Linking Water Quality to Drinking Water Treatment Costs Using Time Series Analysis: Examining the Effect of a Treatment Plant Upgrade in Ohio.

We estimate a cost function for a water treatment plant in Ohio to assess the avoided-treatment costs resulting from improved source water quality. Regulations and source water concerns motivated the treatment plant to upgrade its treatment process by adding a granular activated carbon building in 2012. The cost function uses daily observations from 2013 to 2016; this allows us to compare the results to a cost function estimated for 2007-2011 for the same plant. Both models focus on understanding the relationship between treatment costs per 1,000 gallons (per 3.79 m3) of produced drinking water and predictor variables such as turbidity, pH, total organic carbon, deviations from target pool elevation, final production, and seasonal variables. Different from the 2007-2011 model, the 2013-2016 model includes a harmful algal bloom toxin variable. We find that the new treatment process leads to a different cost model than the one that covers 2007-2011. Both total organic carbon and algal toxin are important drivers for the 2013-2016 treatment costs. This reflects a significant increase in cyanobacteria cell densities capable of producing toxins in the source water between time periods. The 2013-2016 model also reveals that positive and negative shocks to treatment costs affect volatility, the changes in the variance of costs through time, differently. Positive shocks, or increased costs, lead to higher volatility compared to negative shocks, or decreased costs, of similar magnitude. After quantifying the changes in treatment costs due to changes in source water quality, we discuss how the study results inform policy-relevant decisions.

Endoscopic endonasal skull base surgery during the COVID-19 pandemic: A developing country perspective.

BACKGROUND: Although primarily a respiratory disorder, the coronavirus pandemic has paralyzed almost all aspects of health-care delivery. Emergency procedures are likely continuing in most countries, however, some of them raises certain concerns to the surgeons such as the endoscopic endonasal skull base surgeries. The aim of this study is to present the current situation from a developing country perspective in dealing with such cases at the time of the COVID-19 pandemic. METHODS: A cross-sectional analytical survey was distributed among neurosurgeons who performed emergency surgeries during the COVID-19 pandemic in Cairo, Egypt, between May 8, 2020, and June 7, 2020. The survey entailed patients' information (demographics, preoperative screening, and postoperative COVID-19 symptoms), surgical team information (demographics and postoperative COVID-19 symptoms), and operative information (personal protective equipment [PPE] utilization and basal craniectomy). RESULTS: Our survey was completed on June 7, 2020 (16 completed, 100% response rate). The patients were screened for COVID-19 preoperatively through complete blood cell (CBC) (100%), computed tomography (CT) chest (68.8%), chest examination (50%), C-reactive protein (CRP) (50%), and serological testing (6.3%). Only 18.8% of the surgical team utilized N95 mask and goggles, 12.5% utilized face shield, and none used PAPRs. Regarding the basal craniectomy, 81.3% used Kerrison Rongeur and chisel, 25% used a high-speed drill, and 6.3% used a mucosal shaver. None of the patients developed any COVID-19 symptoms during the first 3 weeks postsurgery and one of the surgeons developed high fever with negative nasopharyngeal swabs. CONCLUSION: In developing countries with limited resources, preoperative screening using chest examination, CBC, and CT chest might be sufficient to replace Reverse transcription polymerase chain reaction. Developing countries require adequate support with screening tests, PPE, and critical care equipment such as ventilators.

Syringomyelia associated with cervical spondylotic myelopathy causing canal stenosis. A rare association.

BACKGROUND: Although cervical spondylosis is extremely common, only few cases with associated syrinx have been reported. Depending on review of two large data bases, we report this case series. In addition, we evaluated the posterior decompression as the management option in treatment of this rare condition. MATERIALS AND METHODS: Data of all cases with cervical spondylosis and canal stenosis that sought medical advice or needed decompressive laminectomy/laminoplasty between the years 2006 and 2015 were checked in manually. Perioperative data, together with follow up were reviewed. RESULTS: Out of five cases found in the reviewed data; four cases undergone posterior decompression (laminectomy in two cases and laminoplasty in the other). One case refused surgery. Along mean follow up period of 6.25 months; three cases improved markedly, while in one case no improvement occurred. CONCLUSION: Cervical spondylotic myelopathy can rarely cause syringomyelia. Posterior decompression would be the preferable management option with clinical improvement of most of the cases.

