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A pore-expanded supramolecular organic framework and its enrichment of photosensitizers and catalysts for visible-light-induced hydrogen production
A pore-expanded three-dimensional supramolecular organic framework SOF-bpb, with a previously unattained aperture size of 3.6 nm, has been constructed in water from the co-Assembly of cucurbit[8]uril (CB[8]) and a tetraphenylmethane-cored 1,4-bis(pyridin-4-yl)-benzene-Appended building block M1. The periodicity of SOF-bpb in water and in the solid state has been confirmed using synchrotron X-ray scattering and diffraction experiments. SOF-bpb can adsorb anionic and neutral Ru complex photosensitizers and anionic Wells-Dawson-Type and Keggin-Type polyoxometalates (POMs). The adsorption leads to an important enrichment effect, which remarkably increases the catalytic efficiency of the Ru complex-POM systems for visible light-induced reduction of protons to produce H . The expanded aperture of SOF-bpb also facilitates light absorption of the adsorbed Ru complex photosensitizers and electron transfer between excited complexes and the POM catalysts, leading to enhanced photocatalytic activities as compared with the prototypical SOF that has an aperture size of 2.1 nm. 2+ 2+ 2+
How liquid are banks : some evidence from the United Kingdom
This paper uses quantitative balance sheet liquidity analysis, based upon modified versions of the BCBS 1 and Moody’s 2 models, to provide indicators which would alarm the UK banks’ short and long-term liquidity positions respectively. These information will also underpin other research related liquidity risk to banks’ lending and performance. Our framework accurately reflect UK banks’ liquidity positions under both normal and stress scenarios based on the consistent accounting information under IFRS. It has significant contribution on Basel III liquidity ratios calculation. The study also presents fundamental financial information to facilitate analysis of banks’ business models and funding strategies.
Using data for the period 2005-2010, we provide evidence that there have been variable liquidity strains across the UK banks in our sample. The estimated results show that Barclays Bank was the only bank to maintain a healthy short-term liquidity position throughout the sample period; while HSBC remained liquid in the short term, in both normal and stress conditions, except in 2008 and 2010. RBS, meanwhile, maintained healthy long-term liquidity positions from 2008 after receiving government injections of capital. And Santander UK was also able to post healthy long-term liquidity positions, except in 2009. However, the other four banks, the Bank of Scotland, Lloyds TSB, Natwest, and Standard Chartered,
proved illiquid, on both a short-term and long-term basis, throughout the six-year period, with Natwest being by far the worst performer
Regional differences in APD restitution can initiate wavebreak and re-entry in cardiac tissue: A computational study
Background
Regional differences in action potential duration (APD) restitution in the heart favour arrhythmias, but the mechanism is not well understood.
Methods
We simulated a 150 × 150 mm 2D sheet of cardiac ventricular tissue using a simplified computational model. We investigated wavebreak and re-entry initiated by an S1S2S3 stimulus protocol in tissue sheets with two regions, each with different APD restitution. The two regions had a different APD at short diastolic interval (DI), but similar APD at long DI. Simulations were performed twice; once with both regions having steep (slope > 1), and once with both regions having flat (slope < 1) APD restitution.
Results
Wavebreak and re-entry were readily initiated using the S1S2S3 protocol in tissue sheets with two regions having different APD restitution properties. Initiation occurred irrespective of whether the APD restitution slopes were steep or flat. With steep APD restitution, the range of S2S3 intervals resulting in wavebreak increased from 1 ms with S1S2 of 250 ms, to 75 ms (S1S2 180 ms). With flat APD restitution, the range of S2S3 intervals resulting in wavebreak increased from 1 ms (S1S2 250 ms), to 21 ms (S1S2 340 ms) and then 11 ms (S1S2 400 ms).
