3-Mercaptopropionate (3-MPA) is a major hydrophilic thiol in salt marsh sediments from Shelter Island, New York. It is associated mainly with the sedimentary particulate phase, although the mechanism ...of its binding has not been clear. In this study, we show that humic substances coated on clay minerals are involved in binding 3-MPA through di- and poly-sulfide linkages. With increasing depth, the abundance of 3-MPA in the fulvic acid fraction decreases with a concomitant increase in the humic acid fraction, suggesting that, with depth, fulvic-bound 3-MPA is converted into humic-bound 3-MPA. We modeled the depth variation with a multi-G model which suggests that there are two types of reactive components in both fulvic acid-bound and humic acid-bound 3-MPA, one changing about 10 times more rapidly than the other. These two 3-MPA pools probably reflect different types of sulfur bridging, with the polysulfide-bridged pool changing more rapidly than the disulfide-bridged pool. As free thiol, 3-MPA is attacked relatively rapidly by anaerobic bacteria, its degradation following firstorder kinetics. However, in the sediment core we studied, humic-bound 3-MPA was present throughout the sediment column, down to 22 cm, corresponding to an age of about 90 years. These results suggest that thiols can escape bacterial degradation in sediments by binding to humic substances. The sedimentary distribution of 3-MPA is an important illustration of the interplay of biological and chemical processes in the fate of thiols in anoxic marine sediments.
In numerous recent studies attention has been focused to neuroendocrine differentiation (NED) in prostate cancer (PC). Focal NED is present in almost all PCs, but it is prominent in only 5-10% of the ...carcinomas. The prognostic significance of focal NED in PC is controversial, but current evidence suggests its influence on the onset and/or conversion of hormone resistant tumor phenotype. The aim of this study was to evaluate the relationship between NED status, based only on immunohistochemical use of neuroendocrine (NE) markers, with PC grade and stage, and preoperative serum levels of prostate-specific antigen (PSA).
The study included the biopsy material of 73 untreated PC patients (pts.) obtained by transurethral resection (TUR) (37 pts.), and radical retropubic prostatectomy (RRP) (36 pts.). Two representative tissue samples (typically the block containing the largest amount of neoplasm) were selected for immunohistochemical (IMM) staining. NE cells were identified using a panel of IMM markers: chromogranin A, neuron-specific enolase, and serotonin. The level of PC exocrine differentiation was detected by monoclonal antibodies against PSA.
Significant expression of NE cells was demonstrated in 26 (70.2%) pts. with PC after TUR. In this group, serum preoperative PSA values ranged from 0.1 to 9.6 ng/ml. The majority of pts. with NED had low differentiated PC with Gleason grade score (GGS) > 7, and normal PSA values below 4 ng/ml (77%), in clinical stage D (54%). Statistically significant correlation (p<0.01) of positive NED with higher stage and grade and low PSA values was established. Among the pts. with localized PC in whom RRP was performed (n=36), significant expression of NE cells was found in 15 pts. (41.7%), 8 (53.3%) in pT2 stage, and 7 (46.7%) in pT3 stage. Significant correlation between NED with preoperative PSA values and stage of PC in pts. with RRP was not found.
We demonstrated the significant NED in poorly differentiated PC in patients in the advanced stage of the disease. The expression of NED in organ-confined PC did not correlate with tumor stage, but it correlated with tumor grade (GGS < or = 7).
The Muon Ionization Cooling Experiment (MICE) collaboration has developed the MICE Analysis User Software (MAUS) to simulate and analyze experimental data. It serves as the primary codebase for the ...experiment, providing for offline batch simulation and reconstruction as well as online data quality checks. The software provides both traditional particle-physics functionalities such as track reconstruction and particle identification, and accelerator physics functions, such as calculating transfer matrices and emittances. The code design is object orientated, but has a top-level structure based on the Map-Reduce model. This allows for parallelization to support live data reconstruction during data-taking operations. MAUS allows users to develop in either Python or C++ and provides APIs for both. Various software engineering practices from industry are also used to ensure correct and maintainable code, including style, unit and integration tests, continuous integration and load testing, code reviews, and distributed version control. The software framework and the simulation and reconstruction capabilities are described.
In view of the association of hyperinsulinemia with elevated luteinizing hormone (LH) levels and hyperandrogenism in polycystic ovary syndrome (PCOS), the effect of octreotide was investigated in ...women with PCOS. Twelve amenorrheic women were treated with 100 micrograms octreotide twice a day for 7 days; 13 infertile women unresponsive to clomiphene citrate were treated either with octreotide (100 micrograms twice a day from day 1 of the menstrual cycle until corpus luteum formation) in addition to human menopausal gonadotropins (HMG) or with HMG alone. Octreotide significantly reduced the 4-hour integrated LH concentrations. LH pulse amplitude and nadir concentrations, and LH, testosterone, androstenedione, and estradiol responses to a gonadotropin-releasing hormone (GnRH) analogue in amenorrheic PCOS women. Octreotide treatment also resulted in a more "appropriate" hormonal milieu at the time of human chorionic gonadotropin (HCG) injection in the infertile women, with LH and testosterone levels being reduced while follicle-stimulating hormone (FSH) levels increased. Orderly follicular growth occurred, with one or two mature follicles being present at the time of HCG injection in cycles in which octreotide was given together with HMG. There were no cases of hyperstimulation, even in women who had previously hyperstimulated after HMG alone. Octreotide thus inhibits LH and androgen secretion and may improve ovulatory performance in infertile women with PCOS.
