Attitudes of Israeli Muslims at risk of genetic disorders towards pregnancy termination

OBJECTIVES: (1) To examine attitudes towards termination of pregnancy (TOP) among high-risk and non-high-risk (for cystic fibrosis) Arab-Muslims, and (2) to examine the effect of an intervention, which among other things related explicitly to TOP. METHODS: The study comprised three groups: (1) an intervention group at high risk for CF, which received community genetic counseling; (2) a control group at high risk for CF, and (3) a control group from the general population. The latter two groups were exposed to minimal intervention. Attitudes were measured two or three times during a 1-year period (for the control and intervention groups, respectively). RESULTS: Predictors of an affected fetus being considered a legitimate cause for TOP were religiosity, familiarity with an affected child, and benefits of the test. Predictors of individuals (hypothetically) choosing abortion in the case of an affected fetus were education and age. No change occurred in the attitudes of participants (either experimental or control groups) in the course of 1 year. CONCLUSIONS: Other possible intervention options are discussed, and specifically, the advantages of using opinion leaders such as clergy and medical staff.     

Bounds for algebraic gossip on graphs

We study the stopping times of gossip algorithms for network coding. We analyze algebraic gossip (i.e., random linear coding) and consider three gossip algorithms for information spreading: Pull, Push, and Exchange. The stopping time of algebraic gossip is known to be linear for the complete graph, but the question of determining a tight upper bound or lower bounds for general graphs is still open. We take a major step in solving this question, and prove that algebraic gossip on any graph of size n is O(Δn) where Δ is the maximum degree of the graph. This leads to a tight bound of for bounded degree graphs and an upper bound of O(n²) for general graphs. We show that the latter bound is tight by providing an example of a graph with a stopping time of . Our proofs use a novel method that relies on Jackson's queuing theorem to analyze the stopping time of network coding; this technique is likely to become useful for future research. © 2012 Wiley Periodicals, Inc. Random Struct. Alg., 45, 185–217, 2014     

Surface-enhanced Raman scattering detection of cholinesterase inhibitors

A new sensitive surface-enhanced Raman scattering (SERS) assay for detection of cholinesterase inhibitors such as organophosphorous pesticides using silver colloidal nanoparticles was developed and optimized. Acetylcholinesterase (AChE) mediated the hydrolysis of acetylthiocholine to produce thiocholine, which interacted with the silver nanoparticles to give a specific SERS spectrum. Variation in enzyme activity due to inhibition was measured from changes in intensity of a characteristic peak (772 cm⁻¹) of the SERS spectrum that was directly correlated with the concentration of produced thiocholine. The method was demonstrated for the detection of paraoxon as reference AChE inhibitor. Limit of detection of paraoxon for 5 min incubation at 25 °C was 1.8 × 10⁻⁸ M. This assay can be utilized for the detection of trace amounts of any AChE inhibitor.     

Algebraic signatures of convex and non-convex codes

A convex code is a binary code generated by the pattern of intersections of a collection of open convex sets in some Euclidean space. Convex codes are relevant to neuroscience as they arise from the activity of neurons that have convex receptive fields. In this paper, we develop algebraic methods to determine if a code is convex. Specifically, we use the neural ideal of a code, which is a generalization of the Stanley–Reisner ideal. Using the neural ideal together with its standard generating set, the canonical form, we provide algebraic signatures of certain families of codes that are non-convex. We connect these signatures to the precise conditions on the arrangement of sets that prevent the codes from being convex. Finally, we also provide algebraic signatures for some families of codes that are convex, including the class of intersection-complete codes. These results allow us to detect convexity and non-convexity in a variety of situations, and point to some interesting open questions.     

The kBr/kCl element effect for nucleophilic vinylic substitution of the highly reactive tricyanovinyl-x system by substituted anilines

The element effects for the substitution of tricyanovinyl chloride and bromide by the $\text{p}$-position of three dialkylanilines are k_Br/k_Cl=2.37±0.18. An early transition state for the expulsion of the halide ion from the intermediate zwitterion is indicated.     

