4,110 research outputs found
A Late Miocene Accipitrid (Aves: Accipitriformes) from Nebraska and Its Implications for the Divergence of Old World Vultures
Background: Old World vultures are likely polyphyletic, representing two subfamilies, the Aegypiinae and Gypaetinae, and some genera of the latter may be of independent origin. Evidence concerning the origin, as well as the timing of the divergence of each subfamily and even genera of the Gypaetinae has been elusive.
Methodology/Principal Findings: Compared with the Old World, the New World has an unexpectedly diverse and rich fossil component of Old World vultures. Here we describe a new accipitriform bird, Anchigyps voorhiesi gen. et sp. nov., from the Ash Hollow Formation (Upper Clarendonian, Late Miocene) of Nebraska. It represents a form close in morphology to the Old World vultures. Characteristics of its wing bones suggest it was less specialized for soaring than modern vultures. It was likely an opportunistic predator or scavenger having a grasping foot and a mandible morphologically similar to modern carrion-feeding birds.
Conclusions/Significance: The new fossil reported here is intermediate in morphology between the bulk of accipitrids and the Old World gypaetine vultures, representing a basal lineage of Accipitridae trending towards the vulturine habit, and of its Late Miocene age suggests the divergence of true gypaetine vultures, may have occurred during or slightly before the Miocene
The Geological Context of Middle Pleistocene Crater Lake Deposits and Fossil Birds at Ulupau Head, Oahu, Hawaiian Islands
Els dipòsits pleistocènics Llacunars del cràter Ulupau, a Oahu, contenen les restes fòssils més antigues d' ocells conegudes a les Illes Hawaïi. Aquests fòssils són importants per documentar les taxes evolutives a una varietat de línies d'ocells terrestres i aquàtics de les illes. Lanàlísí estratigràfic detallat revela diferents cicles deposicionals que comporten dipòsits llacunars interestratificats, colluvium i paleosòls. La conca volcànica va ser oberta per l'erosió marina prèvia al pic del darrer interglacial (estadi isotòpic marí, o 'MIS' Se), fa 125 ka, restringint l'edat dels sediments del Llac al Pleistocè Mitjà. Els tres cicles de deposició (Unitats III, IV i V) semblen estar estretament lligats a pujades interglacials amb una ciclicitat de 100 ka. Donada la complexitat de la successió dels sediments del cràter i el temps requerit per a la seva formació, és probable que la conca deillac s'omplís al Llarg de diferents interglacials, assolint una extensió màxima de més de 50 ha durant l'estadi MIS 11, fa W1S 400 ka. Aquesta és també la màxima edat probable de les capes fossilíferes més riques de la Unitat III, però no es pot excloure que siguin del MIS 9 (fa 300 ka). Els requeriments d'hàbitat probables de diferents elements de l'avifauna donen llum sobre la paleoecologia de la localitat durant el Pleistocè Mitjà.Summary Pleistocene lake deposits in Ulupau Crater on Oahu contain the oldest fossil bird remains known from the Hawaiian Islands. These fossils are important for docwnenting evolutionary rates in a variety of lineages of land and water birds from the islands. Detailed stratigraphic analysis reveals distinct cycles of deposition involving interbedded lacustrine deposits, coLluviwn, and paleosols. The volcanic basin was breached by marine erosion prior to the peak of the last interglaciation (marine isotope stage or 'MIS' Se) over 125 ky ago, constraining the age of the lake sediments to the middle Pleistocene. The three cycles of deposition (Units III, Iv; and V) appear to be closely linked with interglacial highstands with 100 ky cyclicity. Given the complexity of the succession of crater sediments and the time required for their formation, it is probable that the lake basin filled over several interglacials, reaching a maximwn extent of over 50 ha during MIS 11, about 400 ky ago. This is also the likely maximum age of the richest fossil beds in Unit Iv; but MIS 9 (300 ky) also remains a possibility. Probable habitat requirements of the various elements of the avifauna provide insights into the paleoecology of the site during the middle Pleistocene
Stratigraphy and Whole-Rock Amino Acid Geochronology of Key Holocene and Last Interglacial Carbonate Deposits in the Hawaiian Islands
We evaluated the utility of whole-rock amino acid racemization
as a method for the stratigraphic correlation and dating of carbonate sediments
in the Hawaiian Islands. D-alloisoleucine/L-isoleucine (A/I) ratios were determined
for carbonate sand and sandstone samples from 25 localities in the archipelago.
