A Global Photometric Analysis of 2MASS Calibration Data

We present results from the application of a global photometric calibration (GPC) procedure to calibration data from the first 2 years of The Two Micron All Sky Survey (2MASS). The GPC algorithm uses photometry of both primary standards and moderately bright `tracer' stars in 35 2MASS calibration fields. During the first two years of the Survey, each standard was observed on approximately 50 nights, with about 900 individual measurements. Based on the photometry of primary standard stars and secondary tracer stars and under the assumption that the nightly zeropoint drift is linear, GPC ties together all calibration fields and all survey nights simultaneously, producing a globally optimized solution. Calibration solutions for the Northern and Southern hemisphere observatories are found separately, and are tested for global consistency based on common fields near the celestial equator. Several results from the GPC are presented, including establishing candidate secondary standards, monitoring of near-infrared atmospheric extinction coefficients, and verification of global validity of the standards. The solution gives long-term averages of the atmospheric extinction coefficients, A_J=0.096, A_H=0.026, A_{K_s}=0.066 (North) and A_J=0.092, A_H=0.031, A_{K_s}=0.065 (South), with formal error of 0.001. The residuals show small seasonal variations, most likely due to changing atmospheric content of water vapor. Extension of the GPC to approximately 100 field stars in each of the 35 calibration fields yields a catalog of more than two thousand photometric standards ranging from 10th to 14th magnitude, with photometry that is globally consistent to $\sim 1$.Comment: 19 pages, 10 figures; Submitted to AJ. The table of secondary standards is available from ftp://nova.astro.umass.edu/pub/nikolaev/ or ftp://anon-ftp.ipac.caltech.edu/pub/2mass/globalcal

Palatini Variational Principle for NN-Dimensional Dilaton Gravity

We consider a Palatini variation on a general $N$-Dimensional second order, torsion-free dilaton gravity action and determine the resulting equations of motion. Consistency is checked by considering the restraint imposed due to invariance of the matter action under simple coordinate transformations, and the special case of N=2 is examined. We also examine a sub-class of theories whereby a Palatini variation dynamically coincides with that of the "ordinary" Hilbert variational principle; in particular we examine a generalized Brans-Dicke theory and the associated role of conformal transformations.Comment: 16 pages, LaTe

Biodegradability of DBP precursors after drinking water ozonation

Ozonation is known to generate biodegradable organic matter, which is typically reduced by biological filtration to avoid bacterial regrowth in distribution systems. Post-chlorination generates halogenated disinfection byproducts (DBPs) but little is known about the biodegradability of their precursors. This study determined the effect of ozonation and biofiltration conditions, specifically ozone exposure and empty bed contact time (EBCT), on the control of DBP formation potentials in drinking water. Ozone exposure was varied through addition of H2O2 during ozonation at 1 mgO3/mgDOC followed by biological filtration using either activated carbon (BAC) or anthracite. Ozonation led to a 10% decrease in dissolved organic carbon (DOC), without further improvement from H2O2 addition. Raising H2O2 concentrations from 0 to 2 mmol/mmolO3 resulted in increased DBP formation potentials during post-chlorination of the ozonated water (target Cl2 residual after 24\ua0h\ua0=\ua01-2\ua0mg/L) as follows: 4 trihalomethanes (THM4, 37%), 8 haloacetic acids (HAA8, 44%), chloral hydrate (CH, 107%), 2 haloketones (HK2, 97%), 4 haloacetonitriles (HAN4, 33%), trichloroacetamide (TCAM, 43%), and adsorbable organic halogen (AOX, 27%), but a decrease in the concentrations of 2 trihalonitromethanes (THNM2, 43%). Coupling ozonation with biofiltration prior to chlorination effectively lowered the formation potentials of all DBPs including CH, HK2, and THNM2, all of which increased after ozonation. The dynamics of DBP formation potentials during BAC filtration at different EBCTs followed first-order reaction kinetics. Minimum steady-state concentrations were attained at an EBCT of about 10-20\ua0min, depending on the DBP species. The rate of reduction in DBP formation potentials varied among individual species before reaching their minimum concentrations. CH, HK2, and THNM2 had the highest rate constants of between 0.5 and 0.6 min(-1) followed by HAN4 (0.4 min(-1)), THM4 (0.3 min(-1)), HAA8 (0.2 min(-1)), and AOX (0.1 min(-1)). At an EBCT of 15\ua0min, the reduction in formation potential for most DBPs was less than 50% but was higher than 70% for CH, HK2, and THNM2. The formation of bromine-containing DBPs increased with increasing EBCT, most likely due to an increase in Br(-)/DOC ratio. Overall, this study demonstrated that the combination of ozonation and biofiltration is an effective approach to mitigate DBP formation during drinking water treatment

