Constructions of diagonal quartic and sextic surfaces with infinitely many rational points

In this note we construct several infinite families of diagonal quartic surfaces \begin{equation*} ax^4+by^4+cz^4+dw^4=0, \end{equation*} where $a,b,c,d\in\Z\setminus\{0\}$ with infinitely many rational points and satisfying the condition $abcd\neq \square$. In particular, we present an infinite family of diagonal quartic surfaces defined over \Q with Picard number equal to one and possessing infinitely many rational points. Further, we present some sextic surfaces of type $ax^6+by^6+cz^6+dw^i=0$, $i=2$, $3$, or $6$, with infinitely many rational points.Comment: revised version will appear in International Journal of Number Theor

A review of advancements in synthesis, manufacturing and properties of environment friendly biobased Polyfurfuryl Alcohol Resin and its Composites

The quest for environmentally friendly and sustainable materials in the production of fibre reinforced composite materials has led to the use of biobased materials, which are easily accessible and renewable. Biomass-derived chemicals, their derivatives, and their applications have become increasingly prevalent in various industries and processes, greatly contributing to the goal of ecological sustainability. The biobased Polyfurfuryl Alcohol (PFA) resin is one of such polymeric materials that is gaining attention for composite applications due to its endearing Fire Smoke and Toxicity properties. Derived from agricultural by products such as sugar cane bagasse, it has been known for applications within the foundry, coating, and wood industries. However, there has been a growing interest in its use for fibre reinforced composite applications. For this reason, this work intends to provide a comprehensive review of the PFA resin in relationship to fibre reinforced composites applications. The work provides an in-depth discussion on the synthesis, curing process, manufacturing, and properties of the PFA resin as well as its composites

Safety evaluation of adenovirus type 4 and type 7 vaccine live, oral in military recruits

AbstractBefore the widespread adoption of vaccination, adenovirus type 4 and type 7 were long associated with respiratory illnesses among military recruits. When supplies were depleted and vaccination was suspended in 1999 for approximately a decade, respiratory illnesses due to adenovirus infections resurged. In March 2011, a new live, oral adenovirus vaccine was licensed by the US Food and Drug Administration and was first universally administered to military recruits in October 2011, leading to rapid, dramatic elimination of the disease within a few months. As part of licensure, a postmarketing study (Sentinel Surveillance Plan) was performed to detect potential safety signals within 42days after immunization of military recruits. This study retrospectively evaluated possible adverse events related to vaccination using data from the Armed Forces Health Surveillance Branch Defense Medical Surveillance System (DMSS) database. Among 100,000 recruits who received the adenovirus vaccine, no statistically significant greater risk of prespecified medical events was observed within 42days after vaccination when compared with a historical cohort of 100,000 unvaccinated recruits. In an initial statistical analysis of International Classification of Disease, 9th Revision, Clinical Modification codes, a statistically significant higher risk for 19 other (not prespecified) medical events occurring in 5 or more recruits was observed among vaccinated compared with unvaccinated groups. After case record data abstraction for attribution and validation, two events (psoriasis [21 vs 7 cases] and serum reactions [12 vs 4 cases]) occurred more frequently in the vaccinated cohort. A causal relation of these rare events with adenovirus vaccination could not be established given confounding factors in the DMSS, such as coadministration of other vaccines and incomplete or inaccurate medical information, for some recruits. Prospective surveillance assessing these uncommon, but potentially relevant, immune-related symptoms may be beneficial in defining potential causal association with adenovirus vaccination

Response to: "Renal biopsies should be performed whenever treatment strategies depend on renal involvement"

We thank Chemouny et al for their letter and concur with their conclusions. As we state (1): “A positive biopsy for AAV is helpful when considering an initial diagnosis or recurrent disease.” In our view, renal biopsy is important to establish diagnosis and may also provide an indication of prognostic trajectory and although existing classification systems need further validation, changes like glomerular sclerosis have obvious adverse prognostic value for patients with AAV (2-4). The Delphi process, for the scope of the current recommendations, identified the role of biopsy at both diagnosis and follow-up as an important item for update. Histopathological evidence of vasculitis, such as pauci-immune glomerulonephritis or necrotising vasculitis in any organ, remains the gold standard for diagnostic purposes. The likely diagnostic yield varies and is dependent on the organ targeted and in patients with GPA with renal involvement can be as high as 91.5% from renal biopsy (5). As Chemouny and colleagues have demonstrated, a renal biopsy was definitive in determining their management decisions. However during follow-up when relapses occur, it may be prudent to consider judicious use of further kidney biopsy during suspected renal relapse since the cause for acute kidney injury may be due to another cause other than AAV (6). Kind regards, M Yates, C Mukhtyar and DR Jayne on behalf of co-authors

