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Nucleic acids (NAs) in modern biology accomplish a variety of tasks, and the emergence of primitive nucleic acids is broadly recognized as a crucial step for the emergence of life. While modern NAs have been optimized by evolution to accomplish various biological functions, such as catalysis or transmission of genetic information, primitive NAs could have emerged and been selected based on more rudimental chemical–physical properties, such as their propensity to self-assemble into supramolecular structures. One such supramolecular structure available to primitive NAs are liquid crystal (LC) phases, which are the outcome of the collective behavior of short DNA or RNA oligomers or monomers that self-assemble into linear aggregates by combinations of pairing and stacking. Formation of NA LCs could have provided many essential advantages for a primitive evolving system, including the selection of potential genetic polymers based on structure, protection by compartmentalization, elongation, and recombination by enhanced abiotic ligation. Here, we review recent studies on NA LC assembly, structure, and functions with potential prebiotic relevance. Finally, we discuss environmental or geological conditions on early Earth that could have promoted (or inhibited) primitive NA LC formation and highlight future investigation axes essential to further understanding of how LCs could have contributed to the emergence of life.

Cancer-associated fibroblasts (CAF) are highly prevalent cells in the tumor microenvironment in clear cell renal cell carcinoma (ccRCC). CAFs exhibit a pro-tumor effect in vitro and have been implicated in tumor cell proliferation, metastasis, and treatment resistance. Our objective is to analyze the geospatial distribution of CAFs with proliferating and apoptotic tumor cells in the ccRCC tumor microenvironment and determine associations with survival and systemic treatment. Pre-treatment primary tumor samples were collected from 96 patients with metastatic ccRCC. Three adjacent slices were obtained from 2 tumor-core regions of interest (ROI) per patient, and immunohistochemistry (IHC) staining was performed for αSMA, Ki-67, and caspase-3 to detect CAFs, proliferating cells, and apoptotic cells, respectively. H-scores and cellular density were generated for each marker. ROIs were aligned, and spatial point patterns were generated, which were then used to perform spatial analyses using a normalized Ripley’s K function at a radius of 25 μm (nK(25)). The survival analyses used an optimal cut-point method, maximizing the log-rank statistic, to stratify the IHC-derived metrics into high and low groups. Multivariable Cox regression analyses were performed accounting for age and International Metastatic RCC Database Consortium (IMDC) risk category. Survival outcomes included overall survival (OS) from the date of diagnosis, OS from the date of immunotherapy initiation (OS-IT), and OS from the date of targeted therapy initiation (OS-TT). Therapy resistance was defined as progression-free survival (PFS) &lt, 6 months, and therapy response was defined as PFS &gt, 9 months. CAFs exhibited higher cellular clustering with Ki-67+ cells than with caspase-3+ cells (nK(25): Ki-67 1.19, caspase-3 1.05, p = 0.04). The median nearest neighbor (NN) distance from CAFs to Ki-67+ cells was shorter compared to caspase-3+ cells (15 μm vs. 37 μm, respectively, p &lt, 0.001). Multivariable Cox regression analyses demonstrated that both high Ki-67+ density and H-score were associated with worse OS, OS-IT, and OS-TT. Regarding αSMA+CAFs, only a high H-score was associated with worse OS, OS-IT, and OS-TT. For caspase-3+, high H-score and density were associated with worse OS and OS-TT. Patients whose tumors were resistant to targeted therapy (TT) had higher Ki-67 density and H-scores than those who had TT responses. Overall, this ex vivo geospatial analysis of CAF distribution suggests that close proximity clustering of tumor cells and CAFs potentiates tumor cell proliferation, resulting in worse OS and resistance to TT in metastatic ccRCC.

