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The current study examined whether social status and social integration, two related but distinct indicators of an adolescent's standing within a peer network, mediate the association between risky symptoms (depressive symptoms and deviant behavior) and substance use across adolescence. The sample of 6,776 adolescents participated in up to seven waves of data collection spanning 6th to 12th grades. Scores indexing social status and integration were derived from a social network analysis of six schools and subsequent psychometric modeling. Results of latent growth models showed that social integration and status mediated the relation between risky symptoms and substance use and that risky symptoms mediated the relation between social standing and substance use during the high school transition. Before this transition, pathways involving deviant behavior led to high social integration and status and in turn to substance use. After this transition, both deviant behavior and depressive symptoms led to low social integration and status and in turn greater substance use. These findings suggest that the high school transition is a risky time for substance use related to the interplay of increases in depressive symptoms and deviant behavior on the one hand and decreases in social status and integration on the other.
The association between lower birth weight and increased disease risk in adulthood has drawn attention to the physiological processes that shape the gestational environment. We implement genome-wide transcriptional profiling of maternal blood samples to identify subsets of genes and associated transcription control pathways that predict offspring birth weight. Female participants (N = 178, mean = 27.0 years) in a prospective observational birth cohort study were contacted between 2009 and 2014 to identify new pregnancies. An in-home interview was scheduled for early in the third trimester (mean = 30.3 weeks) to collect pregnancy-related information and a blood sample, and birth weight was measured shortly after delivery. Transcriptional activity in white blood cells was determined with a whole-genome gene expression direct hybridization assay. Fifty transcripts were differentially expressed in association with offspring birth weight, with 18 up-regulated in relation to lower birth weight, and 32 down-regulated. Examination of transcription control pathways identified increased activity of NF-κB, AP-1, EGR1, EGR4, and Gfi families, and reduced the activity of CEBP, in association with lower birth weight. Transcript origin analyses identified non-classical CD16+ monocytes, CD1c+ myeloid dendritic cells, and neutrophils as the primary cellular mediators of differential gene expression. These results point toward a systematic regulatory shift in maternal white blood cell activity in association with lower offspring birth weight, and they suggest that analyses of gene expression during gestation may provide insight into regulatory and cellular mechanisms that influence birth outcomes.
As the Environmental Protection Agency adds ever more sites to the National Priorities List for Superfund clean-up, there is a tremendous need for a fast method of screening for contaminants. In the case of inorganics, we can apply field-portable X-ray fluorescence technology.
With commercially available field-portable X-ray fluorescence equipment using in-situ measurements we can quickly screen a site (hundreds of measurements), input the data to a portable computer, process it, and print a colored concentration isopleth map of the contaminant of interest, all in realtime.
The in-situ measurement approach pioneered by Lockheed is the key to rapid screening capability. Problems arising from particle size distribution, soil heterogeneity, and bulk density are minimized by employing site-specific standards in the construction of our calibration curves. Inherent in these site-specific standards are all the matrix problems which occur in the routine samples.
The strength of field-portable X-ray fluorescence technology is the accuracy of analysis above the quantitation limits. The difficulty in measuring low concentrations near the detection limit is the weak point of field-portable units.
NOTICE: Although this research was funded in part by the U.S. EPA through Contract 68-03-3249 to Lockheed Engineering & Sciences Company, it has not undergone Agency review and does not necessarily reflect Agency policy.
Plain carbon steels are primarily composed of iron (~97%), but generally have small quantities of carbon, manganese, sulfur, phosphorous and silicon also present. Lead or copper may also be present. The steel industry is in need of an on-line technique of analysis for manganese in these steels. The manganese concentration of these steels varies from 0.3 to 1.5%. A technique is presented for the rapid analysis of manganese in carbon steels using energy dispersive x-ray fluorescence spectroscopy. It is capable of determining the manganese content of a carbon steel in. less than 30 sec with an uncertainty of less than 0.05% manganese. Because this method can analyze a steel from a distance of two feet, it should be possible to adequately protect the x-ray fluorescence spectrometer from the environment even when analyses are made of hot steel ingots at temperatures ranging up to 2400°F.
To evaluate whole-genome sequencing (WGS) as a molecular typing tool for MRSA outbreak investigation.
Investigation of MRSA colonization/infection in a neonatal intensive care unit (NICU) over 3 years (2014–2017).
Single-center level IV NICU.
NICU infants and healthcare workers (HCWs).