Exact physical model for magnets in storage rings Maletic, D.; Ruggiero, A.G.
AIP Conference Proceedings (American Institute of Physics); (United States),
11/1992, Letnik:
292:1
Conference Proceeding
Recenzirano
In this report we try to make estimates of both kinematic and field effects on the stability of a particle motion, by employing a truly Maxwellian representation of the magnetic field in exact ...equations of motion. For this purpose we adopt a simple FODO cell model, which repeats periodically to infinity. This model includes only quadrupoles and drifts, leaving out the bending magnets to avoid the problem of the trajectory curvature. We think this model is a physically consistent approximation of a storage ring. We derive several models with different levels of approximation and compare them by evaluating the importance of these effects. The relevance to long-term stability is being investigated in the meantime by comparing the different models with extensive computer simulations. The results will be shown in a subsequent report. (AIP)
Since nitric oxide (NO) in many cells is involved in energy metabolism, the aim of this study was to evaluate the role of isosorbide dinitrate (ISDN), a NO donor, in energy metabolism of rat ...reticulocytes, particularly due to their high content of hemoglobin--an effective scavenger of NO. Rat reticulocyte-rich red blood cell suspensions were aerobically incubated in the absence (control) or in the presence of different concentrations of ISDN. ISDN decreased total and coupled oxygen consumption (p<0.05) while increased uncoupled oxygen consumption (p<0.05) in a dose- and time-dependent manner. This was followed by enhancement of glycolysis, as measured by increased glucose consumption and lactate accumulation (p<0.05). Levels of all glycolytic intermediates in the presence of ISDN indicate only stimulation of pyruvate kinase activity. ISDN did not alter the concentration of ATP, while increased ADP and AMP levels (p>0.05). In rat reticulocytes under steady-state conditions, 95.4% of overall energy was produced by oxidative phosphorylation but only 4.6% by glycolysis. Due to a reduced coupled oxygen consumption in the presence of ISDN, ATP production via oxidative phosphorylation was significantly diminished. A simultaneous increase of glycolytic ATP production is not enough to ensure constant ATP production. The calculated mean ATP turnover time was prolonged by 199% in the presence of 1.5 mmol/l ISDN. In conclusion, ISDN a) inhibited total and coupled respiration but enhanced uncoupled respiration, b) stimulated glycolysis, c) decreased ATP production and d) prolonged ATP turnover time in rat reticulocytes. These effects were mediated by NO as the effector molecule.
In this paper we discuss the synergisms between different realms of plasma supported nanotechnologies. First the developments in plasma etching for micro and later nanoelectronics have fueled immense ...growth of knowledge and tools in describing non-equilibrium plasmas. This has led to detailed predictive codes and that knowledge has been used to develop a large number of new sources of non-equilibrium plasmas operating at atmospheric pressure, even in air. With those tools a new front of plasma medicine has opened wide with new possibilities and a number of promising techniques for sterilization, cancer treatment, oral cavity treatment, dermatology and in a range of applications where deposition of thin films for biocompatibility is necessary. This new front opens new possibilities in the realm of nanotechnologies with atmospheric pressure deposition of nano-structures allowing direct application of new techniques in medicine and in cheaper technologies for other purposes.
This paper presents a comparative analysis of main indicators of the financial results and the financial position of food industry enterprises in Vojvodina performed over the five-year period of ...transition (2002-2006). Cumulative balances were used as basic data sources. The performance of food industry enterprises is usually compared with performances of agricultural companies. During three out of five observed years, the food industry achieved a negative net financial result. The rates of income on the gross invested capital were also very modest (3.39-6.15%). The finacial structure was very unfavourable, which created problem with maintaining the solvency. The turnover fund was sufficient for the coverage of approximately 56% of permanent stocks, which means that companies were missing 54%, or about 18 billion dinars of long-term available resources only for the establishment of the financial balance. The gross capital value of food industry companies increased by about 75%, while the real value of the net capital increased by 39.6 index points.
This paper presents a study, which examines the role of maintenance regarding improving product quality and company's profitability. The empirical data for this study was drawn from a Slovenian ...company in order to address the research problem. The main results of the case study showed, that 3.22 % of profit could be generated at weaving machine, if all unplanned stoppages and loss of quality due to decrease in the productivity would be prevented. Results also showed that due to productivity improvement, quality rate would be improved for approximately 2 %. These findings therefore, indicate that maintenance has impact on product quality and company's profitability. Thus, these findings also acknowledge maintenance's potential of increasing the overall profit.
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