The solution stability of the active materials poly(3-hexylthiophene) (P3HT), [6,6]-phenyl C61 butyric acid methyl ester (PCBM), and P3HT:PCBM blends were studied by a combination of organic photovoltaic (OPV) device performance, ultraviolet–visible (uv–vis) spectroscopy, and simulation calculations. OPV devices based on the structure ITO/PEDOT:PSS/Active layer (P3HT:PCBM)/Al showed that pure P3HT, pure PCBM, and P3HT:PCBM blend solutions could be stable for as long as one month when stored in either a glovebox or in air. Especially, P3HT:PCBM solution blends are much more stable than P3HT or PCBM solutions stored separately, in which the former could be stored stably over two months. The addition of PCBM to P3HT solution forms P3HT:PCBM dimers, avoiding the formation of charge transfer complexes. The calculation results showed that the electronic wave-function of highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) are isolated in P3HT:PCBM dimers. The research provides a new understanding on the stability of P3HT and P3HT:PCBM solutions, and has great practical application in the fabrication of large-area OPV modules by printing or coating techniques.

Large-area, flexible organic photovoltaic (OPV) modules are fabricated successfully by gravure printing in air, using an industrial-scale printing proofer of similar performance to commercial roll-to-roll printing processes. Both the hole transport layer, poly-3,4-ethylenedioxy-thiophene:poly(styrene sulfonic-acid) (PEDOT:PSS), and the active layer, poly(3-hexylthiophene):[6,6]-phenyl C61 butyric acid methyl ester (P3HT:PCBM), are successively printed on indium tin oxide (ITO) coated polyethylene terephthalate (ITO/PET) substrates with evaporated aluminum (Al) top electrodes. The 45 cm 2 modules, composed of 5 cells connected in series, show power conversion efficiency (PCE) of over 1.0%, in which the short-circuit current ( J sc ) and open-circuit voltage ( V oc ) are as high as 7.14 mA/cm 2 and 2.74 V (0.55 V per cell), respectively. The PCEs could be potentially improved by the further optimization of the layer interface, layer morphology and flexible substrate properties. The results suggest that gravure printing may be a suitable technique for fast commercial processing of large-area, flexible OPVs with high output.

a b s t r a c t The performance of a flexible, thin-film, zinc-air battery can be improved significantly if using a sodium silicate as a novel inorganic binder pigment for the anode components. Formulations consisting of zinc and carbon in sodium silicate are applied onto various substrates (glass or indium tin oxide) by casting and printing methods. Film properties such as mechanical stability, surface resistivity, surface conductivity, surface morphology, thickness and the metal content were correlated to the composition of the films. Prototype batteries were prepared by connecting those anodes to poly(3,4-ethylenedioxythiophene)- based air cathode and the electrochemical conversion efficiencies were determined in 1 mol/dm3 sodium chloride and basic 8 mol/dm

In this paper, we report our ongoing investigations into the properties of poly(vinyl)chloride (PVC) based polymeric membranes incorporating the ionic liquid (IL) trihexyltetradecylphosphonium dicyanamide [P6,6,6,14][DCA] which fulfils several key functions - plasticiser, ligand and transducer dye. Upon co-ordination with Cu2+ ions, a yellow colour is generated within the membrane. Similarly exposure of a membrane to Co2+ ions produces a blue colour, whilst the IL is capable of co-ordinating both ions simultaneously, thereby generating a green optical response. Using Wireless Radio Frequency (WRF) detection however, the inherent conducting nature of these membranes can now also be exploited as a sensor signal. WRF is a novel detection technique which monitors the conductivity of a given sample wirelessly, allowing non-contact detection and measurement of IL-PVC membranes as they pass through the channel. The various co-ordinated membranes produce a discriminatory drop in the resulting signal, which is a direct function of the specific metal ion (Cu2+, Co2+ or a mixture) co-ordinated to the IL. The results of the novel WRF technique have been validated principally by electrochemical impedance spectroscopy (EIS) and also by portable x-ray fluorescence (XRF). Keywords: Ionic Liquids, Electrochemical Sensors, Polymeric Sensors

Low-MW urethanes were investigated to control domain formation as well as inhibiting cleavage reactions during vapor phase polymerization of PEDOT. A diurethanediol (DUDO) was identified as a highly efficient mediator for the process, resulting in PEDOT films exceeding conductivities of 1 000 S · cm−1. All the urethanes investigated had the desired inhibiting effect on the polymerization, but all apart from DUDO also introduced unwanted domain formation on the micrometer scale. The addition of PEG generally improved conductivity by suppressing the domain formation and, with an optimized combination of DUDO and PEG, conductivities over 1 200 S · cm−1 were achieved.

