460 research outputs found
Lifetime corneal edema load model
Purpose: To highlight the potential benefits for long-term use of silicone hydrogels daily disposable (DD) contact lenses, particularly with patients who are noncompliant, sleeping or napping while wearing their lenses, or those who have higher oxygen demands and wear this modality for decades. Methods: Published data for corneal swelling with lenses and no lens wear were used to develop a nonlinear least squares model. The edema load experienced with a range of oxygen transmissibilities (Dk/t) and wear compliance (sleep and napping) was determined. A mixed-effects linear regression model was used to compare the edema load for high and average corneal swellers. Results: The edema load generated demonstrates that a high Dk/t silicone hydrogel lens results in edema levels close to that with no lens wear. In comparison, hydrogels with a Dk/t of 27 (×10−9 [cm mL{O2}][s mLmmHg]), worn on a daily wear schedule will result in 1.5 times more edema and up to two times more if the patient is noncompliant over each decade of wear. High swellers after four decades of wear will have an edema load 10 to 17 times greater than average swellers depending on Dk/t and their degree of noncompliance with the daily wear modality. Conclusions: Prescribing silicone hydrogelDDlenses, particularly with higher DK/t,may help to maintain the long-term ocular health of patients, when they wear their lenses fulltime for many decades. Translational Relevance: Illustrates the importance of Dk/t for any CL wear modality where patients nap or sleep in lenses or have high oxygen needs
Effect of high pressure on multiferroic BiFeO3
We report experimental evidence for pressure instabilities in the model
multiferroic BiFeO3 and namely reveal two structural phase transitions around 3
GPa and 10 GPa by using diffraction and far-infrared spectroscopy at a
synchrotron source. The intermediate phase from 3 to 9 GPa crystallizes in a
monoclinic space group, with octahedra tilts and small cation displacements.
When the pressure is further increased the cation displacements (and thus the
polar character) of BiFeO3 is suppressed above 10 GPa. The above 10 GPa
observed non-polar orthorhombic Pnma structure is in agreement with recent
theoretical ab-initio prediction, while the intermediate monoclinic phase was
not predicted theoretically.Comment: new version, accepted for publication in Phys. Rev.
In vitro mineral nutrition of \u3ci\u3eCurcuma longa\u3c/i\u3e L. affects production of volatile compounds in rhizomes after transfer to the greenhouse
Background
Turmeric is a rich source of bioactive compounds useful in both medicine and cuisine. Mineral concentrations effects (PO43−, Ca2+, Mg2+, and KNO3) were tested during in vitro rhizome development on the ex vitro content of volatile constituents in rhizomes after 6 months in the greenhouse. A response surface method (D-optimal criteria) was repeated in both high and low-input fertilizer treatments. Control plants were grown on Murashige and Skoog (MS) medium, acclimatized in the greenhouse and grown in the field. The volatile constituents were investigated by GC-MS. Results
The total content of volatiles was affected by fertilizer treatments, and in vitro treatment with Ca2+ and KNO3; but PO43− and Mg2+ had no significant effect. The content was higher in the high-input fertilizer treatments (49.7 ± 9 mg/g DM) with 4 mM Ca2+, 60 mM KNO3 and 5 mM NH4+, than the low-input fertilizer (26.6 ± 9 mg/g DM), and the MS control (15.28 ± 2.7 mg/g DM; 3 mM Ca2+, 20 mM K+, 39 mM NO3−, 20 mM NH4+, 1.25 mM PO43−, and 1.5 mM Mg2+). The interaction of Ca2+ with KNO3affected curcumenol isomer I and II, germacrone, isocurcumenol, and β-elemenone content. Increasing in vitro phosphate concentration to 6.25 mM increased ex vitro neocurdione and methenolone contents. Conclusion
These results show that minerals in the in vitro bioreactor medium during rhizome development affected biosynthesis of turmeric volatile components after transfer to the greenhouse six months later. The multi-factor design identified 1) nutrient regulation of specific components within unique phytochemical profile for Curcuma longa L. clone 35–1 and 2) the varied phytochemical profiles were maintained with integrity during the greenhouse growth in high fertility conditions
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Advancing Pharmacist Collaborative Care within Academic Health Systems.