Infants were screened for MRSA using a swab of the anterior nares, axilla, and groin, initially by targeted (ring) screening, and later by universal weekly screening. Clinical cultures were collected as indicated. HCWs were screened once using swabs of the anterior nares. MRSA isolates were typed using WGS with core-genome multilocus sequence typing (cgMLST) analysis and by pulsed-field gel electrophoresis (PFGE). Colonized and infected infants and HCWs were decolonized. Control strategies included reinforcement of hand hygiene, use of contact precautions, cohorting, enhanced environmental cleaning, and remodeling of the NICU.
We identified 64 MRSA-positive infants: 53 (83%) by screening and 11 (17%) by clinical cultures. Of 85 screened HCWs, 5 (6%) were MRSA positive. WGS of MRSA isolates identified 2 large clusters (WGS groups 1 and 2), 1 small cluster (WGS group 3), and 8 unrelated isolates. PFGE failed to distinguish WGS group 2 and 3 isolates. WGS groups 1 and 2 were codistributed over time. HCW MRSA isolates were primarily in WGS group 1. New infant MRSA cases declined after implementation of the control interventions.
We identified 2 contemporaneous MRSA outbreaks alongside sporadic cases in a NICU. WGS was used to determine strain relatedness at a higher resolution than PFGE and was useful in guiding efforts to control MRSA transmission.
Timing of weed emergence and seed persistence in the soil influence the ability to implement timely and effective control practices. Emergence patterns and seed persistence of kochia populations were monitored in 2010 and 2011 at sites in Kansas, Colorado, Wyoming, Nebraska, and South Dakota. Weekly observations of emergence were initiated in March and continued until no new emergence occurred. Seed was harvested from each site, placed into 100-seed mesh packets, and buried at depths of 0, 2.5, and 10 cm in fall of 2010 and 2011. Packets were exhumed at 6-mo intervals over 2 yr. Viability of exhumed seeds was evaluated. Nonlinear mixed-effects Weibull models were fit to cumulative emergence (%) across growing degree days (GDD) and to viable seed (%) across burial time to describe their fixed and random effects across site-years. Final emergence densities varied among site-years and ranged from as few as 4 to almost 380,000 seedlings m−2. Across 11 site-years in Kansas, cumulative GDD needed for 10% emergence were 168, while across 6 site-years in Wyoming and Nebraska, only 90 GDD were needed; on the calendar, this date shifted from early to late March. The majority (>95%) of kochia seed did not persist for more than 2 yr. Remaining seed viability was generally >80% when seeds were exhumed within 6 mo after burial in March, and declined to <5% by October of the first year after burial. Burial did not appear to increase or decrease seed viability over time but placed seed in a position from which seedling emergence would not be possible. High seedling emergence that occurs very early in the spring emphasizes the need for fall or early spring PRE weed control such as tillage, herbicides, and cover crops, while continued emergence into midsummer emphasizes the need for extended periods of kochia management.
High conflict and low warmth in families may contribute to immune cells developing a tendency to respond to threats with exaggerated inflammation that is insensitive to inhibitory signaling. We tested associations between family environments and expression of genes bearing response elements for transcription factors that regulate inflammation: nuclear factor kappa B (NF-κB) and glucocorticoid receptor. The overall sample (47 families) completed interviews, questionnaires, and 8-week daily diary assessments of conflict and warmth, which were used to create composite family conflict and warmth scores. The diaries assessed upper respiratory infection (URI) symptoms, and URI episodes were clinically verified. Leukocyte RNA was extracted from whole blood samples provided by a subsample of 42 children (8–13 years of age) and 73 parents. In children, higher conflict and lower warmth were related to greater expression of genes bearing response elements for the proinflammatory transcription factor NF-κB, and more severe URI symptoms. In parents, higher conflict and lower warmth were also related to greater NF-κB–associated gene expression. Monocytes and dendritic cells were implicated as primary cellular sources of differential gene expression in the sample. Consistent with existing conceptual frameworks, stressful family environments were related to a proinflammatory phenotype at the level of the circulating leukocyte transcriptome.