Conclusion
Regional differences in APD restitution are an arrhythmogenic substrate that can be concealed at normal heart rates. A premature stimulus produces regional differences in repolarisation, and a further premature stimulus can then result in wavebreak and initiate re-entry. This mechanism for initiating re-entry is independent of the steepness of the APD restitution curve
Gene and protein expression of glucose transporter 1 and glucose transporter 3 in human laryngeal cancer—the relationship with regulatory hypoxia-inducible factor-1α expression, tumor invasiveness, and patient prognosis
Increased glucose uptake mediated by glucose
transporters and reliance on glycolysis are common features
of malignant cells. Hypoxia-inducible factor-1α supports the
adaptation of hypoxic cells by inducing genes related to
glucose metabolism. The contribution of glucose transporter
(GLUT) and hypoxia-inducible factor-1α (HIF-1α) activity to
tumor behavior and their prognostic value in head and neck
cancers remains unclear. The aim of this study was to examine
the predictive value of GLUT1, GLUT3, and HIF-1α messenger
RNA (mRNA)/protein expression as markers of tumor
aggressiveness and prognosis in laryngeal cancer. The level of
hypoxia/metabolic marker genes was determined in 106 squamous
cell laryngeal cancer (SCC) and 73 noncancerous
matched mucosa (NCM) controls using quantitative realtime
PCR. The related protein levels were analyzed by
Western blot. Positive expression of SLC2A1, SLC2A3, and
HIF-1α genes was noted in 83.9, 82.1, and 71.7 % of SCC
specimens and in 34.4, 59.4, and 62.5 % of laryngeal cancer
samples. Higher levels of mRNA/protein for GLUT1 and
HIF-1α were noted in SCC compared to NCM (p<0.05).
SLC2A1 was found to have a positive relationship with grade,
tumor front grading (TFG) score, and depth and mode of
invasion (p<0.05). SLC2A3 was related to grade and invasion
type (p<0.05). There were also relationships of HIF-1α with
pTNM, TFG scale, invasion depth and mode, tumor recurrences,
and overall survival (p<0.05). In addition, more advanced
tumors were found to be more likely to demonstrate
positive expression of these proteins. In conclusion, the
hypoxia/metabolic markers studied could be used as molecular
markers of tumor invasiveness in laryngeal cancer.This work was supported, in part, by the statutory
fund of the Department of Cytobiochemistry, University of Łódź, Poland
(506/811), and by grant fromtheNational Science Council, Poland (N403
043 32/2326)
Serious fungal infections in Portugal
There is a lack of knowledge on the epidemiology of fungal infections worldwide because there are no reporting obligations. The aim of this study was to estimate the burden of fungal disease in Portugal as part of a global fungal burden project. Most published epidemiology papers reporting fungal infection rates from Portugal were identified. Where no data existed, specific populations at risk and fungal infection frequencies in those populations were used in order to estimate national incidence or prevalence, depending on the condition. An estimated 1,510,391 persons develop a skin or nail fungal infection each year. The second most common fungal infection in Portugal is recurrent vulvovaginal candidiasis, with an estimated 150,700 women (15-50 years of age) suffering from it every year. In human immunodeficiency virus (HIV)-infected people, oral or oesophageal candidiasis rates were estimated to be 19.5 and 16.8/100,000, respectively. Candidaemia affects 2.19/100,000 patients, in a total of 231 cases nationally. Invasive aspergillosis is less common than in other countries as chronic obstructive pulmonary disease (COPD) is uncommon in Portugal, a total of 240 cases annually. The estimated prevalence of chronic pulmonary aspergillosis after tuberculosis (TB) is 194 cases, whereas its prevalence for all underlying pulmonary conditions was 776 patients. Asthma is common (10% in adults) and we estimate 16,614 and 12,600 people with severe asthma with fungal sensitisation and allergic bronchopulmonary aspergillosis, respectively. Sixty-five patients develop Pneumocystis pneumonia in acquired immune deficiency syndrome (AIDS) and 13 develop cryptococcosis. Overall, we estimate a total number of 1,695,514 fungal infections starting each year in Portugal.info:eu-repo/semantics/publishedVersio
A bi-directional relationship between obesity and health-related quality of life : evidence from the longitudinal AusDiab study
Objective: To assess the prospective relationship between obesity and health-related quality of life, including a novel assessment of the impact of health-related quality of life on weight gain.Design and setting: Longitudinal, national, population-based Australian Diabetes, Obesity and Lifestyle (AusDiab) study, with surveys conducted in 1999/2000 and 2004/2005.Participants: A total of 5985 men and women aged 25 years at study entry.Main outcome measure(s): At both time points, height, weight and waist circumference were measured and self-report data on health-related quality of life from the SF-36 questionnaire were obtained. Cross-sectional and bi-directional, prospective associations between obesity categories and health-related quality of life were assessed.Results: Higher body mass index (BMI) at baseline was associated with deterioration in health-related quality of life over 5 years for seven of the eight health-related quality of life domains in women (all P0.01, with the exception of mental health, P>0.05), and six out of eight in men (all P<0.05, with the exception of role-emotional, P=0.055, and mental health, P>0.05). Each of the quality-of-life domains