INTRODUCTION:The scope of pharmacy practice has evolved over the last few decades to focus on the optimization of medication therapy. Despite this positive impact, the lack of reimbursement remains a significant barrier to the implementation of innovative pharmacist practice models. SUMMARY:We describe the successful development, implementation and outcomes of three types of pharmacist collaborative care models: (1) a pharmacist with physician oversight, (2) pharmacist-interprofessional teams and (3) physician-pharmacist teams. The outcome measurement of these pharmacist care models varied from the design phase to patient volume measurement and to comprehensive quality dashboards. All of these practice models have been successfully funded by affiliated health systems or grants. CONCLUSIONS:The expansion of pharmacist services delivered by clinical faculty has several benefits to affiliated health systems: (1) significant improvements in patient care quality, (2) access to experts in specialty areas, and (3) the dissemination of outcomes with national and international recognition, increasing the visibility of the health system
Ekonomik Büyüme ile Borsa Performansı Arasındaki İlişki: Türkiye Üzerine Ampirik Bir Araştırma1 The Relationship Between Economic Growth and Stock Market Performance: An Empirical Research on Turkey
Gelişmekte olan ülkelerde ekonomide meydana gelen gelişmelere bağlı olarak,
borsa performansı ve ekonomik büyüme ilişkisi araştırmacıların ilgisini çeken bir
konudur. Ancak literatür incelendiğinde konuya ilişkin elde edilen sonuçların ülkeden
ülkeye farklılık göstermesi nedeni ile bu ilişki hakkında literatürde bir fikir birliği
bulunmamaktadır. Bu araştırmanın amacı; Türkiye için ekonomik büyüme ile borsa
performansı arasındaki ilişkiyi belirlemektir. Çalışmada öncelikle ekonomik büyüme ve
borsa performansı arasındaki ilişki tanıtılacaktır. Çalışma konuya ilişkin literatür
taraması ile devam edecektir. Son olarak ise 2000 - 2017 dönemini kapsayan ampirik
araştırma ile çalışma sonlandırılacaktır. İlgili dönemde Granger nedensellik testi
sonucunda ekonomik büyüme ile borsa performansı arasında anlamlı bir ilişki tespit
edilememiştir.
Depending on the economic developments, the relationship between stock market
performance and economic growth is a matter of interest to researchers in the
developing countries. But when the literature is examined, there isn’t a consensus about
this relationship in the literature by reason of the fact that the subject differ from
country to country. The purpose of the study is to determine the relationship between
economic growth and stock market performance for Turkey. In the study first of all, the
relationship between economic growth and stock market performance will be
introduced and the study will continue with literature review. Finally, the study will be
ended with empirical analysis which includes 2000-2017 period. A significant
relationship could not be determined in the related period according to the result of
Granger Causality Test
An in vitro study on the combination effect of metformin and N-Acetyl cysteine against hyperglycaemia-Induced cardiac damage
Chronic hyperglycaemia is a major risk factor for diabetes-induced cardiovascular dysfunction. In a hyperglycaemic state, excess production of reactive oxygen species (ROS), coupled with decreased levels of glutathione, contribute to increased lipid peroxidation and subsequent myocardial apoptosis. N-acetylcysteine (NAC) is a thiol-containing antioxidant known to protect against hyperglycaemic-induced oxidative stress by promoting the production of glutathione. While the role of NAC against oxidative stress-related cardiac dysfunction has been documented, to date data is lacking on its beneficial effect when used with glucose lowering therapies, such as metformin (MET). Thus, the aim of the study was to better understand the cardioprotective effect of NAC plus MET against hyperglycaemia-induced cardiac damage in an H9c2 cardiomyoblast model. H9c2 cardiomyoblasts were exposed to chronic high glucose concentrations for 24 h. Thereafter, cells were treated with MET, NAC or a combination of MET and NAC for an additional 24 h. The combination treatment mitigated high glucose-induced oxidative stress by improving metabolic activity i.e. ATP activity, glucose uptake (GU) and reducing lipid accumulation. The combination treatment was as effective as MET in diminishing oxidative stress, lipid peroxidation and apoptosis. We observed that the combination treatment prevented hyperglycaemic-induced cardiac damage by increasing GLUT4 expression and mitigating lipid accumulation via phosphorylation of both AMPK and AKT, while decreasing nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB), as well as protein kinase C (PKC), a known activator of insulin receptor substrate-1 (IRS-1), via phosphorylation at Ser307. On this basis, the current results support the notion that the combination of NAC and MET can shield the diabetic heart against impaired glucose utilization and therefore its long-term protective effect warrants further investigation
