The use of RO to remove emerging micropollutants following CAS/UF or MBR treatment of municipal wastewater

The removal of various organic micropollutants (OMPs), including six antibiotics (ERY, ROX, CLA, SMX, SMZ, and TMP), three pharmaceuticals (ibuprofen, salicylic acid, and diclofenac), one industrial product (BPA), and one hormone (cholesterol), was investigated in two pilot plants treating the same raw sewage of the Tel-Aviv WWTP. The effluent production by CAS-UF was 45 m³/h while that of MBR was 40 L/h. Each system's effluent constituted the feed for its RO, which comprised three RO steps after the CAS/UF and a semi-batch RO system after the MBR. Despite significant molecular differences between the selected OMPs, high removal rates were achieved after the RO stage (> 99% for macrolides, pharmaceuticals, cholesterol, and BPA, 95% for diclofenac, and > 93% removal of sulfonamides). However, low antibiotics concentrations and 28–223 ng/L residuals of ibuprofen, diclofenac, salicylic acid, cholesterol, and BPA in the MBR/RO and CAS-UF/RO permeates showed that although RO is an efficient removal solution, it cannot serve as an absolute barrier to OMPs. Therefore, additional treatment techniques should be considered to be incorporated aside the RO to ensure complete removal of such substances.     

Chemically induced porogen decomposition in premembranes for porogen derived membranes

Studies of chemically induced porogen decomposition in Porogen Derived Membranes show that substantially complete decomposition of porogen molecules, molecularly dispersed in the polymeric matrix, is attainable. Several hours are required for decomposition by reagents penetrating into the premembrane at ambient. Decomposition rate is determined by characteristics of polymer, porogen, and reagent used, by polymer/porogen weight ratio, by reagent concentration, and by temperature. The concept of decomposition by an internal catalyst was also validated. In addition to direct relevance to the new method of membrane formation, the study provides better understanding of phenomena of general interest, such as transport of small molecules through changing polymeric matrices. © 1992 John Wiley & Sons, Inc.     

Gaussian content as a laser beam quality parameter

We propose the Gaussian content (GC) as an optional quality parameter for the characterization of laser beams. It is defined as the overlap integral of a given field with an optimally defined Gaussian. The definition is especially suited for applications where coherence properties are targeted. Mathematical definitions and basic calculation procedures are given along with results for basic beam profiles. The coherent combination of an array of laser beams and the optimal coupling between a diode laser and a single-mode fiber are elaborated as application examples. The measurement of the GC and its conservation upon propagation are experimentally confirmed.     

Guidance of eye movements during conjunctive visual search: The distractor-ratio effect.

The distractor-ratio effect refers to the finding that search performance in a conjunctive visual search task depends on the relative frequency of two types or subsets of distractors when the total number of items in a display is fixed. Previously, Shen, Reingold, and Pomplun (2000) examined participants' patterns of eye movements in a distractor-ratio paradigm and demonstrated that on any given trial saccadic endpoints were biased towards the smaller subset of distractors and participants flexibly switched between different subsets across trials. The current study explored the boundary conditions of this tendency to flexibly search through a smaller subset of distractors by examining the influence of several manipulations known to modulate search efficiency, including stimulus discriminability (Experiment 1), within-dimension versus cross-dimension conjunction search and distractor heterogeneity (Experiment 2). The results indicated that the flexibility of visual guidance and saccadic bias exemplified by the distractor-ratio effect is a robust phenomenon that mediates search efficiency by adapting to changes in the relative informativeness of stimulus dimensions and features. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A perfect zero-knowledge proof system for a problem equivalent to the discrete logarithm

An interactive proof system is calledperfect zero-knowledge if the probability distribution generated by any probabilistic polynomial-time verifier interacting with the prover on input theoremϕ, can be generated by another probabilistic polynomial-time machine which only getsϕ as input (and interacts with nobody!). In this paper we present aperfect zero-knowledge proof system for a decision problem which is computationally equivalent to the Discrete Logarithm Problem. Doing so we provide additional evidence to the belief thatperfect zero-knowledge proof systems exist in a nontrivial manner (i.e., for languages not inBPP). Our results extend to the logarithm problem in any finite Abelian group. This research was partially supported by the Fund for Basic Research Administered by the Israeli Academy of Sciences and Humanities. An early version of this paper appeared inAdvances in Cryptology —Crypto 88 (Proceedings), S. Goldwasser (ed.), pp. 57–70, Lecture Notes in Computer Science, vol. 403, Springer-Verlag, Berlin, 1990.     

