Cleaner Technologies as an Aspect of Sustainable Tourism: Carribbean Case Studies

Tourists are becoming increasingly sophisticated in their selection of tourism destination. A major factor that has been gaining importance in their choice set is the environmental quality of their preferred destination. Tourism planners need to recognize that the sustainability of their destination and its various offerings necessitates the consideration of environmental protection and conservation-related issues. This dissertation undertakes the case study methodology to explore the link between implementing cleaner technologies, a major environmental issue, and sustainable tourism. The Caribbean is a region in the world that is strongly dependent on tourism for its economic development. Thus the analysis of how cleaner technology is being used to enhance and sustain the tourism industry should be of interest to policymakers and managers in the tourism industry, not only in the Caribbean, but also in other tourism destinations worldwide, including those in the United States. As part of this project, case studies were conducted in five Caribbean islands. Case studies analysis indicates that cleaner technologies are playing a role in enhancing the sustainability of the Caribbean tourism industry by generating positive environmental/physical as well as economic impacts on the destination. It was also found that there is a Caribbean tourism cluster focused on developing an environmentally sound tourism product. The study revealed that Caribbean governments are to some extent aware of the need to facilitate the widest use of cleaner technology in the hotel sector. It was found that pressure from civil society on the islands studied was not a factor in the use of cleaner technologies in the tourism sector. Rather hotel operators recognized the cost saving from using cleaner technologies, as well as the marketing benefits. The evidence thus suggests that over time more hotels in the tourism sector will invest in cleaner technology

Ligand exchange reactions of [Re₂(μ-OR)₃(CO)₆]⁻(R = H, Me) with sulfur, selenium, phosphorus and nitrogen donor ligands, investigated by electrospray mass spectrometry

Negative-ion electrospray mass spectrometry has been used to investigate the reactions of the dinuclear rhenium aggregates [Re₂(μ-OH)₃(CO)₆]⁻ 1 and [Re₂(μ-OMe)₃(CO)₆]⁻ 2 with a range of thiols, benzeneselenol, and some other sulfur-, phosphorus- and nitrogen-based ligands. Typically up to three of the hydroxo ligands are replaced by simple thiolates, giving the series of species [Re₂(OH)₂(SR)(CO)₆]⁻, [Re₂(OH)(SR)₂(CO)₆]⁻, and [Re₂(SR)₃(CO)₆]⁻. Similarly, reaction of 1 with H₂S gives the species [Re₂(μ-SH)₃(CO)₆]⁻, which undergoes an analogous fragmentation process to [Re₂(μ-OH)₃(CO)₆]⁻, at high cone voltages, by loss of H₂S and formation of [Re₂(S)(SH)(CO)₆]⁻. With ligands which are good chelating agents (such as dithiocarbamates R₂NCS₂⁻, and thiosalicylic acid, HSC₆H₄CO₂H) initial substitution of one or two OH groups readily occurs, but on standing the dimer is cleaved giving [Re(S₂CNR₂)₂(CO)₃]⁻ and [Re(SC₆H₄CO₂)(CO)₃]⁻. The different reactivities of the dithiol reagents benzene-1,2- and benzene-1,4-dimethanethiol towards 1 are also described. Complex 1 also reacts with aniline, and with primary (but not secondary) amides RC(O)NH₂, giving monosubstituted species [Re₂(OH)₂(NHPh)(CO)₆]⁻ and [Re₂(OH)₂{NHC(O)R}(CO)₆]⁻ respectively. The reactions with adenine and thymine, and with the inorganic anions thiocyanate and thiosulfate, are also described

Synergistic effects of dual-electrocatalyst FeOOH/NiOOH thin films as effective surface photogenerated hole extractors on a novel hierarchical heterojunction photoanode structure for solar-driven photoelectrochemical water splitting

Herein, we report the rational design of a novel hierarchical V2O5/BiVO4 heterojunction photoanode structure with rGO interlayer that functionalises as photogenerated electron collector, and dual electrocatalyst thin films of FeOOH and NiOOH as photogenerated hole extractors for solar-driven PEC water splitting. Results showed that the novel hierarchical FTO/V2O5/rGO/BiVO4/FeOOH/NiOOH photoanode exhibited an unprecedented and stable photocurrent density of 3.06 mA/cm2 at 1.5 V vs Ag/AgCl, and an apparent cathodic onset potential shift down to 0.2 V under AM 1.5 G simulated solar light illumination. The significant enhancement in PEC performance is ascribed to band potentials matching between V2O5 and BiVO4 in forming a Type II staggered heterojunction alignment, and further coupling with rGO interlayer and dual-electrocatalyst thin films as photogenerated electron collector and photogenerated hole extractors, respectively. Three different configurations of the novel hierarchical FTO/V2O5/rGO/BiVO4 photoanodes without electrocatalyst, with mono- and dual-electrocatalyst thin films were systematically examined. It was proven though EIS and IMPS measurements that the dual-electrocatalyst configuration photoanode exhibited the shortest transit time (τ) of 31.8 ms for the diffusion of photogenerated electrons to the counter electrode, and the lowest charge transfer resistance across the interface of electrode/electrolyte as estimated using the Randles-Ershel model. We believe that the proof-of-principle work described here not only provides an in-depth understanding on the roles of electrocatalyst thin films but also provides a design guide over the incorporation of electrocatalyst materials for further improving the photogenerated charge carrier dynamics in photoanodes used in solar-driven PEC water splitting

