Global coupled climate models have large long-standing cloud and radiation biases, calling into question their ability to simulate climate and climate change. This study assesses the impact of ...reducing shortwave radiation biases on climate sensitivity within the Community Earth System Model (CESM). The model is modified by increasing supercooled cloud liquid to better match absorbed shortwave radiation observations over the Southern Ocean while tuning to reduce a compensating tropical shortwave bias. With a thermodynamic mixed-layer ocean, equilibrium warming in response to doubled CO
2
increases from 4.1 K in the control to 5.6 K in the modified model. This 1.5 K increase in equilibrium climate sensitivity is caused by changes in two extratropical shortwave cloud feedbacks. First, reduced conversion of cloud ice to liquid at high southern latitudes decreases the magnitude of a negative cloud phase feedback. Second, warming is amplified in the mid-latitudes by a larger positive shortwave cloud feedback. The positive cloud feedback, usually associated with the subtropics, arises when sea surface warming increases the moisture gradient between the boundary layer and free troposphere. The increased moisture gradient enhances the effectiveness of mixing to dry the boundary layer, which decreases cloud amount and optical depth. When a full-depth ocean with dynamics and thermodynamics is included, ocean heat uptake preferentially cools the mid-latitude Southern Ocean, partially inhibiting the positive cloud feedback and slowing warming. Overall, the results highlight strong connections between Southern Ocean mixed-phase cloud partitioning, cloud feedbacks, and ocean heat uptake in a climate forced by greenhouse gas changes.
A
bstract
We investigate the holographic complexity of CFTs compactified on a circle with a Wilson line, dual to magnetized solitons in AdS
4
and AdS
5
. These theories have a ...confinement-deconfinement phase transition as a function of the Wilson line, and the complexity of formation acts as an order parameter for this transition. Through explicit calculation, we show that proposed complexity functionals based on volume and action obey a scaling relation with radius of the circle and further prove that a broad family of potential complexity functionals obeys this scaling behavior. As a result, we conjecture that the scaling law applies to the complexity of conformal field theories on a circle in more general circumstances.
Assessment for Special Education FREY, JENNIFER R.
The Annals of the American Academy of Political and Social Science,
05/2019, Letnik:
683, Številka:
1
Journal Article
Recenzirano
Over the last 40 years, federal legislation has led to improved access to public education for students with disabilities. Today, more than six million students receive special education and related ...services through American public schools; however, evaluation practices for eligibility determination largely have remained unchanged. Assessment approaches used for identification, program planning, and evaluation of progress, arguably, have been insensitive to cultural differences, contributing to disproportional representation of children from different backgrounds in specific special education disability categories, and inefficient because they are too broad to immediately inform instructional planning for both students within and across disability categories. This article critiques current practices for identifying children for special education services and offers considerations, grounded in developmental and cognitive neuroscience, that could lead to more useful assessment approaches that optimize all students’ learning.
A large number of studies have shown a relationship between language disorders and problem behaviors; however, methodological differences have made it difficult to draw conclusions from this ...literature.
To determine the overall impact of language disorders on problem behaviors in children and adolescents between the ages of birth and 18 years and to investigate the role of informant type, age, and type of problem behavior on this relationship.
We searched PubMed, EBSCO, and ProQuest.
Studies were included when a group of children with language disorders was compared with a group of typically developing children by using at least 1 measure of problem behavior.
Effect sizes were derived from all included measures of problem behaviors from each study.
We included 47 articles (63 153 participants). Meta-analysis of these studies revealed a difference in ratings of problem behaviors between children with language disorders and typically developing children of moderate size (
= 0.43; 95% confidence interval 0.34 to 0.53;
< .001). Age was entered as a moderator variable, and results showed that the difference in problem behavior ratings increases with child age (increase in
for each additional year in age = 0.06; 95% confidence interval 0.02 to 0.11;
= .004).
There was considerable heterogeneity in the measures of problem behaviors used across studies.
Children with language disorders display greater rates of problem behaviors compared with their typically developing peers, and this difference is more pronounced in older children.
