1,691 research outputs found
A new species of Conoryctella (Mammalia: Taeniodonta) from the Paleocene of the San Juan Basin, New Mexico, and a revision of the genus
Specimens from Paleocene strata of the Nacimiento Formation in Kutz Canyon, San Juan Basin, New Mexico, add to our knowledge of the poorly known taeniodont genus Conoryctella Gazin, 1939 and provide evidence for its taxonomic revision. C. dragonensis Gazin, 1939 is only known with certainty from its type specimen from the Dragon local fauna, North Horn Formation in east-central Utah, although a poorly preserved maxillary fragment and canine of uncertain provenance from the San Juan Basin, New Mexico, may pertain to this taxon. C. pattersoni, new species, differs from C. dragonensis in its smaller size, less molariform P4 and relatively narrow upper molars. It is known from: dental remains from the Dragon local fauna previously referred to C. dragonensis by Gazin (1939, 1941); dental remains from Torrejonian strata in Kutz Canyon referred by Wilson (1956, p. 82) to conoryctine, n. gen. and sp. ; and newly discovered dental and postcranial remains from a horizon in Kutz Canyon that, based on magnetostratigraphy (Tomida and Butler, 1980), is temporally equivalent to the Dragon local fauna. The occurrences of Conoryctella in the San Juan Basin extend the geographic range of the genus and also extend its time-stratigraphic range into a typical Torrejonian horizon. These extensions further reduce the distinctiveness of the Dragon local fauna, supporting recent arguments that the Dragon local fauna should be considered early Torrejonian in age
Coordination and Sustainability of River Observing Activities in the Arctic
To understand and respond to changes in the world’s northern regions, we need a coordinated system of long-term Arctic observations. River networks naturally integrate across landscapes and link the terrestrial and ocean domains. Changes in river discharge reflect changes in the terrestrial water balance, whereas changes in water chemistry are linked to changes in biogeochemical processes and water flow paths. Sustained measurements of river water discharge and water chemistry are therefore essential components of an Arctic observing network. As we strive to establish and sustain long-term observations in the Arctic, these two measurements must be coupled. Although river discharge and chemistry measurements are already coupled to some extent within national boundaries, this is not done in a consistent and coordinated fashion across the pan-Arctic domain. As a consequence, data quality and availability vary widely among regions. International coordination of river discharge and chemistry measurements in the Arctic would be greatly facilitated by formal commitments to maintain a set of core sites and associated measurements that are mutually agreed upon among pan-Arctic nations. Involvement of the agencies currently operating river discharge gauges around the Arctic and establishment of an overarching coordination entity to implement shared protocols, track data quality, and manage data streams would be essential in this endeavor. Focused studies addressing scale-dependent relationships between watershed characteristics and water chemistry, in-stream processes, and estuarine and coastal dynamics are also needed to support interpretation and application of Arctic river observing data as they relate to land and ocean change
A Guide to the Kenya National Archives
The Guide is a compilation of 6 sections accessing approximately 157 microfilm reels of documents within the collection of the Kenya National Archives.https://surface.syr.edu/books/1005/thumbnail.jp
A Guide to the Kenya National Archives to the Microfilms of the Provincial and District Annual Reports, Record Books, and Handing-Over Reports; Miscellaneous Correspondence; and Intelligence Reports
The Guide is a compilation of 6 sections accessing approximately 157 microfilm reels of documents within the collection of the Kenya National Archives. Documents in the collection include archival material of the British colonial government in Kenya up to the mid 1960’s.