End of life content in geriatric textbooks: what is the current situation?

BACKGROUND: Physicians caring for elderly people encounter death and dying more frequently than their colleagues in most other disciplines. Therefore we sought to examine the end-of-life content in popular geriatric textbooks and determine their usefulness in helping geriatricians manage patients at the end of their lives. METHODS: Five popular geriatric textbooks were chosen. Chapters on Alzheimer's disease, stroke, chronic heart failure, chronic obstructive pulmonary disease and lung cancer were examined because of their high mortality rates among the elderly patients. Text relevant to end-of-life care was highlighted. Two reviewers independently coded text into 10 pre specified domains and rated them for the presence of end-of-life information. Content was rated as absent, minimally helpful, or helpful. The proportion of helpful information was calculated. RESULTS: The textbook with the best end-of-life coverage contained 38% helpful information, the worst had only 15% helpful information. Minimally helpful information ranged from 24% to 50%. As much as 61% of the content in one textbook contained no helpful information at all. Of the ten domains, epidemiology, disease progression and prognostic factors were fairly well covered. Information on advance care planning, ethical issues, decision making and effects of death and dying on patient's family were generally lacking under the individual diseases though they were covered as general topics in other parts of the textbooks. All except one textbook dedicated a chapter to the care of the dying. CONCLUSION: This study showed that end-of-life content in geriatric textbooks differed significantly. Most of the textbooks lack good coverage on end-of-life care and more can be done to improve on this

A Type II n-n staggered orthorhombic V2O5/monoclinic clinobisvanite BiVO4 heterojunction photoanode for photoelectrochemical water oxidation: Fabrication, characterisation and experimental validation

Conventional photoanode using a singular semiconductor material is not technically viable for photoelectrochemical (PEC) water oxidation owing to the properties relating to its wide band gap, sluggish charge mobility, as well as poor separation and rapid recombination of photogenerated charge carriers. The main aim of this study was to fabricate an n-n heterojunction photoanode of V2O5/BiVO4 via a facile electrodeposition synthesis method in order to overcome the technical bottlenecks encountered in conventional singular photoanode structures. Additionally, the synergistic effect of band potentials matching and conductivity difference between BiVO4 and V2O5 were studied using LSV, IMPS, EIS, HR-TEM, XRD, XPS, Raman and ultraviolet-visible spectroscopies. This was followed by the performance evaluation of the light-induced water splitting using a standard three-electrode assembly PEC cell under 1.5 AM solar simulator. Results showed that the V2O5/BiVO4 heterojunction photoanode achieved a significantly improved photocurrent density of 1.53 mA/cm2 at 1.5 V vs Ag/AgCl, which was a 6.9-fold and a 7.3-fold improvement over the individual pristine BiVO4 (0.22 mA/cm2) and V2O5 (0.21 mA/cm2), respectively. The improvement was attributed to the lower charge resistances at the FTO/semiconductor, semiconductor/FTO and semiconductor/electrolyte interfaces as well as the fast transit time () of 6.4 ms for photo-injected electrons in the V2O5/BiVO4 heterojunction photoanode. Finally, the experimental results were used to reconstruct a theoretical band diagram in validating the heterojunction alignment between V2O5 and BiVO4 as well as in elucidating the photogenerated charge carriers transfer mechanism in the V2O5/BiVO4 heterojunction photoanode

Tuning of reduced graphene oxide thin film as an efficient electron conductive interlayer in a proven heterojunction photoanode for solar-driven photoelectrochemical water splitting

