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The complexes of cetyl alcohol, cetomacrogol-1000, and water were successfully synthesized. The complexes were characterized by freeze-drying scanning electron microscopy, small-angle X-ray diffraction (SAXD), and ultra-SAXD. Furthermore, structures, electronic properties (the HOMO-LUMO gap, ionization potential, electron affinity, electronegativity, hardness, softness, dipole moment, and polarizability), and Raman spectra of cetyl alcohol, cetomacrogol-1000, and their binary and ternary complexes with water were also studied using density functional theory. The calculated lengths of hydrophilic heads in the ternary complexes were in good agreement with SAXD data. The results indicated the existence of two types of interlamellar spacings between successive swollen bilayers (approximately 144 and 72 A) when polyoxyethylene groups of cetomacrogol-1000 molecules were completely hydrated and stretched. Besides, in comparison with the monomers, the ternary complex of cetyl alcohol, cetomacrogol-1000, and water with the molecular ratio of 1:1:1 (cetyl-ceto-H2O-1 complex) had outstanding properties.

In this paper, the authors presented some research results on the various surface morphologies of polyaniline (PANi) film, directly synthesised on Pt/SiO2interdigitated microelectrode area by electrochemical method. Theoutcomes of surface morphology and chemical composition structure analysis of PANi film were studied by Field-emission scanning electron microscopy (FE-SEM) and Fourier-transform infrared (FT-IR), respectively. The PANi film was fabricated with the nanowires (NWs) form with their diameter from 50÷100 nm. The length of several micrometers depends on aniline concentration and synthesis condition. The obtained consequences demonstrated that the PANi - NWs are fully potential objects for the detection of NH3gas at room temperature.

In this work, the effects of wood flour and tetraethyl orthosilicate (TEOS) content on the fusion time, fusion torque, fusion temperature, and fusion energy of polyvinyl chloride/wood flour (PVC/WF) composites were studied. Plasma-assisted surface treatment of WF before modifying with TEOS to form the silica nanoparticles on the surface of wood flour plays a role as a reinforcement of the phase interaction. This modification was confirmed by X-ray photoelectron spectroscopy (XPS) and field emission scanning electron microscopy (FESEM) techniques. Moreover, BET data showed that specific surface area and volume of plasma treated WF and TEOS modified WF (WS) were considerably improved in comparison with original WF. By increasing WF, a remarkable increase in time, temperature, and energy of mixing process led to the enhancement of fusion torque. In the case of composite using WS, the increase of TEOS content resulted in shorter fusion time, whereas the other fusion characteristics of composites increased. The investigation of mechanical and rheological properties such as Young’s modulus and dynamic storage modulus G′ showed the stiffness of the PVC/WF composites has been significantly improved with increasing wood flour and modifier contents. The research showed an application of nanoparticles in the industrial production of polymer composite materials.

The structure and stability of ternary systems prepared with polysorbate 60 and various combinations of cetyl (C16) and stearyl (C18) alcohols (fatty alcohol 16g, polysorbate 4g, water 180g) were examined as they aged over 3 months at 25oC. Rheological results showed that the consistency of these systems increased initially during roughly the first week of aging, which was succeeded by little changes in consistency (systems containing from 30% to 70% C18, with the 50% C18 system showing the highest consistencies in viscosity and elasticity) or significant breakdown of structure (remaining systems). The formation and/or disintegration of all ternary systems were also detected by microscopy and differential scanning calorimetry experiments. This study emphasizes the fact that the structure and consistency of ternary systems are dominantly controlled by the swelling capacity of the lamellar $\alpha-$crystalline gel phase. When the conversion of this gel phase into non-swollen $\beta$- or $\gamma$-crystals occurs, systems change from semisolids to fluids. Molecular dynamics simulations were performed to provide important details on the molecular mechanism of our ternary systems. Computational results supported the hypothesis experimentally proposed for the stability of the mixed system being due to an increase in the flexibility, hence an increase in the configurational entropy of the chain tip of the alcohol with a longer hydrocarbon chain (with the highest flexibility observed in the 50:50 C18:C16 system). This finding is in excellent agreement with experimental conclusions. Additionally, simulation data show that in the mixed system, the alcohol with shorter hydrocarbon chain becomes more rigid. These molecular details could not be available in experimental measurements, Comment: 19 ages, 10 figures, 4 tables

