Search

Objective The aim of this study was to establish a triaging system for assessment of breast referrals from primary care to ensure safe and effective breast services without compromising breast cancer management. Background COVID-19 was officially declared a global pandemic on 11 March 2020, and with no effective treatment available, preventing spread has been paramount. Previously, all referrals from primary care were seen in the rapid-access breast clinic (RABC). Clinic appointments exposed patients and healthcare professionals to risk. Method Initial triage during the lockdown was in line with national governing body guidance, rejected low risk referrals and streamed remaining patients through a telephone consultation to RABC or discharge. A modified triage pathway streamed all patients through virtual triage to RABC, telephone clinic or discharge with advice and guidance categories. Demographics, reasons for referral and outcomes data were collected and presented as median with range and frequency with percentages. Results Initial triage (23 March–23 April 2020) found fewer referrals with a higher percentage of breast cancer diagnoses. Modified triage (22 June–17 July 2020) resulted in a 35.1% (99/282) reduction in RABC attendance. Overall cancer detection rate remained similar at 4.2% of all referrals pre-COVID (18/429) and 4.3% (12/282) during modified triage. After six months follow-up of patients not seen in RABC during the modified triage pathway, 18 patients were re-referred to RABC and none were diagnosed with cancer. Conclusion A modified triage pathway has the potential to improve triage efficiency and prevent unnecessary visits during the COVID-19 pandemic. Further refinement of pathway is feasible in collaboration with primary care.

The aim of this study was to investigate the role of the passive layers in galvanic corrosion of Ti–Nb alloys and commercially pure titanium (cp-Ti). Ti–Nb alloys with 5, 10, 15, and 20 wt% niobium (Nb) content were prepared using an arc-melting technique under high purity Ar gas. The cp-Ti was used as a control. The electrochemical corrosion behaviors were investigated by A.C. impedance, potentiodynamic polarization, and galvanic corrosion tests. According to the results of impedance analysis, the passivation layer on Ti–Nb alloys consisted of outer, intermediate, inner, and metal defect layers, while the passivation layer on cp-Ti consisted of outer, intermediate, and inner layers. According to the results of anodic polarization tests, Ti–Nb alloys exhibited better zero potentials and reduced zero current densities. The outer layer and the inner layer of Ti–Nb alloys and cp-Ti had an effect mainly on the values of the initial galvanic current density and the sign of galvanic current density, respectively. Ti–10Nb alloy exhibited a relatively high initial galvanic current density compared to the other Ti–Nb alloys. Unlike Ti–5Nb, Ti–10Nb, and Ti–15Nb, which exhibited galvanic current densities with a minus sign, Ti–20Nb exhibited a galvanic current density with a plus sign due to its weaker inner layer than that of Ti.

AIM The National Bowel Cancer Screening Programme (NBCSP) was introduced in the West Midlands in 2006. Studies, including the UK Bowel Cancer Screening Pilot, have reported an 18% reduction in mortality. This regional study assesses the impact of screening on elective and emergency colorectal cancer (CRC) surgery. METHOD Data were extracted from the West Midlands cancer registration database for CRC diagnosed in residents of the West Midlands between 1998 and 2010. Screen-detected cancers were identified by matching to the NBCSP database. Mode of admission and intervention was obtained by matching to Hospital Episode Statistics and the classification of Interventions and Procedures code. RESULTS Of 42,082 patients diagnosed with CRC, 30,309 received surgical treatment. From 1998 to 2005, the number of patients who underwent emergency surgery increased from 4362 to 18,357, with the proportion each year remaining constant (23.85 ± 0.95% each year). In the screening age group (60-69 years) over the same period, emergency surgery was performed in 918 of 4831 patients (19.15 ± 1.65% each year). Following the introduction of screening, the emergency surgery rate decreased each year, reaching 16% (406/2520) in all patients and 12% (101/829) in the screening age group in 2010 (P < 0.001). These changes in emergency surgery were mirrored by increases in elective surgery. CONCLUSION The NBCSP has had a positive impact on elective and emergency surgery for CRC in the West Midlands.

In this paper, we expand the double price elasticity theory developed by Greenhut, Hwang, and Ohta (1974) by including a general cost condition for a profit-maximizing monopolist, cartel, or price leader. Our model generalizes the conventional second-order condition as it incorporates the non-converging price elasticity. Contrary to the textbook prediction, a structural changes or an income effect in tobacco, crude oil and other demand inelastic markets can render the price elasticity of demand to oscillate for a long time but never reach its theoretical limit even in a very long time.