For more information, refer to the Kenya National Archives subject guide.https://surface.syr.edu/archiveguidekenya/1000/thumbnail.jp
A Guide to the Kenya National Archives to the Microfilms of the Provincial and District Annual Reports, Record Books, and Handing-Over Reports; Miscellaneous Correspondence; and Intelligence Reports
The Guide is a compilation of 6 sections accessing approximately 157 microfilm reels of documents within the collection of the Kenya National Archives
A new baenid turtle from the early Paleocene (Torrejonian) of New Mexico and a species-level phylogenetic analysis of Baenidae
New cranial and postcranial material of the baenid turtle Neurankylus from the Paleocene Nacimiento Formation (Torrejonian NALMA) of northwestern New Mexico represents a new species, Neurankylus torrejonensis. The material consists of a fragmented but mostly complete skull, a partial carapace and plastron, portions of both humeri, a partial pelvis, a complete right femur, and a distal phalanx. The small, undivided cervical scale, wide vertebrals, complete ring of marginals, and large size (carapace length 520 mm) diagnose the new taxon as belonging to Neurankylus. The narrow fifth vertebral scale and scalloped posterior shell margin reveal affinities with Neurankylus baueri Gilmore, 1916, which is known from Campanian sediments in New Mexico and Utah. The holotype of Neurankylus torrejonensis is the youngest known specimen of the Neurankylus lineage, which is known to reach at least back to the Late Cretaceous (Santonian). A nearly complete species-level analysis of baenids confirms the basal placement of Neurankylus outside of Baenodda and the split of Baenodda into two primary subclades, herein named Palatobaeninae and Eubaeninae
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Left auditory cortex gamma synchronization and auditory hallucination symptoms in schizophrenia
<p>Abstract</p> <p>Background</p> <p>Oscillatory electroencephalogram (EEG) abnormalities may reflect neural circuit dysfunction in neuropsychiatric disorders. Previously we have found positive correlations between the phase synchronization of beta and gamma oscillations and hallucination symptoms in schizophrenia patients. These findings suggest that the propensity for hallucinations is associated with an increased tendency for neural circuits in sensory cortex to enter states of oscillatory synchrony. Here we tested this hypothesis by examining whether the 40 Hz auditory steady-state response (ASSR) generated in the left primary auditory cortex is positively correlated with auditory hallucination symptoms in schizophrenia. We also examined whether the 40 Hz ASSR deficit in schizophrenia was associated with cross-frequency interactions.</p> <p>Sixteen healthy control subjects (HC) and 18 chronic schizophrenia patients (SZ) listened to 40 Hz binaural click trains. The EEG was recorded from 60 electrodes and average-referenced offline. A 5-dipole model was fit from the HC grand average ASSR, with 2 pairs of superior temporal dipoles and a deep midline dipole. Time-frequency decomposition was performed on the scalp EEG and source data.</p> <p>Results</p> <p>Phase locking factor (PLF) and evoked power were reduced in SZ at fronto-central electrodes, replicating prior findings. PLF was reduced in SZ for non-homologous right and left hemisphere sources. Left hemisphere source PLF in SZ was positively correlated with auditory hallucination symptoms, and was modulated by delta phase. Furthermore, the correlations between source evoked power and PLF found in HC was reduced in SZ for the LH sources.</p> <p>Conclusion</p> <p>These findings suggest that differential neural circuit abnormalities may be present in the left and right auditory cortices in schizophrenia. In addition, they provide further support for the hypothesis that hallucinations are related to cortical hyperexcitability, which is manifested by an increased propensity for high-frequency synchronization in modality-specific cortical areas.</p
Permafrost degradation and nitrogen cycling in Arctic rivers: Insights from stable nitrogen isotope studies
Abstract. Across the Arctic, vast areas of permafrost are being degraded by climate
change, which has the potential to release substantial quantities of
nutrients, including nitrogen into large Arctic rivers. These rivers heavily
influence the biogeochemistry of the Arctic Ocean, so it is important to
understand the potential changes to rivers from permafrost degradation. This
study utilized dissolved nitrogen species (nitrate and dissolved organic
nitrogen (DON)) along with nitrogen isotope values (δ15N-NO3- and δ15N-DON) of samples collected
from permafrost sites in the Kolyma River and the six largest Arctic rivers.