Aggressive behavior among Israeli elementary school students and associated emotional/behavioral problems and self-control.

This study aimed to identify aggression patterns among students, compare teachers' and students' reports on aggressiveness, and examine whether emotional and behavioral problems and self-control intercorrelate with aggression and can explain it among students. The study investigated 363 students aged 8 to 11 years and their 12 homeroom teachers in two elementary schools in central Israel. As expected, students reported higher verbal aggression than physical without gender differences in the general tendency. Also, students reported a higher rate of others' aggression toward them than their own aggression toward others. Similarities emerged between students' and teachers' reports. Four types of students were classified: the aggressive initiator (proactive), the aggressive responder (reactive), the passive victim, and a neutral type. An important outcome was the significant negative association of aggressiveness with self-control. Students with higher rates of self-control skills presented lower rates of aggressive behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Time course of phonological activation during reading: Evidence from eye fixations.

Eye fixation data suggest that readers use orthographic codes rather than phonological codes to activate word meanings. Whereas proofreading data show that readers are less likely to detect homophonic errors (e.g., He was in his silk stocking feat) than nonhomophonic errors (e.g., He was in his silk stocking fate), the eye fixations revealed that readers initially experienced as much difficulty encountering a homophonic error as a nonhomophonic one. However, homophony facilitated the recovery process, thus suggesting that phonology has its influence after lexical access. Exp 1 showed that the findings were consistent whether the error was the lower frequency homophone (stocking feat) or the higher frequency homophone (feet of courage). Exp 2 showed that proofreading responses are unreliable indices of error detection because even when readers fail to make an overt error detection response, their eye fixations reveal that they have detected the error. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A community-oriented programme for rehabilitation of persons with arthritis

A community-oriented programme for rehabilitation of persons with arthritis is described. It combines an 8-week ambulatory rehabilitation course (including patient education) at a rehabilitation institution, with long-term self-rehabilitation (at patients' homes), supervised by primary-care nurses. Sixty persons (mean age 54; 80% females) with a 13-year average duration of arthritis, were suffering pain, physical limitations, difficulties in social activities, tension and a tendency to depression. They had completed the course and a 12-month self-rehabilitation at home, and were assessed with the Arthritis Impact Measurement Scales (AIMS) questionnaire on admission to the course, at its completion and 1 year thereafter. Assessment upon completion of the course showed improvement in all areas studied. Measurements at follow-up showed that the majority carried out self-rehabilitation activities and preserved the improved functional status. The programme provided a much-needed service to arthritis sufferers living in the community, and promoted both the reorientation of institution-based rehabilitation professionals towards the community and self-rehabilitation and the cooperation between the institution and primary care.     

On Learning Visual Concepts and DNF Formulae

We consider the problem of learning DNF formulae in the mistake-bound and the PAC models. We develop a new approach, which is called polynomial explainability, that is shown to be useful for learning some new subclasses of DNF (and CNF) formulae that were not known to be learnable before. Unlike previous learnability results for DNF (and CNF) formulae, these subclasses are not limited in the number of terms or in the number of variables per term; yet, they contain the subclasses of k-DNF and k-term-DNF (and the corresponding classes of CNF) as special cases. We apply our DNF results to the problem of learning visual concepts and obtain learning algorithms for several natural subclasses of visual concepts that appear to have no natural boolean counterpart. On the other hand, we show that learning some other natural subclasses of visual concepts is as hard as learning the class of all DNF formulae. We also consider the robustness of these results under various types of noise.An earlier version of this paper appeared in the Proceedings of the Sixth Annual ACM Workshop on Computational Learning Theory, COLT93.Current address: Department of Computer Science, Technion, Israel. e-mail:eyalk@cs.technion.ac.il