bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ten challenges in improving quality in healthcare: lessons from the Health Foundation's programme evaluations and relevant literature: Table 1
Authors: Dixon-Woods Mary , McNicol Sarah , Martin Graham 
Published: April 2012

BackgroundFormal evaluations of programmes are an important source of learning about the challenges faced in improving quality in healthcare and how they can be addressed. The authors aimed to integrate lessons from evaluations of the Health Foundation's improvement programmes with relevant literature.MethodsThe authors analysed evaluation reports relating to five Health Foundation improvement programmes using a form of ‘best fit’ synthesis, where a pre-existing framework was used for initial coding and then updated in response to the emerging analysis. A rapid narrative review of relevant literature was also undertaken.ResultsThe authors identified ten key challenges: convincing people that there is a problem that is relevant to them; convincing them that the solution chosen is the right one; getting data collection and monitoring systems right; excess ambitions and ‘projectness’; organisational cultures, capacities and contexts; tribalism and lack of staff engagement; leadership; incentivising participation and ‘hard edges’; securing sustainability; and risk of unintended consequences. The authors identified a range of tactics that may be used to respond to these challenges.DiscussionSecuring improvement may be hard and slow and faces many challenges. Formal evaluations assist in recognising the nature of these challenges and help in addressing them.
AggressiveHelicobacter pylori-negative peptic ulceration as the initial manifestation of Crohn's disease
Authors: Callaghan James , Brown Sarah , Battcock Tim , Parry Sally , Snook Jonathon 
Published: May 2012

Peptic ulceration is a recognised feature of Crohn's disease, but the characteristics of this manifestation are rather poorly described. Furthermore, most reports in the literature relate to ulcer disease in cases of established Crohn's disease.The authors report a series of four cases in which the diagnosis of Crohn's disease was preceded by peptic ulceration. Potential confounding factors were as far as possible excluded, implying a true association. Characteristics of the ulcer disease included (1) a multifocal distribution, (2)Helicobacter pylorinegativity and (3) an unusually aggressive clinical course despite proton pump inhibitor therapy, necessitating endoscopic or surgical intervention in three cases.Crohn's-related peptic ulceration is a relatively common manifestation which may precede the diagnosis of Crohn's disease itself. Recognition of the underlying diagnosis may be hampered by non-specific histology, but is important in view of the aggressive course of the ulceration, which may respond to medical therapy for Crohn's disease.
Theoretical studies on clusters of carbonate with carbon dioxide, CO31–/2–(CO2)n, forn= 1–5 — Comparison of carbonate clusters with sulfate clusters
Authors: Grein Friedrich , Chevrier Daniel M. 
Published: May 2012

Density functional theory (DFT) calculations were performed on the geometries and energies of CO31–/2–(CO2)nclusters with n = 1–5. For small clusters (n = 1 or 2), coupled cluster energies were obtained. Up to three CO2molecules are bound covalently to the dianion. Only weak electrostatic bonds were found in the monoanions. Calculated binding energies for the monoanions are in reasonable agreement with experimental values. The calculated adiabatic electron detachment energy for the dianion is –0.07 eV at n = 5, indicating that at least six CO2molecules will have to be added to CO32–before the dianionic cluster becomes, in the gas phase, more stable than the monoanionic one. In comparison, for sulfate – carbon dioxide clusters, stabilization occurs at n = 2. Carbonate clusters are compared with sulfate clusters for three solvent molecules: CO2, SO2, and H2O. Carbonate clusters have larger binding energies than sulfate clusters. For a given dianion, binding energies are largest for SO2and smallest for H2O. However, in all cases, stabilization of the carbonate dianion by clustering is more difficult to achieve than stabilization of the sulfate dianion.
Distinctive heat-shock response of bioleaching microorganismAcidithiobacillus ferrooxidansobserved using genome-wide microarray
Authors: Yin Huaqun , Tang Min , Zhou Zhijun , Fu Xian , Shen Li , Liang Yili , Li Qian , Liu Hongwei , Liu Xueduan 
Published: May 2012