This short note describes the equipment and procedures we have developed to mount end caps on ice-core specimens. The system typically achieves end-plane parallelism within 0.5 μm/mm of specimen diameter (i.e. a total indicator run-out of 0.002 in for a 4.0 in diameter specimen). The essential elements of the system are a holder and an alignment fixture. The holder firmly grips the ice core about its circumference by the compression of two series of O–rings. The alignment fixture clamps the holder to align the ice core precisely with the end caps. To bond the ice to the end cap we form a layer of 0°C water on the end cap; the water freezes immediately upon contact with the ice and forms a strong intimate bond. To date, we have used this system to install phenolic end caps on 101.6 mm diameter cores and aluminum end caps on 76.2 mm diameter cores of saline ice. We obtained a somewhat better tolerance with the aluminum caps (0.33 μm/mm of end-cap diameter), due primarily to the geometric stability of that material under the prevailing conditions. These specimens have been successfully tested in uniaxial and triaxial compression, and we expect that with appropriate end caps the system will be suitable for preparing tension specimens as well.
We studied neuroinflammation in individuals with late-life, depression, as a
risk factor for dementia, using [11C]PK11195 positron emission
tomography (PET). Five older participants with major depression and 13
controls underwent PET and multimodal 3T magnetic resonance imaging (MRI),
with blood taken to measure C-reactive protein (CRP). We found significantly
higher CRP levels in those with late-life depression and raised
[11C]PK11195 binding compared with controls in brain regions
associated with depression, including subgenual anterior cingulate cortex,
and significant hippocampal subfield atrophy in cornu ammonis 1 and
subiculum. Our findings suggest neuroinflammation requires further
investigation in late-life depression, both as a possible aetiological
factor and a potential therapeutic target.
Profound agitation in the prehospital setting confers substantial risk to patients and providers. Optimal chemical sedation in this setting remains unclear.
The goal of this study was to describe intubation rates among profoundly agitated patients treated with prehospital ketamine and to characterize clinically significant outcomes of a prehospital ketamine protocol.
This was a retrospective cohort study of all patients who received prehospital ketamine, per a predefined protocol, for control of profound agitation and who subsequently were transported to an urban Level 1 trauma center from May 1, 2010 through August 31, 2013. Identified records were reviewed for basic ambulance run information, subject characteristics, ketamine dosing, and rate of intubation. Emergency Medical Services (EMS) ambulance run data were matched to hospital-based electronic medical records. Clinically significant outcomes are characterized, including unadjusted and adjusted rates of intubation.
Overall, ketamine was administered 227 times in the prehospital setting with 135 cases meeting study criteria of use of ketamine for treatment of agitation. Endotracheal intubation was undertaken for 63% (85/135) of patients, including attempted prehospital intubation in four cases. Male gender and late night arrival were associated with intubation in univariate analyses (χ2=12.02; P=.001 and χ2=5.34; P=.021, respectively). Neither ketamine dose, co-administration of additional sedating medications, nor evidence of ethanol (ETOH) or sympathomimetic ingestion was associated with intubation. The association between intubation and both male gender and late night emergency department (ED) arrival persisted in multivariate analysis. Neither higher dose (>5mg/kg) ketamine nor co-administration of midazolam or haloperidol was associated with intubation in logistic regression modeling of the 120 subjects with weights recorded. Two deaths were observed. Post-hoc analysis of intubation rates suggested a high degree of provider-dependent variability.
Prehospital ketamine is associated with a high rate of endotracheal intubation in profoundly agitated patients; however, ketamine dosing is not associated with intubation rate when adjusted for potential confounders. It is likely that factors not included in this analysis, including both provider comfort with post-ketamine patients and anticipated clinical course, play a role in the decision to intubate patients who receive prehospital ketamine.
OlivesTD, NystromPC, ColeJB, DoddKW, HoJD. Intubation of Profoundly Agitated Patients Treated with Prehospital Ketamine. Prehosp Disaster Med. 2016;31(6):593–602.
Aperture synthesis is a two-step imaging process in which the final map or image is reconstructed from intermediate measurements. As an alternative to digital computers, optical computers can be used to perform the reconstruction step. Optical reconstruction can be a fast and cheap way to handle the large amount of data now being generated by earth rotation aperture synthesis arrays.
From early experiments in 1966 (Cole 1968) the acousto-optical radio spectrograph has been developed at CSIRO to a sensitive, multi-channel spectral-line back-end. The principles of the instrument are described in detail elsewhere (Lambert 1962; Hecht 1977; Milne and Cole 1977). By means of a Bragg interaction between a laser beam and an ultrasonic beam derived from the radio signal, light is diffracted into an order whose light intensity distribution is accurately related to the power spectrum of the radio signal. In the earlier spectrographs the spectrum was recorded photographically (Cole 1973a, b; Hecht 1973) but this was limited to strong spectral features. To study weak spectral features a stable, linear system was needed with large dynamic range. The combination of an array of photodiodes and computer would be capable of observing these weak spectral features (Cole and Abies 1974). Development since 1974 has been a progressive identification of sources of thermal and mechanical instability and of excess noise in the spectrograph system.
