Can seawater desalination be a win-win fix to our water cycle?

While we increasingly turn to desalination as a secure water supply, it is still perceived as an expensive and environmentally damaging solution, affordable only for affluent societies. In this contribution, we recast desalination from one of a last resort to a far-reaching, climate change mitigating, water security solution. First, we argue that the benefits of desalination go beyond the single-use value of the water produced. If coupled with water reuse for irrigation, desalination reduces groundwater abstraction and augments the water cycle. As such, it may support both adaptation to, and mitigation of climate change impacts by deploying plentiful water for human use, with all the benefits that entails, while helping preserve and restore ecosystems. Second, we counter two arguments commonly raised against desalination, namely its environmental impact and high cost. The environmental impact can be fully controlled so as not to pose long-term threats, if driven by renewable energy. Desalination may then have a zero carbon footprint. Moreover, appropriately designed outfalls make the disposal of brine at sea compatible with marine ecosystems.. Recovery of energy, minerals and more water from brine reject (particularly in the form of vapour for cooling to enable more crops and vegetation to grow), while possible, is often hardly economically justified. However, resource recovery may become more attractive in the future, and help reduce the brine volumes to dispose of. When fresh water becomes scarce, its cost tends to go up, making desalination increasingly economic. Moreover, desalination can have virtually no environmental costs. Considering the environmental costs of over-abstraction of freshwater, desalination tilts the balance in its favour.

Surgery of recurrent parastomal hernia: direct repair or relocation?

PURPOSE: Parastomal hernia is a common late complication after stoma creation. The management options are many; unfortunately, most literature suggests unsatisfactory results. There are few studies comparing the outcomes after repair of parastomal hernias especially in recurrent cases, and the results are controversial. The aim of this study was to compare outcomes after repair of recurrent parastomal hernias between direct repair (DR) and relocation (RL). METHOD: We performed a retrospective chart review of patients who underwent direct repair or RL for recurrent parastomal hernia during the period between 1990 and 2005. Perioperative data and re-recurrence rates were obtained and analysed with appropriate statistical methods. RESULTS: With mean follow-up time of 2 years, 50 operations were available for evaluation; 27 (54%) DR and 23 (46%) RL [five same-side RL (SSRL) and 18 opposite-side RL (OSRL)]. There were no deaths and there were similar complication rates between groups. Four of five (80%) SSRL had a re-recurrent parastomal hernia. Considering only DR with OSRL, although OSRL had longer operative time and hospital stay than DR, the re-recurrence rate was lower (38%vs 74%; P = 0.02). However, with Kaplan-Meier calculated and longer predicted follow-up time, re-recurrence rates were similar (Log rank P = 0.09). CONCLUSION: Recurrent parastomal hernia repair is associated with high re-recurrence rates.OSRL seems to have promising short-term outcomes; however, whether these results hold up long-term remains unclear. Therefore, larger cohorts of patients with longer follow-up or prospective randomized trials are needed.

Seasonal differences in SO2 ground-level impacts from a power plant plume on complex terrain.

The objective of this study is to describe the seasonal differences in SO2 ground-level fumigations from a power plant situated on very complex terrain in the Iberian Peninsula within the Western Mediterranean Basin (WMB). The study area extends more than 80 km around the power plant on very complex semi-arid terrain. Considering different plume-rise schemes, by experimentation and modelling this study attempts to characterise the seasonal differences in both the plume footprint 80 km around the power plant and the turbulent regime (diurnal or nocturnal) driving the main contribution to the accumulated plume footprints at different distances from the power plant within a complex terrain region. Two markedly different SO2 ground-level distributions around the power plant are presented for the typical summer and winter dispersive scenarios in the area. Simulations show that the SO2 footprint of a plume being advected more than 450 m above ground level in complex terrain is highly dependent on the prevailing meteorological conditions and on the mesoscale perturbations of the synoptic flows within the lower layers of the troposphere. The results obtained show how on complex terrain, despite seasonal meteorological differences and under stable dispersive conditions, the simulated mechanical turbulence leeward of the mountain ranges reproduces highly concentrated SO2 fumigations on the ground more than 50 km away from the power plant. Besides, under summer convective activity, plume fumigations have been successfully simulated less than 15 km from the power plant. In conclusion, this study shows how measurements from air quality networks together with information obtained from atmospheric transport and diffusion models are able to characterise different transport scenarios. This is a clear advantage for the end-users and decision-makers who manage and optimise the regional air quality networks.

Revaluación de la versión española del cuestionario diabetes quality of life (EsDQOL) / Reappraisal of the spanish version of the diabetes quality of life questionnaire (EsDQOL)

A lo largo de varios años hemos adaptado y mejorado1-5 la versión en español del Diabetes Quality of Life Questionnaire (EsDQOL), lo que nos ha permitido conseguir suficiente experiencia en su aplicación. Teniendo en cuenta que este proceso de adaptación ha sido dinámico y, por tanto, sujeto a modificaciones y revisiones, creemos procedente en el momento actual, sobre la base de nuestros resultados, proponer algunas modificaciones que pueden incrementar la fiabilidad y aplicación de la versión española del DQOL (AU)

Atmospheric nitrogen deposition on the east coast of Spain: relevance of dry deposition in semi-arid Mediterranean regions.

