Process data visualisation with biplots

In this paper a modern methodology of biplots is introduced as a means for monitoring the behaviour of process systems. This sophisticated methodology allows for the projection of high-dimensional data to a low-dimensional subspace that can be visualised by a human operator. The projections are highly graphical in nature, and rich in information regarding variation in process variables, correlations among these variables, as well as class separation, taking into account the multivariate character of the data. Moreover, as is shown by way of two case studies, process disturbances can be visualised and explored quantitatively by superimposing alpha-bags on biplots. © 2005 Elsevier Ltd. All rights reserved.Articl

Biplot analysis of process systems

Plant data are collected in ever-increasing volumes in modern process industries and play an essential role in monitoring of product quality, control and continuous process improvement. In this paper a modern methodology of biplots is introduced as a means for analysing the behaviour of process systems by enhancing the aforementioned multivariate techniques. This sophisticated biplot methodology is highly graphical in nature and allows for the projection of high-dimensional data to a low-dimensional subspace leading to graphical displays for visualisation by a human operator. Biplots can be regarded as multivariate extensions of ordinary scatterplots where multidimensional sample data points are displayed simultaneously with information of all the variables concerned. In addition, two case studies demonstrate how class separation and multidimensional overlap can be quantitatively expressed by superimposing alpha-bags on biplots.Conference Pape

Examination of cucurbit[7]uril and its host-guest complexes by diffusion nuclear magnetic resonance

The self-diffusion of cucurbit[7]uril (CB[7]) and its host−guest complexes in D2O has been examined using pulsed gradient spin−echo nuclear magnetic resonance spectroscopy. CB[7] diffuses freely at a concentration of 2 mM with a diffusion coefficient (D) of 3.07 × 10-10 m2 s-1. At saturation (3.7 mM), CB[7] diffuses more slowly (D = 2.82 × 10-10 m2 s-1) indicating that it partially self-associates. At concentrations between 2 and 200 mM, CsCl has no effect on the diffusion coefficient of CB[7] (1 mM). Conversely, CB[7] (2 mM) significantly affects the diffusion of 133Cs+ (1 mM), decreasing its diffusion coefficient from 1.86 to 0.83 × 10-9 m2 s-1. Similar changes in the rate of diffusion of other alkali earth metal cations are observed upon the addition of CB[7]. The diffusion coefficient of 23Na+ changes from 1.26 to 0.90 × 10-9 m2 s-1 and 7Li+ changes from 3.40 to 3.07 × 10-9 m2 s-1. In most cases, encapsulation of a variety of inorganic and organic guests within CB[7] decreases their rates of diffusion in D2O. For instance, the diffusion coefficient of the dinuclear platinum complex trans-[{PtCl(NH3)2}2μ-dpzm]2+ (where dpzm is 4,4'-dipyrazolylmethane) decreases from 4.88 to 2.95 × 10-10 m2 s-1 upon encapsulation with an equimolar concentration of CB[7]

Polyamide platinum anticancer complexes designed to target specific DNA sequences

Two new platinum complexes, trans-chlorodiammine[N-(2-aminoethyl)-4-[4-(N-methylimidazole-2-carboxamido)-N-methylpyrrole-2-carboxamido]-N-methylpyrrole-2-carboxamide]platinum(II) chloride (DJ1953-2) and trans-chlorodiammine[N-(6-aminohexyl)-4-[4-(N-methylimidazole-2-carboxamido)-N-methylpyrrole-2-carboxamido]-N-methylpyrrole-2-carboxamide]platinum(II) chloride (DJ1953-6) have been synthesized as proof-of-concept molecules in the design of agents that can specifically target genes in DNA. Coordinate covalent binding to DNA was demonstrated with electrospray ionization mass spectrometry. Using circular dichroism, these complexes were found to show greater DNA binding affinity to the target sequence:  d(CATTGTCAGAC)2, than toward either d(GTCTGTCAATG)2, which contains different flanking sequences, or d(CATTGAGAGAC)2, which contains a double base pair mismatch sequence. DJ1953-2 unwinds the DNA helix by around 13°, but neither metal complex significantly affects the DNA melting temperature. Unlike simple DNA minor groove binders, DJ1953-2 is able to inhibit, in vitro, RNA synthesis. The cytotoxicity of both metal complexes in the L1210 murine leukaemia cell line was also determined, with DJ1953-6 (34 μM) more active than DJ1953-2 (>50 μM). These results demonstrate the potential of polyamide platinum complexes and provide the structural basis for designer agents that are able to recognize biologically relevant sequences and prevent DNA transcription and replicatio

