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21-cm cosmology is a powerful new probe of the intergalactic medium at redshifts 20 ≳ z ≳ 6 corresponding to the Cosmic Dawn and Epoch of Reionization. Current observations of the highly-redshifted 21-cm transition are limited by the dynamic range they can achieve against foreground sources of low-frequency (<200 MHz) of radio emission. We used the Owens Valley Radio Observatory Long Wavelength Array (OVRO-LWA) to generate a series of new modern high-fidelity sky maps that capture emission on angular scales ranging from tens of degrees to ∼15 arcmin, and frequencies between 36 and 73 MHz. These sky maps were generated from the application of Tikhonov-regularized m-mode analysis imaging, which is a new interferometric imaging technique that is uniquely suited for low-frequency, wide-field, drift-scanning interferometers.
Background: Many Canadians with multiple sclerosis (MS) have recently travelled internationally to have procedures for a putative condition called chronic cerebrospinal venous insufficiency (CCSVI). Here, we describe where and when they went and describe the baseline characteristics of persons with MS who participated in this non–evidence-based medical tourism for CCSVI procedures. Methods: We conducted a longitudinal observational study that used online questionnaires to collect patient-reported information about the safety, experiences, and outcomes following procedures for CCSVI. A convenience sample of all Albertans with MS was recruited between July 2011 and March 2013. Results: In total, 868 individuals enrolled; 704 were included in this cross-sectional, baseline analysis. Of these, 128 (18.2%) participants retrospectively reported having procedures for CCSVI between April 2010 and September 2012. The proportion of participants reporting CCSVI procedures declined from 80 (62.5%) in 2010, to 40 (31.1%) in 2011, and 8 (6.3%) in 2012. In multivariable logistic regression analysis, CCSVI procedures were independently associated with longer disease duration, secondary progressive clinical course, and greater disability status. Conclusions: Although all types of people with MS pursued procedures for CCSVI, a major driver of participation was greater disability. This highlights that those with the greatest disability are the most vulnerable to unproven experimental procedures. Participation in CCSVI procedures waned over time possibly reflecting unmet expectations of treated patients, decreased media attention, or that individuals who wanted procedures had them soon after the CCSVI hypothesis was widely publicized.
A freestanding, 911-receiving emergency department was implemented at Bellevue Hospital Center during the recovery efforts after Hurricane Sandy to compensate for the increased volume experienced at nearby hospitals. Because inpatient services at several hospitals remained closed for months, emergency volume increased significantly. Thus, in collaboration with the New York State Department of Health and other partners, the Health and Hospitals Corporation and Bellevue Hospital Center opened a freestanding emergency department without on-site inpatient care. The successful operation of this facility hinged on key partnerships with emergency medical services and nearby hospitals. Also essential was the establishment of an emergency critical care ward and a system to monitor emergency department utilization at affected hospitals. The results of this experience, we believe, can provide a model for future efforts to rebuild emergency care capacity after a natural disaster such as Hurricane Sandy. (Disaster Med Public Health Preparedness. 2014;0:1-4)
The Whillans Ice Stream Subglacial Access Research Drilling (WISSARD) project will test the overarching hypothesis that an active hydrological system exists beneath a West Antarctic ice stream that exerts a major control on ice dynamics, and the metabolic and phylogenetic diversity of the microbial community in subglacial water and sediment. WISSARD will explore Subglacial Lake Whillans (SLW, unofficial name) and its outflow toward the grounding line where it is thought to enter the Ross Ice Shelf seawater cavity. Introducing microbial contamination to the subglacial environment during drilling operations could compromise environmental stewardship and the science objectives of the project, consequently we developed a set of tools and procedures to directly address these issues. WISSARD hot water drilling efforts will include a custom water treatment system designed to remove micron and sub-micron sized particles (biotic and abiotic), irradiate the drilling water with germicidal ultraviolet (UV) radiation, and pasteurize the water to reduce the viability of persisting microbial contamination. Our clean access protocols also include methods to reduce microbial contamination on the surfaces of cables/hoses and down-borehole equipment using germicidal UV exposure and chemical disinfection. This paper presents experimental data showing that our protocols will meet expectations established by international agreement between participating Antarctic nations.
