Tailoring hierarchical structures in cellulose carbon aerogels from sugarcane bagasse using different crosslinking agents for enhancing electrochemical desalination capability.

Sugarcane bagasse is one of the most common Vietnamese agricultural waste, which possesses a large percentage of cellulose, making it an abundant and environmentally friendly source for the fabrication of cellulose carbon aerogel. Herein, waste sugarcane bagasse was used to synthesize cellulose aerogel using different crosslinking agents such as urea, polyvinyl alcohol (PVA) and sodium alginate (SA). The 3D porous network of cellulose aerogels was constructed by intermolecular hydrogen bonding, which was confirmed by Fourier transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and nitrogen adsorption/desorption. Among the three cellulose aerogel samples, cellulose - SA aerogel (SB-CA-SA) has low density of 0.04 g m-3 and high porosity of 97.38%, leading to high surface area of 497.9 m2 g-1 with 55.67% micropores of activated carbon aerogel (SB-ACCA-SA). The salt adsorption capacity was high (17.87 mg g-1), which can be further enhanced to 31.40 mg g-1 with the addition of CNT. Moreover, the desalination process using the SB-ACCA-SA-CNT electrode was stable even after 50 cycles. The results show the great combination of cellulose from waste sugarcane bagasse with sodium alginate and carbon nanotubes in the fabrication of carbon materials as the CDI-utilized electrodes with high desalination capability and good durability.

Clinical outcomes of pediatric macular edema associated with non-infectious uveitis.

BACKGROUND: Macular edema (ME) is the most frequent cause of irreversible visual impairment in patients with uveitis. To date, little data exists about the clinical course of ME in pediatric patients. A retrospective, observational study was performed to examine the visual and macular thickness outcomes of ME associated with chronic, noninfectious uveitis in pediatric patients. METHODS: Pediatric patients with noninfectious uveitis complicated by ME seen in the University of California San Francisco Health System from 2012 to 2018 were identified using ICD-9 and ICD-10 codes. Data were collected from medical records including demographics, diagnoses, ocular history, OCT imaging findings, complications, and treatments at first encounter and at 3, 6, 9, and 12-month follow-up visits. Cox proportional hazards regression was used to investigate the association between different classes of treatment (steroid drops, steroid injections, oral steroids and other immunosuppressive therapies) and resolution of macular edema. RESULTS: The cohort comprised of 21 children (26 eyes) with a mean age of 10.5 years (SD 3.3). Undifferentiated uveitis was the most common diagnosis, affecting 19 eyes (73.1%). The majority of observed macular edema was unilateral (16 patients, 76.2%) and 5 patients had bilateral macular edema. The mean duration of follow-up at UCSF was 35.3 months (SD 25.7). By 12 months, 18 eyes (69.2%) had achieved resolution of ME. The median time to resolution was 3 months (IQR 3-6 months). Median best-corrected visual acuity (BCVA) at baseline was 0.54 logMAR (Snellen 20/69, IQR 20/40 to 20/200). Median BCVA at 12 months was 0.1 logMAR (Snellen 20/25, IQR 20/20 to 20/50) Corticosteroid injections were associated with a 4.0-fold higher rate of macular edema resolution (95% CI 1.3-12.2, P = 0.01). CONCLUSIONS: Although only 15% of the pediatric patients with uveitis in the study cohort had ME, it is clinically important to conduct OCTs to detect ME in this population. Treatment resulted in 69% of eyes achieving resolution of ME by 12 months, accompanied with improvement in visual acuity. Corticosteroid injections were significantly associated with resolution of macular edema.

Association Between Arterial Blood Gas Variation and Intraocular Pressure in Healthy Subjects Exposed to Acute Short-Term Hypobaric Hypoxia.

PURPOSE: To investigate the association between changes in arterial blood gases and intraocular pressure (IOP) after acute, short-term exposure to simulated elevation of 4000 m above sea level. METHODS: Twenty-five healthy young lowlanders participated in this prospective study. IOP was measured in both eyes with an Accupen tonometer. Arterial blood gas parameters (partial oxygen pressure [PaO2], partial carbon dioxide pressure [PaCO2], pH, and bicarbonate ion [HCO3 -]) were checked using a blood gas analyzer. Measurements were taken at sea level (T1), at 15-minute (T2) and at 2-hour (T3) exposure times to simulated 4000 m above sea level in a hypobaric chamber, and upon return to sea level (T4). Associations between arterial blood gas parameters and IOP were evaluated using multivariate linear regression. RESULTS: PaO2 significantly decreased at T2 and T3, resolving at T4 (P < 0.001). pH significantly increased at T2 and returned to baseline at T3 (P = 0.004). Actual and standard bicarbonate ion both dropped with IOP at T3 and T4. IOP significantly decreased from 16.4 ± 3.4 mm Hg at T1 to 15.1 ± 2.1 mm Hg (P = 0.041) at T3 and remained lower (14.9 ± 2.4 mm Hg; P = 0.029) at T4. IOP was not correlated with pH. Multivariate linear regression showed that lower IOP was associated with lower standard bicarbonate ion (beta = -1.061; 95% confidence interval, -0.049 to -2.074; P = 0.04) when adjusted for actual bicarbonate and diastolic blood pressure. CONCLUSIONS: Hypobaric hypoxia triggers plasma bicarbonate ion reduction which, rather than pH, may decrease aqueous humor formation and subsequently cause IOP reduction. These findings may shed light on the mechanism of IOP regulation at high altitude. TRANSLATIONAL RELEVANCE: Hypoxia-triggered reduction in plasma bicarbonate ion may decrease aqueous humor production, leading to IOP reduction at high altitude. These findings may provide new insight into a potential mechanism of IOP regulation. Hypobaric hypoxia at high altitude is an environmental factor that can reduce IOP and, therefore, deserves further study.