Temperature plays an important role in the heap bioleaching. The maldistribution of ventilation in the heap leads to local hyperthermia, which does exert a tremendous stress on bioleaching microbes. In this study, the genome-wide expression profiles of Acidithiobacillus ferrooxidans at 40 °C were detected using the microarray. The results showed that some classic proteases like Lon and small heat-shock proteins were not induced, and heat-inducible membrane proteins were suggested to be under the control of σE. Moreover, expression changes of energy metabolism are noteworthy, which is different from that in heterotrophic bacteria upon heat stress. The induced enzymes catalyzed the central carbon metabolism pathway that might mainly provide precursors of amino acids for protein synthesis. These results will deepen the understanding of the mechanisms of heat-shock response on autotrophic bacteria.
Production of natural folates by lactic acid bacteria starter cultures isolated from artisanal Argentinean yogurts
Authors: Laiño Jonathan Emiliano , LeBlanc Jean Guy , Savoy de Giori Graciela 
Published: May 2012

Folate is a B-group vitamin that cannot be synthesized by humans and must be obtained exogenously. Although some species of lactic acid bacteria (LAB) can produce folates, little is known about the production of this vitamin by yogurt starter cultures. Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus strains were isolated from artisanal Argentinean yogurts and were grown in folate-free culture medium (FACM) and nonfat milk after which intracellular and extracellular folate production were evaluated. From the initial 92 isolated LAB strains, 4 L. delbrueckii subsp. bulgaricus and 32 S. thermophilus were able to grow in the absence of folate. Lactobacillus delbrueckii subsp. bulgaricus CRL 863 and S. thermophilus CRL 415 and CRL 803 produced the highest extracellular folate levels (from 22.3 to 135 µg/L) in FACM. In nonfat milk, these strains were able to increase the initial folate concentrations by almost 190%. This is the first report where native strains of L. delbrueckii subsp. bulgaricus were shown to produce natural folate. The LAB strains identified in this study could be used in developing novel fermented products bio-enriched in natural folates that could in turn be used as an alternative to fortification with the controversial synthetic chemical folic acid.
Raman spectroscopic study on the subpicosecond dynamics in calf-thymus DNA, upon lowering the pH and in the presence of Mn2+ions
Authors: Muntean Cristina M. , Bratu Ioan 
Published: April 2012

In this paper the Raman total half bandwidths of calf-thymus DNA vibrations have been measured as a function of pH (3.45–6.4), in the presence of Mn2+ions, respectively. The dependencies of the half bandwidths and of the global relaxation times, on DNA molecular subgroup structure and on pH, are reported. It is shown that changes in the subpicosecond dynamics of molecular subgroups in calf-thymus DNA can be monitored with Raman spectroscopy.Particularly, the Raman band parameters for the vibrations at 728 cm–1(dA), 787 cm–1(dC), 1093 cm–1(PO2–), 1376 cm–1(dA, dG, dT, dC), 1489 cm–1(dG, dA) and 1578 cm–1(dG, dA) of MnDNA complexes, at reduced and low pH values, are presented. In our study, the full widths at half-maximum (FWHM) of the bands in calf-thymus DNA are typically in the wavenumber range from 11 to 27 cm–1. It can be observed that the molecular relaxation processes studied in this work, have a global relaxation time smaller than 0.965 ps and larger than 0.393 ps. The limit values are characteristic for dA and dC residues, respectively (vibrations at 728 and 787 cm–1).Low pH-induced melting of double helical structure in calf-thymus DNA, in the presence of Mn2+ions, results for some bands in smaller global relaxation times, and larger bandwidths, respectively, as a consequence of the increased interaction of the base moieties with the solvent molecules. This behaviour is most evident for the bands at 787 cm–1up to pH 3.8, at 1578 cm–1up to pH 3.45 and is partially confirmed for the DNA backbone PO2–symmetric stretching vibration at 1093 cm–1.The fastest molecular dynamics was obtained for the adenine band at 728 cm–1in the pH interval 3.45–3.8 (global relaxation time 0.885 ps), for the cytosine ring breathing mode near 787 cm–1around the pH 3.8 (global relaxation time 0.393 ps), for the band at 1093 cm–1in the pH interval 3.8–4.4 (global relaxation time 0.518 ps) and for the vibration near 1578 cm–1at pH 3.45 (global relaxation time 0.544 ps).A comparison between different time scales of the vibrational energy transfer processes, characterizing the protonated MnDNA structural subgroups has been given.We have found that metal ion's type and concentration are modulators for the (sub)picosecond dynamics of protonated DNA molecular subgroups.
A transvaginal probe for near infrared spectroscopic monitoring of the bladder detrusor muscle and urethral sphincter
Authors: Shadgan Babak , Stothers Lynn , Macnab Andrew 
Published: April 2012

