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The aim of this study is to evaluate the perceptions of prospective tourists through parameters by which the tourism and hospitality service sector can withstand the widespread implications to the sector as a result of the current pandemic. In turn this will lead to weighing up the means for recovery. The identified parameters are then classified, categorized and linked up with supply chain drivers to obtain a holistic picture that can feed into strategic planning from which the tourism and hospitality service sector could utilize to establish a resilient supply chain. This data can provide deep insight for both theorists and practitioners to utilize. It was found that reforming six supply chain drivers, whilst at the same time developing core competencies, is the central essence of a resilient supply chain within the tourism and hospitality business sector (who are at present working hard to counterbalance the many threats and consequent risks posed due to the pandemic). [ABSTRACT FROM AUTHOR]

The protective carapace of Skogsbergia lerneri, a marine ostracod, is scratch-resistant and transparent. The compositional and structural organisation of the carapace that underlies these properties is unknown. In this study, we aimed to quantify and determine the distribution of chemical elements and chitin within the carapace of adult ostracods, as well as at different stages of ostracod development, to gain insight into its composition. Elemental analyses included X-ray absorption near-edge structure, X-ray fluorescence and X-ray diffraction. Nonlinear microscopy and spectral imaging were performed to determine chitin distribution within the carapace. High levels of calcium (20.3%) and substantial levels of magnesium (1.89%) were identified throughout development. Amorphous calcium carbonate (ACC) was detected in carapaces of all developmental stages, with the polymorph, aragonite, identified in A-1 and adult carapaces. Novel chitin-derived second harmonic generation signals (430/5 nm) were detected. Quantification of relative chitin content within the developing and adult carapaces identified negligible differences in chitin content between developmental stages and adult carapaces, except for the lower chitin contribution in A-2 (66.8 ± 7.6%) compared to A-5 (85.5 ± 10%) (p = 0.03). Skogsbergia lerneri carapace calcium carbonate composition was distinct to other myodocopid ostracods. These calcium polymorphs and ACC are described in other biological transparent materials, and with the consistent chitin distribution throughout S. lerneri development, may imply a biological adaptation to preserve carapace physical properties. Realisation of S. lerneri carapace synthesis and structural organisation will enable exploitation to manufacture biomaterials and biomimetics with huge potential in industrial and military applications. [ABSTRACT FROM AUTHOR]

Heat exchange devices involving confined heated cylinders in crossflow require wake stability to minimize hydraulic losses, which are typically accompanied by a considerable loss in heat transfer. To address this problem, passive wake control for laminar flow past a cylinder is introduced in the form of wavy channel walls around the cylinder. The resultant effects on heat transfer and drag are investigated in detail for a range of Reynolds numbers (Re = = 20–200), blockage ratios (β = 0.5–0.9) and Prandtl numbers (Pr = 0.25–100). For the given range of parameters, it is shown that the wavy channel reduces cylinder drag by a minimum of ∼ 36 % and a maximum of ∼ 95 %, at the expense of ∼ 8 % and ∼ 40 % loss in heat transfer, respectively, compared to the plane channel. Thermal-hydraulic performance of the wavy channel compared to the plane channel for Pr = 0.744, is improved by ∼ 14 % for β = 0.5 and ∼ 160 % for β = 0.9. Therefore, the performance enhancement brought about by the wavy channel provides an appropriate trade-off between drag reduction and heat transfer loss. [ABSTRACT FROM AUTHOR]

The Skogsbergia lerneri is a marine ostracod which possesses a carapace that is both protective and transparent. Since development of this carapace and how it is maintained in the adult is not known, the aim of this investigation was to carry out an in-depth ultrastructural study of the ostracod carapace at different developmental stages. Standard transmission electron microscopy and novel serial block face scanning electron microscopy (SBF-SEM) were undertaken to discern carapace ultrastructure in both two and three dimensions. Analysis revealed a carapace consisting of the same basic layer structure as other myodocopid ostracods, namely an epicuticle, exocuticle, endocuticle and membranous layer, but with a thinner adult carapace of mean thickness of 19.2 ± 1.78 µm, n = 5. The carapace layers, except for instar 1 ostracods, had similar relative proportions throughout development. The endocuticle and membranous layer thickened through advancing developmental stages due to an increase in calcified crystalline polyhedrons and a greater number of chitinous lamellae in the membranous layer. Crystalline polyhedron dimensions were significantly smaller near the boundary with the membranous layer. The borders between the carapace layers were indistinct; SBF-SEM revealed an abundance of epicuticle projections into the exocuticle and apparent gradual merging at the boundary of the exocuticle and the endocuticle. Here, we discuss how the S. lerneri carapace layer structure has evolved to serve a specific mechanical function, allowing surface protection and rigidity. In addition, we suggest that the lack of pigment and graduated layer boundaries contribute to the transparency of the carapace. [ABSTRACT FROM AUTHOR]

