scholarly journals Early onset and late acceleration of rapid exhumation in the Namche Barwa syntaxis, eastern Himalaya

Geology ◽  
2020 ◽  
Vol 48 (12) ◽  
pp. 1139-1143
Author(s):  
Gwladys Govin ◽  
Peter van der Beek ◽  
Yani Najman ◽  
Ian Millar ◽  
Lorenzo Gemignani ◽  
...  
Keyword(s):  
Late Miocene ◽  
Late Onset ◽  
Kinematic Model ◽  
Eastern Himalaya ◽  
Published Data ◽  
Surface Erosion ◽  
Crustal Rock ◽  
Capture Event ◽  
Contradictory Evidence ◽  
Namche Barwa

Abstract The Himalayan syntaxes, characterized by extreme rates of rock exhumation co-located with major trans-orogenic rivers, figure prominently in the debate on tectonic versus erosional forcing of exhumation. Both the mechanism and timing of rapid exhumation of the Namche Barwa massif in the eastern syntaxis remain controversial. It has been argued that coupling between crustal rock advection and surface erosion initiated in the late Miocene (8–10 Ma). Recent studies, in contrast, suggest a Quaternary onset of rapid exhumation linked to a purely tectonic mechanism. We report new multisystem detrital thermochronology data from the most proximal Neogene clastic sediments downstream of Namche Barwa and use a thermo-kinematic model constrained by new and published data to explore its exhumation history. Modeling results show that exhumation accelerated to ∼4 km/m.y. at ca. 8 Ma and to ∼9 km/m.y. after ca. 2 Ma. This three-stage history reconciles apparently contradictory evidence for early and late onset of rapid exhumation and suggests efficient coupling between tectonics and erosion since the late Miocene. Quaternary acceleration of exhumation is consistent with river-profile evolution and may be linked to a Quaternary river-capture event.

Denudation of the Namche Barwa antiform, eastern Himalaya

2011 ◽  
Vol 307 (3-4) ◽  
pp. 323-333 ◽  
Author(s):  
E. Enkelmann ◽  
T.A. Ehlers ◽  
P.K. Zeitler ◽  
B. Hallet
Keyword(s):  
Eastern Himalaya ◽  
Namche Barwa

Manic syndromes in old age

2013 ◽  
Author(s):  
Akshya Vasudev
Keyword(s):  
Bipolar Disorder ◽  
Clinical Presentation ◽  
Age Of Onset ◽  
Late Onset ◽  
Epidemiological Data ◽  
The Elderly ◽  
Published Data ◽  
Management Options ◽  
Pharmacological Management ◽  
Heterogenous Group

Manic syndromes in the elderly are different from those seen in the younger bipolar population. They are a heterogenous group but can probably be divided into two main groups based on age of onset of the illness: late onset bipolar disorder (LOB) and early onset bipolar disorder (EOB). This chapter elaborates on differences in these two groups based on epidemiological data findings, clinical presentation, aetiopathogenesis and management. Latest concepts with regards to the vascular mania hypothesis, neuroimaging findings, cognitive impairment in bipolar disorder are also dealt with. A critical review of pharmacological management options is also provided with reference to recently published data on mood stabilisers, antipsychotic and antidepressant usage for this age group.

Vancomycin Prophylaxis for Late-Onset Sepsis in Very Low and Extremely Low Birth Weight Neonates

2008 ◽  
Vol 27 (5) ◽  
pp. 351-354 ◽  
Author(s):  
Susan Givens Bell
Keyword(s):  
Birth Weight ◽  
Low Birth Weight ◽  
Late Onset ◽  
Bloodstream Infections ◽  
Extremely Low Birth Weight ◽  
Causative Organism ◽  
Published Data ◽  
Late Onset Sepsis ◽  
Elbw Neonates ◽  
Central Catheters