The majority ofin vivoapplications of near infrared spectroscopic (NIRS) monitoring use transcutaneous optode placement over the tissue of interest. Invasive application of optodes is occasionally described for monitoring tissue too deep for transcutaneous study, principally in animal models, but sometimes in humans. Invasive fibre-optic probes have been developed for a range of other spectroscopic applications including somein vivo. We describe the design and feasibility testing in a human subject of a vaginal probe to extend the scope of recently developed techniques for NIRS monitoring in urology.Design criteria included: use of optodes and cables with dimensions compatible with appropriate overall probe size; dual channel capability (for simultaneous monitoring of bladder wall and urethral sphincter); secure interoptode separation at correct distance for required penetration; ease of insertion, orientation and avoidance of movement artifact.Components were obtained that met design criteria and allowed use of the probe connected to a commercial NIRS instrument. Iterative development established optimal interoptode distance and secure positioning of a probe that could be housed forin vivostudy within a disposable vaginal speculum.The feasibility of monitoring changes in chromophore concentration in the bladder detrusor and urethral sphincter using this intravaginal probe was evident from four separate studies during voiding and a series of physiologic events (cough, Valsalva and Kiegel contractions) in a healthy female volunteer. This small series suggests that reproducible data free of movement artifact, with consistent patterns and magnitudes of chromophore change can be obtained with the probe designed.
Time-resolved step scan FTIR spectroscopy and DFT investigation on triplet formation in peridinin–chlorophyll-a–protein from Amphidinium carterae at low temperature
Authors: Mezzetti Alberto , Spezia Riccardo 
Published: April 2012

We have used time-resolved step-scan FTIR spectroscopy to investigate the process of triplet formation in the peridinin–chlorophyll-a–protein (PCP) at 100 K. Results have led to the identification of possible marker bands for peridinin (Per) and3Per. Band assignment has been carried out performing a DFT investigation on Per,3Per and on model molecules. The main spectral feature is a couple of bands at 1746 (negative) and 1719 (positive) cm–1. The assignment of these two bands to the lactonic C═O of Per in (respectively) its fundamental S0 and tripletT1state is based on: (1) comparison with FTIR spectra of isolated Per in literature; (2) good agreement with DFT calculations for Per and3Per; (3) the downshift of the band upon triplet formation as predicted by DFT calculations in Per and similar lactonic systems; (4) the kinetic of band disappearance, in agreement with literature data. Another possible band for Per in its fundamental state has been identified at 1523 cm–1.The results are in overall agreement with a recent step-scan FTIR study on PCP at 298 K (Alexandre et al.,Biophys. J. 93 (2007), 2118–2128) even though some small discrepancies emerge, probably related to the different temperature at which experiments were carried out. Further DFT calculations have been performed to rationalise these spectral discrepancies. From a methodological point of view, the work demonstrates the potential of a combined step-scan FTIR/DFT approach in the study of photophysical processes in proteins. Furthermore, it has been shown that, when small differential IR signals are concerned, nagging photothermal effects can interfere and can possibly lead to misleading interpretations.
Hydration structure analysis of lysozyme amyloid fibrils by thermally stimulated depolarization currents (TSDC) technique
Authors: Bridelli Maria Grazia , Capelletti Rosanna 
Published: April 2012

Thermally stimulated depolarization currents technique has been employed to investigate the conformation of hen egg white lysozyme in native and amyloid form, in the state of powder at very low hydration level. The technique, able to detect the current generated by thermally activated reorientation of water dipoles previously oriented by an electric field, exploits H2O dipoles, belonging to the solvation shell, as a probe to gain information on the protein conformation.Large differences are detected between the TSDC spectra related to the two different protein conformations, for what concerns the number and position of the main peaks, the native form displaying two peaks, atTM=175 K and atTM=297 K, and the amyloid one, only one at intermediate temperature (TM=235 K). The spectra have been compared with those monitored for poly-L-lysine (MW 80400), as received and prepared in different ways, i.e.α-helix,β-sheet, and coil conformation, respectively. The poly-L-lysine spectra show specific features that can be attributed to water texture around the secondary structure adopted by the macromolecule: the results stress how TSDC technique is a tool of great potential value in the conformational analysis of proteins.
Infrared investigation of hard human teeth tissues exposed to various doses of ionizing radiation from the 1986 Chernobyl accident
Authors: Darchuk L. A. , Zaverbna L. V. , Bebeshko V. G. , Worobiec A. , Stefaniak E. A. , Grieken R. Van 
Published: April 2012

