Localisation of light in disordered lattices

A short review of the basic concepts underlying localisation of light through multiple scattering in disordered media is provided, in conjunction with the ideas related to the universal features occurring during transport of waves and Anderson localisation. Progress in the area is described, including the recent experimental observation of localisation in photonic lattices upon which random perturbations are superimposed, which has constituted the first observation of Anderson localisation in any perturbed periodic system. Subsequently, some of the new intriguing concepts in the field of localisation of light are discussed, among them the combination of nonlinearity and disorder, and their effects on waves transport. Finally, being somewhat speculative, future directions in the area and their potential impact on the basic understanding of the universal phenomena associated with transport of waves are suggested.     

Designing efficiencies: The parallel narratives of distance education and composition studies

Distance education (DE) programs at many universities have been initiated to generate new efficiencies for the academic process, particularly cost efficiency and pedagogical efficiency. In writing studies, this move toward digitally mediated instruction has, in some classrooms, recreated practices that resonate with the pedagogy that resulted from Current-Traditional Rhetoric (CTR). Thus, a trace of distance education's and composition studies’ parallel narratives demonstrates that writing studies has already addressed some of the questions (and concerns) that online writing instruction raises. By specifically focusing on the tensions created by negotiating cost efficiencies and pedagogical efficiencies with communication efficiencies and medium efficiencies, we interrogate current administrative decisions as well their pedagogical outcomes. We conclude by proposing strategies for rearticulating future narratives about online writing instruction in potentially productive ways.     

A Comparison of Four Monte Carlo Methods for Estimating the Probability of s-t Connectedness

This paper describes and compares the performance of four alternative Monte Carlo sampling plans for estimating the probability that two nodes, s and t, are connected in an undirected network whose arcs fail randomly and independently. Models of this type are commonly used when computing the reliability of a system of randomly failing components. The first method, dagger sampling, relies for its advantage on inducing negative correlation between the outcomes of the replications in the sample. The second method, sequential destruction/construction exploits permutation properties of arc failures and successes. The third method uses easily determined bounds on the reliability probability to gain an advantage. The fourth approach enumerates all failure sets of the network to achieve its appeal. An example based on a 30-arc 20-node network illustrates the variance reducing features and the time and space needs of each sampling plan. Dagger sampling and sequential construction offer limited benefits when compared to the bounds and failure-sets methods. The failure-sets method performs best on the example for small failure probabilities. However, in general it offers no guarantee of a smaller variance than crude Monte Carlo and requires substantially more memory than the other methods. Moreover, this memory requirement can grow rapidly as the size of the network increases. By contrast, the bounds method guarantees a smaller variance than for crude Monte Carlo sampling and has modest memory requirements.     

Emergency laboratory diagnosis of diphtheria

The immune response to diphtheria toxin (clinically pronounced infection or carrier state with the presence of toxigenic bacteria) or toxoid (vaccination) the blood has been found to contain lymphocytes (1.00-5.71%), specifically binding diphtheria toxoid (DTX). The method for the determination of lymphocytes, specifically binding DTX, may serve both for early diagnosis and in the process of the disease, irrespective of the injection of therapeutic serum to the patient. The result of the test is obtained 2-3 days earlier than the positive result of the bacteriological analysis. The set of immune reagents for the rapid diagnosis of diphtheria by the method of rosette formation has been developed.     

Design and performance of externally modulated 1.5-μm lasertransmitter in the presence of chromatic dispersion

Key laser and modulator characteristics that impact the use of externally modulated lasers in the presence of chromatic dispersion, excluding effects due to fiber nonlinearities, are reviewed. After a brief consideration of transmission performance with directly modulated 1.5-μm DFB lasers which have limited application of up to 80 km at 2.5 Gb/s, the key design characteristics of externally modulated transmitters are discussed. Experimental results showing the effects of modulator chirp and laser linewidth at a 2.5-Gb/s transmission rate are presented. It is found that lasers with CW linewidth under 100 MHz have less than 2-dB dispersion penalty for 600 km of non-dispersion-shifted fiber. Lower dispersion penalties can be realized if the modulator chirp is tuned so as to narrow the transmitted pulses. Excellent modulator stability is demonstrated for 60 days of error- and degradation-free 2.5-Gb/s operation     

The effect of patient and clinician ideology on clinical judgment: A study of ideological countertransference.

Examined the influence of patient and clinician values on clinical judgment, using 363 clinical psychologists. Ss each rated 2 case histories. One case had been altered to reflect 1 of 4 conditions (right-wing [RW] religious, RW political, left-wing [LW] religious, or LW political), and the other case reflected no ideological commitment. Cases with "extreme" ideologies were rated more negatively on 4 clinical judgment decisions. Unexpectedly, ideological cases were almost 3 times more likely to be diagnosed obsessive-compulsive and were less likely to be diagnosed with generalized anxiety disorder than nonideological cases. Clinicians need to be sensitive to issues of "ideological countertransference." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sampling from the poisson distribution on a computer

This paper describes a method of sampling from the Poisson distribution on a computer that appears to be less costly than a recently suggested method in [1]. The proposed method relies on a conventional search using the inverse transform approach for nonintegral μ<7, on a modification of the inverse transform approach that begins the search at the mode for integral μ, and on a combination of these two approaches for nonintegral μ>7. For large μ the sampling cost is proportional to μ^1/2. The paper also shows that for μ≥15 an incidental error occurs by using max (0, [μ+Yμ^1/2+0.5]) whereY is fromN(0,1). Since the sampling cost ofY is a constant, this approach places an upper bound on the cost of generating a Poisson variate.