LATE-ONSET SEPSIS AMONG very low birth weight (VLBW) and extremely low birth weight (ELBW) neonates is a troubling occurrence. The most recently published data from the National Nosocomial Infection Surveillance system documents 5.4 umbilical- and central line–related bloodstream infections (BSIs) per 1,000 catheter days in infants weighing between 1,001 and 1,500 g.1 For infants weighing 1,000 g or less, the rate is 9.1 infections per 1,000 catheter days. A variety of factors, including prematurity and related relative immunocompromise, altered skin integrity, and multiple invasive procedures, places VLBW and ELBW neonates at risk for infection. Tunneled central catheters or peripherally inserted central catheters (PICCs) clearly add to the risk of infection in these vulnerable patients. In a point prevalence survey of a network of 29 NICUs, researchers found that coagulase-negative Staphylococcus (CoNS) was the causative organism in nearly half (48.3 percent) of the documented bloodstream infections.2 Vancomycin prophylaxis is a potential strategy for the prevention of late-onset sepsis associated with CoNS. This column explores the efficacy and safety of this strategy.

scholarly journals Implications of Hf Isotopes for the Evolution of the Mantle Source of Magmas Associated with the Giant El Teniente Cu-Mo Megabreccia Deposit, Central Chile

2019 ◽  
Author(s):  
Charles R. Stern ◽  
Kwan-Nang Pang ◽  
Hao-Yang Lee ◽  
M. Alexandra Skewes ◽  
Alejandra Arévalo
Keyword(s):  
Late Miocene ◽  
Mantle Source ◽  
Middle Miocene ◽  
Crustal Contamination ◽  
Published Data ◽  
Central Chile ◽  
Subduction Erosion ◽  
Mafic Magmas ◽  
Host Rocks ◽  
El Teniente

We have determined Hf isotopic compositions of 12 samples associated with the giant El Teniente Cu-Mo deposit, Chile. The samples range in age from ≥8.9 to 2.3 Ma and provide information about the temporal evolution of their magmatic sources from the Late Miocene to Pliocene. Together with previously published data, the new analysis indicate a temporal decrease of 10 εHf(t) units, from +11.6 down to +1.6, in the 12.7 m.y. from 15 to 2.3 Ma. These variations imply increasing incorporation of continental crust through time in the magmas that formed these rocks. The fact that the samples include mantle-derived olivine basalts and olivine lamprophyres suggests that these continental components were incorporated into their mantle source, and not by intra-crustal contamination (MASH). We attribute the increase, between the Middle Miocene and Pliocene, of crustal components in the subarc mantle source below El Teniente to be due to increased subduction erosion and transport of crust into the mantle. The deposit formed above a large, long-lived, vertically zoned magma chamber that developed due to compressive deformation and persisted between the period ~7 to 4.6 Ma. Progressively more hydrous mantle-derived mafic magmas feed this chamber from below, providing heat, H2O, S and metals, but no unique “fertile” Cu-rich magma was involved in the formation of the deposit. As the volume of these mantle-derived magmas decreased from the Late Miocene into the Pliocene, the chamber crystallized and solidified, producing felsic plutons and large metal-rich magmatic-hydrothermal breccias that emplaced Cu and S into the older (≥8.9 Ma) mafic host rocks of this megabreccia deposit.

scholarly journals Turtles of the genus Sakya (Geoemydidae): new material from the late Miocene of Russia and Ukraine, new taxonomic diversity and expansion of the stratigraphic range

2015 ◽  
Author(s):  
Elena Syromyatnikova ◽  
Igor Danilov
Keyword(s):  
New Species ◽  
Eastern Europe ◽  
Late Miocene ◽  
Posterior Part ◽  
Detailed Comparison ◽  
Early Pleistocene ◽  
Phylogenetic Position ◽  
Published Data ◽  
Two New Species ◽  
New Material

