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The toxicity of catechol, hydroquinone and resorcinol requires their determination at low concentration levels over a wide linear range. Therefore, in this work we present a new bio-sensing device fabricated by a Soft Plasma Polymerization (SPP) technique for the determination of dihydroxybenzene isomers in real water samples. The Corona SPP technique was applied to the deposition of a bio-recognition layer based on the laccase enzyme. In comparison to conventional methods of biosensor construction, application of the SPP technique allows reduction of its preparation time from several hours to ∼2 min with no chemical consumption. The fabricated biosensor was characterized to find the optimum experimental conditions and determine its response time, sensitivity, linear range and selectivity coefficient. The optimum environment of the bio-sensor for generation of catechol, hydroquinone and resorcinol oxidation peaks was found to be acetate buffer at pH = 6.13. The biosensor exhibited a wide linear response both to catechol, hydroquinone and resorcinol with good sensitivity and high regression coefficient. Further studies showed also that the fabricated biosensor can be successfully applied to simultaneous determination of hydroquinone and resorcinol as well as catechol and resorcinol.

Lampropholis guichenoti is an oviparous lizard that lays eggs with a calcareous outer shell. We used immunofluorescence microscopy to describe the occurrence and distribution of Ca2+ ATPase pumps in the uterus of L. guichenoti at different stages of the reproductive and egg-shelling cycles. Ca2+ ATPase pumps were not demonstrated by immunofluorescent techniques in any uterine tissue until egg-shelling had commenced and at least partly calcified eggs were in the uterus. During egg-shelling, Ca2+ ATPase pumps occur on the apical and baso-lateral surfaces of uterine epithelial cells, and those of associated shell glands in the stroma of the uterus. We conclude that Ca2+ ATPase pumps provide a major mechanism for deposition of the calcareous eggshell of L. guichenoti and that the pumps are up-regulated when required in the reproductive cycle. Furthermore, it is likely that specific calcium glands in the stroma of the uterus are involved in the rapid transport required for egg-shelling, but the differential contribution of luminal and glandular epithelial cells is not known.

This study investigated adolescents' and parents' perceptions regarding smoking behavior, attitudes toward smoking, and smoking communication. Instruments were developed to measure multidimensional smoking communication messages and smoking attitudes in 140 mother–adolescent dyads. The prediction of relevant adolescent smoking variables is multifaceted and complex. Results indicated that adolescents' smoking behavior was related to adolescents' smoking attitudes and adolescents' perceptions of mothers' smoking related inquiries. Adolescents' smoking attitudes were related to mothers' smoking attitudes and adolescents' perceptions of mothers' smoking related inquiries and consistent and credible anti-smoking messages. Adolescents' perceptions of mothers' anti-smoking messages were related to mothers' smoking behavior. Adolescents' perceptions of mothers' smoking rules and mothers' reports of anti-smoking involvement and smoking rules were related to mothers' smoking behavior and attitudes. Mothers' reports of pro-smoking messages were related to their smoking attitudes. The present research suggests that the adolescent–mother smoking communication process is an important area to further explore in understanding adolescents' smoking behavior.

Frequent evolution of viviparity in squamate reptiles provides excellent models for study of the transition from oviparity to viviparity, and the evolution of complex placentae. Embryonic reptiles have a chorioallantoic placenta at the embryonic pole of the egg, and an omphaloplacenta at the abembryonic pole. The uterus of viviparous reptiles and mammals exhibits common plasma membrane transformation including uterodome formation associated with pregnancy. The transition from oviparity to viviparity requires few changes: (1) reduction in an eggshell, (2) delay of expulsion of oviposition/birth, (3) increased vascularisation of the uterus for gas exchange. We used immunohistochemistry to address the question of eggshell thinning in a range of species, and SEM and TEM to infer the functions of different placental regions in one species with a complex placenta. We conclude that: (1) changes in the calcium channels among species accompany the evolution of viviparity; (2) the omphaloplacenta has a role in nutrient transport via apocrine secretion and histotrophy; (3) the placentome has a role in nutrient transport, but not via apocrine secretion; (4) the paraplacentome of the chorioallantoic placenta has a major role in gas exchange.

Experiments comparing the nutritive value of cereal straws from different genotypes are often complicated by the difference in plant height which is affected by genotype and the amount of rainfall. Two experiments were therefore conducted to study the morphological characteristics, chemical composition and rumen degradation of barley straw fractions from several genotypes over a range of watering levels. The range was obtained by using sprinklers to apply various levels of water in addition to normal rainfall. In Experiment 1, there were four genotypes of barley and three levels of watering, and in Experiment 2, another three genotypes of barley and four levels of watering. Grain and straw yield, stem height, the proportions of chaff, leaf and stem, the chemical composition of these morphological fractions, and the dry matter losses (DML) of fractions from nylon bags placed in the rumen, were determined. The extent and rate of DML was estimated. In both experiments, applying additional water almost doubled stem height. The effects of watering level on grain and straw yield and plant morphological fractions were therefore generally greater than the effects of genotype. In Experiment 1, genotype and watering level had few significant effects on the chemical composition of straw fractions and in Experiment 2 chaff composition was generally affected by genotype, but both genotype and watering level usually affected leaf composition. Both genotype and watering level affected the extent of digestion of leaf in Experiment 1, whereas in Experiment 2 genotype was more important than watering level in affecting the extent and rate of digestion of stem. The results show that water stress can affect the composition and rumen degradation of barley straw to a similar extent as can genotype. This finding should be recognised when comparing cereal straw from genotypes harvested in different years and locations in semi-arid environments.