Bone marrow (BM) genetic abnormalities in myelodysplastic syndrome (MDS) have provided important biological and prognostic information; however, frequent BM sampling in older patients has been associated with significant morbidity. Utilizing single-nucleotide polymorphism array (SNP-A) and targeted gene sequencing (TGS) of 24 frequently mutated genes in MDS, we assessed the concordance of genetic abnormalities in BM and peripheral blood (PB) samples concurrently from 201 MDS patients. SNP-A karyotype in BM was abnormal in 108 (54%) and normal in 93 (46%) patients, with 95% (190/201) having an identical PB karyotype. The median copy number (CN) for deletions was significantly lower in BM (CN:1.4 (1-1.9)) than in PB (CN:1.5 (1-1.95), P<0.001). Using TGS, 71% (130/183) patients had BM somatic mutations with 95% (124/130) having identical mutations in PB. The mutant allele burden was lower in PB (median 27% (1-96%)) compared with BM (median 29% (1-100%); P=0.14) with no significant difference in the number, types of mutations or World Health Organization subtype. In all patients with discordant SNP (n=11) and mutation (n=6) profiles between BM and PB, shared abnormalities were always present irrespective of treatment status. Overall, 86% of patients had a clonal aberration with 95% having identical SNP-A karyotype and mutations in PB, thus enabling frequent assessment of response to treatment and disease evolution especially in patients with fibrotic or hypocellular marrows. [ABSTRACT FROM AUTHOR]

Somatic mutations or deletions of TP53 and PTEN in ductal carcinoma in situ lesions have been implicated in progression to invasive ductal carcinomas. A recent molecular and mutational analysis of breast cancers revealed that inactivation of tumor suppressors, p53 and PTEN, are strongly associated with triple negative breast cancer. In addition, these tumor suppressors have important roles in regulating self-renewal in normal and malignant stem cells. To investigate their role in breast carcinogenesis, we knocked down these genes in human mammary cells and in non-transformed MCF10A cells. p53 and PTEN knockdown synergized to activate pro-inflammatory interleukin-6 (IL6)/Stat3/nuclear factor κB signaling. This resulted in generation of highly metastatic epithelial-to-mesenchymal transition-like cancer stem cells resulting in tumors whose gene expression profile mimicked that found in basal/claudin-low molecular subtype within the triple negative breast tumors. Constitutive activation of this loop in transformed cells was dependent on proteolytic degradation of suppressor of cytokine signaling 3 (SOCS3) resulting in low levels of this protein in basal/claudin-low cell lines and primary tumors. In non-transformed cells, transient activation of the IL6 inflammatory loop induced SOCS3 expression leading to pathway inactivation. In transformed cells, enforced expression of SOCS3 or interfering with IL6 pathway via IL6R blockade inhibited tumor growth and metastasis in mouse xenograft models. Furthermore, circulating tumor cells were significantly reduced in tumor-bearing animals when treated with anti-IL6R antibodies. These studies uncover important connections between inflammation and carcinogenesis and suggest that blocking pro-inflammatory cytokines may be utilized as an attractive strategy to target triple negative breast tumors, which currently lacks molecularly targeted therapies. [ABSTRACT FROM AUTHOR]

Sand is extensively used in construction of buildings. The presence of natural radioactivity in it results in internal and external exposure to the general public. Therefore, it is desirable to determine the concentration of naturally occurring radio-nuclides, namely Th, Ra and K in sand. In this regard, in continuation of our earlier studies, 42 sand samples were collected from fourteen different locations along the banks of river Indus from Gilgit to Lowarian in the northern part of Pakistan covering an area of ~500 km. In order to measure the specific activities in these samples, a P-type coaxial high purity germanium based gamma-ray spectrometer was used. Average values of the measured activities of Ra, Th and K were found to be 45.6 ± 3, 74.73 ± 3 and 339.8 ± 3.6 Bq kg, respectively which results in an average absorbed dose rate 83.54 nGy h. From the measured activities, average radium equivalent activity was found to be 178.59 Bq kg. External and internal hazard indices were also calculated and found to be 0.48 and 0.61, respectively. Average effective dose expected to be received due to the gamma rays was 0.26 mSv y. Measured natural radioactivity, hazard indices and effective doses received by the population were found to be within the recommended limits. [ABSTRACT FROM AUTHOR]

