Intellectual deficits after transient tyrosinemia in the term neonate

An analysis was made of the obstetric history of 1,360 patients who were delivered in 1971. It involved 3,185 pregnancies. The aim of the study was to evaluate the risk of spontaneous termination of the pregnancy, worked out from its demographic aspect. Several ideas are worthy of consideration. The risk of spontaneous intra-uterine death is cumulative, sharply increased by a repetition of such cessation of pregnancy. The same patients often undergo intentional abortion repeatedly. The respective risks of spontaneous and provoked interruption of pregnancy have been studied in greater detail as a function of parity.     

The influence of nonmetallic inclusions on the mechanical properties of steel: A review

The literature regarding the influence of nonmetallic inclusions on the mechanical properties of steel is reviewed, with critical comments on various studies. A brief discussion of inclusion rating methods and a synopsis of the effects of applied stress on inclusions in an isotropic, elastic matrix are presented. The parameters considered are tensile strength, impact strength, reduction of area, fatigue properties and fracture toughness. It is concluded that in many applications, the type of inclusions are more important than the total content and as matrix strength increases, the notch effect of inclusions becomes more significant. Also, mechanical properties can be influenced by any one or a combination of the following inclusion parameters; shape, size, quantity, interspacing, distribution, orientation, interfacial strength, and physical properties relative to the matrix.     

Mixed-radix MVL Function Spectral and Decision Diagram Representation

Discrete finite-valued functions are increasingly important in applications involving automation and control. In particular, it is evident that industry is focusing on Systems-on-a-Chip (SoC) where the integration of analog (infinite-valued) and digital (binary-valued) circuits must co-exist. As designers struggle with these interfacing issues, it is natural to consider the intermediate circuits that can be modeled as multi-valued, discrete logic-level circuits. This viewpoint is not unprecedented as such principles have been used for at least the past twenty years in telecommunications protocols. If an analogous approach is considered in control systems implemented in Integrated Circuit (IC) designs, it is proposed that spectral analysis may provide an important role and efficient methods for computing such mixed-radix function spectra are described here. These methods are formulated as transformations of word-level decision diagrams representing the underlying arithmetic expressions and can be implemented as graph traversal algorithms. The theoretical foundation of the spectral transform of a mixed-radix function is presented and the equivalence of the resulting spectrum and the spectrum of a Cayley graph is shown.     

A linearised pixel-swapping method for mapping rural linear land cover features from fine spatial resolution remotely sensed imagery

Accurate maps of rural linear land cover features, such as paths and hedgerows, would be useful to ecologists, conservation managers and land planning agencies. Such information might be used in a variety of applications (e.g., ecological, conservation and land management applications). Based on the phenomenon of spatial dependence, sub-pixel mapping techniques can be used to increase the spatial resolution of land cover maps produced from satellite sensor imagery and map such features with increased accuracy. Aerial photography with a spatial resolution of 0.25 m was acquired of the Christchurch area of Dorset, UK. The imagery was hard classified using a simple Mahalanobis distance classifier and the classification degraded to simulate land cover proportion images with spatial resolutions of 2.5 and 5 m. A simple pixel-swapping algorithm was then applied to each of the proportion images. Sub-pixels within pixels were swapped iteratively until the spatial correlation between neighbouring sub-pixels for the entire image was maximised. Visual inspection of the super-resolved output showed that prediction of the position and dimensions of hedgerows was comparable with the original imagery. The maps displayed an accuracy of 87%. To enhance the prediction of linear features within the super-resolved output, an anisotropic modelling component was added. The direction of the largest sums of proportions was calculated within a moving window at the pixel level. The orthogonal sum of proportions was used in estimating the anisotropy ratio. The direction and anisotropy ratio were then used to modify the pixel-swapping algorithm so as to increase the likelihood of creating linear features in the output map. The new linear pixel-swapping method led to an increase in the accuracy of mapping fine linear features of approximately 5% compared with the conventional pixel-swapping method.     

Frequency selective lens antenna

A variant of the hemispherical microwave lens antenna is reported where the ground plane region is modified through use of a frequency selective surface. This allows discrimination of frequencies by two closely spaced primary feeds. A scale model is reported operating at 12 and 30 GHz     

Assessment of conformational parameters as predictors of limited proteolytic sites in native protein structures

Despite the importance of limited proteolysis in biological systems it is often difficult to rationalize why a proteinase hydrolyses a particular bond, given a simple sequence specificity alone. Understanding of the structural properties limiting the proteolysis represents a first step on the pathway to control and manipulation of this phenomena. An expanded set of nick-sites in proteins of known tertiary structure, cut by both narrow and broad specificity proteinases, has been generated yielding a robust data set of strictly limited sites. A critical evaluation of an expanded set of conformational parameters revealed a strong correlation with limited proteolytic sites, although they are only modest predictors in isolation. The overall predictive power is significantly improved when the conformational parameters are combined in a weighted predictive scheme that permits their relative importance to be compared via a Metropolis search protocol. A subset of the parameters performs equally well demonstrating the key determinants of susceptibility. The derived predictive algorithm has been made available via the internet. Its utility for predicting other surface-correlated features is also discussed.      

A note on the effect of initial particle spin on the rebound behaviour of oblique particle impacts

When particle systems are in the collisional regime normal impacts are rare events. Oblique impacts are the norm and are much more complex due to the tangential elastic interaction. The collisional behaviour and subsequent rebound kinematics due to impact are further complicated by particle rotations prior to the impact event. Almost all previous published work on particle impact have ignored the effect of initial particle spin. In this paper we demonstrate that all the aspects of the rebound kinematics can be normalised by considering an effective impact angle that is defined by the ratio of the relative initial tangential to normal surface velocities of the two impacting bodies.     

Addition-based exponentiation modulo 2/sup k/

A novel method for performing exponentiation modulo 2/sup k/ is described. The algorithm has a critical path consisting of k dependent shift-and-add modulo 2/sup k/ operations. Although 3 is the preferred exponent base, the algorithm can be extended easily in order to perform the general binary powering operation.     

Farm location and farmers’ performance on the Hamza minor canal

A sample of 36 tenant farmers, at varying locations along the Hamza Minor Canal of the Sudan Gezira Scheme, were surveyed in 1986/7, the purpose being to estimate locational variation in irrigation water supplies and. tenancy income levels. Results show that for the main crop, cotton, there are declines in water balance, crop yields and net returns between head, middle and tail end of the canal. However, in middle and tail‐end locations groundnuts yield a substantially higher net return per hectare than the main crops, cotton and wheat, which suggests that changes in crop rotations would be profitable.