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A new physical scheme is presented for the detection of copper, based on the use of a fluorescently labeled dendrimer anchored on a gold nanowire. Upon light illumination surface plasmon resonance was generated from the gold nanowire, which promoted quenching of the dendrimer fluorescence as a result of the energy transfer between the dendrimer and the copper ions. The monotonic dependence of the fluorescence quenching on copper concentration was exploited to reach a copper detection sensitivity of 2 nM. In addition, the fluorescence of the labeled dendrimers was quenched specifically by copper in a matrix of common metal ions. Using simulations we calculated the enhanced optical near field for a dendrimer-coated gold nanowire illuminated by a TM-polarized plane wave, which provided a physical basis for the sensitive copper detection using the current experimental scheme. [ABSTRACT FROM AUTHOR]

A 41-year-old African male presented with worsening dyspnea and cachexia concerning for congestive heart failure. Transesophageal echocardiogram revealed a large mass attached to the aortic valve leaflet, mass attached to the flail anterior mitral valve leaflet, severe pulmonary hypertension and dilatation of the aortic root along with fistula between the right coronary aortic cusp and the right ventricular (RV) outflow tract. Blood cultures grew Abiotrophia Defectiva (AD) sensitive to vancomycin. Patient underwent emergent surgical closure of aorto RV fistula and aortic root replacement along with pulmonary and mitral valve replacement. Endocarditis caused by AD has been reported to result in heart failure, septic embolization and destruction of the valve despite use of appropriate antibiotics. To our knowledge, this is the only case of AD endocarditis without any identified entrance route; requiring replacement of pulmonary, mitral and aortic valve due to extensive valvular damage and large vegetations. [ABSTRACT FROM AUTHOR]

In an effort to find correlations between size changes with temperature of lipophilic polymers in solution and viscosity index trends, the determination of the size of thermoresponsive polymers of various architectures (linear, comb-like, star, and hyperbranched) using two experimental techniques under infinite dilution conditions (0.5% w/w) â€" dynamic light scattering and small angle neutron scattering, and predictive molecular dynamics simulations is described herein. Viscosity index is an important parameter for lubricants and other rheological applications. The aim of this work was to predict polymer behavior as viscosity index improvers (VIIs) using tools which require minimal amounts of material, as opposed to measuring kinematic viscosities, which require multigram quantities. There were no significant correlations between changes in polymer size with temperature and viscosity index (VI). The polymers with the highest VI (polyalkyl methacrylate - PAMA and Star PAMA) had polar backbones in contrast to the nonpolar backbones of the linear and hyperbranched (OCP and HBPE, respectively), so the disparity in solubility of the backbone and solvent medium appears to correlate with the observed VIs. It was concluded that none of the aforementioned techniques can entirely predict the polymer behavior as VIIs, at least in the temperature range studied (40â€"100 °C). [ABSTRACT FROM AUTHOR]

Dendrimer-encapsulated ruthenium oxide nanoparticles (DEN-RuO2) have been used as catalysts in lithium-oxygen (Li-O2) batteries for the first time. The results obtained from ultraviolet-visible spectroscopy, electron microscopy and X-ray photoelectron spectroscopy show that the nanoparticles synthesized by the dendrimer template method are ruthenium oxide, not metallic ruthenium as reported by other groups. The DEN-RuO2 significantly improves the cycling stability of Li-O2 batteries with carbon electrodes and decreases the charging potential even at ten times less catalyst loading than those reported previously. The monodispersity, porosity, and large number of surface functionalities of the dendrimer template prevent the aggregation of the RuO2 nanoparticles, making their entire surface area available for catalysis. The potential of using DEN-RuO2 as a standalone cathode material for Li-O2 batteries is also explored. [ABSTRACT FROM AUTHOR]

