A solid ceramic electrolyte system for measuring redox conditions in high temperature gas mixing studies

The details of the construction and operation of a gas mixing furnace are presented. A solid ceramic oxygen electrolyte cell is used to monitor the oxygen fugacity in the furnace. The system consists of a standard vertical-quench, gas mixing furnace with heads designed for mounting the electrolyte cell and with facilities for inserting and removing the samples. The system also contains the highinput impedance electronics necessary for measurements and a simplified version of standard gas mixing apparatus. The calibration and maintenance of the system are discussed

Quantum Repeaters using Coherent-State Communication

We investigate quantum repeater protocols based upon atomic qubit-entanglement distribution through optical coherent-state communication. Various measurement schemes for an optical mode entangled with two spatially separated atomic qubits are considered in order to nonlocally prepare conditional two-qubit entangled states. In particular, generalized measurements for unambiguous state discrimination enable one to completely eliminate spin-flip errors in the resulting qubit states, as they would occur in a homodyne-based scheme due to the finite overlap of the optical states in phase space. As a result, by using weaker coherent states, high initial fidelities can still be achieved for larger repeater spacing, at the expense of lower entanglement generation rates. In this regime, the coherent-state-based protocols start resembling single-photon-based repeater schemes.Comment: 11 pages, 8 figure

Imaging Microglial/Macrophage Activation in Spinal Cords of Experimental Autoimmune Encephalomyelitis Rats by Positron Emission Tomography Using the Mitochondrial 18kDa Translocator Protein Radioligand [18F]DPA-714

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the CNS. Activated microglia/macrophages play a key role in the immunopathogenesis of MS and its corresponding animal models, experimental autoimmune encephalomyelitis (EAE). Microglia activation begins at early stages of the disease and is associated with elevated expression of the 18 kDa mitochondrial translocator protein (TSPO). Thus, positron emission tomography (PET) imaging of microglial activation using TSPO-specific radioligands could be valuable for monitoring disease-associated neuroinflammatory processes. EAE was induced in rats using a fragment of myelin basic protein, yielding acute clinical disease that reflects extensive spinal cord inflammation. Enhanced TSPO expression in spinal cords of EAE rats versus those of controls was confirmed by Western blot and immunohistochemistry. Biodistribution studies in control and EAE rats were performed using the TSPO radioligand [18F]DPA-714 [N,N-diethyl-2-(2-(4-(2-fluoroethoxy)phenyl)-5,7-dimethylpyrazolo[1,5-a]pyrimidin-3-yl)acetamide]. At 1 h after injection, almost fivefold higher levels of [18F]DPA-714 were measured in spinal cords of EAE rats versus controls. The specific binding of [18F]DPA-714 to TSPO in spinal cords was confirmed in competition studies, using unlabeled (R,S)-PK11195 [(R,S)-N-methyl-N-(1-methylpropyl)-1-(2-chlorophenyl)isoquinoline-3-carboxamide)] or DPA-714 in excess. MicroPET studies affirm that this differential radioactivity uptake in spinal cords of EAE versus control rats could be detected and quantified. Using [18F]DPA-714, neuroinflammation in spinal cords of EAE-induced rats could be visualized by PET, offering a sensitive technique for monitoring neuroinflammatory lesions in the CNS and particularly in the spinal cord. In addition to current MRI protocols, this approach could provide molecular images of neuroinflammation for detection, monitoring, and research in MS

CO2 Increase: Questions Beyond Climate Change

The increase of the tropospheric C02 (carbon dioxide) concentration is considered by scientists all over the world to be an alarming signal, as becomes evident from the huge amount of literature on the subject. The so-called greenhouse-gas effect, or, more precisely, its anthropogenic component, is mainly caused by the C02 increase. However, other trace gases have also contributed their share. Far-reaching climatic changes, a temperature increase in the tropospheric air, especially in the polar region, as well as a gradual melting of the Greenland and Antarctic ice with a simultaneous rise of the seawater level, are being predicted as a consequence of the greenhouse effect. In addition to these gloomy prospects a new hypothesis has developed: The biological consequences of the evolution of a changed composition of the air could be hazardous to man and nature

