334 research outputs found
Onset and Evolution of Southern Annular Mode-Like Changes at Centennial Timescale
The Southern Westerly Winds (SWW) are the surface expression of geostrophic winds that encircle the southern mid-latitudes. In conjunction with the Southern Ocean, they establish a coupled system that not only controls climate in the southern third of the world, but is also closely connected to the position of the Intertropical Convergence Zone and CO2 degassing from the deep ocean. Paradoxically, little is known about their behavior since the last ice age and relationships with mid-latitude glacier history and tropical climate variability. Here we present a lake sediment record from Chilean Patagonia (51°S) that reveals fluctuations of the low-level SWW at mid-latitudes, including strong westerlies during the Antarctic Cold Reversal, anomalously low intensity during the early Holocene, which was unfavorable for glacier growth, and strong SWW since âź7.5 ka. We detect nine positive Southern Annular Mode-like events at centennial timescale since âź5.8 ka that alternate with cold/wet intervals favorable for glacier expansions (Neoglaciations) in southern Patagonia. The correspondence of key features of mid-latitude atmospheric circulation with shifts in tropical climate since âź10 ka suggests that coherent climatic shifts in these regions have driven climate change in vast sectors of the Southern Hemisphere at centennial and millennial timescales.Fil: Moreno, P.I.. Universidad de Chile; ChileFil: Vilanova, Isabel. Consejo Nacional de Investigaciones CientĂficas y TĂŠcnicas. Oficina de CoordinaciĂłn Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales âBernardino Rivadaviaâ; ArgentinaFil: Villa-MartĂnez, R.. Universidad de Magallanes; ChileFil: Dunbar, R.B.. University of Stanford; Estados UnidosFil: Mucciarone, D.A.. University of Stanford; Estados UnidosFil: Kaplan, M.R.. Columbia University; Estados UnidosFil: Garreaud, R.D.. Universidad de Chile; ChileFil: Rojas, M.. Universidad de Chile; ChileFil: Moy, C.M.. University of Otago; Nueva ZelandaFil: De Pol-Holz, R.. Universidad de Magallanes; ChileFil: Lambert, F.. Pontificia Universidad CatĂłlica de Chile; Chil
Mapping cell-in-cell structures in oral squamous cell carcinoma
Cell-in-cell (CIC) structures contribute to tumor aggressiveness and poor prognosis in
oral squamous cell carcinoma (OSCC). In vitro 3D models may contribute to the understanding of
the underlying molecular mechanisms of these events. We employed a spheroid model to study
the CIC structures in OSCC. Spheroids were obtained from OSCC (HSC3) and cancer-associated
fibroblast (CAF) lines using the Nanoshuttle-PLTM bioprinting system (Greiner Bio-One). Spheroid
form, size, and reproducibility were evaluated over time (EvosTM XL; ImageJ version 1.8). Slides
were assembled, stained (hematoxylin and eosin), and scanned (Axio Imager Z2/VSLIDE) using
the OlyVIA System (Olympus Life Science) and ImageJ software (NIH) for cellular morphology and
tumor zone formation (hypoxia and/or proliferative zones) analysis. CIC occurrence, complexity, and
morphology were assessed considering the spheroid regions. Well-formed spheroids were observed
within 6 h of incubation, showing the morphological aspects of the tumor microenvironment, such
as hypoxic (core) and proliferative zone (periphery) formation. CIC structures were found in both
homotypic and heterotypic groups, predominantly in the proliferative zone of the mixed HSC3/CAF
spheroids. âComplex cannibalismâ events were also noted. These results showcase the potential of
this model in further studies on CIC morphology, formation, and relationship with tumor prognosis
On the Origin of the Outgoing Black Hole Modes
The question of how to account for the outgoing black hole modes without
drawing upon a transplanckian reservoir at the horizon is addressed. It is
argued that the outgoing modes must arise via conversion from ingoing modes. It
is further argued that the back-reaction must be included to avoid the
conclusion that particle creation cannot occur in a strictly stationary
background. The process of ``mode conversion" is known in plasma physics by
this name and in condensed matter physics as ``Andreev reflection" or ``branch
conversion". It is illustrated here in a linear Lorentz non-invariant model
