Development of a laser heterodyne radiometer for regional methane leak detection.

We have developed and tested a laser heterodyne radiometer (LHR) for detecting methane leaks from upstream oil and gas infrastructure and landfills that uses the Sun as the signal light source, demonstrating here sensitivity sufficient to detect "super-emitter" leaks (>50kg/h, 1166 slm). Tracking optics follow the Sun during its apparent daily transit across the sky, and the system collects direct absorption data and optionally the 1f and 2f wavelength modulation spectroscopy (WMS) signals. The direct absorption data are processed in real time using a retrieval algorithm with a 5 s update rate to reveal the methane concentration versus altitude for each measurement line of sight. The 1f and 2f WMS signals are significantly non-intuitive because of the dramatic change in the methane lineshape as a function of pressure (altitude) but may ultimately provide useful information for leak localization. We describe herein modifications to the RF detection train and data collection system that allow faster and higher signal-to-noise ratio measurements. Preliminary results suggest that leaks giving rise to methane concentrations of the order of 500 ppm-m can be effectively detected-sensitivity similar to current satellites with more continuous temporal coverage and areal coverage of the order of 100s of km2 for relatively low cost. We outline a method of using an array of LHRs to localize the leak using lineshape information and tomographic reconstruction techniques that will be tested in future work.

Meeting the COVID-19 Deadlines: Choosing Assessments to Determine Eligibility.

Timely identification of children with disabilities is required by federal special education law (Individuals with Disabilities Education Improvement Act, 20 U.S.C. § 1400, 2004). During COVID-19, school psychologists have been faced with the challenge of completing valid, comprehensive, and diagnostic assessments when traditional methods are not an option. Traditional methods of testing have become nearly impossible due to social distancing requirements; therefore, alternate methods need to be considered. These alternate methods may be unfamiliar to the practitioner and/or lack validation to use with confidence. This study offers a prospective guide to help practitioners make safe and valid test selection and interpretation decisions during a pandemic. Examples of assessments analyzed using this guide are provided for the reader. In addition, a case study is provided as an example.

In-Orbit Performance of the GRACE Follow-on Laser Ranging Interferometer.

The Laser Ranging Interferometer (LRI) instrument on the Gravity Recovery and Climate Experiment (GRACE) Follow-On mission has provided the first laser interferometric range measurements between remote spacecraft, separated by approximately 220 km. Autonomous controls that lock the laser frequency to a cavity reference and establish the 5 degrees of freedom two-way laser link between remote spacecraft succeeded on the first attempt. Active beam pointing based on differential wave front sensing compensates spacecraft attitude fluctuations. The LRI has operated continuously without breaks in phase tracking for more than 50 days, and has shown biased range measurements similar to the primary ranging instrument based on microwaves, but with much less noise at a level of 1 nm/sqrt[Hz] at Fourier frequencies above 100 mHz.

Cobalt Boryl Complexes: Enabling and Exploiting Migratory Insertion in Base-Metal-Mediated Borylation.

Cobalt boryl complexes, which have only been sporadically reported, can be accessed systematically with remarkable (but controllable) variation in the nature of the M-B bond. Complexes incorporating a very strong trans σ-donor display unparalleled inertness, reflected in retention of the M-B bond even in the presence of extremely strong acid. By contrast, the use of the strong π-acceptor CO in the trans position, results in significant Co-B elongation and to labilization of the boryl ligand via unprecedented CO migratory insertion. Such chemistry provides a pathway for the generation of coordinative unsaturation, thereby enabling ligand substitution and/or substrate assimilation. Alkene functionalization by boryl transfer, a well-known reaction for noble metals such as Rh or Pt, can thus be effected by an 18-electron base-metal complex.

Circumventing redox chemistry: synthesis of transition metal boryl complexes from a boryl nucleophile by decarbonylation.

The very strong reducing capabilities of the boryllithium nucleophile (THF)2Li{B(NDippCH)2} (1, Dipp = 2,6-iPr2C6H3) render impractical its use for the direct introduction of the {B(NDippCH)2} ligand via metathesis chemistry into the immediate coordination sphere of transition metals (d(n), with n ≠ 0 or 10). Instead, 1 typically reacts with metal halide, amide and hydrocarbyl electrophiles either via electron transfer or halide abstraction. Evidence for the formation of M-B bonds is obtained only in the case of the d(5) system [{(HCDippN)2B}Mn(THF)(µ-Br)]2. Lower oxidation state metal carbonyl complexes such as Fe(CO)5 and Cr(CO)6 react with 1 via nucleophilic attack at the carbonyl carbon atom to give boryl-functionalized Fischer carbene complexes Fe(CO)4{C(OLi(THF)3)B(NDippCH)2} and Cr(CO)5{C(OLi(THF)2)B(NDippCH)2}. Although C-to-M boryl transfer does not occur for these formally anionic systems, more labile charge neutral bora-acyl derivatives of the type LnM{C(O)B(NDippCH)2} [LnM = Mn(CO)5, Re(CO)5, CpFe(CO)2] can be synthesized, which cleanly lose CO to generate M-B bonds. From a mechanistic standpoint, an archetypal organometallic mode of reactivity, carbonyl extrusion, has thus been shown to be applicable to the boryl ligand class, with (13)C isotopic labeling studies confirming a dissociation/migration pathway. These proof-of-methodology synthetic studies can be extended beyond boryl complexes of the group 7 and 8 metals (for which a number of versatile synthetic routes already exist) to provide access to complexes of cobalt, which have hitherto proven only sporadically accessible.