Interesting observations have been made possible by the success of the acousto-optical radio spectrograph, a unique form of multi-channel filter type of spectral receiver whose channel outputs ian be sampled at high rates by a computer. Three spectrographs are available at the Division of Radiophysics. Two divide a 100 MHz spectral range into 512 channels and are normally dedicated to spectral-line work (Cole and Milne 1977) and solar work (Cole et al. 1978). The Parkes observations reported here use a more compact spectrograph, which gives increased performance — up to 270 MHz can be studied, divided into 256 frequency channels. The light deflector of this spectrograph was kindly supplied by Itek Corporation.
In science we have good, successful laboratories and scientists and we also have wasteful, inefficient and unproductive ones. The differences are not matters of chance.
It is not an accident that just one Cambridge College, Trinity, has achieved more Nobel Prizes than all of Japan. There was something in common amongst the Nobel prize winners Todd, Adrian, Perutz, Bragg, Crick, Ryle, Hewish and Mott that I was fortunate enough to meet and, in some cases, get to know well. Of course there was the personal and intellectual calibre of these people, their drive and determination. But also, there was the laboratory culture within which they worked, a culture still benefiting from the influence of Maxwell, Thomson and Rutherford.
The discovery of pulsars in 1967 marked the watershed of interest in short-time-scale phenomena in radio astronomy. Ionospheric scintillation on time scales of seconds, interplanetary scintillations at tenths of seconds and solar bursts of similar duration had already been studied. But with pulsars individual pulses contained subpulses of width about 10 ms, and later observations of microstructure were to show that structure with scales of 10—100 μs were present. In other areas searches for the 10—100 ms radio pulses expected to accompany the gravitational wave events resulting from stellar collapses were made, and more recently searches have been made for the radio pulse accompanying the explosion of small black holes (Rees 1977). Work in this area is summarized by O’Sullivan et al. (1978) and Phinney and Taylor (1979).
Speckle interferometry (Labeyrie 1970, 1976) is one way of overcoming the blurring effect of the atmosphere in optical astronomy. When a short exposure is taken of an image, the seeing disc (typically several seconds of arc across) is seen to contain structure (speckles) down to the resolution limit of the telescope (0″.03 arc for the Anglo-Australian telescope). A second exposure 10 or so milliseconds later will show a different pattern of structure because the atmospheric irregularities will have changed. Multiple stars or source components within the same angular range of atmospheric irregularity (i.e. isoplanatic patch several seconds of arc across) will produce similar but displaced speckle patterns, and geometrical details of the components can be obtained from an autocorrelation analysis of the speckle pattern (Dainty 1975).
Research was conducted from 2011 to 2014 to determine weed population dynamics and frequency of glyphosate-resistant (GR) Palmer amaranth with herbicide programs consisting of glyphosate, dicamba, and residual herbicides in dicamba-tolerant cotton. Five treatments were maintained in the same plots over the duration of the experiment: three sequential POST applications of glyphosate with or without pendimethalin plus diuron PRE; three sequential POST applications of glyphosate plus dicamba with and without the PRE herbicides; and a POST application of glyphosate plus dicamba plus acetochlor followed by one or two POST applications of glyphosate plus dicamba without PRE herbicides. Additional treatments included alternating years with three sequential POST applications of glyphosate only and glyphosate plus dicamba POST with and without PRE herbicides. The greatest population of Palmer amaranth was observed when glyphosate was the only POST herbicide throughout the experiment. Although diuron plus pendimethalin PRE in a program with only glyphosate POST improved control during the first 2 yr, these herbicides were ineffective by the final 2 yr on the basis of weed counts from soil cores. The lowest population of Palmer amaranth was observed when glyphosate plus dicamba were applied regardless of PRE herbicides or inclusion of acetochlor POST. Frequency of GR Palmer amaranth was 8% or less when the experiment was initiated. Frequency of GR Palmer amaranth varied by herbicide program during 2012 but was similar among all herbicide programs in 2013 and 2014. Similar frequency of GR Palmer amaranth across all treatments at the end of the experiment most likely resulted from pollen movement from Palmer amaranth treated with glyphosate only to any surviving female plants regardless of PRE or POST treatment. These data suggest that GR Palmer amaranth can be controlled by dicamba and that dicamba is an effective alternative mode of action to glyphosate in fields where GR Palmer amaranth exists.