Processing of agglomerated particulate products can lead to attrition by abrasive wear as the agglomerates move relative to one another. In order to investigate this damage mechanism under controlled conditions, bar-shaped silica sand agglomerates of a range of strengths have been formed by addition of appropriate proportions of polyvinylpyrrolidone binder (molecular weight 44 000). These were then tested for wear resistance against various grades of abrasive paper and by rubbing against each other. In common with many materials, it was found that the wear rate is proportional to total sliding distance and to normal load, and independent of relative velocity. A simple Coulombic interlocking wear model is advanced to account for the dependence of wear rate on the size of abrasive particle forming the countersurface. In sustained (multi-pass) sliding, the presence of the debris reduces the attrition rate significantly. This phenomenon has been exploited by various workers who introduced solid lubricants into particle-processing devices in order to reduce attrition. The wear rate of agglomerates of different strengths has been found to be approximately proportional to the reciprocal of K c , the critical stress intensity factor measured for the same bar agglomerates using the three-point bend test. This relationship between attrition rate and K c has also been found for attrition in fluidized beds.

Casuarina equisetifolia, Albizia procera, Eucalyptus robusta and two varieties of Leucaena leucocephala (K8 and P.R.) were grown for 5.5 years in an experimental plantation in the Lajas Valley of Puerto Rico (18°N, 67°W). Rates of biomass accumulation were high, resulting in correspondingly high rates of nutrient accumulation in harvestable biomass. A comparison among species and among tissue types within species indicated that nutrient-use efficiency for N, P, K, Ca and Mg varied widely among species (ranging up to 10-fold differences) and tissues (up to 15-fold). With the highest growth rate, Casuarina was most efficient in using nutrients (N, P, K and Mg) to build biomass. With a quarter of Casuarina's growth rate, Leucaena K8 was the least efficient (N, K, Ca and Mg). For most of the studied nutrients, stem wood and large branches were the most nutrient-efficient tissue, followed by small branches, bark and then leaves. Nutrients stored in the litter layer below these species varied up to three-fold among species. Using a variety of species and biomass harvest scenarios, this study demonstrated the potential for significant alterations in the high rates of nutrient removal associated with short-rotation, intensively managed plantations.

Process-induced damage in epitaxial InP films following CH 4 /H 2 reactive ion etching has been studied using a noncontact photothermal radiometric (PTR) probe. A significant shift in measured PTR amplitude as a function of applied bias voltage has been observed. Results are correlated with both Raman and photoluminescence measurements.

The appearance of a central hole through optical lithographically defined photoresist discs is identified as a Fresnel diffraction phenomenon known as Poisson's Spot. The diffraction is found to be strongly dependant upon mask-photoresist separation and, thus, could constitute a useful technique for optimising this aspect of routine optical lithography.

Trees of Casuarina equisetifolia, Albizia procera, Eucalyptus robusta, and two varieties of Leucaena leucocephala (an exotic and a native) were grown for maximum biomass production under the same climatic (1102 mm mean annual rainfall and 25°C mean annual air temperature) and edaphic conditions in the Lajas Valley of Puerto Rico (lat. 18°N., long. 67°W.). Management was intensive during early growth and establishment phases. Rates of large-branch/stem production (diameter ⩾ 2.5 cm) at age 5.5 years were 27.8, 20.4, 10.1, 7.7, and 5.5 t ha−1 year−1 for Casuarina, Albizia, Eucalyptus, exotic Leucaena, and native Leucaena, respectively. Stemwood biomass production of 40 tropical tree plantations established elsewhere for biomass production averaged 7.9 t ha−1 year−1. Species ranking in terms of total above-ground biomass and litter accumulation followed the same order. At age 5.5 years, the litter accumulation in plantations was (in the sale order): 16.2, 10.2, 11.8, 7.0, and 6.5 t ha−1. Thirty-five natural tropical forest stands averaged 6 t ha−1. Intensive management of fertile soils increases biomass yield of energy plantations, but not all species respond equally well to such treatments.

Original article : Kramm, G., Dlugi, R. and Lenschow, D.H., 1995. J. Hydrol., 166: 283-293.

The divergence maximum of 96 pairs of eyes was measured by noting the greatest prism, base in, through which binocular single vision could be maintained when the test object was held 5 M. 50, 33, and 25 centimeters from the base line of convergence. It was found that the maximum possible divergence of the optic axes of the eyes is greater when the eyes accommodate for a short distance than for a longer one. The divergence is proportional to that portion of the entire accommodative power which is used for the distance of fixation. This is demonstrated by the practical identity of the graphs representing the two functions of each of 79 of the 96 patients who were studied. Read before the American Ophthalmological Society at Lucerne, Canada, July, 1934.

A statistical analysis of sudden unexpected deaths in infants in relationto race and economic status is presented. The population of Philadelphia was divided by census tracts, according to information derived from the 1960 census, into 3 categories: one of low economic status, one of moderate economic status, and one of high economic status. The incidence of sudden deaths among infants in each category was determined and expressed per 1,000 live births and per 100 deaths of infants. Sudden deaths in infancy occurred significantly more frequently among non-Caucasians than Caucasians and among the poorer segments of the population than among those with high incomes, regardless of race.

This paper reports two cases in which vessels and connective tissue formations in the vitreous were presumably caused by preceding intraocular hemorrhage. Interesting facts noted in connection with such cases as published in the literature are discussed.

In the first case reported, the patient noticed increase in the size of a nevus, and the eye was hyperemia A histological description of the excised mass is given. Several other nevi were left alone because they did not show signs of active growth, and this procedure seems to be in accord with the views of other writers. The controversy as to the epithelial or connective tissue origin of nevi is briefly considered. Read before the American Ophthalmological Society, April 30 to May 2, 1928.