Anionic PAMAM dendrimers as drug delivery vehicles for transition metal-based anticancer drugs

The use of anionic half-generation poly(amidoamine) dendrimers as drug delivery vehicles for [Pt(S,S-dach)(5,6-Me2phen)]2+ (56MESS) (where S,S-dach = 1S,2S-diaminocyclohexane; 5,6-Me2phen = 5,6-dimethyl-1,10-phenanthroline) and [{Δ,Δ-Ru(phen)2}2(μ-bb7)]4+ (Rubb7) (where phen = 1,10-phenanthroline; bb7 = 1,7-bis[4-(4′-methyl-2,2′-bipyridyl)heptane]) has been studied by nuclear magnetic resonance spectroscopy. From one- and two-dimensional 1H NMR spectra both 56MESS and Rubb7 were found to bind to the surface of generation 3.5, 4.5, 5.5 and 6.5 dendrimers through electrostatic interactions. The higher charge and larger size of Rubb7 resulted in stronger binding to all dendrimer generations (Kb 2 × 105 M−1) compared with 56MESS (Kb 1 × 104 M−1). Interestingly, there appeared to be no observable trend between dendrimer size and binding constant strength. The size of the free and 56MESS-bound dendrimers were examined using pulsed-gradient spin-echo NMR. The dendrimers ranged in hydrodynamic diameter from 11 to 20 nm and in all cases were larger than their corresponding full-generation dendrimer. Upon the addition of 56MESS the diameter of the dendrimers increased, consistent with surface binding

COVID-19 first lockdown as a window into language acquisition: Associations between caregiver-child activities and vocabulary gains

The COVID-19 pandemic, and the resulting closure of daycare centers worldwide, led to unprecedented changes in children's learning environments. This period of increased time at home with caregivers, with limited access to external sources (e.g., daycares) provides a unique opportunity to examine the associations between the caregiver-child activities and children's language development. The vocabularies of 1742 children aged8-36 months across 13 countries and 12 languages were evaluated at the beginning and end of the first lockdown period in their respective countries(from March to September 2020). Children who had less passive screen exposure and whose caregivers read more to them showed larger gains in vocabulary development during lockdown, after controlling for SES and other caregiver-child activities. Children also gained more words than expected (based on normative data) during lockdown; either caregivers were more aware of their child’s development or vocabulary development benefited from intense caregiver-child interaction during lockdown

Acute lymphoblastic leukaemia among Spanish children and mothers' occupation: a case-control study.

STUDY OBJECTIVE--The aim was to investigate the association between mothers' occupational exposure during pregnancy and the incidence of acute lymphoblastic leukaemia in children. DESIGN--The study was a case-control investigation. A face to face interview was used to assess exposures at work and relevant confounding variables. SETTING--The study was community based and was carried out in five provinces of Spain. SUBJECTS--128 cases less than 15 years of age were interviewed (91% of those eligible). Controls (one for each case) were chosen from the census lists and were matched on year of birth, sex and municipality. MEASUREMENTS AND MAIN RESULTS--Children of mothers working at home had a relative risk (RR) of 7.0 (95% CI = 1.59-30.79) of developing acute lymphoblastic leukaemia. Exposure to organic dust was associated with a RR of 5.5 (95% CI = 1.21-24.8). There was a statistically significant interaction between exposure to organic dust and working at home. The majority of women working at home were hired by local industries to sew different types of tissues (cotton, wool, synthetic fibres) on a machine. CONCLUSION--A similar association has not been reported before: if confirmed, this finding may suggest a new health concern