Although bismuth vanadate (BiVO4) has shown excellent photoelectrochemical (PEC) properties and is a good candidate of photoanode materials, the solar-driven PEC water splitting performance is still remained below its full potential due to the fast recombination and sluggish charge mobility of photogenerated charge carriers. Previously, we have communicated a proven Type II staggered vanadium pentoxide (V2O5)/BiVO4 heterojunction photoanode that could improve the photocurrent density. This study aimed to examine the effect of introducing an rGO thin film as an efficient electron conductive interlayer in a proven V2O5/BiVO4 heterojunction photoanode, and subsequently tuning the rGO film thickness in achieving the optimum PEC performance. The resultant ternary photoanode structure of V2O5/rGO/BiVO4 was characterised by using field emission-scanning electron microscopy (FE-SEM), high resolution-transmission electron microscopy (HR-TEM), UV–vis spectroscopy, X-ray diffractometer (XRD), Raman spectroscopy and photoluminescence (PL) measurements. Results showed that the interlayer rGO thin film arising from the sequential drop cast and electrochemical reduction of 320 μL ultrasonicated GO solution resulted in the optimal photocurrent density of 2.1 mA/cm2 at 1.5 V vs. Ag/AgCl. Furthermore, the chemical physics surrounding the photogenerated charge carrier transfer for heterojunction V2O5/BiVO4 was validated for the structure with and without the rGO interlayer. In particular, the electrochemical impedance spectroscopy (EIS) was used to measure multiple resistances at the FTO/semiconductor, semiconductor/semiconductor and semiconductor/electrolyte interfaces. Additionally, the charge transfer (Kt) and recombination (Kr) rate constants for the heterojunction V2O5/BiVO4 with the rGO interlayer were quantified using intensity modulated photocurrent spectroscopy (IMPS). Finally, the PEC H2 evolution rate from the ternary V2O5/rGO/BiVO4 photoanode was measured to be 32.7 μ mol/hr, which was about 3-fold higher than the bare V2O5/BiVO4 heterojunction photoanode

The effectiveness of intrapartum ultrasonography in assessing cervical dilatation, head station and position: A systematic review and meta-analysis

The objective of this review was to assess the effectiveness of intrapartum ultrasonography in measuring cervical dilatation, head station and position. Electronic literature searches were carried out of MEDLINE, CINAHL, and Web of Knowledge, plus manual reference list checks of all relevant articles. All published prospective studies comparing intrapartum ultrasonography with digital VE in the determination of cervical dilatation, head station and position were then evaluated for the success rate and level of agreement between ultrasonography and digital VE. Ultrasonography had higher success rate than digital VE in the determination of fetal head position, with a statistically significant difference in the first stage of labour. Second, although the successful determination of cervical dilatation was in favour of digital VE, the difference was not statistically significant. In addition, there was high agreement between ultrasound and digital VE findings on cervical dilatation. Lastly, a significant but moderate correlation between digital VE and ultrasound methods was found in the assessment of fetal head station. However, no meta-analysis could be done for the fetal head station due to the methodological differences between ultrasound anatomical landmarks and that of digital VE. The findings suggest that ultrasonography is superior to digital VE in the assessment of fetal head position, but has moderate correlation with digital VE in the assessment of head station. It also showed high agreement with digital VE in the assessment of cervical dilatation with no statistically significant difference in terms of success rate

Predictors of anemia in preschool children: Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) project.

Background: A lack of information on the etiology of anemia has hampered the design and monitoring of anemia-control efforts.Objective: We aimed to evaluate predictors of anemia in preschool children (PSC) (age range: 6-59 mo) by country and infection-burden category.Design: Cross-sectional data from 16 surveys (n = 29,293) from the Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) project were analyzed separately and pooled by category of infection burden. We assessed relations between anemia (hemoglobin concentration <110 g/L) and severe anemia (hemoglobin concentration <70 g/L) and individual-level (age, anthropometric measures, micronutrient deficiencies, malaria, and inflammation) and household-level predictors; we also examined the proportion of anemia with concomitant iron deficiency (defined as an inflammation-adjusted ferritin concentration <12 μg/L). Countries were grouped into 4 categories on the basis of risk and burden of infectious disease, and a pooled multivariable logistic regression analysis was conducted for each group.Results: Iron deficiency, malaria, breastfeeding, stunting, underweight, inflammation, low socioeconomic status, and poor sanitation were each associated with anemia in >50% of surveys. Associations between breastfeeding and anemia were attenuated by controlling for child age, which was negatively associated with anemia. The most consistent predictors of severe anemia were malaria, poor sanitation, and underweight. In multivariable pooled models, child age, iron deficiency, and stunting independently predicted anemia and severe anemia. Inflammation was generally associated with anemia in the high- and very high-infection groups but not in the low- and medium-infection groups. In PSC with anemia, 50%, 30%, 55%, and 58% of children had concomitant iron deficiency in low-, medium-, high-, and very high-infection categories, respectively.Conclusions: Although causal inference is limited by cross-sectional survey data, results suggest anemia-control programs should address both iron deficiency and infections. The relative importance of factors that are associated with anemia varies by setting, and thus, country-specific data are needed to guide programs