Bulk deposition composition and pine branch washing were measured from April 1999 to March 2000 on the east coast of Spain. The main objective was to characterise N deposition patterns with special emphasis on dry deposition. Bulk deposition in the region is dominated by neutralisation processes by Ca2+ and HCO3-, ClNa of marine origin and a high correlation between NO3- and SO4(2-). SO4(2-) concentrations show a decrease with respect to previous studies in the region in agreement with generalized sulfur emission decreases while the remaining ions, including NO3-, are higher due to their general increase as well as to the inclusion of dry deposition in bulk collectors in the present study. An enrichment in NO3- has been observed in dry deposition composition branch washing) with respect to bulk deposition, while an impoverishment has been observed in the case of NH4+. Annual bulk deposition varies between 7.22-3.1 and 3.5-1.8 Kg ha(-1) year(-1) for S- SO4(2-) and N- NO3-, respectively. N total deposition goes from 9.78 to 6.8 Kg ha(-1) year(-1) at most stations, with the lowest deposition at the control station and Alcoi. The relative dry deposition with respect to the total was over 40% at most stations, going up to 75% at the southern station. N-deposition is expected to be higher considering that N-NH4+ deposition has been underestimated in this study.

[Analysis of the experience of diabetes mellitus through case study: an approach to patient's quality of life]. / Análisis de la vivencia de la diabetes mellitus a través del estudio de casos: una aproximación a la calidad de vida del paciente.

BACKGROUND: To assess how patients with diabetes experience their condition. PATIENTS AND METHOD: Pilot study conducted in 10 selected patients with type 1 diabetes. A structured interview guide was prepared including physical, social and emotional areas. The information provided was analyzed qualitatively, key statements were coded in analysis units and processed using the computer program Ethnograph. RESULTS: Conceptual maps show that this group of patients: a) Do not feel physically limited but they need a constant planning of every aspect of their lives; b) they avoid openly manifesting their condition, they perceive discrimination at work and little social awareness, and c) except for survival skills, they primarily learn about their disease and its management through their own experience. CONCLUSION: This qualitative research method allows for the application of these observations to different groups within similar problems and contexts.

Lumbar and lumbosacral fusions using Cotrel-Dubousset pedicle screws and rods.

The first 50 consecutive patients stabilized with Cotrel-Dubousset rods for lumbar or lumbosacral fusions were followed for an average of 2 years. The occurrence of fusion, maintenance of alignment, and rate of hardware complications were examined. There were 28 men and 22 women, ages 18-87 years, and 133 vertebral levels. Twenty-nine sets of 5-mm, and 21 pairs of 7-mm, rods were placed. Two hundred and sixty-eight pedicle screws were used. Forty-eight out of 50 (96%) patients demonstrated successful arthrodesis after their initial procedure. One pedicle screw became separated from the rod. No rods migrated or broke. Seven (2.6%) pedicle screws bent and 3 (1%) broke. Large and small diameter Cotrel-Dubousset rods allowed short segment lumbar and lumbosacral fusion with a high degree of reliability.

The effect of marker placement deviations on spinal range of motion determined by video motion analysis.

BACKGROUND AND PURPOSE: Spinal range of motion (ROM) is an important indicator of spinal function and is used in the determination of disability and compensation. One technology that has been used to assess spinal ROM is video motion analysis. No studies, however, have been done to investigate the effects of marker placement on ROM. The purpose of this study was to investigate the effect of deviations in reflective marker placement on ROM measurements obtained via video motion analysis. METHODS: A model of the spine was constructed and used to obtain ROM measurements from three segments of the model to isolate error from marker placement without the confounding effects of subject error. A standard placement and six altered placements were used to determine the effect of moving reflective markers on ROM. RESULTS: Results indicated statistically significant effects of marker placement for a number of flexion/extension and lateral side-bending ROM measurements. When the mean differences were compared with data obtained in human test-retest studies with the same equipment, the differences from a 2.5-cm marker deviation did not appear to be clinically meaningful. CONCLUSION AND DISCUSSION: We conclude that small marker deviations (2.5 cm) are not likely to adversely affect clinical information obtained when using this type of apparatus.

Lateral parascapular extrapleural approach to the upper thoracic spine.

The upper thoracic vertebrae are difficult to approach surgically because of the narrowing of the thoracic inlet, the proximity of the brachial plexus, and the parascapular shoulder musculature. A novel lateral parascapular extrapleural approach to the upper thoracic vertebrae is described. The parascapular shoulder musculature (trapezius, levator scapulae, and rhomboid muscles) is reflected off the spinous processes to the scapula as a musculocutaneous flap, preserving the neurovascular supply. The paraspinal musculature is mobilized and retracted, and the upper dorsal ribs are removed with caution to avoid injury to the C-8 and T-1 nerve roots. The rami communicantes are transected, and the sympathetic chain is displaced anterolaterally. The T2-4 vertebrae can be approached unobstructed. The T-1 nerve root obstructs posterolateral access to the T-1 vertebra, necessitating an inferolateral approach underneath the T-1 nerve root axilla. Four patients with compressive myelopathy from upper thoracic vertebral metastases underwent neural decompression, vertebral reconstruction, and posterior spinal fixation with this approach. Their postoperative neurological status was either unchanged or improved. Complications included radiographic pleural effusion and superficial wound dehiscence; one patient required posterior spinal reinstrumentation for progressive kyphosis. One patient developed pneumonia 7 days postoperatively which was unresponsive to appropriate treatment. It is believed that the anatomical limitations to this region have been overcome, and that excellent exposure of the T1-4 vertebrae for neural decompression and vertebral reconstruction can be performed safely. A major advantage is that posterior spinal fixation can be carried out simultaneously.