Structure elucidation of some insect pheromones : a contribution to the development of selective pest control agents

The use of pheromones is one of the methods currently being investigated intensively as an alternative method of insect control. The various ways in which pheromones might be used in insect control programmes are briefly discussed in Chapter 1.Chapter 2 gives a detailed description of the isolation and identification of the sex pheromone of the American cockroach, Periplaneta americana. The various techniques that have been used for the structure elucidation are described.The sex pheromone of P. americana contains two major components (periplanone-A and periplanone-B), as well as minute amounts of another four.Periplanone-B could be identified as (1 Z, 5 E)-1,10(14)-diepoxy- 4(15), 5-germacradiene-9-one. Periplanone-A proved to be very unstable, isomerizing to a biologically inactive compound. The instability of the compound rendered a complete structure elucidation impossible.The four minor compounds could not be collected in sufficient amounts to carry out a complete structure elucidation.Of the compounds reported to mimic the natural pheromone, only germacrene-D was found to do so. However, its threshold is very much higher than that of the natural pheromone. The same holds for the other reported mimics, even they do elicit electroantennogram responses. Regardless of concentration, none of the mimics elicit responses as marked as the natural pheromone.Apart from causing sexual excitation, periplanone-B also can attract males of P. americana.The isolation, identification and field evaluation of the sex pheromone of the leafroller moth, Archips podana, is described in Chapter 3. The pheromone consists of a mixture of equal amounts of cis -11-tetradecenyl acetate and trans -11-tetradecenyl acetate. Although the individual compounds are not attractive in field experiments, a 1:1 mixture of the two is capable of attracting many males of this species.Investigation of the sex pheromone of the false codling moth, Cryptophlebia leucotreta (Chapters 4 and 5) revealed that the pheromone is a mixture of equal amounts of cis -8-dodecenyl acetate and trans -8-dodecenyl acetate. This finding contradicts other reports which state that the pheromone of this insect is trans -7-dodecenyl acetate. Mixtures of cis -8- and trans -8-dodecenyl acetate in various ratios proved to be very attractive to males of this species.In Chapter 6 the isolation, identification and field evaluation of the sex pheromone of the potato tuberworm moth, Phthorimaea operculella, is described. The sex pheromone of this moth is a mixture of about equal amounts of trans -4, cis -7-tridecadienyl acetate and trans -4, cis -7, cis -10-tridecatrienyl acetate. These findings were confirmed by synthesis and by trapping experiments in the field

Mixed-Cation Zeolites with Minimum Lithium and Silver for Air Separation

Air separation is a key process in today’s industry and is achieved by various methods including but not limited to the energy intensive cryogenic distillation of liquefied air and pressure swing adsorption process. The cryogenic process is preferable for high-volume production of Oxygen and Nitrogen from atmospheric air while the pressure swing adsorption process is more applicable for low-to-medium volume production. In this dissertation, we focused mainly on air separation by adsorption which is based on the unique adsorption property of zeolites with high N2/O2 selectivities. An introductory chapter is presented here-in that gives an in-depth picture of various air separation processes and technologies. The second chapter evaluates carbon dioxide, water vapor, and methane on Li-LSX (where LSX denotes low-silica X-zeolite with Si/Al = 1.0) as a superior adsorbent for air separation at low pressure. Characteristic adsorption isotherms to very low partial pressures (to a few ppm at 1 atm) were measured for Li-LSX and compared with the conventional synthetic 13X zeolite as well as two ion-exchanged zeolites in K-LSX and Ca-LSX. Though Li-LSX has been the sorbent of choice since its invention for air separation by pressure swing adsorption and vacuum swing adsorption, the demand for lithium has steeply risen due to its application in lithium ion-batteries for energy storage as well as the fact that its reserves are dwindling, thereby driving up its cost, we set out in the third chapter to develop new zeolites in which lithium is substantially reduced and replaced by a low cost alkali-earth metal cation, in this case, Ca2+. To accomplish this ground-breaking task, mixed-cation LiCa-LSX zeolites containing minimum lithium were prepared by exchanging small fractions of Li+ into Ca-LSX, followed by dehydration under mild conditions to avoid equilibration/migration of the lithium cations. Results after comparing the mixed-cation samples against the pure-cation samples based on their oxygen productivity performance by pressure swing adsorption via a model simulation showed that the LiCa-LSX samples yielded significantly higher O2 product productivities at the same product purity and recovery than their pure-cation precursor, Ca-LSX and only 25% less the Li-LSX. Chapter 4 involves the desulfurization of natural gas using nitrogen-doped carbon. Comparisons of adsorption isotherms for hydrogen sulfide and methane showed that the nitrogen-doped carbon sample (7 wt% N2) adsorbs hydrogen sulfide 5 times more and adsorbs methane 1.3 times less than commercial Calgon BPL 12x30 activated carbon respectively. The regeneration energy required for the synthesized nitrogen-doped carbon sample was very low and required approximately 8 minutes at 333 K for complete hydrogen sulfide desorption. In chapter 5, more mixed-cations, LiSr-LSX, AgCa-LSX and AgSr-LSX containing minimum lithium and silver were prepared by exchanging small fractions of Li+ into Sr-LSX and Ag+ into Sr-LSX and Ca-LSX respectively. Strong evidences were provided that significant fractions of the exchanged Li+ and Ag+ remained in SIII and SII* respectively after comparisons of the N2/O2 adsorption isotherms and isosteric heats of adsorption of the mixed-cation and pure-cation samples. Chapter 6 covers the study of Sr-LSX zeolite and its possibility of completely replacing Li-LSX for air separation in adsorption processes. The O2 productivity performance results from this study were quite promising and are discussed in detail along with treatment conditions for adsorption capacity optimization.PHDChemical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttps://deepblue.lib.umich.edu/bitstream/2027.42/145969/1/epiepang_1.pd