Objective: To report an episode of severe diabetic ketoacidosis (DKA) in a type 2 diabetes mellitus (DM) patient with insulin allergy treated by continuous intravenous (IV) regular insulin infusion. Methods: We describe the clinical features, laboratory data, and management of severe DKA in a type 2 DM patient with insulin allergy. Results: A 58-year-old man with type 2 DM initiated subcutaneous insulin administration (SIA) after failure of oral antidiabetic therapies. Symptoms of an allergic reaction then developed, especially distinct at the injection site. Pruritic wheals appeared within 10 minutes of injection and lasted over 24 hours. Both skin prick and intradermal tests were positive with different types of insulin. Two days before admission, he stopped SIA because of allergic symptoms, and then experienced weakness and upper abdominal pain. On admission, his heart rate was 130 beats/min, temperature 37°C, blood pressure 150/90 mmHg, and respiratory rate 28 breaths/min. Blood glucose level was 374.6 mg/dL, pH 6.984, bicarbonate 2.5 mmol/L, lactate 1.5 mmol/L, BUN 24.1 mg/dL, creatinine 1.46 mg/dL, and urinary ketone was 66.48 mg/dL. Over 24 hours, the metabolic acidosis was refractory to IV fluids, bicarbonate and potassium replacement, as well as hemodialysis. Ultimately, he received continuous IV regular insulin infusion at an initial rate of 0.1 units/kg/hour, no further allergic reactions were observed. On the day 5, ketonemia and metabolic acidosis completely resolved. He had transition from IV insulin infusion to SIA on day 14. He was discharged on the day 21 with the treatment of SIA. Three months later, he had a good glycemic control, but has still appeared allergic symptoms at the injection sites of insulin. Conclusion: In this patient, SIA caused an allergic reaction in contrast to continuous IV insulin infusion, for which allergic symptoms did not appear. Thus, identical insulin molecules could behave in markedly different ways depending on the route of injection. Disclosure A.D. Nguyen: None. C.Q. Luong: None. H.C. Chu: None. V.K. Nguyen: None. C.V. Nguyen: None. T.A. Nguyen: None. Q.H. Nguyen: None. T.D. Mai: None. D.V. Nguyen: None. B.Q. Nguyen: None. T.H. Tran: None. N.N. Nguyen: None. S.N. Do: None.

Computer simulations using atomistic model are carried out to investigate the stability of ternary systems of pure or mixed fatty alcohols, cetrimide, and water. These semi−solid oil-in-water systems are used as the main component of pharmaceutical creams. Experiments show that the mixed alcohol systems are more stable than pure ones. The current experimental hypothesis is that this is the result of the length mismatch of the alkyl chains. This leads to higher configurational entropy of the chain tip of the longer alcohol molecules. Our simulation results support this hypothesis. The magnitude in fluctuations in the area per molecule also increases in mixed systems, indicating a higher configurational entropy. Analysis of the molecular structure of simulated systems also shows good agreements with experimental data. Additionally, the results also show that the shorter alcohol molecules become stiffer with higher values of the deuterium order parameters and smaller area per molecule. This leads to more configurational space for the longer alcohol to maximize overall the free energy of the system. This is not known so far in available experimental studies of these systems.