Large inputs of DON and nitrate with a unique isotopically heavy δ15N signature were documented in the Kolyma, suggesting the occurrence
of denitrification and highly invigorated nitrogen cycling in the Yedoma
permafrost thaw zones along the Kolyma. We show evidence for permafrost-derived DON being recycled to nitrate as it passes through the river,
transferring the high 15N signature to nitrate. However, the potential
to observe these thaw signals at the mouths of rivers depends on the spatial
scale of thaw sites, permafrost degradation, and recycling mechanisms. In
contrast with the Kolyma, with near 100 % continuous permafrost extent,
the Ob River, draining large areas of discontinuous and sporadic
permafrost, shows large seasonal changes in both nitrate and DON isotopic
signatures. During winter months, water percolating through peat soils
records isotopically heavy denitrification signals in contrast with the
lighter summer values when surface flow dominates. This early year
denitrification signal was present to a degree in the Kolyma, but the ability
to relate seasonal nitrogen signals across Arctic Rivers to permafrost
degradation could not be shown with this study. Other large rivers in the
Arctic show different seasonal nitrogen trends. Based on nitrogen isotope
values, the vast majority of nitrogen fluxes in the Arctic rivers is from
fresh DON sourced from surface runoff through organic-rich topsoil and not
from permafrost degradation. However, with future permafrost thaw, other
Arctic rivers may begin to show nitrogen trends similar to the Ob. Our
study demonstrates that nitrogen inputs from permafrost thaw can be
identified through nitrogen isotopes, but only on small spatial scales.
Overall, nitrogen isotopes show potential for revealing integrated catchment
wide nitrogen cycling processes.
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Management of Peritonsillar Abscess Within a Local Emergency Department: A Quality Analysis Study.
OBJECTIVE: Peritonsillar abscess (PTA) is the most common deep space infection of the head and neck, affecting thousands of people annually with high treatment costs. The purpose of this project was to determine how in-network emergency departments (EDs) adhere to generally accepted guidelines regarding diagnosis and management of potential PTAs.
METHODS: The authors performed a retrospective chart review to identify patients with PTA in five EDs in one year. Information pertaining to diagnostic tests, treatment, and airway status was also collected. Descriptive analysis was used to assess if EDs were consistent with generally accepted guidelines.
RESULTS: Six hundred twenty-one patient records were identified and 140 were included in final analysis. Out of 140 patients, 71 were admitted for inpatient management and 23 were admitted for observation. Of the 46 patients diagnosed and discharged from the ED, 61% received a computerized tomography (CT) scan and only 39% had PTA drainage performed. Four (3%) patients received a point of care ultrasound and a CT scan and no patient received only an ultrasound. Out of all patients, 116/140 received a CT scan and 22 received drainage in the ED. The remainder of these patients either had drainage performed by an otolaryngologist or had no drainage performed. Of the 94 patients admitted for inpatient or observation, 84 received a CT scan and six received drainage by an ED physician. Only 62% of patients were given a penicillin derivative and 29% were given clindamycin, which has no Gram-negative coverage.
CONCLUSION: One-third of PTA patients were managed within the ED, far less than similar studies. Of these, over 50% received a CT scan and less than 50% had PTA drainage. PTA drainage can improve patients\u27 symptoms and antibiotic effectiveness. The majority of patients were prescribed a penicillin derivative with or without another antibiotic
Exploring Aerosols near Clouds with High-Spatial-Resolution Aircraft Remote Sensing During SEAC4RS
Since aerosols are important to our climate system, we seek to observe the variability of aerosol properties within cloud systems. When applied to the satelliteborne Moderateresolution Imaging Spectroradiometer (MODIS), the Dark Target retrieval algorithm provides global aerosol optical depth (AOD; at 0.55 m) in cloudfree scenes. Since MODIS' resolution (500m pixels, 3 or 10km product) is too coarse for studying nearcloud aerosol, we ported the Dark Target algorithm to the highresolution (~50m pixels) enhancedMODIS Airborne Simulator (eMAS), which flew on the highaltitude ER2 during the Studies of Emissions, Atmospheric Composition, Clouds, and Climate Coupling by Regional Surveys Airborne Science Campaign over the United States in 2013. We find that even with aggressive cloud screening, the ~0.5km eMAS retrievals show enhanced AOD, especially within 6 km of a detected cloud. To determine the cause of the enhanced AOD, we analyze additional eMAS products (cloud retrievals and degradedresolution AOD), coregistered Cloud Physics Lidar profiles, MODIS aerosol retrievals, and groundbased Aerosol Robotic Network observations. We also define spatial metrics to indicate local cloud distributions near each retrieval and then separate into nearcloud and farfromcloud environments. The comparisons show that low cloud masking is robust, and unscreened thin cirrus would have only a small impact on retrieved AOD. Some of the enhancement is consistent with clearcloud transition zone microphysics such as aerosol swelling. However, 3D radiation interaction between clouds and the surrounding clear air appears to be the primary cause of the high AOD near clouds
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