Focal cerebral ischemia after surgery in the "beach chair" position: the role of a congenital variation of circle of Willis anatomy.

A 50-year-old man underwent shoulder surgery in the beach chair position. His mean arterial blood pressure at arm level was approximately 65 mm Hg. Postoperatively, there was delayed awakening and a right hemiparesis. Radiologic evaluation revealed a congenital asymmetry of the circle of Willis that resulted in limited collateral flow to the left anterior and middle cerebral artery distributions. Similar anatomical variations are relatively common in the general population and may render some patients relatively and unpredictably more vulnerable to hypotension.

Childhood Trauma and College Sexual Harassment: Coping and Resilience as Moderators.

Childhood trauma has been identified as a risk factor for future revictimization, especially in young adulthood. There is an established link between childhood victimization and later sexual assault, but it is unclear if childhood trauma is associated with sexual harassment. Related research has examined coping and resilience as buffers, or moderators, against negative outcomes associated with childhood victimization and sexual assault, so the buffering effect of these variables will be explored for sexual harassment as well. In a sample of 583 young adults age 18-25, self-report measures of childhood trauma, sexual harassment, coping, and resilience, were collected via an online survey tool. Results of a path analysis suggest that, in general, childhood trauma places young adults at a risk for sexual harassment. Resiliency did not moderate the association between childhood trauma and sexual harassment in young adulthood, but coping did moderate this association. Specifically, when coping was high, trauma and sexual harassment were negatively related, but when coping was low to moderate, trauma and sexual harassment were positively related.

Multiple Wnts and frizzled receptors regulate anteriorly directed cell and growth cone migrations in Caenorhabditis elegans.

A set of conserved molecules guides axons along the metazoan dorsal-ventral axis. Recently, Wnt glycoproteins have been shown to guide axons along the anterior-posterior (A/P) axis of the mammalian spinal cord. Here, we show that, in the nematode Caenorhabditis elegans, multiple Wnts and Frizzled receptors regulate the anterior migrations of neurons and growth cones. Three Wnts are expressed in the tail, and at least one of these, EGL-20, functions as a repellent. We show that the MIG-1 Frizzled receptor acts in the neurons and growth cones to promote their migrations and provide genetic evidence that the Frizzleds MIG-1 and MOM-5 mediate the repulsive effects of EGL-20. While these receptors mediate the effects of EGL-20, we find that the Frizzled receptor LIN-17 can antagonize MIG-1 signaling. Our results indicate that Wnts play a key role in A/P guidance in C. elegans and employ distinct mechanisms to regulate different migrations.

A clustering of immune-mediated polyradiculoneuropathy among swine abattoir workers exposed to aerosolized porcine brains, Indiana, United States.

In November 2007 a novel neuropathy, immune-mediated polyradiculoneuropathy (IP), was identified among workers at a Minnesota swine abattoir where a unique compressed air technique was used to remove porcine brains. An epidemiologic investigation at another abattoir in Indiana that also uses this process was launched to evaluate workers self-reporting neurologic illness compatible with IP. A nested case-control study was performed to identify cases and risk factors. Six confirmed, one probable, and three possible IP cases were detected. IP cases were 28-52 years old, of Latino origin, and 62.5% female. Onset dates ranged from April 2005-December 2007; 60% were hospitalized. IP cases at this plant were similar in clinical presentation and exposure risks to those detected in Minnesota. Swine abattoirs using similar brain extraction methods should discontinue this process.

Interdisciplinary approach to all-hazards preparedness: are you ready? How do we know?

The Center for Bioterrorism and All-Hazards Preparedness (CBAP) at Nova Southeastern University College of Osteopathic Medicine is part of the National Education Strategy Team supported by the Assistant Secretary for Preparedness and Response. It developed and implemented an extensive interdisciplinary community-focused, all-hazards preparedness program as a template for use nationally. CBAP provides discipline-customized education and training experiences in emergency and disaster preparedness using multiple formats. In addition to addressing competencies that all responders must have, the CBAP National Education Strategy Team has special emphasis areas in personal planning, vulnerable and hard-to-reach populations, the employment of "cells" in the community, evidence-based evaluation including a unique casualty objective-structured clinical examination, use of student and faculty and Medical Reserve Corps volunteers, all-hazards preparedness aimed at school children, and programs addressing campus violence. CBAP emphasizes that all-hazards preparedness is an academic discipline that necessitates those trained have periodic updates to maintain their currency.