Bio-oil is a promising alternative source of energy produced from fast pyrolysis of biomass. Increasing the viscosity of bio-oil during storage is a major problem that can be controlled by the addition of methanol or other alcohols. This paper reports the results of our investigation of the reactions of short chain alcohols with aldehydes and acids in bio-oil. The reaction of methanol with hydroxyacetaldehyde (HA) to form the acetal was catalyzed by the addition of 7 x 10-4 M strong acids such as sulfuric, hydrochloric, p-toluene sulfonic acid, and methanesulfonic acid. HA formed 2,2-dimethoxyethanol (DME), and at 60 °C the equilibrium was reached in less than one hour. Smaller amounts of DME were formed in the absence of strong acid. HA, acetaldehyde, and propanal formed their corresponding acetals when reacted with methanol, ethanol, 1- propanol or 1-butanol. Esters of acetic acid and hydroxyacetic acid were observed from reactions with these same four alcohols. Other acetals and esters were observed by GC/MS analysis of the reaction products. The results from accelerated aging experiments at 90 °C suggest that the presence of methanol slows polymerization by formation of acetals and esters from low molecular weight aldehydes and organic acids. [ABSTRACT FROM AUTHOR]

Abstract: Previous studies observed that slow copyrolysis of wood and plastic in enclosed autoclaves produced an upgraded raw bio-oil with increased hydrogen content. We now demonstrate that fast simultaneous pyrolyses of 50:50, w/w, pine wood/waste plastics in a 2kg/h lab scale auger-fed reactor at 1atm, with a short vapor residence time, generates higher heating value upgraded bio-oils. Three plastics: polystyrene (PS), high density polyethylene (HDPE) and polypropylene (PP) were individually copyrolyzed with southern yellow pine wood at 525, 450 and 450°C, respectively, to generate modified bio-oils upon condensation. These liquids exhibited higher carbon and hydrogen contents, significantly lower oxygen contents, higher heats of combustion and lower water contents, acid values and viscosities than pine bio-oil. The formation of cross-over wood/plastic reaction products was negligible in the oils. Simultaneous pyrolysis process design requires using a temperature at which the plastic’s thermal decomposition kinetics produce vapors rapidly enough to prevent vaporized plastic from condensing on wood chars and exiting the reactor. [Copyright &y& Elsevier]

Rechargeable lithium (Li) metal batteries with conventional LiPF 6 -carbonate electrolytes have been reported to fail quickly at charging current densities of about 1.0 mA cm −2 and above. In this work, we demonstrate the rapid charging capability of Li||LiNi 0.8 Co 0.15 Al 0.05 O 2 (NCA) cells can be enabled by a dual-salt electrolyte of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and lithium bis(oxalato)borate (LiBOB) in a carbonate solvent mixture. The cells using the LiTFSI-LiBOB dual-salt electrolyte significantly outperform those using the LiPF 6 electrolyte at high charging current densities. At the charging current density of 1.50 mA cm −2 , the Li||NCA cells with the dual-salt electrolyte can still deliver a discharge capacity of 131 mAh g −1 and a capacity retention of 80% after 100 cycles. The Li||NCA cells with the LiPF 6 electrolyte start to show fast capacity fading after the 30th cycle and only exhibit a low capacity of 25 mAh g −1 and a low retention of 15% after 100 cycles. The reasons for the good chargeability and cycling stability of the cells using the LiTFSI-LiBOB dual-salt electrolyte can be attributed to the good film-formation ability of the electrolyte on the Li metal anode and the highly conductive nature of the sulfur-rich interphase layer. [ABSTRACT FROM AUTHOR]

Implementation of nanotechnology in agriculture is intimately dependent on the capacity of nanoparticles (NPs) to move within the plant body and reach the targeted cells. Although the fibrillar nature of the plant cell wall permits the movement of molecules through its porous matrix (apoplast), the movement of particles through the aqueous apoplastic milieu has its size limitations given the tightly knitted cellulose/ hemicellulose fiber structure. In the present study, we used fluorescent NPs of different composition and sizes, and followed their movement into citrus leaves by fluorescent microscopy. Our results indicate that in citrus leaves, the size exclusion limit for NPs is of ≈5.4 nm. This conclusion was based on the capacity ofPAMAM dendrimers G-4 and G-5 (4.5 and 5.4 nm, respectively) to move through the cell wall and into the phloem, but failure of similar PAMAM dendrimers G-6 (6.7 nm) to move through the apoplast. Dendrimer NPs 5.4 nm and smaller were observed to penetrate the leaf tissue, and then taken up and mobilized by the phloem elements. The current study provides evidence on the size limit for NPs use in agriculture. [ABSTRACT FROM AUTHOR]

