Downlink capacity and interference statistics of wideband code division multiple access microcells for trains in long tunnels

The wideband code division multiple access downlink interference statistics and the capacity of equally spaced tunnel cigar-shaped microcells, used to serve users travelling in trains or metros, are analysed. The hybrid propagation model, with two defined modes, is used in the analysis. Fast fading because of multipath interference is superimposed with the main value of the loss and the slow fading up to a certain distance beyond which it can be neglected. To calculate the interference statistics and the capacity, a scenario with ten cigar-shaped microcells has been considered. The downlink capacity is then derived for different sector radii, train lengths, break point distances and propagation parameters. It is found that increasing the sector range up to 1250 m increases the sector downlink capacity. It is noticed that the maximum downlink capacity can be obtained for a sector radius of 1250-1750 m. It is also found that the increment of the propagation parameter gamma reduces the sector downlink capacity. It is also noticed that increasing the train length increases the downlink capacity. It is also found that the bend loss increases the downlink capacity and reduces the maximum sector range.     

Cochannel and adjacent channel interference in actual terrestrial TV scenarios - part II: MATV systems laboratory tests

For pt.I, see Sanchez, M.G. et al., ibid., p.111-15. The results of an extensive study on analog PAL signals interfered with by digital DVB-T signals are presented. The study covers a theoretical evaluation of the interference problems, field and laboratory measurements and a national survey among TV installation companies. Field measurements are reported in part I. These measurements explain the origin of cochannel and some of the adjacent channel interference problems. However, interference was reported in areas where the field measurements showed that the protection ratios for PAL signals interfered with by DVB-T adjacent channel signals were met. As these reports came from multistorey buildings with master antenna TV (MATV) installations, the study was extended to analyze the role of these installations in the interference problems. Part of the interference problems are due to the MATV system amplifiers which are unable to cope with adjacent channel DVB-T signals. The nonlinear amplifiers give rise to intermodulation problems. The ITU-R recommendations (see ITU-R BT.1368, 2000) recognize that such nonlinear amplifiers could be a source of problems and that higher protection ratios may be needed, but no value is given for the increase. Our laboratory tests of commercial amplifiers found that an increase in the protection ratios of between 12 to 16 dB is needed to avoid a significant degradation of the PAL TV signal in the amplifiers. It has also been found that most of the interference situations are not due to the interfering signal being a DVB-T format, but that any significant signal amplitude in the passband of the filter causes interference. Therefore, MATV system distribution needs planning factors associated with the distribution of any signals near the main signal. The results are presented of a survey conducted among companies who install communal telecommunication infrastructures in Spain.     

Control and optimization of the divided wall column

The divided wall column (DWC) is, in terms of capital costs and energy savings, a promising alternative for separating ternary mixtures. Since its design was proposed, almost 50 years ago, many authors have addressed design considerations. Operation and control of the DWC have received much less attention. However, some works have been published recently. Preliminary results reported indicate that feedback diagonal control structures may be used to control the DWC. In this work, the study of feedback diagonal control strategies has been further extended to consider the DWC control design in detail. Different control structures have been systematically analyzed and compared under performance and robustness considerations. In order to study the effect of the energy optimization on the controllability of the DWC, a column at optimal nominal operating conditions is compared to a column under non-optimal operation. Finally, a complete control strategy is proposed. Linear analysis tools are used for the multiple input multiple output (MIMO) feedback control analysis, and simulations using a non-linear model are performed to study the non-linear behavior of the control systems.     

High efficiency and reusability of iridium complexes adsorbed in montmorillonite clay on catalytic hydrogenation of imines

Heterogenised homogeneous catalytic hydrogenation of aldimines by removable and reusable immobilised iridium complexes on montmorillonite clay. This revised version was published online in July 2006 with corrections to the Cover Date.     

Highly Diastereo‐ and Enantioselective Catalytic Domino Thia‐Michael/Aldol Reactions: Synthesis of Benzothiopyrans with Three Contiguous Stereocenters

Highly enantioselective organocatalytic domino thia‐Michael/aldol reactions between 2‐mercaptoacetophenone and α,β‐unsaturated aldehydes are presented. The reactions proceed with excellent chemo‐, diastereo‐ and enantioselectivity to give the corresponding benzothiopyran derivatives in high yields with up to >15:1 dr and 96 to >99 % ee.     