Predictable ecology and geography of West Nile virus transmission in the central United States.

West Nile virus (WNV) arrived in North America and spread rapidly through the western hemisphere. We present a series of tests to determine whether ecological factors are consistently associated with WNV transmission to humans. We analyzed human WNV cases in the states of Illinois, Indiana, and Ohio in 2002 and 2003, building ecological niche models to associate WNV case occurrences with ecological and environmental parameters. In essentially all tests, both within states, among states, between years, and across the region, we found high predictivity of WNV case distributions, suggesting that one or more elements in the WNV transmission cycle has a strong ecological determination. Areas in the geographic region included in this study predicted as suitable for WNV transmission tended to have lower values of the vegetation indices in the summer months, pointing to consistent ecological differences between suitable and unsuitable areas.

Monkeypox zoonotic associations: insights from laboratory evaluation of animals associated with the multi-state US outbreak.

At the onset of the 2003 US monkeypox outbreak, virologic data were unavailable regarding which animal species were involved with virus importation and/or subsequent transmission to humans and whether there was a risk for establishment of zoonotic monkeypox in North America. Similarly, it was unclear which specimens would be best for virus testing. Monkeypox DNA was detected in at least 33 animals, and virus was cultured from 22. Virus-positive animals included three African species associated with the importation event (giant pouched rats, Cricetomys spp.; rope squirrels, Funisciuris sp.; and dormice, Graphiuris sp.). Virologic evidence from North American prairie dogs (Cynomys sp.) was concordant with their suspected roles as vectors for human monkeypox. Multiple tissues were found suitable for DNA detection and/or virus isolation. These data extend the potential host range for monkeypox virus infection and supports concern regarding the potential for establishment in novel reservoir species and ecosystems.

Developmental Pathways of Youth Gang Membership: A Structural Test of the Social Development Model.

As a result of nearly 40 years of research using a risk and protective factor approach, much is known about the predictors of gang onset. Little theoretical work, however, has been done to situate this approach to studying gang membership within a more comprehensive developmental model. Using structural equation modeling techniques, the current study is the first to test the capacity of the social development model (SDM) to predict the developmental pathways that increase and decrease the likelihood of gang membership. Results suggest that the SDM provides a good accounting of the social developmental processes at age 13 that are predictive of later gang membership. These findings support the promotion of a theoretical understanding of gang membership that specifies both pro- and antisocial developmental pathways. Additionally, as the SDM is intended as a model that can guide preventive intervention, results also hold practical utility for designing strategies that can be implemented in early adolescence to address the likelihood of later gang involvement. Three key preventive intervention points to address gang membership are discussed, including promoting efforts to enhance social skills, increasing the availability of prosocial opportunities and rewarding engagement in these opportunities, and reducing antisocial socialization experiences throughout the middle- and high school years.

New furoquinoline alkaloid and flavanone glycoside derivatives from the leaves of Oricia suaveolens and Oricia renieri (Rutaceae).

Fractionation of the methanol extract of the leaves of Oricia renieri and Oricia suaveolens (Rutaceae) led to the isolation of 13 compounds including the hitherto unknown furoquinoline alkaloid named 6,7-methylenedioxy-5-hydroxy-8-methoxy-dictamnine (1) and a flavanone glycoside named 5-hydroxy-4'-methoxy-7-O-[α-L-rhamnopyranosyl(1‴→5″)-ß-D-apiofuranosyl]-flavanoside (2), together with 11 known compounds (3-13). The structures of the compounds were determined by comprehensive analyses of their 1D and 2D NMR, mass spectral data and comparison. All compounds isolated were examined for their activity against human carcinoma cell lines. The alkaloids 1, 5, 12, 13 and the phenolic 2, 8, 11 tested compounds exhibited non-selective moderate cytotoxic activity with IC50 8.7-15.9 µM whereas compounds 3, 4, 6, 7, 9 and 10 showed low activity.

Ethical perspectives for public and environmental health: fostering autonomy and the right to know.

In this paper we develop an ethical perspective for public and environmental health practice in consideration of the "right to know" by contrasting consequential and deontological perspectives with relational ethics grounded in the concept of fostering autonomy. From the consequential perspective, disclosure of public and environmental health risks to the public depends on the expected or possible consequences. We discuss three major concerns with this perspective: respect for persons, justice, and ignorance. From a deontological perspective, the "right to know" means that there is a "duty" to communicate about all public health risks and consideration of the principles of prevention, precaution, and environmental justice. Relational ethics develops from consideration of a mutual limitation of the traditional perspectives. Relational ethics is grounded in the relationship between the public and public/environmental health providers. In this paper we develop a model for this relationship, which we call "fostering autonomy through mutually respectful relationships." Fostering autonomy is both an end in public health practice and a means to promote the principles of prevention, precaution, and environmental justice. We discuss these principles as they relate to practical issues of major disasters and contaminants in food, such as DDT, toxaphene, chlordane, and mercury.

