Biological ion exchange as an alternative to biological activated carbon for natural organic matter removal: Impact of temperature and empty bed contact time (EBCT)

Biofiltration is a widely used process in drinking water treatment plants to remove natural organic matter (NOM). A novel biofiltration process using ion exchange resins as supporting media (i.e., biological ion exchange or BIEX) has been demonstrated to provide a superior performance compared to conventional biological activated carbon (BAC). In order to optimize the performance of BIEX filters, the impact of temperature and empty bed contact time (EBCT) on NOM removal was systematically studied. In the present study, bench-scale BIEX filters were set up in parallel with BAC filters and operated at different temperatures (i.e., 4 °C, 10 °C and 20 °C) and EBCTs (i.e., 7.5 min, 15 min and 30 min). Higher average dissolved organic carbon (DOC) removal was achieved in BIEX filters (73 ± 6%) than BAC filters (22 ± 9%) at the steady state with an EBCT of 30 min. Higher temperatures improved NOM removal in both BAC and BIEX filters, with the impact being greater at lower EBCTs (i.e., 7.5 min and 15 min). Higher EBCTs could also improve NOM removal, with the impact being greater at lower temperatures (i.e., 4 °C and 10 °C). DOC removal for BIEX and BAC filters can be modeled with a first-order kinetic model (R² = 0.93-0.99). BAC had a higher temperature activity coefficient than BIEX (1.0675 vs. 1.0429), indicating that temperature has a greater impact on BAC filtration than BIEX filtration. Overall, temperature and EBCT must be considered simultaneously for biofilters to efficiently remove NOM.

Is Digital Animation Superior to Text Resources for Facial Transplantation Education? A Randomized Controlled Trial

BACKGROUND

Facial transplantation is a complex surgical procedure that requires education of medical professionals, patients, and the general public. The objective of this randomized controlled trial was to compare the educational efficacy of facial transplantation digital animation versus text resources for teaching medical students a complex surgical procedure and its applicable anatomical and surgical principles.

METHODS

Medical student volunteers were recruited and prospectively randomized to an animation or a text group. Students completed preintervention and postintervention assessments of confidence and knowledge of head and neck anatomy and facial transplantation. Student Evaluations of Educational Quality survey assessed student satisfaction with both tools following study crossover. Knowledge assessment was developed using National Board of Medical Examiners guidelines and content validated by four experts. The Cohen d statistic was used to measure the effect size of each intervention.

RESULTS

Thirty-six students were assigned randomly to the animation group (n = 19) or the text (n = 17) group. Postintervention analysis demonstrated significantly higher performance scores in the animation group compared to the text group (p = 0.029). The animation group had a larger effect size (Cohen d = 1.96 versus 1.27). Only students in the animation group reported significantly improved confidence in head and neck anatomy after the intervention (p = 0.002). Both groups demonstrated significantly increased postintervention confidence in knowledge of facial transplantation (p < 0.001). Satisfaction scores revealed that students significantly favored the animation resource (p < 0.001).

CONCLUSIONS

Animation can be an effective tool for facial transplantation education and results in improved student knowledge, confidence, and satisfaction compared to text resources. Facial transplantation can also be used as an educational framework for teaching medical students anatomical and surgical principles.

Development and economic trends in anticancer drugs licensed in the UK from 2015 to 2019

Analysis of new anticancer drugs licensed in the UK found that 44 new therapies were approved from 2015 to 2019. No other 5-year period has produced as many new therapies. Most new drugs are kinase inhibitors (KIs, N=18) and monoclonal antibodies (mAbs, N=16) with only one classical cytotoxic chemotherapy (CC) licensed. The average median treatment duration has risen by 55 days to 318 days (263 days in 2010-2014). Drug costs have escalated; an average treatment course now costs £62 343, compared to £35 383 in 2010-2014. New drugs are delivering significant clinical benefits with longer treatment durations. However, the financial burden is greater, heralding economic challenges for healthcare providers.