Quantification of anandamide content in animal cells and tissues: the normalization makes the difference

Anandamide (N-arachidonoylethanolamine, AEA) is an endogenous lipid that binds to cannabinoid receptors in the central nervous system and in peripheral cells. Quantitative analysis of AEA is generally based on the normalization to the fresh weight of the samples. Here, we show that the normalization procedure of AEA content is such a critical factor, that it might introduce per se significant discrepancies in the quantification of AEA even in the same sample. We suggest that a rapid, accurate and most reliable reference to quantify AEA and congeners from different sources is the protein content, a common parameter to cells and tissues

Development of a versatile [68Ga]Ga-FAPI-46 automated synthesis suitable to multi-elutions of germanium-68/gallium-68 generators.

peer reviewedGallium-68-labeled FAPI-46 has recently been proposed as a novel positron emission tomography imaging probe to diagnose and monitor a wide variety of cancers. Promising results from several ongoing clinical trials have led to a soaring demand for this radiotracer. Typical [68Ga]Ga-FAPI-46 labeling protocols do not cope with multiple generator elutions, leaving radiopharmacies unable to scale-up the production and meet the demand. Here, we propose a robust and efficient automated radiosynthesis of [68Ga]Ga-FAPI-46 on the Trasis miniAllinOne synthesizer, featuring a prepurification step which allows multiple generator elutions and ensures compatibility with a wide range of gallium-68 generators. Our approach was to optimize the prepurification step by first testing five different cationic cartridge chemistries. Only the strong cationic exchange (SCX) cartridges tested had sufficient affinities for quantitative trapping of >99.9%, while the weak cationics did not exceed 50%. Packaging, rinsing, or flowing of the selected SCX cartridges was not noticeable, but improvements in fluidics managed to save time. Based on our previous development experience of [68Ga]Ga-FAPI-46, radiolabeling optimization was also carried out at different temperatures during 10 min. At temperatures above 100°C, radiochemical yield (RCY) > 80% was achieved without significantly increasing the chemical impurities (88%). A comparison with radiosyntheses carried out without prepurification steps was also conclusive in terms of RCY, radiochemical yield, and chemical purity. Finally, high-activity tests using elutions from three generators were also successful for these parameters. [68Ga]Ga-FAPI-46 was consistently obtained in good radiochemical yields (>89%, n = 3), and the final product quality was compliant with internal specifications based on European Pharmacopoeia. This process is suitable for GMP production and allows scaling-up of routine productions, higher throughput, and, ultimately, better patient care