Infrared spectroscopy (IR) was applied to study changes in solid teeth tissues of persons exposed to low (0.12–0.20 Gy) and high (0.5–1.7 Gy) doses of ionizing radiation during their work in the Chernobyl zone after the accident. Changes in the inorganic and organic matrix of teeth were noted for both high and low radiation doses. The obtained results demonstrated that high doses of radiation lead to imbalance between phosphate–carbonate phases level (because of increasing of CO32−content) and accumulation of soluble phosphates in the mineral part of the teeth. These changes have an effect on dental matrix strength. Low doses of radiation do not induce appreciable negative changes in the mineral part of all tooth tissues but lead to changes in organic matrix of teeth (in collagen).The present results demonstrated that pathological effect of radiation touches upon all dental tissue and obviously all bone systems of irradiated people.
Molecular relaxation processes in calf-thymus DNA, in the presence of Mn2+and Na+ions: A Raman spectroscopic study
Authors: Muntean Cristina M. , Bratu Ioan 
Published: April 2012

In this paper the Raman total half bandwidths of calf-thymus DNA vibrations have been measured as a function of Mn2+ion concentration (0–600 mM), in the presence of two concentrations of Na+cations, respectively. The dependencies of the half bandwidths and of the global relaxation times on DNA molecular subgroup structure, on Mn2+and Na+ions concentrations, respectively, are reported. It is shown that changes in the (sub)picosecond dynamics of molecular subgroups in calf-thymus DNA can be monitored with Raman spectroscopy.In this study the Raman band parameters for the vibrations at 729 cm-1(dA), 787 cm-1(dC), 1094 cm-1(PO2-), 1376 cm-1(dA, dG, dT, dC), 1489 cm-1(dG, dA) and 1578 cm-1(dG, dA) of calf thymus DNA are presented. The full-widths at half-height (FWHH) of the bands in calf-thymus DNA are typically in the wavenumber range from 9 to 33.5 cm-1. It can be observed that the molecular relaxation processes studied in this work, have a global relaxation time smaller than 1.179 ps and larger than 0.317 ps.Mn2+-induced DNA structural changes result for the vibrations at 729 cm-1and 787 cm-1in smaller global relaxation times, and larger half bandwidths, respectively, as compared to the starting value of 0 mM Mn2+. The vibrational energy transfer processes of these two subgroups (dA, dC), respectively, are slower in the case of DNA samples at 10 mM NaCl, as compared to the corresponding DNA samples at 150 mM NaCl. However, the behaviour of the global relaxation times characteristic to the bands at 729 and 787 cm-1is similar with respect to manganese(II) ions concentration, in the case of the two values of Na+ions content, respectively.On the contrary, the molecular dynamics is slower for the base vibrations at 1376, 1489 and 1578 cm-1, in the case of DNA samples at 150 mM NaCl, as compared to the corresponding samples at lower Na+concentration, in almost all Mn2+ions concentration range. The molecular relaxation processes in these three cases, respectively, are quite different for the corresponding samples with different Na+ions content, upon increasing divalent manganese ions concentration.The molecular dynamics characterizing the band near 1094 cm-1of the DNA backbone PO2-symmetric stretching vibration is faster upon increasing the Mn2+ions concentration between 0–600 mM and seems not to be influenced by the Na+ions content, specific to our experimental conditions.
Lymph node pathology using optical spectroscopy in cancer diagnostics
Authors: Isabelle M. , Stone N. , Barr H. , Vipond M. , Shepherd N. , Rogers K. 
Published: April 2012

