12 y old, who had no prior resin-based dental treatment. We measured uBPA concentrations twice before treatment and at 2 d and 1, 4, and 16 wk posttreatment. We abstracted treatment data (surfaces treated) from the chart. We generated descriptive statistics and compared pre- and posttreatment uBPA concentrations using generalized estimating equations. Participants were 51% female, 46% non-White, and 74% publicly insured. The median age was 6 y. The mean number of tooth surfaces exposed to BisGMA materials (composites/sealants) was 7.5 (SD 5.3). Overall, uBPA concentrations were 86% higher (95% confidence interval [CI] 42% to 143%, P < 0.001) at 2 d posttreatment compared with pretreatment concentrations. The uBPA concentrations 2 d posttreatment versus pretreatment tended to be higher (112%, 95% CI 53% to 194%) among those receiving treatment on >4 surfaces than those receiving treatment on ≤4 surfaces (50%, 95% CI -2% to 130%). Two days after treatment, uBPA was significantly higher than pretreatment concentrations in children receiving nitrous oxide but not in those receiving general anesthesia. Among all findings, uBPA concentrations returned to baseline by 4 wk. Children experience short-term increases in BPA from dental treatment. The impact of relatively high, short-term BPA exposure on child health is unknown. Given the widespread use of BisGMA-based dental materials and that chronic low-dose BPA exposure may adversely affect child health, strategies that minimize BPA exposure could potentially improve child health.

A Machine Learning Enabled Wireless Intracranial Brain Deformation Sensing System

A leading cause of traumatic brain injury (TBI) is intracranial brain deformation due to mechanical impact. This deformation is viscoelastic and differs from a traditional rigid transformation. In this paper, we describe a machine learning enabled wireless sensing system that predicts the trajectory of intracranial brain deformation. The sensing system consists of an implantable soft magnet and an external magnetic sensor array with a sensing volume of 12 × 12 × 4 mm³. Machine learning algorithm predicts the brain deformation by interpreting the magnetic sensor outputs created by the change in position of the implanted soft magnet. Three different machine learning models were trained on calibration data: (1) random forests, (2) k-nearest neighbors, and (3) a multi-layer perceptron-based neural network. These models were validated using both in vitro (a needle inserted into PVC gel) and in vivo (blast exposure to live and dead rat brains) experiments. The in vitro gel deformation predicted by these machine learning models showed excellent agreement with the camera measurements and had absolute error = 138 μm, Fréchet distance = 372 μm with normalized Procrustes disparity = 0.034. The in vivo brain deformation predicted by these models had absolute error = 50 μm, Fréchet distance = 95 μm with normalized Procrustes disparity = 0.055 for dead animal and absolute error = 125 μm, Fréchet distance = 289 μm with normalized Procrustes disparity = 0.2 for live animal respectively. These results suggest that the proposed machine learning enabled sensor system can be an effective tool for measuring in situ brain deformation.