122 research outputs found
Exploring small area demand for grocery retailers in tourist areas
No full textNewing, A., Clarke, G.P. and Clarke, M. 2014. Exploring small area demand for grocery retailers in tourist areas. Tourism Economics, 20(2), pp.407-427This paper uses data from a major loyalty card scheme to draw insights about the characteristics of grocery expenditure by tourists. The authors explore the volume, value and composition of store based visitor expenditure using consumer data from the loyalty card scheme. They focus on grocery spending at selected stores in Cornwall, a popular tourist destination in South West England. Theloyalty card data provide a valuable source rarely available for academic investigations. The authors are able to analyse visitor spend by socio-economic and geodemographic characteristics, drawing a range of comparisons with residential demand from within the store catchment areas. They demonstrate that visitor grocery expenditure is complex and varies by store, destination and type of customer. The paper presents evidence to suggest that the current approaches used to estimate sales uplift and local-level economic impact from visitor demand are unable to account for the complexities of this form of expenditure. Based on these insights, the authors recommend that sophisticated modelling is employed to estimate the impact of visitor expenditure
A multivariable Mendelian randomization analysis investigating smoking and alcohol consumption in oral and oropharyngeal cancer
No full textThe independent effects of smoking and alcohol in head and neck cancer are not clear, given the strong association between these risk factors. Their apparent synergistic effect reported in previous observational studies may also underestimate independent effects. Here we report multivariable Mendelian randomization performed in a two-sample approach using summary data on 6,034 oral/oropharyngeal cases and 6,585 controls from a recent genome-wide association study. Our results demonstrate strong evidence for an independent causal effect of smoking on oral/oropharyngeal cancer (IVW OR 2.6, 95% CI= 1.7, 3.9 per standard deviation increase in lifetime smoking behaviour) and an independent causal effect of alcohol consumption when controlling for smoking (IVW OR 2.1, 95% CI= 1.1, 3.8 per standard deviation increase in drinks consumed per week). This suggests the possibility that the causal effect of alcohol may have been underestimated. However, the extent to which alcohol is modified by smoking requires further investigation
Discovery and Mechanistic Study of a Totally Organic C<sub>(aryl)</sub>–C<sub>(alkyl)</sub>Oxygen Insertion Reaction
No full textWe
report an unprecedented photochemical oxygen insertion reaction
into an aromatic quinone methide. Insertion happens specifically within
a C(aryl)–C(alkyl) bond, whereas the
quinone methide moiety remains intact itself. Detailed mechanistic
studies, supported by DFT calculations, support a pathway in which
the p-QM plays a pivotal activating role
Discovery and Mechanistic Study of a Totally Organic C<sub>(aryl)</sub>–C<sub>(alkyl)</sub>Oxygen Insertion Reaction
No full textWe
report an unprecedented photochemical oxygen insertion reaction
into an aromatic quinone methide. Insertion happens specifically within
a C(aryl)–C(alkyl) bond, whereas the
quinone methide moiety remains intact itself. Detailed mechanistic
studies, supported by DFT calculations, support a pathway in which
the p-QM plays a pivotal activating role
Discovery and Mechanistic Study of a Totally Organic C<sub>(aryl)</sub>–C<sub>(alkyl)</sub>Oxygen Insertion Reaction
No full textWe
report an unprecedented photochemical oxygen insertion reaction
into an aromatic quinone methide. Insertion happens specifically within
a C(aryl)–C(alkyl) bond, whereas the
quinone methide moiety remains intact itself. Detailed mechanistic
studies, supported by DFT calculations, support a pathway in which
the p-QM plays a pivotal activating role
Sequential assessment of bowel function and anorectal physiology after anterior resection for cancer: a prospective cohort study
No full textAim: The aim of this study was to investigate changes in bowel function and anorectal physiology (ARP) after anterior resection for colorectal cancer. Method: Patients were recruited from November 2006 to September 2008. Cleveland Clinic Incontinence (CCI) scores and stool frequency were determined by patient questionnaires before surgery (t
0) and at three (t
3), six (t
6), nine (t
9) and 12 (t
12) months after restoration of intestinal continuity. ARP measurements were recorded at T
0, T
3 and T
12. Endoanal ultrasound was performed at T
0 and T
12. Results: Eighty-nine patients were included. CCI score increased postoperatively then normalized, whereas stool frequency did not change. Patients who had neoadjuvant radiotherapy or a lower anastomosis had increased incontinence and stool frequency in the postoperative period, whereas those with defunctioning stomas or open surgery had increased stool frequency alone. Maximum resting pressure, volume at first urge and maximum rectal tolerance were reduced throughout the postoperative period. Radiotherapy, lower anastomosis and defunctioning stoma (but not operative approach) altered manometric parameters postoperatively. Maximum rectal tolerance correlated with incontinence and first urge with stool frequency. The length of the anterior internal anal sphincter decreased postoperatively. Conclusions: Incontinence recovers in the first year after anterior resection. Radiotherapy, lower anastomosis, defunctioning stoma and open surgery have a negative influence on bowel function. ARP may be useful if bowel dysfunction persists beyond 12 months.
