Evaluation of a hybrid hydrostatic bearing for cryogenic turbopump application

A hybrid hydrostatic bearing was designed to operate in liquid hydrogen at speeds to 80,000 rpm and radial loads to 440 n (100 lbf). The bearing assembly consisted of a pair of 20-mm angular-contact ball bearings encased in a journal, which was in turn supported by a fluid film of liquid hydrogen. The size and operating conditions of the bearing were selected to be compatible with the operating requirements of an advanced technology turbopump. Several test parameters were varied to characterize the bearing's steady-state operation. The rotation of the tester shaft was varied between 0 and 80,000 rpm. Bearing inlet fluid pressure was varied between 2.07 and 4.48 MPa (300 and 650 psia), while the fluid sump pressure was independently varied between 0.34 and 2.07 MPa (50 and 300 psia). The maximum radial load applied to the bearing was 440 N (110 lbf). Measured hybrid-hydrostatic-bearing stiffness was 1.5 times greater than predicted, while the fluid flow rate through the bearing was 35 to 65 percent less than predicted. Under two-phase fluid conditions, the stiffness was even greater and the flow rate was less. The optimal pressure ratio for the bearing should be between 0.2 and 0.55 depending on the balance desired between bearing efficiency and stiffness. Startup and shutdown cyclic tests were conducted to demonstrate the ability of the hybrid-hydrostatic-bearing assembly to survive at least a 300-firing-duty cycle. For a typical cycle, the shaft was accelerated to 50,000 rpm in 1.8 sec. The bearing operated for 337 start-stop cycles without failure

Using metrics and sustainability considerations to evaluate the use of bio-based and non-renewable Brønsted acidic ionic liquids to catalyse Fischer esterification reactions

Background Ionic liquids have found uses in many applications, one of which is the joint solvation and catalysis of chemical transformations. Suitable Brønsted acidic ionic liquids can be formed by combining lactams with sulphonic acids. This work weighs up the relative benefits and disadvantages of applying these Brønsted acidic ionic liquid catalysts in esterifications through a series of comparisons using green chemistry metrics. Results A new bio-based ionic liquid was synthesised from N-methyl pyrrolidinone and p-cymenesulphonic acid, and tested as a catalyst in three Fischer esterifications under different conditions. An evaluation of the performance of this Brønsted acidic ionic liquid was made through the comparison to other ionic liquid catalysts as well as conventional homogeneous Brønsted acids. Conclusion Extending the argument to feedstock security as well as mass utilisation, ultimately in most instances traditional mineral acids appear to be the most sensible option for Brønsted acid esterification catalysts. Ester yields obtained from Brønsted acidic ionic liquid catalysed procedures were modest. This calls into question the diversity of research exploring esterification catalysis and the role of ionic liquids in esterifications

Compliance with herpes zoster vaccination in young and adult individuals in two regions of Italy

Background: The purpose of this work was to explore the knowledge and acceptance of Varicella Zoster Virus (VZV)- Herpes Zoster (HZ) vaccination in the general Italian population, where the HZ vaccine has not yet been distributed, using a prevalence study of subjects from two regions in Italy. Methods: A group of 3,173 individuals were interviewed using a questionnaire. The youngest age group (≤ 20 year) was composed of students interviewed at university. The middle age group (21-40 years) and the older age group (≥ 41 years) were interviewed by general practitioners in their office. Results: In both regions, the majority of subjects had been infected with varicella, and only 165 (5.2%) subjects reported receiving the VZV vaccination. Regarding HZ, 2,749 (86.6%) individuals stated that they knew of the virus and 2,233 (70%) were willing to be vaccinated against HZ. The majority of people willing to be vaccinated were in the middle and older age groups (36.6% and 44.7%, respectively). Conclusion: Compliance versus vaccination results were satisfactory and probably, with the upcoming availability of the HZ vaccine in Italy, adults will be favourably disposed towards vaccination

The regulation of IL-10 expression

Interleukin (IL)-10 is an important immunoregulatory cytokine and an understanding of how IL-10 expression is controlled is critical in the design of immune intervention strategies. IL-10 is produced by almost all cell types within the innate (including macrophages, monocytes, dendritic cells (DCs), mast cells, neutrophils, eosinophils and natural killer cells) and adaptive (including CD4(+) T cells, CD8(+) T cells and B cells) immune systems. The mechanisms of IL-10 regulation operate at several stages including chromatin remodelling at the Il10 locus, transcriptional regulation of Il10 expression and post-transcriptional regulation of Il10 mRNA. In addition, whereas some aspects of Il10 gene regulation are conserved between different immune cell types, several are cell type- or stimulus-specific. Here, we outline the complexity of IL-10 production by discussing what is known about its regulation in macrophages, monocytes, DCs and CD4(+) T helper cells

BIOMONITORING OF NURSES OCCUPATIONALLY EXPOSED TO ANTINEOPLASTIC DRUGS: THE IMEPA PROJECT

Objective: to develop a multiple-endpoint monitoring system in order to assess and minimize long term risks in hospital nurses exposed to antiblastic drugs. Design: molecular epidemiology study. Setting: S. Orsola-Malpighi Hospital in Bologna, Italy nurses exposed to antiblastic drugs. Participants: 50 exposed subjects (8 males and 42 females) and 50 unexposed individuals (8 males and 42 females) matched for age and smoking habits. Main outcome measures: urinary markers of exposure; Heat Shock Proteins (HSPs) 27, 70, 90, 110; immunological biomarkers in peripheral blood lymphocytes; apoptosis, cell-cycle analysis G1-S-G, typization of Natural Killer cells (NK) and receptors for IL-2 in peripheral blood lymphocytes; micronuclei: frequency in peripheral blood lymphocytes and in exfoliated buccal mucosa cells; activation of specific oncogenes (bax, bcl2, b-actin). Results: 19/50 subjects showed urinary antiblastic drugs levels (3 subjects MTX, 11 subjects CP, 5 subjects MTX and CP). No statistically significant differences were observed in all the considered biomarkers between the exposed and control groups. Conclusion: this biomonitoring study doesn’t evidence any early significant effect associated to the exposure to antiblastic drugs

Identificazione di marcatori specifici di esposizione professionale a farmaci antiblastici usati in polichemioterapia: Progetto IMEPA.

OBJECTIVE: To develop a multiple-endpoint monitoring system in order to assess and minimize long term risks in hospital nurses exposed to antiblastic drugs. DESIGN: Molecular epidemiology study. SETTING: S. Orsola-Malpighi Hospital in Bologna, Italy: nurses exposed to antiblastic drugs. PARTICIPANTS: 50 exposed subjects (8 males and 42 females) and 50 unexposed individuals (8 males and 42 females) matched for age and smoking habits. MAIN OUTCOME MEASURES: Urinary markers of exposure, Heat Shock Proteins (HSPs) 27, 70, 90, 110, immunologic biomarkers in peripheral blood lymphocytes: apoptosis, cell-cycle analysis G1-S-G, typization of Natural Killer cells (NK) and receptors micronuclei; frequency in peripheral blood lymphocytes and in exfoliated buccal mucosa cells; activation ofspecific oncogenes (bax, bcl2). RESULTS: 19/50 subjects showed urinary antiblastic drug levels (3 subjects MTX, 11 subjects CP, 5 subjects MTX and CP). No statistically significant differences were observed in all the considered biomarkers between the exposed and control groups. CONCLUSION: This biomonitoring study doesn't evidence any early significant effect associated to the exposure to antiblastic drugs