A large histoplasmosis outbreak among high school students in Indiana, 2001.

BACKGROUND: A histoplasmosis outbreak occurred in an Indiana high school in November-December 2001. METHODS: To describe the risk factors for this outbreak, we conducted a cohort study of all available students and staff (N = 682) and an environmental investigation. RESULTS: Of the 523 (77%) persons who displayed serologic evidence of recent Histoplasma capsulatum infection, 355 (68%) developed symptoms consistent with acute pulmonary histoplasmosis. Rototilling of soil in a school courtyard known to be a bird roosting site had been performed during school hours on November 12, 2001, 14 days before both the peak of the onset of illness and a rise in student absenteeism. Being a student (odds ratio, 3.3; 95% confidence interval, 2.2-5.0) and being a student in a classroom near the courtyard during the rototilling (odds ratio, 3.1; 95% confidence interval, 1.8-5.2) were independently associated with infection and symptomatic illness. H. capsulatum was isolated from environmental samples, including soil from the courtyard and dust collected from a filter of a heating, ventilating and air-conditioning system. CONCLUSIONS: Soil-disrupting activities within a school courtyard caused the largest outbreak to date of histoplasmosis among adolescents. Improved efforts are needed to educate the community in endemic areas about histoplasmosis to prevent the occurrence of such outbreaks in the future. In addition, increased awareness among health care providers of this disease would facilitate appropriate diagnosis and treatment.

Integrating child welfare, juvenile justice, and other agencies in a continuum of services.

This article presents a comprehensive strategy framework for integrating mental health, child welfare, education, substance abuse, and juvenile justice system services. It proposes an infrastructure of information exchange, cross-agency client referrals, a networking protocol, interagency councils, and service integration models. This infrastructure facilitates integrated service delivery.

The Developmental Dynamics of Joining a Gang in Adolescence: Patterns and Predictors of Gang Membership.

Researchers have examined the predictors of adolescent gang membership, finding significant factors in the neighborhood, family, school, peers, and individual domains. However, little is known about whether risk and protective factors differ in predictive salience at different developmental periods. The present study examines predictors of joining a gang, tests whether these factors have different effects at different ages, and whether they differ by gender using the Seattle Social Development Project (SSDP) sample (n=808). By age 19, 173 participants had joined a gang. Using survival analysis, results showed that unique predictors of gang membership onset included living with a gang member, antisocial neighborhood, and antisocial peer influences in the previous year. No time or gender interactions with predictors were statistically significant.

Comparison of the Paley method using chronological age with use of skeletal maturity for predicting mature limb length in children.

BACKGROUND: Treating patients with congenital or acquired limb-length inequality requires accurate estimations of limb length at skeletal maturity. There is controversy over the best indicator of maturity to be used for limb-length calculations. Paley popularized the multiplier method, in which chronological age is used, which has the virtue of simplicity but does not account for the wide variance in timing of the adolescent growth spurt. The purpose of this study was to determine whether the use of chronological age or the level of skeletal maturity provides more accurate limb-length predictions. METHODS: We identified patients with limb-length inequality, for whom scanograms had been obtained before and at maturity, and who had had no surgical procedures on their normal lower limb. Skeletal maturity was determined with use of the Greulich and Pyle atlas, Tanner-Whitehouse-3 method, and simplified stages described by Sanders et al. The length of the lower extremity was compared with the ultimate limb length and the actual multiplier (final limb length divided by current limb length) for each point in time. A linear model was used to determine the log-transformed multipliers for the level of skeletal maturity, and Paley's multipliers were used for chronological age. Residual standard errors were determined to compare the results of the methods. We also conducted piecewise linear regression on each of the methods and used the residual standard errors to rank their performance and cross-validated the results. RESULTS: We identified twenty-four patients (twelve girls and twelve boys) who met the study criteria. Most subjects had had multiple scanograms along with skeletal age radiographs (average, 4.5) at different ages. When all ages are considered, the Paley method had the best overall performance, with residual standard errors that were typically =5 cm. However, the Paley method did not perform best for subjects at stage-2 skeletal maturity or above; in those cases, skeletal-maturity-based predictions had residual standard errors of <2 cm. CONCLUSIONS: While the Paley method, which is based on chronological age, provides reasonable estimates of ultimate limb length for most patients, use of skeletal-maturity determinations appears to provide better predictions of mature limb length during adolescence.