Microfluidic‐Assisted Blade Coating of Compositional Libraries for Combinatorial Applications: The Case of Organic Photovoltaics

Microfluidic technologies are highly adept at generating controllable compositional gradients in fluids, a feature that has accelerated the understanding of the importance of chemical gradients in biological processes. That said, the development of versatile methods to generate controllable compositional gradients in the solid‐state has been far more elusive. The ability to produce such gradients would provide access to extensive compositional libraries, thus enabling the high‐throughput exploration of the parametric landscape of functional solids and devices in a resource‐, time‐, and cost‐efficient manner. Herein, the synergic integration of microfluidic technologies is reported with blade coating to enable the controlled formation of compositional lateral gradients in solution. Subsequently, the transformation of liquid‐based compositional gradients into solid‐state thin films using this method is demonstrated. To demonstrate efficacy of the approach, microfluidic‐assisted blade coating is used to optimize blending ratios in organic solar cells. Importantly, this novel technology can be easily extended to other solution processable systems that require the formation of solid‐state compositional lateral gradients.     

Potential Application of Turnip Oil (Raphanus sativus L.) for Biodiesel Production: Physical–Chemical Properties of Neat Oil, Biofuels and their Blends with Ultra-Low Sulphur Diesel (ULSD)

Turnip oil (TO; Raphanus sativus L.) produces seeds that contain around 26 wt% of inedible base stock that are suitable as a potential feedstock for biodiesel production. A turnip oil methyl ester (TME) was prepared from acid-catalyzed pretreated TO in an effort to evaluate important fuel properties of turnip oil-based biodiesel, such as kinematic viscosity, cloud point, pour point (PP), cold filter plugging point, acid value, oxidative stability and lubricity. A comparison was made with soybean oil methyl esters (SME) as per biodiesel fuel standards such as ASTM D6751 and EN 14214. TME was characterized using FTIR, HPLC and ¹H NMR. Except PP property, SME displays superior fuel properties compared to TME. Blends (B5 and B20) of TME in ultra-low sulphur diesel fuel (ULSD) were also assessed for the aforesaid fuel properties and compared to an analogous set of blends of soybean oil methyl ester in ULSD as per petro diesel fuel standards such as ASTM D975 and D7467. TME B5 blends in ULSD displayed improved PP property in comparison to neat ULSD and blends of SME in ULSD. It was demonstrated that the B5 and B20 blends of TME in ULSD had acceptable fuel properties as per ASTM D975 (for B5 blend) and ASTM D7467 (for B20 blend). In summary, turnip oil has potential as an alternative, non-food feedstock for biodiesel production.     

Molecular modelling and vibrational investigations of ammonium-based ionic liquid (CLTOAB)

CLTOAB is an ammonium-based ionic liquid composed of ε-Caprolactam (CL) C₆H₁₁NO and tetraoctylammonium bromide (TOAB) (C₃₂H₆₈BrN). In this study, experimental IR and Raman spectra of CLTOAB ionic liquid together with the computational results of the compound have been reported. The optimized geometry, vibrational frequencies, IR intensities and Raman activities of the CLTOAB were calculated using the wb97xd and B3LYP density functional methods combined with the 6-31G(d,p) basis set using Gaussian 03 program. The complete assignment of the bands was performed based on the potential energy distributions (PED%). The HOMO and LUMO analysis is used to determine the charge transfer within the molecule. The Gauge-including atomic orbital ¹H-NMR and ¹³C-NMR chemical shifts calculations were carried out and compared with the experimental data. Furthermore to evaluate interaction between CLTOAB and DNA, molecular docking study was carried out.

Communicated by Ramaswamy H. Sarma     

Effect of Iloprost on endothelin-1-induced free radical activation in rabbit brain stem

Iloprost, a stable analogue of prostacyclin, was used to reverse the early period of vasoconstriction provoked by Endothelin-1 by administering into the rabbit basilar artery. We observed if this produced an effect on the central nervous system parenchyma mediated by free radical system. The red neurons were counted in brain stem sections stained with haematoxylin and eosin, while superoxide dismutase and malondialdehyde levels were measured in brain stem tissue samples as a marker of reactive oxygen metabolites; both 30 and 90 min after administration of either Endothelin-1 (0.25 ng) alone or Endothelin-1 followed by Iloprost (0.5 microg/kg) into the basilar artery. Endothelin-1 significantly increased the number of red neurons, while Iloprost significantly reduced them after 30 and 90 min. However, regarding the reactive oxygen metabolites; a similar reversing effect of Iloprost was not observed although superoxide dismutase levels were significantly decreased after Endothelin-1 infusion.     