We present results from experiments and atomistic molecular dynamics simulations on the remediation of naphthalene by polyamidoamine (PAMAM) dendrimers and graphene oxide (GrO). Specifically, we investigate 3rd-6th generation (G3-G6) PAMAM dendrimers and GrO with different levels of oxidation. The work is motivated by the potential applications of these emerging nanomaterials in removing polycyclic aromatic hydrocarbon contaminants from water. Our experimental results indicate that GrO outperforms dendrimers in removing naphthalene from water. Molecular dynamics simulations suggest that the prominent factors driving naphthalene association to these seemingly disparate materials are similar. Interestingly, we find that cooperative interactions between the naphthalene molecules play a significant role in enhancing their association to the dendrimers and GrO. Our findings highlight that while selection of appropriate materials is important, the interactions between the contaminants themselves can also be important in governing the effectiveness of a given material. The combined use of experiments and molecular dynamics simulations allows us to comment on the possible factors resulting in better performance of GrO in removing polyaromatic contaminants from water. [ABSTRACT FROM AUTHOR]

Background: Better risk stratification strategies are needed to enhance clinical care and trial design in heart failure with preserved ejection fraction (HFpEF).Objectives: The purpose of this study was to assess the value of a targeted plasma multi-marker approach to enhance our phenotypic characterization and risk prediction in HFpEF.Methods: In this study, the authors measured 49 plasma biomarkers from TOPCAT (Treatment of Preserved Cardiac Function Heart Failure With an Aldosterone Antagonist) trial participants (n = 379) using a Multiplex assay. The relationship between biomarkers and the risk of all-cause death or heart failure-related hospital admission (DHFA) was assessed. A tree-based pipeline optimizer platform was used to generate a multimarker predictive model for DHFA. We validated the model in an independent cohort of HFpEF patients enrolled in the PHFS (Penn Heart Failure Study) (n = 156).Results: Two large, tightly related dominant biomarker clusters were found, which included biomarkers of fibrosis/tissue remodeling, inflammation, renal injury/dysfunction, and liver fibrosis. Other clusters were composed of neurohormonal regulators of mineral metabolism, intermediary metabolism, and biomarkers of myocardial injury. Multiple biomarkers predicted incident DHFA, including 2 biomarkers related to mineral metabolism/calcification (fibroblast growth factor-23 and OPG [osteoprotegerin]), 3 inflammatory biomarkers (tumor necrosis factor-alpha, sTNFRI [soluble tumor necrosis factor-receptor I], and interleukin-6), YKL-40 (related to liver injury and inflammation), 2 biomarkers related to intermediary metabolism and adipocyte biology (fatty acid binding protein-4 and growth differentiation factor-15), angiopoietin-2 (related to angiogenesis), matrix metalloproteinase-7 (related to extracellular matrix turnover), ST-2, and N-terminal pro-B-type natriuretic peptide. A machine-learning-derived model using a combination of biomarkers was strongly predictive of the risk of DHFA (standardized hazard ratio: 2.85; 95% confidence interval: 2.03 to 4.02; p < 0.0001) and markedly improved the risk prediction when added to the MAGGIC (Meta-Analysis Global Group in Chronic Heart Failure Risk Score) risk score. In an independent cohort (PHFS), the model strongly predicted the risk of DHFA (standardized hazard ratio: 2.74; 95% confidence interval: 1.93 to 3.90; p < 0.0001), which was also independent of the MAGGIC risk score.Conclusions: Various novel circulating biomarkers in key pathophysiological domains are predictive of outcomes in HFpEF, and a multimarker approach coupled with machine-learning represents a promising strategy for enhancing risk stratification in HFpEF. [ABSTRACT FROM AUTHOR]

With the significant progress made in the development of cathodes in lithium-sulfur (Li-S) batteries, the stability of Li metal anodes becomes a more urgent challenge in these batteries. Here the systematic investigation of the stability of the anode/electrolyte interface in Li-S batteries with concentrated electrolytes containing various lithium salts is reported. It is found that Li-S batteries using LiTFSI-based electrolytes are more stable than those using LiFSI-based electrolytes. The decreased stability is because the N-S bond in the FSI− anion is fairly weak and the scission of this bond leads to the formation of lithium sulfate (LiSOx) in the presence of polysulfide species. In contrast, in the LiTFSI-based electrolyte, the lithium metal anode tends to react with polysulfide to form lithium sulfide (LiSx), which is more reversible than LiSOx formed in the LiFSI-based electrolyte. This fundamental difference in the bond strength of the salt anions in the presence of polysulfide species leads to a large difference in the stability of the anode-electrolyte interface and performance of the Li-S batteries with electrolytes composed of these salts. Therefore, anion selection is one of the key parameters in the search for new electrolytes for stable operation of Li-S batteries. [ABSTRACT FROM AUTHOR]