Surgical resection of low-grade gliomas in eloquent areas with the guidance of the preoperative functional magnetic resonance imaging and craniometric points.

OBJECTIVES: Surgical resection of low-grade gliomas (LGGs) in eloquent areas is one of the challenges in neurosurgery, using assistant tools to facilitate effective excision with minimal postoperative neurological deficits has been previously discussed (awake craniotomy and intraoperative cortical stimulation); however, these tools could have their own limitations thus implementation of a simple and effective technique that can guide to safe excision is needed in many situations. MATERIALS AND METHODS: The authors conducted a retrospective analysis of a prospectively collected data of 76 consecutive surgical cases of LGGs of these 21 cases were situated in eloquent areas. Preoperative functional magnetic resonance imaging (fMRI), pre- and post-operative MRI with volumetric analysis of the tumor size was conducted, and intraoperative determination of the craniometric points related to the tumor (navigation guided in 10 cases) were studied to evaluate the effectiveness of the aforementioned tools in safe excision of the aforementioned tumors. RESULTS: Total-near total excision in 14 (66.67%) subtotal in 6 (28.57%), and biopsy in 1 case (4.57%). In long-term follow-up, only one case experienced persistent dysphasia. CONCLUSION: In spite of its simplicity, the identification of the safe anatomical landmarks guided by the preoperative fMRI is a useful technique that serves in safe excision of LGGs in eloquent areas. Such technique can replace intraoperative evoked potentials or the awake craniotomy in most of the cases. However, navigation-guided excision might be crucial in deeply seated and large tumors to allow safe and radical excision.

Illumination of dense urban areas by light redirecting panels.

With the high population growth rate, especially in developing countries, and the scarcity of land resources, buildings are becoming so close to each other, depriving the lower floors and the alleys from sunlight and consequently causing health problems. Therefore, there is an urgent need for cost-effective efficient light redirecting panels that guide sun rays into those dim places. In this paper, we address this problem. A novel sine wave based panel is presented to redirect/diverge light downward and enhance the illumination level in those dark places. Simulation results show that the proposed panel improves the illuminance values by more than 200% and 400% in autumn and winter respectively, operates over wide solar altitude ranges, and redirects light efficiently. Experimental and simulation results are in good agreement.

Penile advancement and lengthening for the management of post-circumcision traumatic short penis in adolescents.

OBJECTIVES: To report on the safety of combing suprapubic fat liposuction, penile suspensory ligament severing, and Z-plasty of penoscrotal webbing for penile lengthening in cases of post-circumcision traumatic short penis in adolescents. METHODS: This prospective study was conducted in 9 male patients with a mean age of 15.6 ± 1.4 years. All patients had a short penis because of traumatic amputation of the glans in 7 patients and both glanular and partial distal corporal loss in 2 patients during circumcision. All were initially treated in childhood by penile skin advancement for phallic coverage. Penile length and circumference were measured pre- and post-operatively, both in the flaccid state at maximal stretch and in the erect state. Operative technique included Z-plasty of penoscrotal web, release of suspensory ligament, and suprapubic fat liposuction. RESULTS: Average functional penile length measured 3 months post-operatively had significantly increased by 18-30 mm (mean: 23 ± 4 mm) in the provoked, erect state. All patients had normally developed penile corpora cavernosa and wide circumference (mean: 11.7 ± 0.2 cm). No post-operative complications occurred in any of the patients. No patients had sexual partners or were sexually active. CONCLUSIONS: The described technique of penile advancement and lengthening can be safely applied to patients with post-circumcision traumatic short penis.