Regional Integration of Equity Markets in Sub-Saharan Africa

Equity markets in developing and emerging economies have grown in number and importance as a result of financial market globalisation. However, their role in economic growth and development is enhanced if nascent markets are integrated with well-established ones. Market integration, measured by the transmission of returns volatility, is identified across a sample of SSA countries, using a unique dataset. Evidence for potential integration between financial markets in Sub-Saharan Africa (SSA) is found. Spillovers are found across markets, some unidirectional and others bi-directional. However, continued illiquidity and incomplete institutions indicate that an integrated financial community remains premature, and considerable regulatory reform and harmonisation will be necessary for this to succeed

Utilization of deep learning to quantify fluid volume of neovascular age-related macular degeneration patients based on swept-source OCT imaging: The ONTARIO study.

PURPOSE: To evaluate the predictive ability of a deep learning-based algorithm to determine long-term best-corrected distance visual acuity (BCVA) outcomes in neovascular age-related macular degeneration (nARMD) patients using baseline swept-source optical coherence tomography (SS-OCT) and OCT-angiography (OCT-A) data. METHODS: In this phase IV, retrospective, proof of concept, single center study, SS-OCT data from 17 previously treated nARMD eyes was used to assess retinal layer thicknesses, as well as quantify intraretinal fluid (IRF), subretinal fluid (SRF), and serous pigment epithelium detachments (PEDs) using a novel deep learning-based, macular fluid segmentation algorithm. Baseline OCT and OCT-A morphological features and fluid measurements were correlated using the Pearson correlation coefficient (PCC) to changes in BCVA from baseline to week 52. RESULTS: Total retinal fluid (IRF, SRF and PED) volume at baseline had the strongest correlation to improvement in BCVA at month 12 (PCC = 0.652, p = 0.005). Fluid was subsequently sub-categorized into IRF, SRF and PED, with PED volume having the next highest correlation (PCC = 0.648, p = 0.005) to BCVA improvement. Average total retinal thickness in isolation demonstrated poor correlation (PCC = 0.334, p = 0.189). When two features, mean choroidal neovascular membranes (CNVM) size and total fluid volume, were combined and correlated with visual outcomes, the highest correlation increased to PCC = 0.695 (p = 0.002). CONCLUSIONS: In isolation, total fluid volume most closely correlates with change in BCVA values between baseline and week 52. In combination with complimentary information from OCT-A, an improvement in the linear correlation score was observed. Average total retinal thickness provided a lower correlation, and thus provides a lower predictive outcome than alternative metrics assessed. Clinically, a machine-learning approach to analyzing fluid metrics in combination with lesion size may provide an advantage in personalizing therapy and predicting BCVA outcomes at week 52

Maturational patterns of left ventricular rotational mechanics in pre-term infants through 1 year of age

BACKGROUND: Pre-mature birth impacts left ventricular development, predisposing this population to long-term cardiovascular risk. The aims of this study were to investigate maturational changes in rotational properties from the neonatal period through 1 year of age and to discern the impact of cardiopulmonary complications of pre-maturity on these measures. METHODS: Pre-term infants (\u3c29 weeks at birth, n = 117) were prospectively enrolled and followed to 1-year corrected age. Left ventricular basal and apical rotation, twist, and torsion were measured by two-dimensional speckle-tracking echocardiography and analysed at 32 and 36 weeks post-menstrual age and 1-year corrected age. A mixed random effects model with repeated measures analysis was used to compare rotational mechanics over time. Torsion was compared in infants with and without complications of cardiopulmonary diseases of pre-maturity, specifically bronchopulmonary dysplasia, pulmonary hypertension, and patent ductus arteriosus. RESULTS: Torsion decreased from 32 weeks post-menstrual age to 1-year corrected age in all pre-term infants (p \u3c 0.001). The decline from 32 to 36 weeks post-menstrual age was more pronounced in infants with cardiopulmonary complications, but was similar to healthy pre-term infants from 36 weeks post-menstrual age to 1-year corrected age. The decline was due to directional and magnitude changes in apical rotation over time (p \u3c 0.05). CONCLUSION: This study tracks maturational patterns of rotational mechanics in pre-term infants and reveals torsion declines from the neonatal period through 1 year. Cardiopulmonary diseases of pre-maturity may negatively impact rotational mechanics during the neonatal period, but the myocardium recovers by 1-year corrected age