The history of groundwater aggressiveness evaluation procedures applied in the Slovak Republic is summarized and compared with the newly adopted European technical standard STN EN 206-1. The methodology of data acquiring and processing for groundwater aggressiveness evaluation was proposed. The procedure included basic principles of data mining, requested number of chemical analyses and ways of groundwater aggressiveness assessment. Ways of results interpretation and graphical visualization were proposed, too. The procedure was applied in the area of the Horna Nitra in Slovakia. A total number of 953 groundwater analyses were used to assess the groundwater aggressiveness. The resulting map of zoning comprised eight groundwater aggressiveness zones. Zones with the non-aggressive degree (X0) groundwater to moderately aggressive degree (XA2) were delineated. The aggressiveness was caused mainly by presence of aggressive carbon dioxide (depending on the rock type in the area) and by lowered pH values in association with increased sulfate contents in areas of brown coal mining activities and in heavy industrialized areas. The compilation of a locality map was proposed, where for each municipality type and degree of aggressiveness is assessed. It should serve to local authorities as background information within the decision-making process connected to the permission of construction work. [ABSTRACT FROM AUTHOR]

Soil samples were collected from different localities of districts Jhelum, Chakwal, Rawalpindi and Attock, Punjab Province, Pakistan with an aim to measure naturally occurring radionuclides, namely Ra, Th, K and fallout Cs radionuclide using a P-type coaxial high purity germanium (HPGe) γ-ray spectrometer. Measured specific activities of Ra, Th and K in these soil samples ranged from 26.02 ± 7.11 to 93.54 ± 8.13 Bq kg, 29.34 ± 2.58 to 114.41 ± 2.80 Bq kg and 348.15 ± 3.20 to 752.98 ± 4.20 Bq kg, respectively. Activity due to Cs was observed in some locations which ranged from 0.4 ± 0.2 to 7.8 ± 0.3 Bq kg. From the measured activity concentrations, radium equivalent activity concentrations were determined followed by calculations of mean absorbed dose rate and mean annual effective dose for the inhabitants of the studied area. The mean radium equivalent activity, internal and external hazard indices values came out to be 179.26 ± 11.93 Bq kg, 0.64 ± 0.05 and 0.48 ± 0.03, respectively. Indoors and outdoor average annual effective dose values were found to be 0.42 ± 0.03 and 0.10 ± 0.01 mSv, respectively. Present data have been compared with the published data for other parts of the world and found to be safe for public and environment. [ABSTRACT FROM AUTHOR]

Background: No data exist on the population prevalence of, or risk factors for, human papillomavirus (HPV) infection in predominantly Muslim countries in Asia.Methods: Cervical specimens were obtained from 899 married women aged 15-59 years from the general population of Karachi, Pakistan and from 91 locally diagnosed invasive cervical cancers (ICCs). HPV was detected using a GP5+/6+ PCR-based assay.Results: The prevalence of HPV in the general population was 2.8%, with no evidence of higher HPV prevalence in young women. The positivity of HPV was associated with women's lifetime number of sexual partners, but particularly with the age difference between spouses and other husbands' characteristics, such as extramarital sexual relationships and regular absence from home. The HPV16/18 accounted for 24 and 88% of HPV-positive women in the general population and ICC, respectively.Conclusion: Cervical cancer prevention policies should take into account the low HPV prevalence and low acceptability of gynaecological examination in this population. [ABSTRACT FROM AUTHOR]

This work compares the performance of traditional phenomelogical Woods-Saxon (WS) and squared WS (SWS) potentials with that of a non-monotonic (NM) potential, microscopically derived using the energy-density functional (EDF) formalism from a realistic two-nucleon potential that includes the Pauli priciple. The experimental differential cross-sections (DCS) for the 6Li elastic scattering by 28Si over the incident energies E$Li$ = 7.5-99.0 MeV are well accounted for using the NM potential without the need of renormalization. At higher energies, in the range of 135.0-318.0MeV, the EDF-generated NM potential parameters need a revision for the satisfactory description of the DCS data. The DCS data in the entire energy range of 7.5-318.0 are also well described by the WS and SWS potentials. The inclusion of a static spin-orbit potential to the NM, WS and SWS central potentials is found to reproduce the features of the vector analyzing power iT11 data at 22.8MeV reasonably well in each of the cases. However, the WS and SWS potential parameters needed to describe the DCS and iT11 data are found inconsistent in terms of the variations of the real volume integrals per nucleon pair (VJR) with the incident energy. On the other hand, the EDF-generated NM potential is found to be consistent in terms of VJR and satisfactorily accounts for the DCS data in the entire range of energies considered herein and the features of the iT11 data at 22.8MeV. [ABSTRACT FROM AUTHOR]