Recently, a quantum mechanical Class II force field (QMFF) was derived from a fit of HF/6–31G* ab initio energy and energy derivative data for alkanes, and a comparison of this quantum force field and the ab initio energy and energy derivatives was presented. In this work, the quantum force field is further evaluated with regard to its accuracy, and, more importantly, transferability. A detailed comparison between structures, frequencies, and energies calculated from quantum mechanics and from the classical analytical form is given for a set of molecules selected from both those used in the original training set and molecules selected from outside the training set. None of these properties were used directly in the original derivation of the force field. In order to assess the importance of anharmonic and coupling interactions that occur in and contribute to molecular energy surfaces, the results are compared to a diagonal quadratic force field. It is demonstrated that the QMFF functional form is capable of calculating the ab initio bond lengths, bond angles, torsion angles, and conformational energy differences to an rms accuracy of 0.003 A, 0.4°, 1.2°, and 1.0 kcal/mol, respectively. This compares quite well to corresponding deviations of 0.006 A, 0.8 A, 2.3°, and 3.3 kcal/mol for a harmonic diagonal force field. Excluding three- or four-membered rings, the QMFF rms frequency deviations were 24 cm−1, which again is much better than the ˜100 cm−1 deviations for the harmonic diagonal force field. Larger average rms frequency deviations of 36 and 71 cm−1 were found with QMFF for molecules with three- and four-membered rings. An in-depth analysis of C-H and C-C bond length, H-C-H, H-C-C, and C-C-C bond angle, and C-C-C-C torsion angle deviations is also presented, along with a similar characterization of frequency deviations in C-H stretching, C-C stretching, C-C-C bending, and torsion modes. It is concluded from these results that the use of quantum energy surfaces allows us to derive a (Class II) functional form which is not only more accurate, but also more transferable than previous generation force fields.

New limits are presented on the cross section for Weakly Interacting Massive Particle (WIMP) nucleon scattering in the KIMS CsI(T) detector array at the Yangyang Underground Laboratory. The exposure used for these results is 24524.3 kg\cdotdays. Nuclei recoiling from WIMP interactions are identified by a pulse shape discrimination method. A low energy background due to alpha emitters on the crystal surfaces is identified and taken into account in the analysis. The detected numbers of nuclear recoils are consistent with zero and 90% confidence level upper limits on the WIMP interaction rates are set for electron equivalent energies from 3 keV to 11 keV. The 90% upper limit of NR event rate for 3.6-5.8 keV corresponding to 2-4 keV in NaI(T) is 0.0098 counts/kg/keV/day which is below the annual modulation amplitude reported by DAMA. This is incompatible with interpretations that enhance the modulation amplitude such as inelastic dark matter models. We establish the most stringent cross section limits on spin-dependent WIMP-proton elastic scattering for the WIMP masses greater than 20 GeV/c2., 5 pages, 6 figures

KIMS is a dark matter search experiment using low background CsI(TB) crystals at Yangyang Underground Laboratory in Korea. With a total exposure of 3409 kg⋅d data, we set a new limit on WIMP‐nucleon cross section. We achieved the most stringent limit on the spin‐dependent interaction for a pure proton case. We were able to exclude the DAMA signal region for both spin‐dependent and spin‐independent interaction for the WIMP mass greater than 20 GeV/c2. KIMS experiment is upgraded with 12 CsI(TB) crystals corresponding to a total mass of 104 kg and accumulating data since Jan. 2008.

Abrus agglutinin (AAG), a low-toxicity protein from the plant Abrus precatorius, is less lethal than abrina (ABRa) in mice (LD(50) = 5 mg/kg versus 20 microg/kg of body weight). Nucleotide sequence analysis of a cDNA clone encoding full-length AAG showed an open reading frame with 1641 base pairs, corresponding to a 547-amino acid residue preproprotein containing a signal peptide and a linker region (two amino acid residues) between the AAG-A and AAG-B subunits. AAG had high homology to ABRa (77.8%). The 13 amino acid residues involved in catalytic function, which are highly conserved among abrins and ricins, were also conserved within AAG-A. The protein synthesis inhibitory activity of AAG-A (IC(50) = 3.5 nM) was weaker than that of ABRa-A (0.05 nM). Molecular modeling followed by site-directed mutagenesis showed that Pro(199) of AAG-A, located in amphiphilic helix H and corresponding to Asn(200) of ABRa-A, can induce bending of helix H. This bending would presumably affect the binding of AAG-A to its target sequence, GpApGpAp, in the tetraloop structure of the 28 S rRNA subunit and could be one of the major factors contributing to the relatively weak protein synthesis inhibitory activity and toxicity of AAG.

