Avoiding Accountability: How Charter Operators Evade Ohio's Automatic Closure Law

Ohio's charter-closure law is touted as one of the toughest in the nation because it requires the automatic closure of charter schools that consistently fail to meet academic standards. The law has been showcased by the National Association of Charter School Authorizers (NACSA) in its "One Million Lives" campaign, which calls for tougher state laws to close failing charter schools.The widespread attention and support of the NACSA campaign has pushed Ohio's closure law into the spotlight as a model of accountability for low-performing charter schools. However, The Plain Dealer's editorial board, in a commentary on NACSA's praise of Ohio's charter school accountability standards, pointed out what NACSA did not: Ohio's charter school laws, while they may have stronger mandates for closure than those of other states, are still replete with loopholes. Since the charter-closure law went into effect in 2008, 20 schools across the state have met closure criteria, and all are currently listed as closed by the Ohio Department of Education (ODE). But an investigation of the schools by Policy Matters revealed that eight schools -- and the management companies that run them -- have found ways to skirt the closure law and remain open, severely undermining the law's effectiveness and highlighting the lax accountability that prevails in Ohio's charter sector. For-profit managers -- the Leona Group, Mosaica Education and White Hat Management -- operate six of the reopened schools

Modeling of transpiration reduction in van Genuchten-Mualem type soils

We derive an analytic expression for the matric flux potential (M) for van Genuchten-Mualem (VGM) type soils which can also be written in terms of a converging infinite series. Considering the first four terms of this series, the accuracy of the approximation was verified by comparing it to values of M estimated by numerical finite difference integration. Using values of the parameters for three soils from different texture classes, the proposed four-term approximation showed an almost perfect match with the numerical solution, except for effective saturations higher than 0.9. Including more terms reduced the discrepancy but also increased the complexity of the equation. The four-term equation can be used for most applications. Cases with special interest in nearly saturated soils should include more terms from the infinite series. A transpiration reduction function for use with the VGM equations is derived by combining the derived expression for M with a root water extraction model. The shape of the resulting reduction function and its dependency on the derivative of the soil hydraulic diffusivity D with respect to the soil water content theta is discussed. Positive and negative values of dD/d theta yield concave and convex or S-shaped reduction functions, respectively. On the basis of three data sets, the hydraulic properties of virtually all soils yield concave reduction curves. Such curves based solely on soil hydraulic properties do not account for the complex interactions between shoot growth, root growth, and water availabilit

Anaerobic membrane bioreactors: Are membranes really necessary?

Membranes themselves represent a significant cost for the full scale application of anaerobic membrane bioreactors (AnMBR). The possibility of operating an AnMBR with a self-forming dynamic membrane generated by the substances present in the reactor liquor would translate into an important saving. A self-forming dynamic membrane only requires a support material over which a cake layer is formed, which determines the rejection properties of the system. The present research studies the application of self-forming dynamic membranes in AnMBRs. An AnMBR was operated under thermophilic and mesophilic conditions, using woven and non woven materials as support for the dynamic membranes. Results showed that the formation of a cake layer over the support materials enables the retention of more than 99% of the solids present in the reactor. However, only low levels of flux were achieved, up to 3 L/m2 x h, and reactor operation was unstable, with sudden increases in filtration resistance, due to excessive cake layer formation. Further fine-tuning of the proposed technology involves looking for conditions that can control effectively cake layer formatio