Lithium-sulfur (Li-S) redox flow battery (RFB) is a promising candidate for high energy large-scale energy storage application due to good solubility of long-chain polysulfide species and low cost of sulfur. Here, the fundamental understanding and control of lithium polysulfide chemistry are studied to enable the development of liquid phase Li-S redox flow prototype cells. These differ significantly from conventional static Li-S batteries targeting for vehicle electrification. A high solubility of the different lithium polysulfides generated at different depths of discharge and states of charge is required for a flow battery in order to take full advantage of the multiple electron transitions. A new dimethyl sulfoxide based electrolyte is proposed for Li-S RFBs, which not only enables the high solubility of lithium polysulfide species, especially for the short-chain species, but also results in excellent cycling with a high Coulombic efficiency. The challenges and opportunities for the Li-S redox flow concept have also been discussed in depth. [ABSTRACT FROM AUTHOR]

In recent years, the Li metal anode has regained a position of paramount research interest because of the necessity for employing Li metal in next-generation battery technologies such as Li-S and Li-O2. Severely limiting this utilization, however, are the rapid capacity degradation and safety issues associated with rechargeable Li metal anodes. A fundamental understanding of the failure mechanism of Li metal at high charge rates has remained elusive due to the complicated interfacial chemistry that occurs between Li metal and liquid electrolytes. Here, it is demonstrated that at high current density the quick formation of a highly resistive solid electrolyte interphase (SEI) entangled with Li metal, which grows towards the bulk Li, dramatically increases up the cell impedance and this is the actual origin of the onset of cell degradation and failure. This is instead of dendritic or mossy Li growing outwards from the metal surface towards/through the separator and/or the consumption of the Li and electrolyte through side reactions. Interphase, in this context, refers to a substantive layer rather than a thin interfacial layer. Discerning the mechanisms and consequences for this interphase formation is crucial for resolving the stability and safety issues associated with Li metal anodes. [ABSTRACT FROM AUTHOR]

Suppressing lithium (Li) dendritegrowth is one of the most critical challenges for the developmentof Li metal batteries. Here, we report for the first time the growthof dendrite-free lithium films with a self-aligned and highly compactednanorod structure when the film was deposited in the electrolyte consistingof 1.0 M LiPF6in propylene carbonate with 0.05 M CsPF6as an additive. Evolution of both the surface and the cross-sectionalmorphologies of the Li films during repeated Li deposition/strippingprocesses were systematically investigated. It is found that the formationof the compact Li nanorod structure is preceded by a solid electrolyteinterphase (SEI) layer formed on the surface of the substrate. Electrochemicalanalysis indicates that an initial reduction process occurred at ∼2.05V vs Li/Li+before Li deposition is responsible for theformation of the initial SEI, while the X-ray photoelectron spectroscopyindicates that the presence of CsPF6additive can largelyenhance the formation of LiF in this initial SEI. Hence, the smoothLi deposition in Cs+-containing electrolyte is the resultof a synergistic effect of Cs+additive and preformed SEIlayer. A fundamental understanding on the composition, internal structure,and evolution of Li metal films may lead to new approaches to stabilizethe long-term cycling stability of Li metal and other metal anodesfor energy storage applications. [ABSTRACT FROM AUTHOR]