Background. Sakya Bogachev, 1960 is a genus of geoemydid turtles with unusual scalation of the carapace consisting of 9–10 vertebrals and 8–10 pairs of pleurals. It is known from Neogene localities of Eastern Europe and includes two species: Sakya riabinini (Khosatzky, 1946) (= S. pontica Bogachev, 1960), from the late Miocene (MN13) to early Pleistocene of Eastern Europe (Moldova, Romania, Russia, and Ukraine) and Sakya kolakovskii Chkhikvadze, 1968 from the Pliocene of Abkhazia. Attribution of Melanochelys etuliensis Khosatzky and Redkozubov, 1986 from the early Pliocene of Moldova to Sakya is poorly corroborated. Here we report new material of Sakya from the late Miocene of Russia and Ukraine, which, probably, belongs to one or two new species of this genus and expands its stratigraphic distribution. Methods. We examined new material of Sakya, that includes posterior part of carapace and incomplete plastron from Morskaya 2 locality (MN 13, Rostov Province, Russia), incomplete carapace and plastron from Egorovka locality (MN 12, Odessa Province, Ukraine), and fragmentary shell remains from Fortepianka locality (MN 11, Republic of Adygea, Russia). For comparison we used published data and personal observations on other specimens of Sakya. Results. The specimens from Morskaya 2 and Egorovka are assigned to Sakya based on the presence of increased number of vertebrals and pleurals. Both specimens differ from the described species of Sakya by reduced number of vertebrals (seven in the Morskaya 2 specimen, and five in the Egorovka specimen), and extension of the posteriormost vertebral onto pygal. In addition, they differ from S. riabinini in the presence of eight neurals, longer than wide pleurals, and from S. kolakovskii in the presence of two suprapygals and serrated posterior edge of the carapace. The material from Fortepianka is too fragmentary for detailed comparison, but also differs from S. riabinini in the reduced number of vertebrals. Discussion. The reported material may represent one or two new species of Sakya. The reduced number of vertebrals in these forms probably represents a primitive condition, whereas the extension of the posteriormost vertebral onto the pygal may be a synapomorphy, which unites the new forms. Thus, the Morskaya 2 and Egorovka specimens of Sakya may represent a separate primitive lineage of this genus. In this case, S. kolakovskii and S. riabinini form a more advanced clade with increased number of carapacial scales. These issues as well as phylogenetic position of Sakya within Geoemydidae will be checked by future phylogenetic analysis. The Sakya material from Fortepianka (MN11, late Sarmatian) represents the earliest reliable record of this genus, known previously beginning from MN 12 (Meotic).

scholarly journals Association Study of Clusterin Polymorphism rs11136000 With Late Onset Alzheimer’s Disease in Chinese Han Population

2011 ◽  
Vol 26 (8) ◽  
pp. 627-630 ◽  
Author(s):  
Jian-Fang Ma ◽  
Li-hua Liu ◽  
Yu Zhang ◽  
Ying Wang ◽  
Yu-Lei Deng ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Late Onset ◽  
Meta Analysis ◽  
Recessive Model ◽  
Chinese Han Population ◽  
Published Data ◽  
Chinese Han ◽  
Han Population ◽  
Pcr Rflp

Objective: We conducted a case–control study to investigate whether clusterin polymorphism (rs11136000) was associated with late-onset Alzheimer’s disease in Chinese Han population. Methods: Polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) assay was performed on genotype rs11136000 and APOEε4 in 127 patients with late-onset Alzheimer’s disease and 143 control individuals. Previous published data from other Chinese samples was also included for further meta-analysis. Results: APOEε4 was demonstrated to increase the risk of Alzheimer’s disease in Chinese population (odds ratio = 2.35, 95% confidence interval: 1.40-3.96). There is no significant association between clusterin rs11136000 with late-onset sporadic AD in our small cohort. However, meta-analysis revealed significant allele and genotype differences between Alzheimer’s disease and controls following a recessive model. Conclusion: Clusterin (rs11136000) was associated with Alzheimer’s disease in Chinese Han population.

A Quality Improvement Initiative to Reduce Central Line–Associated Bloodstream Infections in a Neonatal Intensive Care Unit

2010 ◽  
Vol 31 (3) ◽  
pp. 241-248 ◽  
Author(s):  
Matthew J. Bizzarro ◽  
Barbara Sabo ◽  
Melanie Noonan ◽  
Mary-Pat Bonfiglio ◽  
Veronika Northrup ◽  
...  
Keyword(s):  
Intensive Care Unit ◽  
Intensive Care ◽  
Quality Improvement ◽  
Confidence Interval ◽  
Neonatal Intensive Care Unit ◽  
Neonatal Intensive Care ◽  
Late Onset ◽  
Central Line ◽  
Published Data ◽  
Late Onset Sepsis