Raman and infrared spectroscopy are optical spectroscopic techniques that use light scattering (Raman) and light absorption (infrared) to probe the vibrational energy levels of molecules in tissue samples. Using these techniques, one can gain an insight into the biochemical composition of cells and tissues by looking at the spectra produced and comparing them with spectra obtained from standards such as proteins, nucleic acids, lipids and carbohydrates. As a result of optical spectroscopy being able to measure these biochemical changes, diagnosis of cancer could take place faster than current diagnostic methods, assisting and offering pathologists and cytologists a novel technology in cancer screening and diagnosis.The purpose of this study is to use both spectroscopic techniques, in combination with multivariate statistical analysis tools, to analyze some of the major biochemical and morphological changes taking place during carcinogenesis and metastasis in lymph nodes and to develop a predictive model to correctly differentiate cancerous from benign lymph nodes taken from oesophageal cancer patients.The results of this study showed that Raman and infrared spectroscopy managed to correctly differentiate between cancerous and benign oesophageal lymph nodes with a training performance greater than 94% using principal component analysis (PCA)-fed linear discriminant analysis (LDA). Cancerous nodes had higher nucleic acid but lower lipid and carbohydrate content compared to benign nodes which is indicative of increased cell proliferation and loss of differentiation.With better understanding of the molecular mechanisms of carcinogenesis and metastasis together with use of multivariate statistical analysis tools, these spectroscopic studies will provide a platform for future development of real-time (in surgery) non-invasive diagnostic tools in medical research.
FT-Raman signatures of genomic DNA from plant tissues
Authors: Muntean Cristina M. , Halmagyi Adela , Puia Mircea D. , Pavel Ioana 
Published: April 2012

The vibrational spectra of eight genomic DNAs from leaf tissues (sword fern (Nephrolepis exaltataL.), chrysanthemum (Dendranthema grandifloraRamat.), redwood (Sequoia sempervirensD. Don. Endl.), orchids (Cymbidium × hybrida), common sundew (Drosera rotundifoliaL.), potato (Solanum tuberosumL.) and scopolia (Scopolia carniolicaJacq.)) have been analyzed using FT-Raman spectroscopy, in the wavenumber range 500–1800 cm–1.FT-Raman signatures, spectroscopic assignments and structural interpretations for these plant genomic DNAs are reported. Spectral differences among two genomic DNAs, independently extracted from chrysanthemum leaves, are to be observed between 1000–1200 cm–1. Besides, similarities in the FT-Raman spectra of genomic DNAs from potato and scopolia leaves, respectively, have been found. This might be explained by their belonging to the same family (Solanaceae). Other spectral differences among genomic plant DNAs have also been observed.These findings demonstrate that Raman spectroscopy may be exploited to distinguish different plant genomic DNAs.The present study provides a basis for future use of Raman spectroscopy to analyze specific plant DNA–ligand interactions or DNA structural changes induced by plants' stress conditions associated with their natural environment.
Zn2+–DNA interactions in aqueous systems: A Raman spectroscopic study
Authors: Muntean Cristina M. , Nalpantidis Konstantinos , Feldmann Ingo , Deckert Volker 
Published: April 2012

The influence of Zn2+ions on the structure of natural calf thymus DNA was studied by Raman spectroscopy. Measurements were done at room temperature and pH 6.2±0.1, in the presence of 10 mM Na+, and of Zn2+in a concentration range varying between 0 and 250 mM, respectively. No condensation of DNA was observed.As judging from the marker bands near 681 cm−1(dG), 729 cm−1(dA), 752 cm−1(dT), and 787 cm−1(dC, dT) altered nucleoside conformations in these residues are supposed to occur, in different intervals of Zn2+ions concentration. Changes in the conformational marker centered around 835 cm−1, upon Zn2+binding to DNA, were detected. Binding of zinc(II) ions to the charged phosphate groups of DNA, stabilizing the double helical structure, is indicated in the spectra. We have found that binding of metal ions at N3 of cytosine takes place at zinc(II) concentrations between 150–250 mM and interaction of Zn2+ions with adenine is observed in a concentration range from 10 to 250 mM. Binding of zinc(II) ions to N7 of guanine and, possibly, in a lesser extent to adenine was also observed as indicated by the Raman marker bands near 1490 and 1581 cm−1. There is no intensity change of the band at 1668 cm−1, suggesting no change in their base pairing and no change induced in the structure of water by Zn2+cations. No evidence for DNA melting was identified.