Background: Thyroid storm (TS) is a rare life-threatening condition that is characterized by fever and altered mental status precipitated by endogenous or exogenous critical events, illness/injury, acute iodine load, and thyroid or non thyroid surgery. A large number of thyroid extracts are available and extensively used, even though they are not recommended clinically in hypothyroid or euthyroid patients. Consumption of such products can be dangerous and result in life-threatening TS. Here, we report a case of TS caused by inadvertent intake of very high dosages of triiodothyronine (T3) and thyroxine (T4) in compounded thyroid extracts. Plasmapheresis may be considered an option for the management of exogenous TS. Patient Findings: A 62-year-old woman with no significant past medical history presented with severe myalgia, fever, tachycardia, and blood pressure of 170/80 mmHg, which precipitated to an altered mental state within 24 hours. Neurological examination did not reveal any focal deficit or any signs of meningeal irritation. Further investigation revealed that she had been taking thyroid supplements. The patient had accidentally been supplied with a batch of thyroid extract pills that had an inadvertently high content of T4. Her free T3 (FT3) and free T4 (FT4) levels were found to be very high beyond the laboratory readable range (FT3>30 pg/mL; FT4>6.06 ng/dL; thyrotropin [TSH]=0.07 IU/mL). Summary: Three days post commencement of standard conservative management of TS, the patient developed posterior reversible encephalopathy syndrome, resulting in a seizure. She remained unresponsive and in a poor mental state. The confirmed exogenous etiology for TS led to a decision to conduct plasmapheresis. Plasmapheresis conducted for two consecutive days proved successful as a therapeutic measure for TS and improved her thyroid profile as well as her mental state. Conclusions: The inappropriate use of thyroid extracts in euthyroid and hypothyroid patients can result in life-threatening TS. Plasmapheresis is probably a life-saving treatment in patients who are exposed to amounts of thyroid hormone far in excess of that usually produced by the thyroid gland. [ABSTRACT FROM AUTHOR]

The physical interaction between a lipid vesicle and a silver nanoparticle (AgNP)-human serum albumin (HSA) protein 'corona' has been examined. Specifically, the binding of AgNPs and HSA was analyzed by spectrophotometry, and the induced conformational changes of the HSA were inferred from circular dichroism spectroscopy. The fluidity of the vesicle, a model system for mimicking cell membrane, was found to increase with the increased exposure to AgNP-HSA corona, though less pronounced compared to that induced by AgNPs alone. This study offers additional information for understanding the role of physical forces in nanoparticle-cell interaction and has implications for nanomedicine and nanotoxicology. [ABSTRACT FROM AUTHOR]

Examines the identification of a neuronal binding partner of gigaxonin. Characteristics of the giant axonal neuropathy; Importance of gigaxonin for neuronal survival; Insights on the pathogenesis of neurodegenerative disorders related to cytoskeletal abnormalities.

Introduction: Accurate diagnosis of pulmonary hypertension (PH) is made using invasive right heart catheterization (RHC). Prior studies have shown the utility of imaging techniques like computerized tomography (CT) as alternatives to predict PH. Hypothesis: To determine the predictive ability of CT measured main pulmonary artery diameter (PA) to aortic diameter (AO) ratio in identifying PH. Methods: A retrospective observational study conducted in 211 consecutive patients who had RHC and CT chest within 6 months of each other between the years 2012-2015. Two expert radiologists measured main PA diameter at the bifurcation and AO diameter from the same CT image. Furthermore, we conducted a sub-group analysis to see if the ratio performs better in assessing PH in chronic kidney disease patients. Linear correlation and logistic regression analysis was used to examine the association between PA:AO ratio by CT scan with invasive hemodynamics. Receiver operator characteristic analysis was used to evaluate the ability of using PA:AO ratio to predict PH. Resting PH was defined as mean pulmonary artery pressure of ≥25 mmHg. CKD was defined as GFR between 15- 60 mL/min/ 1.73 m2 and no indication for dialysis. Results: Mean time between CT and RHC 3 days with minimum of 5.06 months (-152 days) to 5.56 months (167 days). Intraclass correlation coefficient between the two radiologists was 0.86 (95% CI of 0.75-0.92) with a P <0.01. CT measured PA:AO is highly correlated with mPAP after adjustment of age, race and gender (r=0.37, P <0.001). In a multivariate logistic model, every 0.15 U (1±SD) increase in PA:AO ratio was associated with 2.99 times higher (95% CI 1.99-4.49, P <0.01) odds of having PH , while in CKD subgroup, every 0.15 U (1±SD) increase in PA:AO ratio was associated with 11.9 times higher odds of having PH (95% CI 2.10-67.6, P =0.005), adjusting for age, race and gender. Conclusion: CT derived PA:AO ratio is predictive of PH. [ABSTRACT FROM AUTHOR]