Objective.To reduce the rate of late-onset sepsis in a neonatal intensive care unit (NICU) by decreasing the rate of central line–associated bloodstream infection (CLABSI).Methods.We conducted a quasi-experimental study of an educational intervention designed to improve the quality of clinical practice in an NICU. Participants included all NICU patients with a central venous catheter (CVC). Data were collected during the period from July 1, 2005, to June 30, 2007, to document existing CLABSI rates and CVC-related practices. A multidisciplinary quality improvement committee was established to review these and published data and to create guidelines for CVC placement and management. Educational efforts were conducted to implement these practices. Postintervention CLABSI rates were collected during the period from January 1, 2008, through March 31, 2009, and compared with preintervention data and with benchmark data from the National Healthcare Safety Network (NHSN).Results.The rate of CLABSI in the NICU decreased from 8.40 to 1.28 cases per 1,000 central line–days (adjusted rate ratio, 0.19 [95% confidence interval, 0.08–0.45]). This rate was lower than the NHSN benchmark rate for level III NICUs. The overall rate of late-onset sepsis was reduced from 5.84 to 1.42 cases per 1,000 patient-days (rate difference, −4.42 cases per 1,000 patient-days [95% confidence interval, −5.55 to −3.30 cases per 1,000 patient-days]).Conclusions.It is possible to reduce the rate of CLABSI, and therefore the rate of late-onset sepsis, by establishing and adhering to evidence-based guidelines. Sustainability depends on continued data surveillance, knowledge of medical and nursing literature, and timely feedback to the staff. The techniques established are applicable to other populations and areas of inpatient care.

scholarly journals Lithologic, tectonic, and climatic controls on chemical weathering, soil production, and erosion in New Zealand

2020 ◽  
Author(s):  
Claire Lukens ◽  
Kevin Norton ◽  
Dennis Dahms ◽  
Eron Raines
Keyword(s):  
Spatial Patterns ◽  
Chemical Weathering ◽  
Large Fraction ◽  
Southern Alps ◽  
Published Data ◽  
Surface Erosion ◽  
Temperature Threshold ◽  
Production Rates ◽  
Erosion Rates ◽  
Soil Production

Over geologic timescales, chemical weathering in mountain landscapes may play an important role in regulating atmospheric CO2. Understanding the feedbacks between climate, tectonics, erosion rates, biota, and weathering has been a recent focus of research, but disentangling these complex relationships remains a challenge. One area of particular interest has been the potential for a kinetic limit to weathering and soil production. Studies in New Zealand's Southern Alps were among the first to clearly exceed proposed kinetic limits on soil production and demonstrate thresholds in the influence of precipitation on chemical weathering. Here we present a new dataset that addresses chemical weathering, soil production rates, and surface erosion rates, measured across an altitudinal transect in the Tararua Range on New Zealand's North Island. The transect spans a kilometer in relief, and receives 3.5-5.5 m of annual precipitation. Underlying bedrock comprises silty and sandy members of the same Cretaceous Greywacke, but subtle lithologic changes correspond to abrupt shifts in soil production rates and total weathering. Total weathering across the transect is roughly invariant for each lithology and reflects near-complete depletion of weatherable species, consistent with a previously proposed threshold in the influence of precipitation. However, spatial patterns in weathering differ markedly in saprolite and in soils. Deep weathering in saprolite decreases with elevation and makes up a large fraction of the total weathering. This pattern suggests that climate may influence saprolite weathering, even where the total weathering is supply-limited. Spatial patterns in saprolite and total weathering do not correlate with an abrupt vegetation transition from dense forest to alpine tussock, which may suggest that biota are more strongly affected by a temperature threshold or more complex biogeochemical cycling. We contrast these results with new and previously published data from the Southern Alps, which have a similar climate but experience rapid tectonic uplift. There, the fresh supply of minerals to soils provided by uplift and erosion may enable much faster weathering and soil production rates. Taken together, these observations suggest a strong lithologic and tectonic control on soil production and weathering rates in humid climates.

scholarly journals Supplemental Material: Enhanced Quaternary exhumation in the Namche Barwa syntaxis, eastern Himalaya

2021 ◽  
Author(s):  
Rong Yang ◽  
et al.
Keyword(s):  
Eastern Himalaya ◽  
Namche Barwa ◽  
Analytical Approaches

Analytical approaches used in this study, analyses parameters, and resulting data.<br>

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