The production dysregulation of reactive oxygen species (ROS) and nitric oxide (NO) in ischemic tissues results in endothelial dysfunction, hyperinflammation and poor blood circulation. Here, we report a hybrid molecule, SA-10 with both NO donating and ROS scavenging abilities that demonstrated potent cytoprotection and tube formation activity in endothelial cells under H2O2-induced oxidative stress. SA-10 loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles (SA-10 NPs) were delivered intramuscularly (IM) to two murine hindlimb ischemia models. In the acute mode ischemia/reperfusion (I/R), the muscle damage, hyperinflammation, and lung edema were significantly reduced 3 days post-dose while in the chronic ischemia model, significant improvement of blood perfusion and physical endurance was observed over 30 days (P

Aim To determine whether home-use icterometry improves parental recognition of neonatal jaundice, early care seeking and treatment to minimize risks of bilirubin encephalopathy. Methods Cluster-randomised controlled trial of community-level icterometry used at home by mothers in Chi Linh, Vietnam. Rural health-care workers identified and enrolled term newborns. Post-partum mothers received jaundice education and icterometry instructions and were cluster-randomised by commune. Cases received icterometers (icterometer group (IG)) and controls did not (control group (CG)). Subjects received mobile telephone calls from post-natal days 2–7 to determine maternal recognition by visual inspection and icterometer detection of jaundice (≥3.0 on five-point scale). Mothers without telephones, premature newborns ( 5 days were excluded. Results Three hundred fifty-two subjects were enrolled (183 IG and 169 CG), of whom 11 (3.4%) were lost to telephone follow-up. Jaundice was recognised and/or detected in 94 (27%) of all newborns. Icterometry helped 11 mothers (6%) detect neonatal jaundice that was not visually recognised by IG mothers. Detection by IG mothers was not statistically greater than CG mothers (P = 0.09). Follow-up care seeking was 8% in both groups (P = 0.2), and 11% of jaundiced newborns received treatment (9% IG vs. 16% CG, P = 0.3). Newborns who received care had bilirubin measurements that averaged 257 μmol/L IG vs. 322 μmol/L CG (P = 0.3). There were no deaths. Conclusions In this pilot study, home-use icterometry may help improve parental detection of jaundice in rural Vietnam. However, larger studies are necessary to determine the changes in recognition, care seeking and treatment.

Estimations of equilibrium or association constant ( K ASSOC ) values reported by many other groups for the supramolecular complexation between [60]fullerene (‘C 60 ’) with different macrocyclic hosts, in solvents such as toluene or carbon disulfide, for example, is often conducted by UV–vis absorption and/or 1 H NMR spectroscopy. In this paper, the complexation behaviour of two calix[4]naphthalene hosts with C 60 in toluene and carbon disulfide has been re-examined, using both of these methods. An analysis is presented of the data newly obtained, in light of recent advances and understanding published by others of the limitations of, in particular, the absorption spectroscopic methods. The discussion presented is also intended to aid those who may be unfamiliar with the nuances and limitations of the analytic models involving C 60 supramolecular complexation. Also presented is a general mechanism for C 60 supramolecular complexation studies, which lay the groundwork for further experiments.

Pentakis(1,4-benzodithiino)corannulene (6) in CS2 formed the strongest 1:1 complexes with C60 and C70 of any corannulene derivative yet reported. The 1,3,5,7,9-pentakis(propylthio)corannulene (4b) formed weaker 1:1 complexes with C60 and C70 in CS2, whereas the decakis(propylthio)corannulene (5b) and unsubstituted corannulene (1) showed no evidence for complexation with either C60 or C70 in CS2.

[picture: see text] The syntheses of the first 2,3-dialkoxy-substituted naphthalene ring-based macrocycles which have calixarene-like structures are reported. The complexation properties of these octahomotetraoxaisocalix[4]naphthalenes were investigated. These new members of the calixnaphthalene family did not demonstrate any appreciable complexation with C(60) or C(70) under the conditions studied, but did so with the tetramethylammonium cation, showing relatively strong association constants suggesting among other considerations that stronger cation-pi interactions versus pi-pi interactions are operative with these hosts. An X-ray crystal structure of the octa-O-ethoxy derivative revealed a structure having a "flattened partial-cone" conformation in which two acetonitrile guest molecules are trapped.