Scanning tunneling microscopy and Raman spectroscopy of polymeric sp-sp2 carbon atomic wires synthesized on the Au(111) surface
Long linear carbon nanostructures based on sp-hybridization can be synthesized by exploiting on-surface synthesis of halogenated precursors evaporated on Au(111), thus opening a way to investigations by surface-science techniques. By means of an experimental approach combining scanning tunneling microscopy and spectroscopy (STM and STS) with ex situ Raman spectroscopy we investigate the structural, electronic and vibrational properties of polymeric sp-sp2 carbon atomic wires composed by sp-carbon chains connected through phenyl groups. Density-functional-theory (DFT) calculations of the structure and the electronic density of states allow us to simulate STM images and to compute Raman spectra. The comparison of experimental data with DFT simulations unveil the properties and the formation stages as a function of the annealing temperature. Atomic-scale structural information from STM complement the Raman sensitivity to the single molecular bond to open the way to detailed understanding of these novel carbon nanostructures
Razrada popisa kriterija za odabir 3D virtualnih svjetova i izradu obrazovnog okruženja
The purpose of this study was to develop a criteria list to be considered during the selection of 3D virtual world platforms for educational purposes. As the first step in this process a draft list was created by the researchers based on literature review and heuristic investigation. The draft list was reviewed and revised by 2 internal and 4 external experts, and then used as a questionnaire. The items in the finalized criteria list were divided into three categories as follows: 50 items of technical specifications (system/program features, usability, software tools, multimedia tools, security, and cost), 21 items of interaction specifications (avatars, activities, communication tools) and 8 items of educational specifications (teaching/learning activities). Ultimately, the developed criteria list will be helpful for identifying and eliminating the deficiencies and constraints of virtual worlds used for educational purposes.Svrha ovog istraživanja bila je razrada popisa kriterija koje treba uzeti u obzir prilikom odabira 3D virtualnih platformi u obrazovne svrhe. U tom su procesu znanstvenici najprije sastavili nacrt kriterija na osnovi proučene literature i heurističkog istraživanja. Dva naša i četiri vanjska stručnjaka pregledala su i napisala osvrt na nacrt kriterija koji se zatim koristio u obliku upitnika. Završni popis kriterija podijeljen je u sljedeće tri kategorije: 50 tehničkih kriterija (osobine sustava / programa, iskoristivost, softverski alati, multimedijski alati, sigurnost, cijena), 21 kriterij vezan uz interakciju (avatari, aktivnosti, komunikacijski alati) i 8 obrazovnih kriterija (aktivnosti poučavanja / učenja). Na kraju će razrađeni popis kriterija pomoći u utvrđivanju i uklanjanju nedostataka i ograničenja virtualnih svjetova koji se koriste u obrazovne svrhe
Preparation of acid-responsive antibubbles from CaCO3-based Pickering emulsions.
HYPOTHESIS: Hydrophobized fumed silica particles were previously reported for producing antibubbles that are quite stable in neutral as well as in acidic media. To produce acid-responsive antibubbles (e.g., for gastric drug delivery), the silica nanoparticles must be replaced by suitable particles, e.g., calcium carbonate (CaCO 3), which can degrade at low pH to release the encapsulated drug. EXPERIMENTS: Two variants of CaCO 3-stabilized antibubbles were prepared (by using CaCO 3 particles pre-coated with stearic acid, or by using native CaCO 3 particles in combination with sodium stearoyl lactylate) and drug release was compared with classic antibubbles produced with hydrophobized fumed silica particles. FINDINGS: CaCO 3 particles (pre-coated with stearic acid) can be used to produce stable antibubbles, which provided an entrapment efficiency of a model drug (methylene blue, MB) of around 85%. A burst release of MB (∼60%) from the antibubbles was observed at pH 2 (i.e., the pH of the stomach), which was further increased to 80% during the next 30 min. On the contrary, at neutral pH, about 70% of the drug remained encapsulated for at least 2 h. We further demonstrated that the acidic conditions led to the desorption of CaCO 3 particles from the air-liquid interface resulting in the destabilization of the antibubbles and the release of drug-containing cores
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