Advances and Perspectives in Dental Pulp Stem Cell Based Neuroregeneration Therapies

Human dental pulp stem cells (hDPSCs) are some of the most promising stem cell types for regenerative therapies given their ability to grow in the absence of serum and their realistic possibility to be used in autologous grafts. In this review, we describe the particular advantages of hDPSCs for neuroregenerative cell therapies. We thoroughly discuss the knowledge about their embryonic origin and characteristics of their postnatal niche, as well as the current status of cell culture protocols to maximize their multilineage differentiation potential, highlighting some common issues when assessing neuronal differentiation fates of hDPSCs. We also review the recent progress on neuroprotective and immunomodulatory capacity of hDPSCs and their secreted extracellular vesicles, as well as their combination with scaffold materials to improve their functional integration on the injured central nervous system (CNS) and peripheral nervous system (PNS). Finally, we offer some perspectives on the current and possible future applications of hDPSCs in neuroregenerative cell therapies.     

Genetic Contribution of Endometriosis to the Risk of Developing Hormone-Related Cancers

Endometriosis is a common gynecological disorder that has been associated with endometrial, breast and epithelial ovarian cancers in epidemiological studies. Since complex diseases are a result of multiple environmental and genetic factors, we hypothesized that the biological mechanism underlying their comorbidity might be explained, at least in part, by shared genetics. To assess their potential genetic relationship, we performed a two-sample mendelian randomization (2SMR) analysis on results from public genome-wide association studies (GWAS). This analysis confirmed previously reported genetic pleiotropy between endometriosis and endometrial cancer. We present robust evidence supporting a causal genetic association between endometriosis and ovarian cancer, particularly with the clear cell and endometrioid subtypes. Our study also identified genetic variants that could explain those associations, opening the door to further functional experiments. Overall, this work demonstrates the value of genomic analyses to support epidemiological data, and to identify targets of relevance in multiple disorders.     

Update on the Diagnostic Pitfalls of Autopsy and Post-Mortem Genetic Testing in Cardiomyopathies

Inherited cardiomyopathies are frequent causes of sudden cardiac death (SCD), especially in young patients. Despite at the autopsy they usually have distinctive microscopic and/or macroscopic diagnostic features, their phenotypes may be mild or ambiguous, possibly leading to misdiagnoses or missed diagnoses. In this review, the main differential diagnoses of hypertrophic cardiomyopathy (e.g., athlete’s heart, idiopathic left ventricular hypertrophy), arrhythmogenic cardiomyopathy (e.g., adipositas cordis, myocarditis) and dilated cardiomyopathy (e.g., acquired forms of dilated cardiomyopathy, left ventricular noncompaction) are discussed. Moreover, the diagnostic issues in SCD victims affected by phenotype-negative hypertrophic cardiomyopathy and the relationship between myocardial bridging and hypertrophic cardiomyopathy are analyzed. Finally, the applications/limits of virtopsy and post-mortem genetic testing in this field are discussed, with particular attention to the issues related to the assessment of the significance of the genetic variants.     

Evaluation of Floxuridine Oligonucleotide Conjugates Carrying Potential Enhancers of Cellular Uptake

Conjugation of small molecules such as lipids or receptor ligands to anti-cancer drugs has been used to improve their pharmacological properties. In this work, we studied the biological effects of several small-molecule enhancers into a short oligonucleotide made of five floxuridine units. Specifically, we studied adding cholesterol, palmitic acid, polyethyleneglycol (PEG 1000), folic acid and triantennary N-acetylgalactosamine (GalNAc) as potential enhancers of cellular uptake. As expected, all these molecules increased the internalization efficiency with different degrees depending on the cell line. The conjugates showed antiproliferative activity due to their metabolic activation by nuclease degradation generating floxuridine monophosphate. The cytotoxicity and apoptosis assays showed an increase in the anti-cancer activity of the conjugates related to the floxuridine oligomer, but this effect did not correlate with the internalization results. Palmitic and folic acid conjugates provide the highest antiproliferative activity without having the highest internalization results. On the contrary, cholesterol oligomers that were the best-internalized oligomers had poor antiproliferative activity, even worse than the unmodified floxuridine oligomer. Especially relevant is the effect induced by palmitic and folic acid derivatives generating the most active drugs. These results are of special interest for delivering other therapeutic oligonucleotides.