Water-soluble-doped ZnS quantum dots were synthesised and formulated for inkjet printing. The quantum dots were then inkjet-printed onto a variety of substrates, including photo quality inkjet paper, cotton fabric, PET film, and glass. Of these substrates, only inkjet printing of doped ZnS quantum dots on photo-quality inkjet paper and cotton fabric produced a photoluminescent print. The materials were characterised using a number of methods, including profilometer measurements, photoluminescence spectroscopy (PL), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and viscosity measurements. On excitation with UV light, a photoluminescence emission of approximately 600 nm was observed.

A novel system for the detection of ammonia was developed by monitoring the conductance of inkjet printed or screen printed polyaniline films with a radio frequency detector. The system has the advantage of non-contact detection of ammonia within sealed packages. Since the sensor is a passive printed film that is externally interrogated, it does not require an internal power source or associated circuitry, and therefore may be a low-cost device suitable for smart packaging applications. When printed on a suitable substrate, the sensor can be cycled several times using heat or a volatile acid to regenerate the polyaniline surface.

A series of iron(III) alkylbenzenesulfonate (ABS) salts were prepared by the reaction of ferric hydroxide, Fe(OH)3·xH2O, with a variety of aromatic sulfonic acids. The products were characterised by microanalysis and FTIR spectroscopy. The microanalysis data generated indicated that three of the salts were not mononuclear iron(III) compounds and were of the formula [(OH2)5Fe–O–Fe(OH2)5][C2H5C6H4SO3]4, [(OH2)5Fe–O–Fe(OH2)5][CH3C6H4SO3]4·2H2O and [(OH2)5Fe–O–Fe(OH2)5][CH3C6H4SO3]4. Some degree of condensation or cross-linking of Fe(III) centres into hydrolytic oligomers had occurred. The X-ray crystal structure of the Fe(III) toluenesulfonate salt established the formula of an oxo-centred, binuclear complex [(H2O)5Fe(μ-O)Fe(OH2)5]4+. Vapour phase polymerisation (VPP) of pyrrole monomer was carried out using iron(III) benzenesulfonate, p-ethylbenzenesulfonate, dodecylbenzenesulfonate and p-toluenesulfonate. As the chain length of the Fe(III) alkylbenzenesulfonates increased it was found that the film forming ability of the polypyrrole was enhanced, probably as a result of a decrease in polymer chain interaction resulting from increased free volume between polymer chains. Variations in the conductivity of the polypyrrole films was observed when Fe(III) p-toluenesulfonate salts obtained from different sources (two commercial samples and one synthesised in our laboratories) were used as the oxidant. Films deposited using these oxidants generally exhibited higher conductivity than those formed using the Fe(III) p-ethylbenzenesulfonate and Fe(III) p-dodecylbenzenesulfonate salts.

The hydroxytriarylmethane family of dyes (sub-category sulfonphthaleins, e.g. phenol red) has shown sufficient chemical stability to remain unchanged when exposed to the oxidative environment required for chemical polymerisation of inherently conducting polymers (ICPs). This oxidative stability allows these dyes to be incorporated as counter-ions in polypyrrole or poly(3,4-ethylenedioxythiophene), and then later released when the ICP is reduced, either by change in potential or change in pH. The polypyrrole–dye composite can be applied to paper or plastic films by inkjet printing a dye–oxidant mixture which is then dried and used as a template for vapour phase polymerisation. For poly(3,4-ethylenedioxythiophene)–dye composites, polymerisation can be conveniently conducted in a single step in the liquid phase, using a volatile organic base as a retardant during application.