related to mental health as well as the mental component summary were inversely associated with BMI change (all P<0.0001 for women and P0.01 for men), with the exception of vitality, which was significant in women only (P=0.008). For the physical domains, change in BMI was inversely associated with baseline general health in women only (P=0.023).Conclusions: Obesity was associated with a deterioration in health-related quality of life (including both physical and mental health domains) in this cohort of Australian adults followed over 5 years. Health-related quality of life was also a predictor of weight gain over 5 years, indicating a bi-directional association between obesity and health-related quality of life. The identification of those with poor health-related quality of life may be important in assessing the risk of future weight gain, and a focus on health-related quality of life may be beneficial in weight management strategies.<br /
Insights from Amphioxus into the Evolution of Vertebrate Cartilage
Central to the story of vertebrate evolution is the origin of the vertebrate head, a problem difficult to approach using paleontology and comparative morphology due to a lack of unambiguous intermediate forms. Embryologically, much of the vertebrate head is derived from two ectodermal tissues, the neural crest and cranial placodes. Recent work in protochordates suggests the first chordates possessed migratory neural tube cells with some features of neural crest cells. However, it is unclear how and when these cells acquired the ability to form cellular cartilage, a cell type unique to vertebrates. It has been variously proposed that the neural crest acquired chondrogenic ability by recruiting proto-chondrogenic gene programs deployed in the neural tube, pharynx, and notochord. To test these hypotheses we examined the expression of 11 amphioxus orthologs of genes involved in neural crest chondrogenesis. Consistent with cellular cartilage as a vertebrate novelty, we find that no single amphioxus tissue co-expresses all or most of these genes. However, most are variously co-expressed in mesodermal derivatives. Our results suggest that neural crest-derived cartilage evolved by serial cooption of genes which functioned primitively in mesoderm
N-type graphene induced by dissociative H-2 adsorption at room temperature
Studies of the interaction between hydrogen and graphene have been increasingly required due to the indispensable modulation of the electronic structure of graphene for device applications and the possibility of using graphene as a hydrogen storage material. Here, we report on the behaviour of molecular hydrogen on graphene using the gate voltage-dependent resistance of single-, bi-, and multi-layer graphene sheets as a function of H-2 gas pressure up to 24 bar from 300 K to 345 K. Upon H-2 exposure, the charge neutrality point shifts toward the negative gate voltage region, indicating n-type doping, and distinct Raman signature changes, increases in the interlayer distance of multi-layer graphene, and a decrease in the d-spacing occur, as determined by TEM. These results demonstrate the occurrence of dissociative H-2 adsorption due to the existence of vacancy defects on graphene.open12
JLab Measurements of the 3He Form Factors at Large Momentum Transfers
The charge and magnetic form factors, FC and FM, of 3He have been extracted
in the kinematic range 25 fm-2 < Q2 < 61 fm-2 from elastic electron scattering
by detecting 3He recoil nuclei and electrons in coincidence with the High
Resolution Spectrometers of the Hall A Facility at Jefferson Lab. The
measurements are indicative of a second diffraction minimum for the magnetic
form factor, which was predicted in the Q2 range of this experiment, and of a
continuing diffractive structure for the charge form factor. The data are in
qualitative agreement with theoretical calculations based on realistic
interactions and accurate methods to solve the three-body nuclear problem
Measurement of the inclusive and dijet cross-sections of b-jets in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector
The inclusive and dijet production cross-sections have been measured for jets
containing b-hadrons (b-jets) in proton-proton collisions at a centre-of-mass
energy of sqrt(s) = 7 TeV, using the ATLAS detector at the LHC. The
measurements use data corresponding to an integrated luminosity of 34 pb^-1.
The b-jets are identified using either a lifetime-based method, where secondary
decay vertices of b-hadrons in jets are reconstructed using information from
the tracking detectors, or a muon-based method where the presence of a muon is
used to identify semileptonic decays of b-hadrons inside jets. The inclusive
b-jet cross-section is measured as a function of transverse momentum in the
range 20 < pT < 400 GeV and rapidity in the range |y| < 2.1. The bbbar-dijet
cross-section is measured as a function of the dijet invariant mass in the
range 110 < m_jj < 760 GeV, the azimuthal angle difference between the two jets
and the angular variable chi in two dijet mass regions. The results are
compared with next-to-leading-order QCD predictions. Good agreement is observed
between the measured cross-sections and the predictions obtained using POWHEG +
Pythia. MC@NLO + Herwig shows good agreement with the measured bbbar-dijet
cross-section. However, it does not reproduce the measured inclusive
cross-section well, particularly for central b-jets with large transverse
momenta.Comment: 10 pages plus author list (21 pages total), 8 figures, 1 table, final
version published in European Physical Journal
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