The superposition of A/I ratios within stratigraphic sections and the regional
concordance of ratios within geological formations support the integrity
of the method. To correlate the A/I ratios with an absolute chronology, comparisons
were made with previously published uranium series dates on corals
and with 14C dates on carbonate sand and organic material, including several
new dates reported herein. The A/I mean from four marine isotope stage (MIS)
5e U-series calibration sites was 0.505 ± 0.027 (n = 11), and 12 "test sites" of
previously uncertain or speculative geochronological age yielded an A/I mean
of 0.445 ± 0.058 (n = 17). Similarly, extensive Holocene dunes on Moloka'i
and Kaua'i were correlated by a mean A/I ratio of 0.266 ± 0.022 (n = 8) and
equated with a 14C bulk sediment mean age of 8600 yr B.P. Our results indicate
that the eolian dunes currently exposed in various localities in the Islands originated
primarily during two major periods of dune formation, the last interglacial
(MIS 5e) and the early Holocene (MIS 1). MIS 5e and MIS 1 A/I ratios
from the Hawaiian Islands show close agreement with previous whole-rock
studies in Bermuda and the Bahamas. We discuss these results in terms of their
relevance to models of lithospheric flexure and to imposing constraints on the
time frame for the extinction of fossil birds
Mendelian randomisation identifies priority groups for prophylactic EBV vaccination
BACKGROUND:
Epstein Barr virus (EBV) infects ~ 95% of the population worldwide and is known to cause adverse health outcomes such as Hodgkin’s, non-Hodgkin’s lymphomas, and multiple sclerosis. There is substantial interest and investment in developing infection-preventing vaccines for EBV. To effectively deploy such vaccines, it is vital that we understand the risk factors for infection. Why particular individuals do not become infected is currently unknown. The current literature, describes complex, often conflicting webs of intersecting factors—sociodemographic, clinical, genetic, environmental-, rendering causality difficult to decipher. We aimed to use Mendelian randomization (MR) to overcome the issues posed by confounding and reverse causality to determine the causal risk factors for the acquisition of EBV.
METHODS:
We mapped the complex evidence from the literature prior to this study factors associated with EBV serostatus (as a proxy for infection) into a causal diagram to determine putative risk factors for our study. Using data from the UK Biobank of 8422 individuals genomically deemed to be of white British ancestry between the ages of 40 and 69 at recruitment between the years 2006 and 2010, we performed a genome wide association study (GWAS) of EBV serostatus, followed by a Two Sample MR to determine which putative risk factors were causal.
RESULTS:
Our GWAS identified two novel loci associated with EBV serostatus. In MR analyses, we confirmed shorter time in education, an increase in number of sexual partners, and a lower age of smoking commencement, to be causal risk factors for EBV serostatus.
CONCLUSIONS:
Given the current interest and likelihood of a future EBV vaccine, these factors can inform vaccine development and deployment strategies by completing the puzzle of causality. Knowing these risk factors allows identification of those most likely to acquire EBV, giving insight into what age to vaccinate and who to prioritise when a vaccine is introduced
The Large and Small Scale Structures of Dust in the Star-Forming Perseus Molecular Cloud
We present an analysis of ~3.5 square degrees of submillimetre continuum and
extinction data of the Perseus molecular cloud. We identify 58 clumps in the
submillimetre map and we identify 39 structures (`cores') and 11 associations
of structures (`super cores') in the extinction map. The cumulative mass
distributions of the submillimetre clumps and extinction cores have steep
slopes (alpha ~ 2 and 1.5 - 2 respectively), steeper than the Salpeter IMF
(alpha = 1.35), while the distribution of extinction super cores has a shallow
slope (alpha ~ 1). Most of the submillimetre clumps are well fit by stable
Bonnor-Ebert spheres with 10K < T < 19K and 5.5 < log_10(P_ext/k) < 6.0. The
clumps are found only in the highest column density regions (A_V > 5 - 7 mag),