The recently modified Kolbenstvedt (MKLV) model [Eur. Phys. J. D 37, 361 (2006)], developed for electron impact ionization (EII) of the K-shell atomic targets, has been extended to generalize its two parameters in terms of the electronic orbitals nl. The generalized MKLV (GKLV) with two sets of the species independent parameters for the same nl, one set for the ionization of inner orbits and another for the outermost orbit, is found profoundly successful in accounting for the EII cross section data of the K, L and M-shell neutral atoms with atomic numbers Z = 1-92 for the incident energies up to 1000 MeV in a consistent manner. [ABSTRACT FROM AUTHOR]

A modification of the Kolbensvedt model, MKLV, in terms of ionic, correlation (between the incident and target electrons) and relativistic corrections, is proposed to calculate the K-shell electron impact ionization cross-sections of neutral and ionic targets. The modified model, with a single set of parameters, is found to reproduce satisfactorily the experimental data for the neutral H, Al, Ar, Mn, Ge, Mo, Ag, Sn, Au, Bi and U and ionic Li+, B4+ and O7+ targets better than the existing empirical models from threshold energies to as high as 104 MeV. For the Ag target, the calculations from MKLV follow closely the results of Scofield, and for Au, those of Scofield, and Ndefru and Malik, both done in the relativistic Born approximation with the Møller interaction, at energies higher than the peak region. [ABSTRACT FROM AUTHOR]

Within the context of a statistical model, that incorporates final-state interaction between a pair of fragments, we have calculated the energy spectra associated with the production of different isobaric pairs as a function of their lab kinetic energy and isobaric and elemental distributions of nuclei produced in the 4He$ + $28Si reaction at cm incident energies of 102.7, 173.7, 300, 500, and 1000MeV. Double differential cross-section of isobars 16, 20, and 24 as a function of their lab kinetic energies at 30° and the same for isobar 24 at 10°, 30°, 60°, and 90° have been calculated at cm incident energies of 102.7 and 173.7MeV and compared with the data of Woo et al. Calculated yields follow the trend of the data at each angle, and calculated angular distributions also reproduce the general trend of the observed ones. A key feature of the model is that it allows for fragments to be emitted in ground states as well as in excited states that are allowed by the conservation of energy. The analysis establishes that the fragments are emitted in excited state. The excitation energies for A = 24 and 16 are deduced from the data. The observed angular distributions for A = 7, 12, 16, 20, 24, and 28 are well accounted for assuming them to be emitted in excited states. The relative production probabilities for different elements and isobars are energy dependent. The yields for unstable elements, 5Li, 8Be, and 26Al, are found to be significant. The relative fragmentation probabilities of all allowed isotopic pairs have been presented. [ABSTRACT FROM AUTHOR]

This study examined the clinical workload, outcome and direct costs of managing women with sexual dysfunction in an NHS clinic in the UK. A retrospective analysis of a 3-month period showed that of 47 referrals to the clinic, 38 undertook treatment. The therapists' assessments suggested that over 80% of patients improved on treatment. The average cost per patient was £472 (compared to £335 per annum for erectile dysfunction, which included physician's and drug costs). The average cost by type of practitioner was £278 (psychologist), £322 (physician), £532 (physician and psychologist) and £597 (sex therapist). Patients required between 1 and 51 treatment sessions, which were mainly restricted to psychological therapy. Female sexual dysfunction (FSD) represents a significant economic burden to the NHS. Further research on the potential role and cost effectiveness of pharmacological agents for FSD is warranted.International Journal of Impotence Research (2004) 16, 130-134. doi:10.1038/sj.ijir.3901179 Published online 12 February 2004 [ABSTRACT FROM AUTHOR]

A folding potential describing the a-scattering on 16O over a broad energy range 2 5.8-146.0 MeV is constructed on the basis of a-like cluster and unclustered-nucleon configurations of 16O The resulting potential does not need any renormalization to fit the angular distribution of elastic cross-sections. The effects of the repulsive part of a-a and a-nucleon interactions are investigated. The analysis suggests that both the a-a repulsive potential and the unclustered nucleonic configuration in the target are important to describe the scattering data over a broad range of incident energies. The root-mean-square radius for the 16O nucleus is deduced. [ABSTRACT FROM AUTHOR]

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