The alpha-helical coiled coil motif is among the first characterized and widely found architecture of protein structures. We report here a fast and reliable approach of simulated annealing molecular dynamics (SA/MD) for predicting the three-dimensional structures of various alpha-helical coiled coils of heptad repeat. One key element of our simulation involves a geometric restraint requiring residues occupying the first and fourth positions of the heptad to orient to the angle of their respective statistical average derived from a survey of coiled-coil structures deposited in the Protein Data Bank. Another is the incorporation of subunit rotation and inversion operations for generating symmetrized protein assemblies during the dynamics simulations. The procedure is fully automated and can be applied to different oligomerization states of identical subunits, as well as both parallel and antiparallel arrangements. Despite simplicity, the formation of five coiled-coil prototype systems driven by the restraint-based SA/MD approach shows that the level of prediction accuracy achieved previously by more elaborate procedures can be retained. The present work thus provides validation of a simulation approach that can be employed to utilize a wide variety of knowledge-based geometric restraints for structural prediction of symmetrical or pseudo-symmetrical protein systems.

The methodology for deriving class II force fields has been applied to acetal, hemiacetal, and carbohydrate compounds. A set of eighteen model compounds containing one or more anomeric centers was selected for generating the quantum mechanical energy surface, from which the force field was derived and the functional form assessed. The quality of the fit was tested by comparing the energy surface predicted by the force field with ab initio results. Structural, energetic, and dynamic properties (vibrational frequencies) were analyzed. In addition, alpha and beta anomeric equilibrium structures and energies of 2-methoxytetrahydropyran, 2-deoxyribose, and glucose were computed at the HF/6-31G* and higher ab initio levels. These calculations provide test data from molecules outside the training set used to derive the force field. The quantum calculations were used to assess the ability of the class II force field and two quadratic diagonal (class I) force fields, CVFF, and Homans' extension of the AMBER force field, to account for the anomeric effects on the structural and energetic properties of carbohydrate systems. These class I force fields are unable to account for observed structural and energetic trends, exhibiting deviations as large as 5 kcal/mol in relative energies. The class II force field, on the other hand, is shown to reproduce anomeric structural as well as energetic differences. An energy component analysis of this force field shows that the anomeric differences are dominated by torsional energies, although coupling terms, especially angle/torsion, also make significant contributions (roughly 1 kcal/mol in glucose). In addition, the force field accurately accounts for both anomeric and exo-anomeric energy differences in 2-methoxytetrahydropyran, and anomeric energy differences in 2-deoxyribose and glucose.

A 61-year-old woman attended the breast clinic with unresolving mastitis and an associated mass, following failed treatment with antibiotics. Triple assessment confirmed idiopathic granulomatous mastitis. Unresponsive to further conservative management and steroid therapy, she underwent surgical excision and made uneventful recovery. No evidence of recurrence was detected at 18 months follow-up.

This paper extends Löschian theory towards the end of claiming itsapplicability to heterogeneous space economies as well as to the homogeneous space economy. It then tests the theory by examining the relationships between fixed costs and market-area sizes. The result is an empirical demonstration that the level of fixed costs in the United States is so low that market areas too large to be approximated by the optimal hexagonal market-area shape are not likely to be associated with competition in free-enterprise countries. It is in fact indicated that competitive firms sell over comparatively small market areas. The related conclusion follows that there is nothing in market-area studies (empirical or theoretical) that would imply inefficiency or failure to maximize consumer wants.

This paper derives and compares aggregate demand functions for a given product in a spaceles and spatial economy in which buyers are identical in number, income, and tastes. The profit maximizing prices in each system are then derived, following which an analysis is provided of the impact on spatial prices of changing distributions of buyers over the space. The price trends in a population expanding economy are determined, before and after the nation's frontiers have been reached. The paper thus presents a view of how the concept of economic space and, in effect, its related analysis of the prices of spatial sellers yields a theory of the firm which intrinsically contains perspectives vital to research in the fields of economic theory.