although Bonnor-Ebert models suggest that we should have been able to detect
them at lower column densities if they exist. These observations provide a
stronger case for an extinction threshold than that found in analysis of less
sensitive observations of the Ophiuchus molecular cloud. The relationship
between submillimetre clumps and their parent extinction core has been
analyzed. The submillimetre clumps tend to lie offset from the larger
extinction peaks, suggesting the clumps formed via an external triggering
event, consistent with previous observations.Comment: 38 pages, 12 figures, accepted by Astrophysical Journal slight
changes to original due to a slight 3" error in the coordinates of the SCUBA
ma
The prevalence of human papillomavirus infections and associated risk factors in men-who-have-sex-with-men in Cape Town, South Africa
Abstract Background We investigated the prevalence of human papillomavirus (HPV) infection and associated behavioural risk factors in men-who-have-sex-with-men (MSM) attending a clinical service in Cape Town, South Africa. Methods MSM were enrolled at the Ivan Toms Centre for Men’s Health in Cape Town. A psychosocial and sexual behavioral risk questionnaire was completed for each participant and urine, oro-pharyngeal and anal swabs were collected for HPV testing using the Linear Array HPV Genotyping Test. Logistic regression analyses were performed to determine sexual risk factors associated with HPV infection at the three anatomical sites. Results The median age of all 200 participants was 32 years (IQR 26-39.5), of which 31.0 % were black, 31.5 % mixed race/coloured and 35.5 % white. The majority of the participants (73.0 %) had completed high school, 42.0 % had a tertiary level qualification and 69.0 % were employed. HPV genotypes were detected in 72.8 % [95 % CI: 65.9–79.0 %], 11.5 % [95 % CI: 7.4–16.8 %] and 15.3 % [95 % CI: 10.5–21.2 %] of anal, oro-pharyngeal and urine specimens, respectively. Prevalence of high-risk (HR)-HPV types was 57.6 % [95 % CI: 50.3–64.7 %] in anal samples, 7.5 % [95 % CI: 4.3–12.1 %] in oro-pharyngeal samples and 7.9 % [95 % CI: 4.5–12.7 %] in urine, with HPV-16 being the most common HR-HPV type detected at all sites. HPV-6/11/16/18 was detected in 40.3 % [95 % CI: 33.3–47.6 %], 4.5 % [95 % CI: 2.1–8.4 %] and 3.2 % [95 % CI: 1.2–6.8 %] of anal, oro-pharyngeal and urine samples, respectively. Multiple HPV types were more common in the anal canal of MSM while single HPV types constituted the majority of HPV infections in the oropharynx and urine. Among the 88 MSM (44.0 %) that were HIV positive, 91.8 % [95 % CI: 83.8–96.6 %] had an anal HPV infection, 81.2 % [95 % CI: 71.2–88.8 %] had anal HR-HPV and 85.9 % [95 % CI: 76.6–92.5 %] had multiple anal HPV types. Having sex with men only, engaging in group sex in lifetime, living with HIV and practising receptive anal intercourse were the only factors independently associated with having any anal HPV infection. Conclusions Anal HPV infections were common among MSM in Cape Town with the highest HPV burden among HIV co-infected MSM, men who have sex with men only and those that practiced receptive anal intercourse. Behavioural intervention strategies and the possible roll-out of HPV vaccines among all boys are urgently needed to address the high prevalence of HPV and HIV co-infections among MSM in South Africa
Nurses\u27 Alumnae Association Bulletin - Volume 6 Number 10
Financial Report
Calendar of Events
Attention, Class of 1945!
Miss Shafer Retires
Review of the Alumnae Association Meetings
Institutional Staff Nurses\u27 Section
Report of Staff Activites - 1948-1949
The Staff
Stockings! Stockings! Stockings!
Pop-Up Toaster
It\u27s Not Too Soon
Any White Elephants?
Private Duty Section
The Jefferson Hospital Private Duty Nurses\u27 Register
Report for Barton Memorial Hospital
Progress of the Orthopedic Department
Just Under the Date Line
Pediatrics at Jefferson
Controlled Respiration in Anesthesia
Anesthesia Progress
Physical Advances at Jefferson During the Past Year
The White Haven Division
The Clara Melville Scholarship Fund
The Relief Fund
The Busy Year for the Nurses\u27 Home Committee of the Women\u27s Board
The Gray Ladies
Memories
Lost
Miscellaneous Items
Medical College News
Marriages
Births
Deaths
Condolences
Prizes
District No. 1 Dues
Help! Help! Help!