Spectropolarimetric observations of HD 155806 – the hottest Galactic Oe star – were obtained with CFHT/ESPaDOnS to test the hypothesis that disk signatures in its spectrum are due to magnetic channeling and confinement of its stellar wind. We did not detect a dipole field of sufficient strength to confine the wind, and could not confirm previous reports of a magnetic detection. It appears that stellar magnetism is not responsible for producing the disk of HD 155806.
In the absence of identifiable macrofossils in lacustrine sediments, radiocarbon dating must rely on pollen or bulk sediment fractions. Bulk sediment fractions are not generally preferred because they contain an unknown mixture of organic material of variable age, they may contain dead carbon such as lignite that is difficult to eliminate, and material of aquatic origin may be subject to reservoir effects. If the various processes that contribute carbon to the system are relatively constant over time, however, changes in 14C activity with depth may be used to accurately estimate sediment accumulation rates even if the absolute ages are erroneous. In this study, fine-grained fractions (250–710 μm organic material, humic acids extracted from <250-μm fraction, and untreated <250-μm fraction combusted at low temperature) were analyzed and compared with terrestrial plant stems (twigs), charcoal, and wood fragments in sediments from an oxbow lake in Mississippi, USA. The 14C activities of the bulk fractions were highly linear with depth and produced consistent calculated sediment accumulation rates similar to, and perhaps more reliable than, rates determined using twigs or charcoal.
Strontium Titanate (STO) substrates were studied by electron paramagnetic resonance (EPR) spectroscopy to assess possible changes incurred by deposition of multiferroic thin films. To this effect, STO was vacuum annealed at pressures of 10−5 Torr for one hour at temperatures in the range of 200 – 500 °C. EPR spectra, measured before and after each anneal, revealed changes in the amount of three different defects, Cr3+, Fe3+ and an iron-oxygen vacancy complex, Fe3+Vo. The latter was used to monitor the diffusion of oxygen. EPR analysis showed that Fe3+Vo increases from its as-grown value, suggesting that a charged oxygen species is mobile in the substrate under film deposition conditions. Coupled with a subsequent O2 anneal showing minimal change in the Fe3+Vo signal, the data indicate a loss of oxygen from the sample during vacuum annealing. As charged oxygen vacancies may affect the substrate as well as the substrate/ thin film interface, these results are important for understanding the behavior of multiferroic devices built on STO substrates.
Glutamate release from photoreceptor terminals is controlled by
voltage-dependent calcium channels (VDCCs). In humans, mutations in the
Cacna1f gene, encoding the α1F subunit of VDCCs,
underlie the incomplete form of X-linked congenital stationary night
blindness (CSNB2). These mutations impair synaptic transmission from rod
and cone photoreceptors to bipolar cells. Here, we report anatomical and
functional characterizations of the retina in the nob2 (no
b-wave 2) mouse, a naturally occurring mutant caused by a null
mutation in Cacna1f. Not surprisingly, the b-waves of
both the light- and dark-adapted electroretinogram are abnormal in
nob2 mice. The outer plexiform layer (OPL) is disorganized, with
extension of ectopic neurites through the outer nuclear layer that
originate from rod bipolar and horizontal cells, but not from
hyperpolarizing bipolar cells. These ectopic neurites continue to express
mGluR6, which is frequently associated with profiles that label with the
presynaptic marker Ribeye, indicating potential points of ectopic synapse
formation. However, the morphology of the presynaptic Ribeye-positive
profiles is abnormal. While cone pedicles are present their morphology
also appears compromised. Characterizations of visual responses in retinal
ganglion cells in vivo, under photopic conditions, demonstrate
that ON-center cells have a reduced dynamic range, although their basic
center-surround organization is retained; no alteration in the responses
of OFF-center cells was evident. These results indicate that nob2
mice are a valuable model in which to explore the pathophysiological
mechanisms associated with Cacna1f mutations causing CSNB2, and
the subsequent effects on visual information processing. Further, the
nob2 mouse represents a model system in which to define the
signals that guide synapse formation and/or maintenance in the
Variation in crop–weed interference relationships has been shown for a number of crop–weed mixtures and may have an important influence on weed management decision-making. Field experiments were conducted at seven locations over 2 yr to evaluate variation in common lambsquarters interference in field corn and whether a single set of model parameters could be used to estimate corn grain yield loss throughout the northcentral United States. Two coefficients (I and A) of a rectangular hyperbola were estimated for each data set using nonlinear regression analysis. The I coefficient represents corn yield loss as weed density approaches zero, and A represents maximum percent yield loss. Estimates of both coefficients varied between years at Wisconsin, and I varied between years at Michigan. When locations with similar sample variances were combined, estimates of both I and A varied. Common lambsquarters interference caused the greatest corn yield reduction in Michigan (100%) and had the least effect in Minnesota, Nebraska, and Indiana (0% yield loss). Variation in I and A parameters resulted in variation in estimates of a single-year economic threshold (0.32 to 4.17 plants m−1 of row). Results of this study fail to support the use of a common yield loss–weed density function for all locations.