Endemic goiter, thiocyanate overload, and selenium status in school-age children

Iodine deficiency (ID) and related disorders are still major, yet unresolved health concerns. Recently, in a systematic survey of schoolage children (SAC), we reported severe to moderate ID, in Ankara and three cities from Black Sea region of Turkey. The current study attempted to evaluate selenium (Se) status, thiocyanate (SCN⁻) overload, and their possible contribution to the goiter endemics and thyroid hormone profile observed in these cities. Thyroid ultrasonography was performed and serum Se, SCN⁻, thyroid hormones, sensitive TSH (sTSH) levels, and urinary iodine concentrations (UICs) were determined from 251 SAC (9–11 yr old). Thyroid volumes (TVs) exceeding recommended upper normal limits and median UIC indicated goitre endemics and moderate to severe ID in the areas studied. Mean serum SCN⁻ concentrations were found to be greater than the controls from the literature. The UIC/SCN⁻ ratio was found to be lowest in Bayburt and Trabzon denoting that SCN⁻ overload may contribute to the goiter endemics. Serum Se concentrations represent a marginal deficiency in the four areas studied. No significant correlations between serum Se concentrations and the other parameters studied (i.e., TV, SCN⁻, thyroid hormones, sTSH, UIC) was detected. In conclusion, this study showed that selenium is also marginally deficient in the iodine-deficient endemic areas studied, but this has little or no impact on the thyroid hormone profile and the goiter endemics. SCN⁻ overload may contribute to the endemics, especially for the areas where iodine is severely deficient. An effective iodine supplementation program will not only resolve the goiter endemics but also the consequence of SCN⁻ overload as well in the endemic goiter areas studied.     

Using Adeno-associated Virus as a Tool to Study Retinal Barriers in Disease

Müller cells are the principal glial cells of the retina. Their end-feet form the limits of the retina at the outer and inner limiting membranes (ILM), and in conjunction with astrocytes, pericytes and endothelial cells they establish the blood-retinal barrier (BRB). BRB limits material transport between the bloodstream and the retina while the ILM acts as a basement membrane that defines histologically the border between the retina and the vitreous cavity. Labeling Müller cells is particularly relevant to study the physical state of the retinal barriers, as these cells are an integral part of the BRB and ILM. Both BRB and ILM are frequently altered in retinal disease and are responsible for disease symptoms.There are several well-established methods to study the integrity of the BRB, such as the Evans blue assay or fluorescein angiography. However these methods do not provide information on the extent of BRB permeability to larger molecules, in nanometer range. Furthermore, they do not provide information on the state of other retinal barriers such as the ILM. To study BRB permeability alongside retinal ILM, we used an AAV based method that provides information on permeability of BRB to larger molecules while indicating the state of the ILM and extracellular matrix proteins in disease states. Two AAV variants are useful for such study: AAV5 and ShH10. AAV5 has a natural tropism for photoreceptors but it cannot get across to the outer retina when administered into the vitreous when the ILM is intact (i.e., in wild-type retinas). ShH10 has a strong tropism towards glial cells and will selectively label Müller glia in both healthy and diseased retinas. ShH10 provides more efficient gene delivery in retinas where ILM is compromised. These viral tools coupled with immunohistochemistry and blood-DNA analysis shed light onto the state of retinal barriers in disease.     

Molecular Characterization and Virulence of Beauveria spp. from the Pine Processionary Moth, Thaumetopoea pityocampa (Lepidoptera: Thaumetopoeidae)

The pine processionary moth Thaumetopoea pityocampa (Den. & Schiff.) is one of the most harmful pests to pine species in Mediterranean countries including Turkey. Caterpillars of T. pityocampa are not only significantly harmful to forest trees but also responsible for various allergic reactions in humans and animals. In this study, in order to find a more effective and safe biological control agent against T. pityocampa, we investigated fungal pathogens of T. pityocampa in the Black Sea Region of Turkey and tested their pathogenicity on it. Five different fungi were isolated and identified based on their morphological and molecular characteristics including ITS and partial sequence of EF1-[alpha]. Based on these characteristics, four isolates were identified as Beauveria bassiana cf. Clade C (Rehner and Buckley in Mycologia 97:84–98, 2005) and one isolate was identified as Beauveria bassiana. Among these isolates, B. bassiana KTU-24, B. bassiana cf. Clade C KTU-66 and KTU-67 showed the highest virulence with 100% mortality within 10 days after application. B. bassiana isolate KTU-24 produced the highest mycosis value with %100. Consequently, B. bassiana KTU-24 seems to be good candidate for further investigation as a possible biological control agent against this pest.     

Increase in Candida parapsilosis Fungemia in Critical Care Units: A 6-Years Study

Objectives

We aimed to asses possible clinically significant differences between C. parapsilosis and other candida species candidemia receiving care in the intensive care unit (ICU) setting.

Methods

The study included 118 adult patients diagnosed as candidemia after admission to the ICU of a university hospital between January 2004 and December 2009. Data about demographic characteristics, underlying diseases, and risk factors for ICU-related candidemia were collected.

Results

During the study period, 118 patients with candidemia were identified among 2,853 patients admitted into the ICU. Candidemia was seen in 41.4 cases per 1,000 ICU admissions. The overall incidence of candidemia in ICU patients during the study period was 2.09 per 1,000 hospital admissions. Of the isolates, 18.6% were C. albicans and 81.4% were C. non-albicans. The species most frequently isolated was C. parapsilosis (66.1%, 78/118). The distribution of other Candida spp. was as follows: 15 had C. tropicalis (12.7%) and 3 had C. glabrata (2.5%). By Statistical analysis, when patients with candidemia who had C. parapsilosis were compared with other Candida spp., the following factors were found to be significantly associated with C. parapsilosis fungemia; intravascular catheters (p = 0.008), malignity (p = 0.049) and age (p = 0.039). Relationship was found between C. tropicalis and hematologic malignancies (p = 0.001).

Conclusions

When infections with a high mortality such as candidemia is suspected in critically ill patients, it is important to know local risk factors and epidemiological distributions of causative agents in selection of empirical and effective antifungal treatment.