Trends in first union formation in post-Soviet Central Asia

This study used recently available survey data to examine trends in the rate of first union formation in the post-Soviet Central Asian republics of Kazakhstan, Kyrgyzstan, Tajikistan and Uzbekistan. For the first time, it shows that the rate of first union formation in each republic is much lower than the Soviet-era level at the end of the 1980s. These results have three implications. First, they complement the literature on Central and Eastern Europe by illustrating the scale of post-socialist demographic change in very different cultural and demographic context. Second, post-Soviet Tajikistan and Uzbekistan here provide interesting examples of countries experiencing dramatic declines in first union formation in a conservative Moslem setting and at the same time as an increase in religiosity and a decrease in female higher education enrolment. Third, more generally, they serve to illustrate profound changes in demographic behaviour during dramatic social and economic change

Development of drive mechanism for an oscillating airfoil

The design and development of an in-draft wind tunnel test section which will be used to study the dynamic stall of airfoils oscillating in pitch is described. The hardware developed comprises a spanned airfoil between schleiren windows, a four bar linkage, flywheels, a drive system and a test section structure

Dictionary matching in a stream

We consider the problem of dictionary matching in a stream. Given a set of strings, known as a dictionary, and a stream of characters arriving one at a time, the task is to report each time some string in our dictionary occurs in the stream. We present a randomised algorithm which takes O(log log(k + m)) time per arriving character and uses O(k log m) words of space, where k is the number of strings in the dictionary and m is the length of the longest string in the dictionary

Pattern Matching in Multiple Streams

We investigate the problem of deterministic pattern matching in multiple streams. In this model, one symbol arrives at a time and is associated with one of s streaming texts. The task at each time step is to report if there is a new match between a fixed pattern of length m and a newly updated stream. As is usual in the streaming context, the goal is to use as little space as possible while still reporting matches quickly. We give almost matching upper and lower space bounds for three distinct pattern matching problems. For exact matching we show that the problem can be solved in constant time per arriving symbol and O(m+s) words of space. For the k-mismatch and k-difference problems we give O(k) time solutions that require O(m+ks) words of space. In all three cases we also give space lower bounds which show our methods are optimal up to a single logarithmic factor. Finally we set out a number of open problems related to this new model for pattern matching.Comment: 13 pages, 1 figur

Differential Shoot Feeding by Adult \u3ci\u3eTomicus Piniperda\u3c/i\u3e (Coleoptera: Scolytidae) in Mixed Stands of Native and Introduced Pines in Indiana.

The larger pine shoot beetle Tomicus piniperda, a native bark beetle of Europe and Asia, was found in North American Christmas tree plantations in 1992 in Ohio. Subsequent surveys found it in six U.S. states and in one Canadian province. The first natural area where Tomicus was found to be established was at the Indiana Dunes State Park, in northwestern Indiana near the Lake Michigan shoreline. Pine stands were surveyed for fallen shoots to determine the extent and range of shoot feeding in the park. Within the study area adult Tomicus fed on the shoots of all native pines (Pinus banksiana, P. resinosa. and P. strobus.), as well as the European species (P. sylvestris). More fallen shoots were collected from both P. resinosa and P. sylvestris than expected from their basal areas in the sampled stands. This contrasted with P. banksiana and P. strobus whose shoots were underrepresented relative to their basal areas. The relatively high numbers of fallen shoots found for P. resinosa suggests that red pines in the Great Lakes region will easily support populations of T. piniperda

Post-Newtonian constraints on f(R) cosmologies in metric formalism

We compute the complete post-Newtonian limit of the metric form of f(R) gravities using a scalar-tensor representation. By comparing the predictions of these theories with laboratory and solar system experiments, we find a set of inequalities that any lagrangian f(R) must satisfy. The constraints imposed by those inequalities allow us to find explicit bounds to the possible nonlinear terms of the lagrangian. We conclude that the lagrangian f(R) must be almost linear in R and that corrections that grow at low curvatures are incompatible with observations. This result shows that modifications of gravity at very low cosmic densities cannot be responsible for the observed cosmic speed-up.Comment: 10 pages, no figures, revtex

ECOLABELS AND ECONOMIC EFFICIENCY: SOME PRELIMINARY RESULTS

The public provision of information about the environmental performance of firms and products has generated considerable enthusiasm and become a common instrument of environmental regulation, even though the economic analysis of the social welfare properties of these policies is quite limited. This paper proposes a model for examining these properties.Research Methods/ Statistical Methods,

Regenerable biocide delivery unit

A method and apparatus are disclosed for maintaining continuous, long-term microbial control in the water supply for potable, hygiene, and experimental water for space activities, as well as treatment of water supplies on Earth. The water purification is accomplished by introduction of molecular iodine into the water supply to impart a desired iodine residual. The water is passed through an iodinated anion exchange resin bed. The iodine is bound as I-(sub n) at the anion exchange sites and releases I(sub 2) into the water stream flowing through the bed. The concentration of I(sub 2) in the flowing water gradually decreases and, in the prior art, the ion-exchange bed has had to be replaced. In a preferred embodiment, a bed of iodine crystals is provided with connections for flowing water therethrough to produce a concentrated (substantially saturated) aqueous iodine solution which is passed through the iodinated resin bed to recharge the bed with bound iodine. The bed of iodine crystals is connected in parallel with the iodinated resin bed and is activated periodically (e.g., by timer, by measured flow of water, or by iodine residual level) to recharge the bed. Novelty resides in the capability of inexpensively and repeatedly regenerating the ion-exchange bed in situ