Jap Prison School Spurs Nurse to Win University Degree
Twenty Ways to Kill an Organization
The Bulletin Committee
Attention, Alumnae
New Addresse
Recommended from our members
Seafood Certification and Ecolabelling: A New Wrapping on Fisheries Resource Management?
With heightened media attention on the poor state of world fish stocks and the environmental impacts of aquaculture production methods, both governments and seafood industries are keen to demonstrate support for improved management measures. This paper includes results from a DFID funded project concerned with seafood certification, ecolabelling and developing economies. The focus is upon the potential implications of the shift in management power throughout the seafood value chain and the increased reliance upon market-based measures to encourage sustainable production. Certification of fishing and aquaculture operations gives consumers a cue to help distinguish between products on criteria such as sustainability, welfare, health and safety etc. The increased prevalence of certification schemes internationally can be seen as a shift in power, and potentially responsibility, from governments to consumers. It is suggested that this drift may widen as the traditional national regulators lose the power to determine international certification criteria and the public uses purchasing power to determine how their food is produced. Whilst there may be proclaimed benefits of certification and ecolabelling, the paper suggests there could also be adverse consequences for the future development of aquatic food sectors. The advent of certification as a prerequisite for international markets can impose costs, particularly in developing countries without corresponding benefits for all others along the value chain. Mixed fisheries and transboundary stocks present particular challenges to certification, whilst also being more demanding of conventional resource management measures. New species, and those new to markets, where consumers have yet to accurately signal their emergent value may encourage less stringent management measures. Improved understanding of these potential problems is vital if more effective management measures are to be delivered
Nurses\u27 Alumnae Association Bulletin - Volume 7 Number 11
Anna M. Shafer
Barton Memorial Division
Births
Changes in the Ophthalmology Division
Change of Address
Clara Melville Fund
Continental Tour
Deceased
Digest of Meetings
Inter-County Hospitalization Plan
Katherine Childs\u27 Letter
Lost Members
Marriages
Miscellaneous
Nursing Home Committee\u27s Report
Physical Advantages
President James L. Kauffman\u27s Letter
President\u27s Greeting
Private Duty Section
Prizes
Relief Fund
School Nursing
Silhouette of a Public Health Nurse
Rooming-in of Infant with Mother
Staff Activities
The Student
White Haven Divisio
Chemical effects of diceCT staining protocols on fluid-preserved avian specimens
Diffusible iodine-based contrast-enhanced computed tomography (diceCT) techniques allow visualization of soft tissues of fluid-preserved specimens in three dimensions without dissection or histology. Two popular diceCT stains, iodine-potassium iodide (I2KI) dissolved in water and elemental iodine (I2) dissolved in 100% ethanol (EtOH), yield striking results. Despite the widespread use of these stains in clinical and biological fields, the molecular mechanisms that result in color change and radiopacity attributed to iodine staining are poorly understood. Requests to apply these stains to anatomical specimens preserved in natural history museums are increasing, yet curators have little information about the potential for degradation of treated specimens. To assess the molecular effects of iodine staining on typical museum specimens, we compared the two popular stains and two relatively unexplored stains (I2KI in 70% EtOH, I2 in 70% EtOH). House sparrows (Passer domesticus) were collected and preserved under uniform conditions following standard museum protocols, and each was then subjected to one of the stains. Results show that the three ethanol-based stains worked equally well (producing fully stained, life-like, publication quality scans) but in different timeframes (five, six, or eight weeks). The specimen in I2KI in water became degraded in physical condition, including developing flexible, demineralized bones. The ethanol-based methods also resulted in some demineralization but less than the water-based stain. The pH of the water-based stain was notably acidic compared to the water used as solvent in the stain. Our molecular analyses indicate that whereas none of the stains resulted in unacceptable levels of protein degradation, the bones of a specimen stained with I2KI in water demineralized throughout the staining process. We conclude that staining with I2KI or elemental I2 in 70% EtOH can yield high-quality soft-tissue visualization in a timeframe that is similar to that of better-known iodine-based stains, with lower risk of negative impacts on specimen condition
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