This paper is the third in a series designed to demonstrate the application of rigorous, systematic hazard identification techniques to ecological systems. Here we use Hierarchical Holographic Modelling to identify the potential ecological hazards associated with the commercial release of herbicide tolerant oilseed rape. Hierarchical Holographic Models decompose complex systems into a series of sub-systems and consider interactions between the components and processes of these sub-systems in order to identify hazards. In this example we considered 1356 potential interactions between the biological, chemical and physical components and processes of the herbicide tolerant oilseed rape environment, and identified 152 potential hazards, grouped into 14 categories. The hazards were subsequently scored for degree of concern and plausibility, and then compared with an equivalent list of hazards generated independently by a checklist approach. The incidence of herbicide tolerant volunteers (and weeds) both on and off the farm had the highest average score of all the ecological hazard categories. The checklist based approach identified or implied 44% of the hazards identified in the Hierarchical Holographic Model, including nine of the ten hazards ranked most important. The checklist approach focussed almost exclusively on the phenotypic and genotypic hazards associated with herbicide tolerant oilseed rape and largely ignored the hazards associated with the circumstances surrounding its use. As a result the checklist identified only 6 out of the 79 potential hazards associated with changes to farming practice. The commercial release of herbicide tolerant oilseed rape will be associated with changes in tillage and the application of post-emergent herbicides. It may also lead to changes in spray schedules of insecticide and fungicide. Many of the environmental hazards identified with these changes are plausible and may warrant further investigation or targeted monitoring.
The Holocene portion of the Siple Dome (Antarctica) ice core was dated by interpreting the electrical, visual and chemical properties of the core. The data were interpreted manually and with a computer algorithm. The algorithm interpretation was adjusted to be consistent with atmospheric methane stratigraphic ties to the GISP2 (Greenland Ice Sheet Project 2) ice core, 10Be stratigraphic ties to the dendrochronology 14 C record and the dated volcanic stratigraphy. The algorithm interpretation is more consistent and better quantified than the tedious and subjective manual interpretation.
We measured vertical strain in the firn at Siple Dome, Antarctica, using two systems, both of which measure relative displacements over time of metal markers placed in an air-filled borehole. One system uses a metal-detecting tuned coil, and the other uses a video camera to locate the markers. We compare the merits of the two systems. We combine steady-state calculations and a measured density profile to estimate the true vertical-velocity profile. This allows us to calculate a depth-age scale for the firn at Siple Dome. Our steady-state depth-age scale has ages ≈10-15% younger at any given depth when compared to depth-age scales derived by layer counting in a core 40 m away. The age of a visible ash layer at 97 m in the core is 665 ± 30 years, in agreement with a similar analysis conducted at Taylor Dome, Antarctica, where the same ash is also seen, providing an additional dated tie point between the two cores.
We have constructed an oblique-incidence reflectivity difference (OI-RD) microscope for fluorescent label-free imaging of DNA and protein microarrays on standard glass substrates. Using both OI-RD and fluorescence images, we demonstrate a difference in wetting behavior of labeled and unlabeled IgG protein molecules deposited on an aldehyde-derivatized glass surface. The potential of fluorescent labeling agents to influence the properties of proteins highlights the need for label-free microarray detection techniques to supplement existing fluorescence methods. We also present OI-RD images of an oligonucleotide microarray after printing and washing procedures to demonstrate the use of OI-RD for non-destructive monitoring of changes in the optical properties of microarrays during processing.
The study sought to quantify psychiatric morbidity among survivors of a major air crash and to identify aetiological factors linked with post-traumatic stress disorder (PTSD).
Sixty-eight of the 79 survivors (86%) were assessed at a clinical interview within one year of the disaster. The majority also completed the General Health Questionnaire, the Impact of Events Scale (IES) and the Zung Anxiety and Depression Scales.