Have We Achieved Optimal Skin Color Matching in Partial Facial Transplantation? A Survey Study of the General Public and Medical Professionals

BACKGROUND

Skin color matching is an essential factor in achieving optimal aesthetic outcome in partial facial transplantation. However, there is no published literature evaluating the success of color matching to date. Furthermore, a medical professional's perception of an optimal color match may not necessarily translate to that of the general public. The purpose of our study was to evaluate skin color matching between the donor allograft and recipient native tissue in partial facial transplantations to determine the level of success perceived by the general public and medical professionals.

METHODS

Published photographs of partial face transplant recipients were used to create a survey where recipient native and donor allograft skin samples were juxtaposed. Thirty-three members of the general public and 30 medical professionals were asked to rate skin color match on a scale from "excellent match" to "not a match."

RESULTS

Overall, 47% of given ratings were positive, indicating an "excellent" or "good match," and 53% of ratings were negative, indicating a "poor match" or "lack of match" between the skin sample pairings shown. Of the 19 partial face transplant patients who were rated, 9 patients received >50% positive ratings, and 10 patients received <50% positive ratings. Medical professionals consistently gave more positive ratings, with statistically significant differences in 7 of the 19 rated patients (P < 0.05).

CONCLUSION

The results suggest that there is need for improvement in color matching in partial facial transplantation, and that the general public is more critical of skin color matching compared to medical professionals.

A survey exploring ophthalmologists' attitudes and beliefs in performing Immediately Sequential Bilateral Cataract Surgery in the United Kingdom

BACKGROUND

The standard approach to treat cataracts is Delayed Sequential Bilateral Cataract Surgery (DSBCS), during which patients have a separate operation date for each eye. An alternative method of delivery is Immediately Sequential Bilateral Cataract Surgery (ISBCS). The aim of this project was to examine the attitudes and beliefs of UK ophthalmologists towards ISBCS, explore their reasons to either practise or not practise ISBCS and identify barriers hindering its implementation in the UK.

METHODS

A questionnaire was distributed to consultant members of The Royal College of Ophthalmologists (RCOphth, UK) and collected electronically. An initial screening question in regards to prior experience with ISBCS directed the rest of the survey; participants were asked to rate the importance of several factors with regards to performing ISBCS. Free text options were also available. Descriptive analysis was subsequently performed.

RESULTS

Of the 1357 recipients, 130 (9.6%) ophthalmologists completed the survey. Of those, 13.9% were currently performing ISBCS, 83.1% had never performed, and 3.1% had previously done so but since stopped. The main factors that acted as barriers were lack of: (1) College approval (20.5%); (2) medico-legal approval (20.2%); (3) evidence to support the use of ISBCS (16.0%); and (4) hospital approval (13.3%). Additionally, the perceived risk of complications for patients played an important role when considering ISBCS, with the risk of endophthalmitis being most feared.

CONCLUSIONS

This survey demonstrates some of the barriers that prevent ophthalmologist's performing ISBCS in the UK. There is a need for further exploration in this field to evaluate the effect of addressing any of these concerns on the implementation of ISBCS.

Forest elephant movement and habitat use in a tropical forest-grassland mosaic in Gabon

Poaching of forest elephants (Loxodonta cyclotis) for ivory has decimated their populations in Central Africa. Studying elephant movement can provide insight into habitat and resource use to reveal where, when, and why they move and guide conservation efforts. We fitted 17 forest elephants with global positioning system (GPS) collars in 2015 and 2016 in the tropical forest-grassland mosaic of the Wonga Wongué Presidential Reserve (WW), Gabon. Using the location data, we quantified movement distances, home ranges, and habitat use to examine the environmental drivers of elephant movements and predict where elephants occur spatially and temporally. Forest elephants, on average, traveled 2,840 km annually and had home ranges of 713 km², with males covering significantly larger home ranges than females. Forest elephants demonstrated both daily and seasonal movement patterns. Daily, they moved between forest and grassland at dawn and dusk. Seasonally, they spent proportionally more time in grassland than forest during the short-wet season when grasses recruit. Forest elephants also traveled faster during the short-wet season when fruit availability was greatest, likely reflecting long, direct movements to preferred fruiting tree species. Forest elephants tended to select areas with high tree and shrub density that afford cover and browse. When villages occurred in their home ranges elephants spent a disproportionate amount of time near them, particularly in the dry season, probably for access to agricultural crops and preferred habitat. Given the importance of the grassland habitat for elephants, maintenance of the forest-grassland matrix is a conservation priority in WW. Law enforcement, outreach, and education should focus on areas of potential human-elephant conflict near villages along the borders of the reserve. GPS-tracking should be extended into multi-use areas in the peripheries of protected areas to evaluate the effects of human disturbance on elephant movements and to maintain connectivity among elephant populations in Gabon.

