An ecohydrological journey of 4500 years reveals a stable but threatened precipitation-groundwater recharge relation around Jerusalem.
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ABSTRACT:
SUBMITTER: Fatichi S
PROVIDER: S-EPMC8442904 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:The high porosity of medium-coarse sand (MCS) layers in groundwater recharge areas presents a high environmental risk. Sulfamethoxazole (SMX) and trimethoprim (TMP) are two common sulfonamide antibiotics in surface water that have a high propensity to migrate into groundwater. In this study, four biochars were prepared and biochar-amended soil aquifer treatment (SAT) columns were constructed to remove SMX and TMP. Batch experiments demonstrated that the sorption isotherms conformed to the Freundlich model. The maximum adsorptions of biochars prepared at 700 °C were 54.73 and 67.62 mg/g for SMX and 59.3 and 73.38 mg/g for TMP. Electrostatic interaction may be one of the primary mechanisms of adsorption. The column experiments showed that the SMX and TMP removal rate of the biochar-amended SAT was as high as 96%, while that of the MCS SAT was less than 5%. The addition of biochar greatly improved the retention capacity of the pollutants in the MCS layer in the groundwater recharge area and effectively reduced environmental risk.
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Project description:ObjectiveAlthough shorter time to pediatric resective epilepsy surgery is strongly associated with greater disease severity, other nonclinical diagnostic and sociodemographic factors also play a role. We aimed to examine parent-reported barriers to timely receipt of pediatric epilepsy surgery.MethodsWe conducted 37 interviews of parents of children who previously had resective epilepsy surgery at University of California Los Angeles (UCLA; 2006-2011). Interviews were audio-recorded, transcribed, and systematically coded using thematic analysis by two independent coders, and subsequently checked for agreement. Clinical data, including "time to surgery" (age of epilepsy onset to surgery) were abstracted from medical records.ResultsThe mean time to surgery was 5.3 years (standard deviation [SD] 3.8); surgery types included 32% hemispherectomy, 43% lobar/focal, and 24% multilobar. At surgery, parents were on average 38.4 years (SD 6.6) and children were on average 8.2 years (SD 4.7). The more arduous and longer aspect of the journey to surgery was perceived by parents to be experienced prior to presurgical referral. The time from second antiepileptic drug failure to presurgical referral was ≥ 1 year in 64% of children. Thematic analysis revealed four themes (with subthemes) along the journey to surgery and beyond: (1) recognition--"something is wrong" (unfamiliarity with epilepsy, identification of medical emergency); (2) searching and finding--"a circuitous journey" (information seeking, finding the right doctors, multiple medications, insurance obstacles, parental stress); (3) surgery is a viable option--"the right spot" (surgery as last resort, surgery as best option, hoping for candidacy); and (4) life now--"we took the steps we needed to" (a new life, giving back).SignificanceMultipronged interventions targeting parent-, provider-, and system-based barriers should focus on the critical presurgical referral period; such interventions are needed to remediate delays and improve access to subspecialty care for children with medically refractory epilepsy and potentially eligible for surgery.
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