A highly conducting stretchable polymer material has been patterned using additive inkjet printing and by subtractive agarose stamping of a deactivation agent (hypochlorite). The material consisted of elastomeric polyurethane combined in an interpenetrating network with a conductive polymer, poly(3,4-ethylenedioxythiophene) (PEDOT). The agarose stamping produced 50 μm wide conducting lines with high spatial fidelity. The deactivation agent was found to cause some degradation of the remaining conducting lines, as revealed by a stronger increase in resistance upon straining compared to the pristine polymer material. Inkjet printing of the material was only possible if a short-chain polyurethane was used as elastomer to overcome strain hardening at the neck of the droplets produced for printing. Reproducible line widths down to 200 μm could be achieved by inkjet printing. Both methods were used to fabricate test patterns that allowed the electrical resistance parallel and perpendicular to the elongation direction to be measured. Electrical resistance increased both parallel and perpendicular to the direction of strain, with a faster increase observed parallel to the straining.

Conducting polymers such as polypyrrole may be useful in smart packaging products, provided application methods can be developed that circumvent the insolubility and infusibility of these materials. Experiments were conducted in five research areas relevant to the application of polypyrrole to nonrigid substrates. The studies reveal that application of polypyrrole from the liquid phase, either by deposition from depleted bulk solution or inkjet printing dispersions, is unlikely to give films as regular as those produced by vapor phase polymerization. Using the latter approach, two potential methods of applying patterned polypyrrole films to nonrigid substrates were developed. The first used hypochlorite to pattern a continuous film of polypyrrole, previously applied by vapor phase polymerization. The second used inkjet printing to apply an oxidant solution, whose pH had been raised with a volatile base, to nonrigid substrates. The higher pH reduced corrosion of the print head, increasing the lifetime of printers exposed to oxidative compounds. The base was subsequently evaporated by heating, and the dried oxidant used as a template for vapor phase polymerization of polypyrrole. This method gave smooth, shiny and adherent polypyrrole films on papers and polyester transparency, with high resolution. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 3938–3947, 2007

The expression of cholecystokinin 2 receptor (CCK2R, CCKBR or gastrin receptor) has been reported on a diverse range of cancers such as colorectal, liver, lung, pancreatic, ovarian, stomach, thyroid and numerous neuroendocrine/carcinoid tumors. Some cancers of the colorectum, lung, pancreas and thyroid have been shown to overexpress CCK2R in relation to normal matched tissues of the same organ. This reported overexpression has led to the development of a number of CCK2R-ligand targeted imaging and therapeutic agents. However, no comprehensive study comparing the expression of CCK2R in multiple cancers to multiple normal tissues has been performed. Herein, we report the immunohistochemical analysis of cancer samples from gastrointestinal stromal tumor (GIST), hepatocellular carcinoma (HCC), non-small cell lung cancer (NSCLC), pancreatic adenocarcinoma, and thyroid cancer against multiple normal tissue samples from esophagus, liver, lung, pancreas, stomach, spleen and thyroid. These results show that CCK2R expression is present in nearly all cancer and normal samples tested and that none of the cancer samples had expression that was statistically greater than that of all of the normal samples.

For approximately 30 yr, laboratories studying dental and bone diseases such as osteoporosis, osteomalacia, or orthopedic implant devices have used fluorochrome labels to measure the mineral apposition rate. Fixation of the bone with 10% neutral buffered formalin has been routinely used by many of these laboratories. Routine custom has been to fix the bone specimens in formalin for no more than 48 hr, wash them in water, and place them in 40–70% ethanol for further fixation and/or storage. This paper reports a study that demonstrates fixation of bones for up to 90 days in 10% neutral buffered formalin caused no evident loss of the fluorochrome labels. (The J Histotechnol 21:299–302, 1998)

Laboratory technicians have been preparing bone samples for fluorochrome viewing since the late 1950s. Improvements in technique and advancements in materials have enabled specimen processing and preparation to elevate to a higher standard of quality. However, there is no set of standards with which to guide the novice in preparing slides for subsequent microscopic observation. This study reports results from 15 slide comparison methods. While many of the slide preparation techniques yielded similar results to the control slide, several methods including three staining procedures, were substandard for optimal fluorochrome viewing. (The J Histotechnol 25:103, 2002)Submitted March 15, 2002; accepted April 5, 2002