introduced by Unruh. The role of interactions and a physical short distance
cutoff is then examined in the sonic black hole formed with Helium-II.Comment: 12 pages, plain latex, 2 figures included using psfig; Analogy to
``Andreev reflection" in superfluid systems noted, references and
acknowledgment added, format changed to shorten tex
Correlations of structural, magnetic, and dielectric properties of undoped and doped CaCu3Ti4O12
The present work reports synthesis, as well as a detailed and careful
characterization of structural, magnetic, and dielectric properties of
differently tempered undoped and doped CaCu3Ti4O12 (CCTO) ceramics. For this
purpose, neutron and x-ray powder diffraction, SQUID measurements, and
dielectric spectroscopy have been performed. Mn-, Fe-, and Ni-doped CCTO
ceramics were investigated in great detail to document the influence of
low-level doping with 3d metals on the antiferromagnetic structure and
dielectric properties. In the light of possible magnetoelectric coupling in
these doped ceramics, the dielectric measurements were also carried out in
external magnetic fields up to 7 T, showing a minor but significant dependence
of the dielectric constant on the applied magnetic field. Undoped CCTO is
well-known for its colossal dielectric constant in a broad frequency and
temperature range. With the present extended characterization of doped as well
as undoped CCTO, we want to address the question why doping with only 1% Mn or
0.5% Fe decreases the room-temperature dielectric constant of CCTO by a factor
of ~100 with a concomitant reduction of the conductivity, whereas 0.5% Ni
doping changes the dielectric properties only slightly. In addition,
diffraction experiments and magnetic investigations were undertaken to check
for possible correlations of the magnitude of the colossal dielectric constants
with structural details or with magnetic properties like the magnetic ordering,
the Curie-Weiss temperatures, or the paramagnetic moment. It is revealed, that
while the magnetic ordering temperature and the effective moment of all
investigated CCTO ceramics are rather similar, there is a dramatic influence of
doping and tempering time on the Curie-Weiss constant.Comment: 10 pages, 11 figure
Ăndice de recuperação e qualidade de ovĂłcitos de bezerras Nelore, superovuladas e nĂŁo superovuladas, de dois a trĂŞs meses de idade
Pain and quality of life among older people with rheumatoid arthritis and/or osteoarthritis: a literature review
Burden and risk factors for Pseudomonas aeruginosa community-acquired pneumonia:a Multinational Point Prevalence Study of Hospitalised Patients
Pseudornonas aeruginosa is a challenging bacterium to treat due to its intrinsic resistance to the antibiotics used most frequently in patients with community-acquired pneumonia (CAP). Data about the global burden and risk factors associated with P. aeruginosa-CAP are limited. We assessed the multinational burden and specific risk factors associated with P. aeruginosa-CAP.
We enrolled 3193 patients in 54 countries with confirmed diagnosis of CAP who underwent microbiological testing at admission. Prevalence was calculated according to the identification of P. aeruginosa. Logistic regression analysis was used to identify risk factors for antibiotic-susceptible and antibiotic-resistant P. aeruginosa-CAP.
The prevalence of P. aeruginosa and antibiotic-resistant P. aeruginosa-CAP was 4.2% and 2.0%, respectively. The rate of P. aeruginosa CAP in patients with prior infection/colonisation due to P. aeruginosa and at least one of the three independently associated chronic lung diseases (i.e. tracheostomy, bronchiectasis and/or very severe chronic obstructive pulmonary disease) was 67%. In contrast, the rate of P. aeruginosa-CAP was 2% in patients without prior P. aeruginosa infection/colonisation and none of the selected chronic lung diseases. The multinational prevalence of P. aeruginosa-CAP is low.
The risk factors identified in this study may guide healthcare professionals in deciding empirical antibiotic coverage for CAP patients
Track D Social Science, Human Rights and Political Science
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138414/1/jia218442.pd
Intrapopulational genetic differentiation in Anopheles (N.) darlingi Root, 1926 (Diptera: Culicidae) in the amazon region
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