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The pediatrician makes a judgment of the degree of illness (toxicity) of a febrile child based on observation prior to history and physical examination. In order to define valid and reliable observation data for that judgment, data from two previous studies were used to construct three-point scales of 14 observation items correlated with serious illness in those reports. Between Nov 1, 1980 and March 1, 1981, these 14 scaled items were scored simultaneously by attending physicians, residents, and nurses prior to history and physical examination on 312 febrile children aged ≤24 months seen consecutively in our Primary Care Center-Emergency Room and in one private practice. Of these 312 children, 37 had serious illness. Multiple regression analysis based on patients seen by at least one attending physician in the Primary Care Center revealed six items (quality of cry, reaction to parents, state variation, color, state of hydration, and response to social overtures) that were significant and independent predictors of serious illness (multiple R = 0.63). The observed agreement for scoring these six items between two attending physicians who saw one third of the patients ranged from 88% to 97%. The chance corrected agreement levels (κw) for these six items were, with one exception, clinically significant (κw = .47 to .73). A discriminant function analysis revealed that these six items when used together had a specificity of 88% and a sensitivity of 77% for serious illness. Individual scores for each of the six key items were added to yield a total score for each patient. Only 2.7% of patients with a score ≤10 had a serious illness; 92.3% with a score ≥l6 had a serious illness. The sensitivity of the six-item model for serious illness when combined with history and physical examination was 92%. In the population studied, this predictive model, when used prior to history and physical examination, was reliable, predictive, specific, and sensitive for serious illness in febnile children. It was most sensitive when combined with history and physical examination. The model wifi need to be validated on a new population of patients.

Various aspects of the secondary ion and electron emission from surfaces of solids bombarded by MeV ions are briefly presented. Two examples of applications in very different fields are given: the charge state variation of a fast ion traversing a solid and the desorption of very large molecules which can be desorbed intact from organic solid films.

The analysis is made of modern methods and equipment for testing materials at cryogenic temperatures. The authors describe an automated complex developed at the Institute for Problems of Strength of the Academy of Sciences of the Ukr. SSR for low-temperature tests of structural materials under conditions of controlled biaxial loading which imitates the operation of cryogenic vessels and pipe-lines. Analyzed are the results of experimental investigations into the laws of elasto-plastic deformation which were carried out on the materials of different grades loaded in accordance with complex programs over a wide temperature range. Main attention is given to new effects which are associated with the influence of cooling on the process of deformation under conditions of stress state variation. Variants are presented of analytical description within the framework of the elasto-plastic deformation theory of the experimentally established laws.

A n analysis is presented of the propagation of stress waves from a unit step impact pulse concentrated obliquely at a point on the upper surface of an infinite elastic plate whose thickness is of the order of magnitude of a wave length. An expansion method of Cagniard is employed to separate successively reflected waves of increasing time delay. The problem of performing a Laplace transform and its inversion is solved by use of Cagniard's artifice. Stress expressions and sets of numerical principal stress values are obtained for the stress state at points along the z -axis, for oblique angles of incidence of 30° and 60°. Stress surfaces are drawn to depict the principal stress state variation with time and the jump discontinuity wave fronts signalling respective wave arrivals.

Due to the lack of information of subsurface lunar regolith stratification which varies along depth, the drilling device may encounter lunar soil and lunar rock randomly in the drilling process. To meet the load safety requirements of unmanned sampling mission under limited orbital resources, the control strategy of autonomous drilling should adapt to the indeterminable lunar environments. Based on the analysis of two types of typical drilling media (i.e., lunar soil and lunar rock), this paper proposes a multi-state control strategy for autonomous lunar drilling. To represent the working circumstances in the lunar subsurface and reduce the complexity of the control algorithm, lunar drilling process was categorized into three drilling states: the interface detection, initiation of drilling parameters for recognition and drilling medium recognition. Support vector machine (SVM) and continuous wavelet transform were employed for the online recognition of drilling media and interface, respectively. Finite state machine was utilized to control the transition among different drilling states. To verify the effectiveness of the multi-state control strategy, drilling experiments were implemented with multi-layered drilling media constructed by lunar soil simulant and lunar rock simulant. The results reveal that the multi-state control method is capable of detecting drilling state variation and adjusting drilling parameters timely under vibration interferences. The multi-state control method provides a feasible reference for the control of extraterrestrial autonomous drilling.

Multiple refractive state measurements were made on a male and female hooded seal (Cystophora cristata) when the eyes were exposed to air and to water. The measures, made by conventional retinoscopy and by photorefraction, show that the seals are moderately hyperopic (2-3 diopters) in water and moderately myopic (2-4 diopters) in air. No significant astigmatism was noted in either medium. The absence of refractive state variation over time suggests that an accommodative mechanism is insignificant or absent, although histological study indicates that the ciliary muscle is well developed. Photokeratoscopy, carried out on two animals with two keratoscopic instruments, show that the cornea is relatively flat (30 mm, or about one-half the diameter of the eye). Furthermore the cornea is only slightly astigmatic (less than 1 diopter). The refractive power of the external corneal surface (in air), calculated from a measurement of corneal refractive index of 1.378, amounts to only 10 or 11 diopters. As in the typical fish eye, hooded seal lenses are spherical or nearly spherical in shape (24-23 mm), and have short focal lengths (30-32 mm). Focal measures for rays at varying distances from the lens center indicate that spherical aberration is well corrected. There is no indication in this seal species, of a previously reported adaptation involving a highly astigmatic cornea which together with a slit pupil can minimize the optical effect of movement from water to air.

I address the degree to which variation in exposure to e-commerce is associated with entry and exit in the retail industry at the county level. To measure exposure to e-commmerce, I rely on within-state variation in relative search frequency for the phrase “amazon prime” as reported by Google Trends. To generate exogenous variation in this e-commerce exposure measure, I use within state variation in the relative search frequency for “porn” and “cat videos”. FEIV estimates suggest at least 10 of the 27 retail industry groups experience net exit with increasing e-commerce exposure, while at least 6 experience net entry. Future work investigating the mechanisms generating this heterogeneity will be fruitful.

Data for reaction of CH3I and CD3I with substituted pyridines were previously argued to indicate a variant transition state as rate of reaction was varied, but the fact that both sets of results follow LFER's may be taken as evidence against such a conclusion.