Background & Aims Direct-acting antiviral agents suppress hepatitis B virus (HBV) load, but they require life-long use. Stimulation of the innate immune system could increase its ability to control ...the virus and have long-lasting effects after a finite regimen. We investigated the effects of immune activation with GS-9620—a potent and selective orally active small molecule agonist of Toll-like receptor 7—in chimpanzees with chronic HBV infection. Methods GS-9620 was administered to chimpanzees every other day (3 times each week) for 4 weeks at 1 mg/kg and, after a 1-week rest, for 4 weeks at 2 mg/kg. We measured viral load in plasma and liver samples, the pharmacokinetics of GS-9620, and the following pharmacodynamics parameters: interferon-stimulated gene expression, cytokine and chemokine levels, lymphocyte and natural killer cell activation, and viral antigen expression. Clinical pathology parameters were monitored to determine the safety and tolerability of GS-9620. Results Short-term oral administration of GS-9620 provided long-term suppression of serum and liver HBV DNA. The mean maximum reduction of viral DNA was 2.2 logs, which occurred within 1 week of the end of GS-9620 administration; reductions of >1 log persisted for months. Serum levels of HBV surface antigen and HBV e antigen, and numbers of HBV antigen–positive hepatocytes, were reduced as hepatocyte apoptosis increased. GS-9620 administration induced production of interferon-α and other cytokines and chemokines, and activated interferon-stimulated genes, natural killer cells, and lymphocyte subsets. Conclusions The small molecule GS-9620 activates Toll-like receptor 7 signaling in immune cells of chimpanzees to induce clearance of HBV-infected cells. This reagent might be developed for treatment of patients with chronic HBV infection.
Summary Infections in critically ill patients are associated with persistently poor clinical outcomes. These patients have severely altered and variable antibiotic pharmacokinetics and are infected ...by less susceptible pathogens. Antibiotic dosing that does not account for these features is likely to result in suboptimum outcomes. In this Review, we explore the challenges related to patients and pathogens that contribute to inadequate antibiotic dosing and discuss how to implement a process for individualised antibiotic therapy that increases the accuracy of dosing and optimises care for critically ill patients. To improve antibiotic dosing, any physiological changes in patients that could alter antibiotic concentrations should first be established; such changes include altered fluid status, changes in serum albumin concentrations and renal and hepatic function, and microvascular failure. Second, antibiotic susceptibility of pathogens should be confirmed with microbiological techniques. Data for bacterial susceptibility could then be combined with measured data for antibiotic concentrations (when available) in clinical dosing software, which uses pharmacokinetic/pharmacodynamic derived models from critically ill patients to predict accurately the dosing needs for individual patients. Individualisation of dosing could optimise antibiotic exposure and maximise effectiveness.
Objectives
The aim of this study was to evaluate different dosage regimens of meropenem in elderly patients in relation with renal function using a population pharmacokinetic (popPK) model.
Methods
...The data of 178 elderly patients treated with meropenem was collected from different sources. A popPK model was developed by using NONMEM® and the influence of different covariates on meropenem CL and V
1
was observed. Monte Carlo dosing simulations were performed at steady state to observe the % T > MIC for targets of 40, 60 and 80% of dosage intervals at different levels of creatinine clearance (CL
CR
).
Results
The data was described by a two-compartment model and the values of parameter estimates for CL, V
1
, Q and V
2
were 5.27 L/h, 17.2 L, 9.92 L/h and 10.6 L, respectively. The CL
CR
, body weight and centre had a significant influence on meropenem CL while no direct influence of age was observed. Extended infusions had pharmacokinetic and pharmacodynamic (PK/PD) breakpoint one dilution greater than corresponding short infusion regimens for each target of % T > MIC.
Conclusion
Meropenem CL was significantly lower in the elderly compared to CL reported in younger patients due to the reduced renal function. An extended infusion of 1000 mg q8h can be considered for empirical treatment of infections in elderly patients when CL
CR
is ≤ 50 mL/min. A continuous infusion of 3000 mg daily dose is preferred if CL
CR
> 50 mL/min. However, a higher daily dose of meropenem would be required for resistant strains (MIC >8 mg/L) of bacteria if CL
CR
is >100 mL/min.
A
bstract
We revisit the study of string theory close to the Hagedorn temperature with the aim towards cosmological applications. We consider interactions of open and closed strings in a gas of D
p
...-branes, and/or one isolated D
p
-brane, in an arbitrary number
d
of flat non-compact dimensions and general compact dimensions. Leading order string perturbation theory is used to obtain the basic interaction rates in a flat background, which are shown to be consistent with the random walk picture of highly excited strings that should apply in more general backgrounds. Using the random walk interpretation we infer the structure of more general semi-inclusive string scattering rates and then write down the corresponding Boltzmann equations describing ensembles of highly excited closed and open strings. We organise the interaction terms in Boltzmann equations so that detailed balance becomes manifest. We obtain the equilibrium solutions and show that they reduce to previously computed solutions for
d
= 0. We further study the behaviour of non-equilibrium fluctuations and find explicit analytic expressions for the equilibration rates (and for the number of open strings in
d
= 0). Potential implications for an early universe with strings at high temperatures are outlined.
A
bstract
We calculate the volume and action forms of holographic complexity for the gravitational collapse of scalar field matter in asymptotically anti-de Sitter spacetime, using numerical methods ...to reproduce the geometry responding to the oscillating field over multiple crossing times. Like the scalar field pulse, the volume complexity oscillates quasiperiodically before horizon formation. It also shows a scaling symmetry with the amplitude of the scalar field. The action complexity is also quasiperiodic with spikes of increasing amplitude.
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