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"PROTON SPONGES": A RIGID ORGANIC SCAFFOLD TO REVEAL THE QUANTUM STRUCTURE OF THE INTRAMOLECULAR PROTON BOND
No full textAuthor Institution: Yale University, P. O. Box 208107, New Haven, CT, 06520; Johns Hopkins University, 3400 North Charles Street, Baltimore, MD, 21218; Brock University, St. Catherines, ON, Canada L2S 3A1Spectroscopic analysis of systems containing charged hydrogen bonds (e.g. the Zundel ion, ) in a vibrationally cold regime is useful in decongesting numerous anharmonic features common to room temperature measurements.[Roscioli, J. R.; et. al. Science 2007] This approach has been extended to conjugate acids of the "Proton Sponge" family of organic compounds, which contain strong intramolecular hydrogen bonds between proton donor (D) and acceptor (A) groups at the 1- and 8-positions. By performing vibrational predissociation spectroscopy on cryogenically cooled ions, we explore how the proximity and spatial orientation of D and A moieties relates to the spectroscopic signature of the shared proton. In the cases studied (), we observe strong anharmonic couplings between the shared proton and dark states that persist at these cryogenic temperatures. This leads to intense NH stretching features throughout the nominal CH stretching region (). Isotopic substitution has verified that the oscillator strength of these broad features is driven by NH stretching. Furthermore, the study of A = O(C=O)Ph has provided a spectroscopic snapshot of the shared proton at work as an active catalytic moiety fostering ester hydrolysis by first order acylium fission (). This is apparent by the high frequency carbonyl stretch at , which is a consequence of the strong hydrogen bond to the ether-ester oxygen atom. Thus, these "Proton Sponges" are useful model systems that unearth the quantum structure and reactivity of shared proton interactions in organic compounds
C–C Bond Activation and Demethylenation of Epoxides by Amine Radical Dications
No full textIn this note, we explore a unique reactivity pattern
that involves
a rare radical-based C–C bond scission of epoxides followed
by demethylenation. The reaction is accomplished by Selecfluor and
its radical dication working in tandem; a mechanism supported by experiment
and DFT calculations is proposed that involves the generation and
identification of a key reactive intermediate. The reaction seems
to be fairly general for 1,1-disubstituted epoxides
Poor oral health influences head and neck cancer patient survival: An International Head and Neck Cancer Epidemiology Consortium pooled analysis
No full textBackground: Poor oral health has been identified as a prognostic factor potentially affecting the survival of patients with head and neck squamous cell carcinoma. However, evidence to date supporting this association has emanated from studies based on single cohorts with small-To-modest sample sizes. Methods: Pooled analysis of 2449 head and neck squamous cell carcinoma participants from 4 studies of the International Head and Neck Cancer Epidemiology Consortium included data on periodontal disease, tooth brushing frequency, mouthwash use, numbers of natural teeth, and dental visits over the 10 years prior to diagnosis. Multivariable generalized linear regression models were used and adjusted for age, sex, race, geographic region, tumor site, tumor-node-metastasis stage, treatment modality, education, and smoking to estimate risk ratios (RR) of associations between measures of oral health and overall survival. Results: Remaining natural teeth (10-19 teeth: RR = 0.81, 95% confidence interval [CI] = 0.69 to 0.95; ≥20 teeth: RR = 0.88, 95% CI = 0.78 to 0.99) and frequent dental visits (>5 visits: RR = 0.77, 95% CI = 0.66 to 0.91) were associated with better overall survival. The inverse association with natural teeth was most pronounced among patients with hypopharyngeal and/or laryngeal, and not otherwise specified head and neck squamous cell carcinoma. The association with dental visits was most pronounced among patients with oropharyngeal head and neck squamous cell carcinoma. Patient-reported gingival bleeding, tooth brushing, and report of ever use of mouthwash were not associated with overall survival. Conclusions: Good oral health as defined by maintenance of the natural dentition and frequent dental visits appears to be associated with improved overall survival among head and neck squamous cell carcinoma patients
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