Stepan (United States)

I recall the day when Laurence Charles and Richard Cole approached me to be a guest editor for a special issue honoring the life work of my former PhD adviser and friend, Distinguished Professor Chrys Wesdemiotis, at The University of Akron. It took me less than one second to say I would be honored to participate because of how Chrys made an impact, not just on my life, but for the countless others who have worked with him over the years. Many of us know Chrys for his vast scientific achievements, crossing multi-disciplinary fields of research. However, only a select group of his former students and postdocs can truly appreciate Chrys and his impact on our lives throughout the years. Chrys has been an integral part of celebrating our successes in the lab, mentoring us through challenging times, and being part of our lives even well beyond our studies and research on campus. In this reminiscence article, a group of former and current students will comment on how Chrys is special to us, and we genuinely appreciate him being our adviser, mentor, and friend. We are thrilled to see Chrys being honored with this special issue of Mass Spectrometry Reviews! Bryan Katzenmeyer, PhD Director, Mass Spectrometry Business at JEOL.

Abstract Hydrocarbon spills can occur at various stages of the oil and gas exploration and production workflow. It would be beneficial to be able to treat these spills on-site to avoid more expensive excavation and incineration processes. This study aims to optimize the use of rhamnolipid biosurfactants for enhancing the bioremediation of hydrocarbon-contaminated soil. The goal of this work was to explore the effects of rhamnolipid application on hydrocarbon degradation rate under both laboratory and field conditions, and to examine the effects of this treatment on the indigenous soil microorganism population. The results have demonstrated the potential for rhamnolipids to enhance the remediation of petroleum hydrocarbons in contaminated soils. The laboratory experiments showed that the application of rhamnolipids at above 0.5g/kg was effective in increasing bacteria activity in the soil. Knowledge from the lab tests was used to design the field experiments, and the respirometry results were combined with biological stoichiometric calculations to determine the appropriate nutrient loading for the field site. Lab tests are a critical prerequisite for understanding bioremediation mechanisms for a particular contaminated site and designing an effective field treatment program. The field results correlated with the laboratory respirometry results, and the field study confirmed that the application of rhamnolipid in combination with ammonium chloride as the nitrogen source was able to improve the overall health of the soil. Bacterial analysis demonstrated that addition of rhamnolipid enriched the soil in Pseudomonas and Serratia bacterial species, which are known hydrocarbon degraders. Additionally, these strains were shown to degrade rhamnolipid, and this affirms the beneficial aspect that applied rhamnolipid won't accumulate and persist in the environment. Overall, this work provides insight into the combination of laboratory and field studies when using rhamnolipids to enhance bioremediation of contaminated soils.

Obstructive uropathy is an important cause of acute and chronic kidney disease. Decompression of the urinary tract is an essential aspect of treatment. The cause and aetiology of obstruction typically determine the surgical approach. Acute relief of obstruction is frequently complicated by fluid and electrolyte imbalance. Standard therapeutic interventions for acute or chronic renal failure also apply for cases of obstructive uropathy. This narrative review summarises the early and long-term medical management of obstructive uropathy.

Дмитрук В

Se-containing catalysts of organic and inorganic nature were explored for the synthesis of acrylic acid and its esters in different solvents. Newly synthesized Se-containing microgel catalyst shown the best catalytic performance. With microgel catalyst different acrylate monomers can be produced with high yield simply by varying solvent nature.

Depresija je najčešći afektivni poremećaj koji se javlja kao posljedica moždanog udara, takođepovezana i sa značajno otežanim ponovnim uspostavljanjem funkcionalnosti i kvaliteta života. Ciljrada bio je utvrđivanje značaja depresije na kvalitet života nakon moždanog udara, te utvrđivanjestatističke značajnosti razlike depresivnog i nedepresivnog pacijenta nakon moždanog udara.Uispitivanje je bilo uključeno 50 pacijenata u kontrolnoj grupi, kao i 50 pacijenata u eksperimentalnojgrupi, oba pola, starosti od 18 do 86 godina života, hospitalizovanih na Klinici za psihijatriju i Kliniciza neurologiju, Univerzitetsko Kliničkog centra u Banjoj Luci, zbog klinički dijagnostikovanogakutnog moždanog udara. Postojanje depresije procjenjivano je na osnovu autoanamnestički dobijenihpodataka, kliničkog posmatranja. Za dijagnozu depresivnog poremećaja koristili smo MiniInternacionalni Neuropsihijatrijski Inervju (MINI), a za procjenu težine depresije upotrebljavali smoHamiltonovu skalu za procjenu depresivnosti (HAMD), verziju sa 17 ajtema. Short form (SF-36verzija 2.0) upitnik se koristio za procjenu kvaliteta života, omogućavajući da se otkrije uticajrazličitih oboljenja na kvalitet života. Minor depresiju (skor HAMD 8-15) imalo je 50% (25pacijenata), kao i major depresiju (skor HAMD ≥ 16) je imalo 50% (25 pacijenata). Dobijenevrijednosti ukazuju da je kvalitet života nakon moždanog udara značajno umanjen u odnosu na kvalitetživota prosječne populacije (50.0). Nije prisutna statistički značajna razlika u težini poremećajakvaliteta života kod pacijenata sa i bez depresivnog poremećaja (Mann-Whitney U, p=0.526).

Introduction: Liposomes are the most established nanocarriers that can be loaded with contrast agents as well as tailored for targeting to the desired tissue. Targeted CT liposomes represent a novel approach for rapid thrombus imaging. They allow specific and selective accumulation in thrombus providing significant contrast enhancement (expressed as HU) over the surrounding tissue. Hypothesis: We hypothesize that preparation technology will produce homogenous liposomes with sufficient level of loaded CT contrast agent. Methods: Liposomes were composed of distearoyl phosphatidylcholine, cholesterol, and distearoyl phosphatidylethanolamine - polyethylene glycol 2000 (molar ratio, 55/45/5). CT liposomes were prepared by lipid film hydration with iohexol (Omnipaque 350, GE Healthcare) followed by freeze-thaw extrusion (100 nm). Subsequently, they were purified by dialysis (Slide-A-Lyzer, cut-off 10 kDa) to remove un-loaded ioxehol. After purification, liposome-associated iohexol was determined by UV/VIS spectrophotometry and CT. Size distribution of final CT liposomes was assessed by dynamic light scattering. Results: Preparation technology produced homogenous liposome population having appropriate size distribution (90-110 nm and PD index, 0.05-0.10). Iohexol that remains associated in final CT liposomes represented only 5% of its initial level entering the preparation process. Almost 95% of iohexol was released and its final content was found to be 5 mg iodine/ml. Conclusions: Liposomal CT formulation was prepared with satisfactory size distribution and homogenity. Although the significant portion of iohexol was released, these CT liposomes were still detectable in vitro by CT. This basic liposomal platform will be optimized to achieve higher iohexol loading and will be further developed for thrombus imaging such as targeted CT liposomes.

Each of those volumes presented important new work that is representative of the plethora of publications on trilobite taxonomy, taphonomy, anatomy and palaeoecology that have appeared within the last 50 years. The meetings have also served a function in bringing the dispersed international community of specialists together and defining common goals. For example, completion of the revised trilobite volume of the Treatise on invertebrate paleontology (Kaesler 1997) and the list of all existing trilobite genera of Jell & Adrain (2003), both important milestones, benefited from the meetings.