Laboratories investigating dental and bone diseases or orthopedic implant devices have used fluorochrome labels to quantify bone growth for over 40 years. Bone fixation with 10% neutral buffered formalin has been used by many of these laboratories. Routine practice has been to fix the bone samples in formalin for no more than 48 hr, wash them in water, and place the specimens in 40–70% ethanol for further fixation and/or storage. This paper reports a study that builds on a previous investigation and demonstrates fixation of bones for up to 1 yr in 10% neutral buffered formalin caused no evident loss of fluorochrome labels. However, the study also demonstrates that fixation in Safefix® at 1 yr caused mixed results. Although most of the 1 yr slides exhibited no apparent fading of the fluorochromes, there were two slides that did have fading of the labels. (The J Histotechnol 25:99, 2002)Submitted March 15, 2002; accepted April 5, 2002

DOI: 10.1002/aenm.201401539 materials than are commonly used in research labs. We have used an industrial printer to produce BHJ solar cells [ 12 ] and found that over 30 L of ink was required to start roll-to-roll production. On a smaller scale, an industrial proofer, which is used to mimic printing conditions in a roll-to-roll production line, still consumed a lot of ink, with 100 mL of ink and 3 g of polymer typically used in a single set of experiments. [ 12 ] Even a small, laboratory scale, roll-to-roll printer typically requires a few tens of milliliters of ink. Although most of the ink used to fi ll the reservoir can often be recovered, the amount of material required to test various formulations is far more than typically available for newly synthesized materials. Therefore, very few results for fully printed solar cells have been reported with high performance materials. The convergence of BHJ, DSSC, and perovskite device structures provides the fi eld with an opportunity to now focus on the “lab-to-fab” translation of these solar cell technologies. To do this, ready access to a coating process that enables the solution-based deposition of multiple layers is required. In the general area of rapid prototyping, 3D printing has emerged as a powerful tool for the low-cost, rapid production of industrial products or prototypes. [ 13 ] 3D Printing is an example of additive manufacturing that builds a device from a surface, directly from a design meaning that a computer-aided design (CAD) fi le can be transformed to a fi nished product without additional cutting or assembling steps. Among the many types of 3D printers that are available, the fused deposition modeling (FDM) type printer has been developed rapidly and is becoming more and more popular as it becomes more affordable. FDM 3D printers have been developed to produce objects by printing multiple thick layers (typically over 100 μm) of melted plastic but can also be used to produce thin, solid fi lms. FDM 3D printers are technically an automated extruder with x, y, z position control and typically can vary head speed/acceleration/ deceleration as well as the temperature of the nozzles and a printing bed. Resources to build and control FDM 3D printers have been developed and shared by an open source community. [ 14 ] We therefore recognized that such a printer could be used as a comprehensive research tool kit if converted to allow processing of solutions instead of solid fi laments. Furthermore, we also recognized that 3D printers have a number of other advantages over conventional printers/coaters. As a 3D printer is controlled by digital code, no hardware change is required to vary the printing pattern, allowing different device structures or designs to be tested without preparing new masks, forms, or other physical patterning. The digital instruction protocol, G code, is a machine-independent standard which means that optimized printing conditions can be transferred from machine Solution-processed solar cells continue to show great promise as a disruptive energy generation technology due to their inherently low manufacturing costs and increasing effi ciencies. [ 1–3 ]

A new iron(iii) 2,4,6-trimethylbenzenesulfonate (MSA) with composition [Fe(OH2)5(MSA)3] has been prepared from the reaction of Fe(OH)3·xH2O and three molar equivalents of 2,4,6-trimethylbenzenesulfonic acid and used as oxidant in the preparation of highly conducting polypyrrole (PPy) and poly(3,4-ethylenedioxythiophene) (PEDOT) films for the first time. PPy and PEDOT films grown on non-conducting overhead transparency (polyethylene terephthalate films) using a vapour phase polymerization technique exhibited very high conductivities; 200 ± 20 S cm–1 for PPy and 1000 ± 80 S cm–1 for PEDOT.