Meeting Report: Pharmaceuticals in Water—An Interdisciplinary Approach to a Public Health Challenge

BackgroundThe presence of pharmaceuticals in aquatic environments and in drinking water has prompted significant public interest regarding potential adverse ecological effects and risks to human health.ObjectivesThe Environmental Health Summit held in North Carolina, 10–11 November 2008, explored the issues associated with the presence and relative risk of trace levels of pharmaceuticals in water. More than 150 participants from government organizations and institutions, academia, industry, water utilities, and public interest groups participated in discussions aimed at evaluating the current knowledge on this issue and at identifying research gaps and innovative solution-oriented recommendations.DiscussionWe present different aspects related to the subject that were discussed at the summit, including the source, fate, and transport of pharmaceuticals, their exposure effects and potential risks to human and ecosystems, and the best management practices to address these issues. Recommendations placed emphasis on research needs as well as education, communication, prevention, and intervention programs, and other public health solutions and actions.ConclusionsDespite rising concerns about the presence of trace amounts of pharmaceuticals in drinking water, little evidence is currently available that associates these chemicals with adverse human health risks. In order to prioritize which pharmaceutical chemicals could potentially pose the highest risk to consumers and the environment, the summit participants concluded that more studies are needed to generate meaningful and accurate data

Effects of Attention-Deficit/Hyperactivity Disorder on Patients Undergoing Percutaneous Coronary Intervention Procedure: Insights from the National Inpatient Sample

Introduction: Attention Deficit Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder that can affect children and adults and is characterized by deficits in attention, self-regulation, and executive functioning. Symptoms can seriously affect daily functioning and may present as hyperactivity, inattentive behaviors, or a combination of both. There are data to suggest patients with ADHD suffer from increased rates of cardiovascular disease, however not much is known specifically regarding the relationship between ADHD and undergoing Percutaneous Coronary Intervention. We sought to examine this relationship in greater detail by perusing the national inpatient sample database to describe in-hospital trends and outcomes among these patients. Methods: Data were extracted from the National Inpatient Sample (NIS) Database for the years 2019 and 2020. The NIS was searched for hospitalizations of adult patients who underwent Percutaneous Coronary Intervention. Out of this Cohort, ADHD patients were identified. Multivariate logistic was used to adjust for confounders. Results: This study included 181,944 patients who underwent PCI procedure, of which 518 (0.3%) patients were diagnosed with ADHD. ADHD patients who underwent a PCI procedure had higher prevalence of hypertension (40.1%% Vs 35.7%% p Conclusion: In this nationally representative population‐based retrospective cohort study, ADHD was associated with worse outcomes including developing arrhythmia, acute kidney injury and congestive heart failure exacerbation among patients who underwent PCI. We did not find any statistical difference between the two groups when it came to mortality, length of stay and total hospital charges. This is most likely due to the small sample size of patients with ADHD undergoing PCI. More research is needed in this area

Infective Endocarditis Secondary to Needle Embolization to The Heart

Needle embolisms in the heart are very rare, even though the number of intravenous drug users (IVDUs) has increased over the past 10 years.Due to varied symptomology-chest pain, dyspnoea, fever, or asymptomatic, this remains a complex and likely underdiagnosed condition. We describe a 31-year-old female with past medical history of IV drug use who presented to the emergency room with heart palpitations and described it as her “heart feels funny” and shortness of breath. She acknowledged intravenous (IV) heroin use and stated that the last time to use IV drugs was 2 days before coming to the hospital. To our knowledge, this is the first case to describe a patient that comes in with chief complaint of heart palpitations and after that to be found to have a needle in her heart. Clinicians should be aware of these rare presentations to aid with proper treatment and management. Although further studies are warranted, we propose here that putting needle embolization in your differential diagnosis in patients with intravenous drug abuse who present with infective endocarditis