Reactions of enols of amides with diazomethane

The reaction of 10 carboxamides activated by two beta-electron-withdrawing groups, which mostly exist completely or partially in their enol forms, with diazomethane was investigated. The main outcome is the diversity of reactions observed. With the most acidic enols 3-7, activated by at least one trifluoroethoxycarbonyl group or a cyano group, O-methylation or O,N-dimethylation takes place. With beta-dimethoxycarbonyl-activated systems 5 and 8, the C-methylation product of the amide form was one of the products. With a Meldrum's acid anilide enol 2, a cleavage took place leading to the C-alkylated imine having a CH(CO(2)Me)(2) group. Exchange of one 2,2,2-trifluoroethoxycarbonyl by a methoxycarbonyl in the C,N-dimethylation product of Me(2)CHNHC(OH)[double bond]C(CO(2)CH(2)CF(3))(2) 4 took place. The 2-anilido-1,3-cyclopentanedione 10 was methylated on a ring carbonyl while the enol of the 1,3-indanedione analogue 11 reacted with three diazomethane molecules and underwent a ring expansion and O-methylation to the 3-anilido-1,4-dimethoxynaphthalene. It is suggested that the reaction initiates by protonation of the diazomethane by the enol and an approximate qualitative relationship exists between the acidity of the enol and K(enol) and the regioselectivity of the reaction.     

Subcellular Localization of Sulfonated Tetraphenyl Porphines in Colon Carcinoma Cells by Spectrally Resolved Imaging

Subcellular localization of the dye, 5,10,15,20-tetra(4-sul-fonatophenyl)porphine (TPPS₄) and the more hydrophobic dye, 5,10,15,20-tetra(1-sulfonatophenyl)porphine (TPPS₁), in murine colon carcinoma cells was studied by spectrally resolved imaging (SRI) combined with image processing techniques. Spectrally resolved imaging enabled the acquisition of multipixel fluorescence spectra (>10⁴) from a single cell. Demarcation of specific localization sites and segregation of the irrelevant fluorescence were based on the pixel spectra and by operating the functions of spectral similarity mapping (SSM), principal component analysis (PCA) and spectral classification. The SRI revealed the fine details of the photochemical process that clarify some aspects of subcellular damage. The SRI depicted the differences between TPPS₄ and TPPS, with respect to their initial localization and their fate at the end of the photochemical effect. The dye TPPS₄ was localized initially in lysosomal vesicles, and upon irradiation fluorescence was seen in the nucleus as well as in vesicles. Some of the vesicles were closely related to the nucleus, as resolved by SSM, PCA and spectral classification. Additional light exposure stimulated relocalization of TPPS₄ into the nucleus as well as into the nucleolus, which was clearly depicted by SSM and PCA. Spectral classification showed a third, weak residual cytoplasmic array around the nucleus. The dye TPPS, concentrated in a Golgi-like complex and was resolved in the nuclear envelope and in small vesicles: it was not redistributed into other compartments upon photosensitization. Serum supplementation to the incubation media of colon carcinoma cells treated with TPPS₄ or TPPS, did not change the localization patterns. Pixel spectra of the two dyes in the cells showed spectral shifts and expanded shoulders due to microenvironmental effects. Thus, the chemical nature of the sulfonated phenyl porphines, and not their interaction with serum proteins, was the main determinant of their binding to the lysosomes, nucleus, nucleolus, nuclear envelope or Golgi.     

The maximum amplitude cost functional in linear systems

The maximum amplitude cost of a control function u(t) taken to be ess sup g(t, u(t)), where g(t, u) is a given function. (A particular example is g(t, u) = the norm of u.) We consider linear systems with this cost functional. The existence of optimal control is proved, and it is shown that the ess sup is uniformly essential with respect to the optimal controls. Properties of the extended attainable set are discussed and compared with the case of an integral cost. Finally, we show in what sense a cost functional of the form $\text{(∝ g(t, u(t))}{}^{\mathrm{q}}\text{)}{}^{\mathrm{<mtext>1</mtext><mtext>q</mtext>}}$ approximates the ess sup cost functional.     

A New Heuristic for the Quadratic Assignment Problem

We propose a new heuristic for the solution of the quadratic assignment problem. The heuristic combines ideas from tabu search and genetic algorithms. Run times are very short compared with other heuristic procedures. The heuristic performed very well on a set of test problems.     

An EOQ Model with Substitutions Between Products

In this paper, we present an economic order quantity (EOQ) model when two products are required, and one can be substituted for the other, if necessary, at a given unit cost. We consider three cases: (i) when there is no substitution between the products, (ii) when there is full substitution between the products, and (iii) when there is partial substitution between the products. In a deterministic setting with proportional substitution costs, we would expect to find full substitution or no substitution being optimal, depending on the cost parameters. However, we observe that full substitution is never optimal; only partial substitution or no substitution may be optimal. This result can best be explained due to the non-linearity of the decision variables in the total cost expression. Finally, we present an algorithm to compute the optimal order quantities.