Fifty-four of the study group (79%) met DSM–III–R criteria for a psychiatric disorder within one year of the disaster, of whom 27 (50%) had PTSD. Those who saw injured or dead people at the scene, or had sustained less severe injuries as measured by their Injury Severity Scores, or were under 35 years old, were significantly more likely to develop PTSD.
High rates of psychiatric morbidity are found in survivors of transportation disasters. Further studies are needed to identify those at most risk and to evaluate the benefits of psychological intervention.
This paper suggests that the seventh century Chinese Śūraṅgama Sūtra may be relevant in attempting to understand various historical and philosophical aspects of the Japanese Fuke sect of Zen Buddhism and its practice of shakuhachi playing as a spiritual exercise. While the Śūraraṅgama Sūtra cannot be regarded as a direct source of the spiritual practice of shakuhachi in Fuke Zen, it nonetheless provides an historically and conceptually relevant basis for understanding some religious and philosophical ideas of the Zen shakuhachi tradition. The sutra's historical origins and close identification with the Zen tradition in China and Japan are discussed, and the concept of a meditation on sound expounded in this sutra is examined.
In my studies of the use of the Japanese shakuhachi in the Fuke sect of Zen Buddhism, I have been continually puzzled by the tradition which traces the playing of shakuhachi as a religious practice back to the T'ang period Chinese Zen (Chinese: Ch'an) figure P'u-hua (read Fuke in Japanese). This tradition, recorded in the middle Edo period source Kyotaku Denki but certainly much older, does not attempt to ascribe to Fuke either the playing of shakuhachi or any knowledge of it whatsoever. Indeed Fuke's only musical connection was his ringing of a bell as he wandered the streets, the sound of which is said to have been captured after his death by a shakuhachi-playing disciple, Chang Po, and turned into the first piece of the Fuke repertoire, Kyotaku. It is now generally accepted that this history was largely fabricated in order to legitimize the Fuke sect, by establishing an elaborate genealogy leading back to the very source of the Zen tradition in Tang period China and to a figure (Fuke) traditionally associated with Rinzai Gigen (Chinese: Lin Chi I-hsüan), one of the great figures of early Zen.
Metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide] toxicity, absorption, translocation, and metabolism were investigated in corn (Zea mays L.) and yellow nutsedge (Cyperus esculentus L.). Metolachlor did not inhibit seed germination in corn or tuber germination in yellow nutsedge. It did not kill yellow nutsedge tubers that were exposed to 4 ppmw for 9 weeks. Metolachlor (10 ppmw) applied in soil above the seed significantly reduced corn shoot growth, but the same concentration around or below the seed had no effect. A soil mixture with metolachlor (1 ppmw) placed above or around yellow nutsedge tubers significantly reduced shoot growth, but placement around the tuber was the most toxic; placement below the tuber had no effect on shoot growth. The concentration of metolachlor that resulted in 50% reduction of shoot growth of 4-day-old seedlings in solution culture was > 10−4 M for corn and <10−6M for yellow nutsedge. Root-applied 14C-metolachlor was acropetally translocated to shoots of both species following a 7- to 13-day absorption period, with yellow nutsedge translocating the highest portion of the absorbed material to shoots. In 2-day-old seedlings with roots exposed to 14C-metolachlor for up to 48 h, both species absorbed and translocated the radioactivity to shoots, but corn absorbed much more than yellow nutsedge. When the 14C-metolachlor was applied to shoots of both species, the radioactivity was translocated basipetally into roots. Yellow nutsedge exuded appreciable 14C-metolachlor out of the roots and absorbed more 14C-metolachlor through shoot tissues than corn. Both corn and yellow nutsedge seedlings readily converted the 14C-metolachlor to metabolites, but corn was able to metabolize the 14C-metolachlor at a faster rate than yellow nutsedge and also produced more metabolites.
It is the purpose of this article to examine the role which the three regional economic commissions of the United Nations serving the developing world play, whether consciously or unconsciously, in promoting integration within the regions which they serve. The emphasis is upon economic integration, not because it is more important than political union or federation or because it is a necessary antecedent to political integration. No attempt is made here to establish the thesis that the relationship between economic and political integration is that of a continuum. Any contribution which the UN regional economic commissions make to regional or sub-regional integration will almost certainly be in the economic area, given their terms of reference, the nature of their work programs, and the environmental conditions in which they operate. Economic integration resulting from ideas and initiatives originating in the regional commissions may contribute to the evolution of political union.