Markers of Maternal and Infant Metabolism are Associated with Ventricular Dysfunction in Infants of Obese Women with Type 2 Diabetes

BACKGROUND To test the hypothesis that infants born to obese women with pregestational type 2 diabetes mellitus (IBDM) have ventricular dysfunction at one month that is associated with markers of maternal lipid and glucose metabolism. METHODS In a prospective observational study of IBDM (OB+DM, n=25), echocardiography measures of septal, left (LV) and right ventricular (RV) function and structure were compared at one month of age to infants born to OB mothers without DM (OB, n=24), and non-OB without DM (Lean, n=23). Basal maternal lipid and glucose kinetics and maternal plasma and infant (cord) plasma were collected for hormone and cytokine analyses. RESULTS RV, LV, and septal strain measures were lower in the OB+DM infants vs. other groups, without evidence of septal hypertrophy. Maternal hepatic insulin sensitivity, maternal plasma free fatty acid concentration, and cord plasma insulin and leptin most strongly predicted decreased septal strain in the OB+DM infants. CONCLUSION IBDM’s have reduced septal function at one month in the absence of septal hypertrophy, which is associated with altered maternal and infant lipid and glucose metabolism. These findings suggest that maternal obesity and DM may have a prolonged impact on the cardiovascular health of their offspring, despite resolution of cardiac hypertrophy

Pulmonary Artery Acceleration Time Provides a Reliable Estimate of Invasive Pulmonary Hemodynamics in Children

Background Pulmonary artery acceleration time (PAAT) is a non-invasive method to assess pulmonary hemodynamics, but lacks validity in children. This study sought to evaluate the accuracy of Doppler echocardiography (DE) derived PAAT in predicting right heart catheterization (RHC) derived pulmonary arterial pressure (PAP), pulmonary vascular resistance (PVR) and compliance in children. Methods Prospectively acquired and retrospectively measured DE derived PAAT and RHC derived systolic PAP (sPAP), mean PAP (mPAP), index PVR (PVRi) and compliance were compared by regression analysis in a derivation cohort of 75 children (median age, 5.3 years; 1.3–12.6) with wide ranges of pulmonary hemodynamics. To account for heart rate variability, PAAT was adjusted for right ventricle ejection time (RVET) and corrected by the RR interval. Regression equations incorporating PAAT and PAAT:RVET from the derivation cohort were then evaluated for the accuracy of its predictive values for invasive pulmonary hemodynamics in a validation cohort of 50 age- and weight- matched children with elevated PAP and PVR. Results There were significant inverse correlations between PAAT and RHC derived mPAP (r = −0.82) and PVRi (r= −0.78) and direct correlation (r= 0.78) between PAAT and pulmonary compliance in the derivation cohort. For detection of pulmonary hypertension (PRVi > 3 WU x m2 and mPAP > 25 mmHg), PAAT < 90 msec and PAAT:RVET < 0.31 resulted in a sensitivity of 97% and a specificity of 95%. In the derivation cohort, the regression equations relating PAAT with mPAP and PVRi were: mPAP = 48 – 0.28 x PAAT and PVRi = 9 –0.07 x PAAT. These PAAT integrated equations predicted RHC measured pulmonary hemodynamics in the validation cohort with good correlations (r = 0.88, 0.83 respectively), small biases (<10%), and minimal coefficient of variation (<8%). Conclusions PAAT inversely correlates with RHC measured pulmonary hemodynamics and directly correlates with pulmonary arterial compliance in children. The study established PAAT based regression equations in children to accurately predict RHC derived PAP and PVR

Bounds for Lepton Flavor Violation and the Pseudoscalar Higgs in the General Two Higgs Doublet Model using g−2g-2 muon factor

Current experimental data from the $g-2$ muon factor, seems to show the necessity of physics beyond the Standard Model (SM), since the difference between SM and experimental predictions is 2.6$\sigma$. In the framework of the General Two Higgs Doublet Model (2HDM), we calculate the muon anomalous magnetic moment to get lower and upper bounds for the Flavour Changing (FC) Yukawa couplings in the leptonic sector. We also obtain lower bounds for the mass of the pseudoscalar Higgs ($m_{A^0}$) as a function of the parameters of the model.Comment: 12 pages, RevTex4, 5 figures. Improved presentation, updated experimental data, amplified analysis, new figures added. Subbmited to Phys. Rev.