Oronasopharyngeal suction versus wiping of the mouth and nose at birth: a randomised equivalency trial

BACKGROUND

Wiping of the mouth and nose at birth is an alternative method to oronasopharyngeal suction in delivery-room management of neonates, but whether these methods have equivalent effectiveness is unclear.

METHODS

For this randomised equivalency trial, neonates delivered at 35 weeks' gestation or later at the University of Alabama at Birmingham Hospital, Birmingham, AL, USA, between October, 2010, and November, 2011, were eligible. Before birth, neonates were randomly assigned gentle wiping of the face, mouth (implemented by the paediatric or obstetric resident), and nose with a towel (wipe group) or suction with a bulb syringe of the mouth and nostrils (suction group). The primary outcome was the respiratory rate in the first 24 h after birth. We hypothesised that respiratory rates would differ by fewer than 4 breaths per min between groups. Analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT01197807.

FINDINGS

506 neonates born at a median of 39 weeks' gestation (IQR 38-40) were randomised. Three parents withdrew consent and 15 non-vigorous neonates with meconium-stained amniotic fluid were excluded. Among the 488 treated neonates, the mean respiratory rates in the first 24 h were 51 (SD 8) breaths per min in the wipe group and 50 (6) breaths per min in the suction group (difference of means 1 breath per min, 95% CI -2 to 0, p<0·001).

INTERPRETATION

Wiping the nose and mouth has equivalent efficacy to routine use of oronasopharyngeal suction in neonates born at or beyond 35 weeks' gestation.

FUNDING

None.

Systematic review: the potential influence of mesalazine formulation on maintenance of remission in Crohn's disease

AIM

To evaluate the effectiveness of pH 6-/pH 7-dependent and controlled-release mesalazines in maintaining medically and surgically induced Crohn's disease remission.

METHODS

A systematic search identified 13 randomized controlled trials (RCTs). The rate of symptomatic relapse (Crohn's disease activity index >150, or an increase in baseline by at least 60-100 points) was extracted from each randomized controlled trial. Pooled odds ratios (OR), the number needed to treat (NNT), and percentage therapeutic benefit (absolute risk reduction) were calculated.

RESULTS

Treatment with pH 7-dependent mesalazine significantly reduced the risk of relapse in patients with either surgically [OR 0.28; 95% confidence interval (CI) 0.12-0.65; P = 0.0032] or medically induced remission (OR 0.38; 95% CI 0.17-0.85; P = 0.0113). However, treatment with controlled-release mesalazine and pH 6-dependent mesalazine failed to show any significant advantage over placebo. The NNT to maintain surgically or medically induced remission was lowest for pH 7-dependent mesalazine (NNT = 4 and 5, respectively; NNT = 15 and 16 for controlled-release mesalazine and NNT = 11 and 23 for pH 6-dependent mesalazine). Therapeutic benefit was highest for pH 7-dependent mesalazine (surgical = 30.6%, medical = 22.8%). This compared with 6.9% (surgical) and 6.4% (medical) for controlled-release mesalazine, and 9.8% and 4.4%, respectively, for pH 6-dependent mesalazine.

CONCLUSION

Further trials of pH 7-dependent mesalazine formulations are warranted in the maintenance of remission in Crohn's disease.