The charge-collection processes of GaAs field-effect transistors are investigated as a function of the incident laser pulse energy via time-resolved charge-collection measurements and by two-dimensional computer simulation. The measurements and simulations reveal a feature that persists on a time scale of 100 ps, the amplitude of which varies strongly with the injected carrier density (pulse energy). The appearance of this feature is associated with a barrier lowering effect at the source/substrate junction, coupled with the drift-assisted transport of electrons through the substrate to the drain contact. This behavior is similar, but not identical to bipolar-gain models that have been suggested previously. We introduce the concept of ion-track segments and illustrate their utility in interrogating the complex mechanisms of charge collection and enhancement in GaAs FETs.

Simultaneous and independent lasing on two different atomic lines is achieved with spatial resolution of laser eigenstates in conjunction with intracavity frequency selection. A sensitivity of 0.3 part in 10(6) meter in the differential detection of methane in 1 atm of air is experimentally demonstrated with this novel dual-wavelength laser. Monitoring the output intensities of the two orthogonally polarized eigenstates permits absolute measurement of methane concentration.

Diatoms are unicellular eukaryotic algae found in fresh and marine water. Each cell is surrounded by an outer shell called a frustule that is composed of highly structured amorphous silica. Diatoms are able to transform silicic acid into these sturdy intricate structures at ambient temperatures and pressures, whereas the chemical synthesis of silica-based materials typically requires extremes of temperature and pH. Cationic polypeptides, termed silica affinity proteins (or silaffins), recently identified from dissolved frustules of specific species of diatoms, are clearly involved and have been shown to initiate the formation of silica in solution. The relationship between the local environment of catalytic sites on these peptides, which can be influenced by the amino acid sequence and the extent of aggregation, and the structure of the silica is not understood. Moreover, the activity of these peptides in promoting silicification at lipid membranes has not yet been clarified. In this work, we developed a model system to address some of these questions. We studied peptide adsorption to Langmuir monolayers and subsequent silicification using X-ray reflectivity and grazing incidence X-ray diffraction. The results demonstrate the lipid affinity of the parent sequence of a silaffin peptide and show that the membrane-bound peptide promotes the formation of an interfacial nanoscale layer of amorphous silica at the lipid-water interface.

The first naphthalene ring-based analogues of the better-known and extensively studied calixarenes were synthesized in 1993. Since that time, our group has focused its research on the design and synthesis of other 'calixnaphthalenes'. These endeavours are motivated partly due to the synthetic challenges which they provide, and to the challenges in deciphering their structural and complexation properties. Calixnaphthalenes offer several advantages over their calixarene analogues. Among these are the facts that they can form deeper, more electron-rich and in some cases, chiral, cavities. They also provide a wide range of potential new scaffolds upon which to design and build new receptors for neutral, or charged guest species. Their supramolecular complexation properties have barely been explored as yet since in most cases, only relatively small quantities only of these compounds have been obtained. In this review, all of the known, and previously unreported calixnaphthalenes are described. As well, some of the compounds, which are described, are still subjects of ongoing research.

Antibody microarrays have the potential to revolutionize protein expression profiling. The intensity of specific signal produced on a feature of such an array is related to the amount of analyte that is captured from the biological mixture by the immobilized antibody (the "capture agent"). This in turn is a function of the surface density and fractional activity of the capture agents. Here we investigate how these two factors are affected by the orientation of the capture agents on the surface. We compare randomly versus specifically oriented capture agents based on both full-sized antibodies and Fab' fragments. Each comparison was performed using three different antibodies and two types of streptavidin-coated monolayer surfaces. The specific orientation of capture agents consistently increases the analyte-binding capacity of the surfaces, with up to 10-fold improvements over surfaces with randomly oriented capture agents. Surface plasmon resonance revealed a dense monolayer of Fab' fragments that are on average 90% active when specifically oriented. Randomly attached Fab's could not be packed at such a high density and generally also had a lower specific activity. These results emphasize the importance of attaching proteins to surfaces such that their binding sites are oriented toward the solution phase.