Effects of NSTEMI on Patients with Eating Disorders: Insights from the National Inpatient Sample

Introduction: Eating disorders (ED) such as bulimia and anorexia nervosa have detrimental implications on the health and wellbeing of children and young adults across the country. Cardiovascular implications are known to accompany these conditions, however there is a paucity of data looking specifically on the effects of NSTEMI on patients with these disorders. We sought to analyze this relationship further by examining these disorders within the national inpatient sample database to describe in-hospital trends and outcomes among those patients. Methods: Data were extracted from the National Inpatient Sample (NIS) Database for the years 2019 and 2020. The NIS was searched for hospitalizations of adult patients with eating disorder(s) with and without a concomitant diagnosis of NSTEMI using international classification of diseases-10th revision codes. Multivariate logistic was used to adjust for confounders. The primary outcome was inpatient mortality. Secondary outcomes were hospital length of stay (LOS), and total hospital charges (TOTHCG). SPSS software was used for statistical analysis. Results: This study included 16,889 patients who were diagnosed with eating disorders, of which only 56 (0.3%) patients were diagnosed with NSTEMI. ED patients with NSTEMI had higher prevalence of hypertension, diabetes mellitus and chronic kidney disease but not statistically different compared to patients with ED only. Multivariate regression showed that patients with both ED and NSTEMI had higher inpatient mortality compared to those with ED alone (OR 1.013, CI 1.011-1.015, p Conclusion: In this nationally representative population‐based retrospective cohort study, we concluded that ED patients hospitalized with NSTEMI have increased in-hospital mortality and worse outcomes. More research is needed in this area

Formation and Evaporation of a Naked Singularity in 2D Gravity

We describe a classical configuration of conformal matter forming a naked singularity and discuss its subsequent Hawking evaporation within the context of two dimensional dilaton gravity. The one loop analysis is credible for a large mass naked singularity and suggests the existence of a weak cosmological censorship that would cause it to explode into radiation upon forming. (Hardcopies of figures available on request)Comment: 10 pages, PHYZZX, preprint UATP-93/0

Mossbauer and optical spectroscopic study of temperature and redox effects on iron local environments in a Fe-doped (0.5 mol% Fe2O3)18Na2O–72SiO2 glass

Local environments of ferric and ferrous irons were systematically studied with Mössbauer (at liquid helium temperature)and ultraviolet–visible–near infrared spectroscopic methods for various 18Na2O–72SiO2 glasses doped with 0.5 mol% Fe2O3. These were prepared at temperatures of 1300–1600 °C in ambient air or at 1500 °C under reducing conditions with oxygen partial pressures from 12.3 to 0.27 x 10-7 atmospheres. The Mössbauer spectroscopic method identified three types of local environments, which were represented by the Fe3+ sextet, the Fe3+ doublet, and the Fe2+ doublet. The Fe3+ sextet ions were assigned to “isolated” octahedral ions. Under reducing conditions, the octahedral Fe3+ ions were readily converted into octahedral ferrous ions. The Fe3+ doublet exists both in octahedral and tetrahedral environment, mainly as tetrahedral sites in the reduced samples. The tetrahedral ions were found stable against reduction to ferrous ions. The Fe2+ doublet sites existed in octahedral coordination. Combining results from both spectroscopic studies, the 1120- and 2020-nm optical bands were assigned to octahedral ferrous ions with a different degree of distortion rather than different coordinations. Further, we assigned the 375-nm band to the transition of octahedral ferric ions that are sensitive to the change of oxygen partial pressure in glass melting and 415-, 435-, and 485-nm bands to the transitions of the tetrahedral ferric ions that are insensitive to oxidation states of the melt. The effect of ferric and ferrous ions with different coordination environments on the glass immiscibility was elucidated