A contribution to spline-regression

Considered are polynomial spline-regressions by which functions with individual behaviour over parts of their domain may be approximated (in square mean) in a favourable manner by successive polynomials. Concerning the connections of the individual polynoms different conditions may be imposed as to continuity and smoothness. Beside of the calculation of the regression parameters essential results are the construction of confidence regions for the regression function and the formulation of tests for special dependence. Hints for practical application are given and a concrete example from agriculture is presented.     

A contribution to the world selenium map

Atomic absorption spectrophotometric method was used to determine the serum selenium levels of 86 healthy individuals. Variations in age, sex, and geographically different urban regions of Yugoslavia were investigated. A group of 63 healthy children, ages 8–15 yr, were examined. Mean±standard deviation of the serum selenium concentration was 57±9 μg/L; age and geographic area had no effect on the Se status of children, but the difference between boys and girls was significant (P<0.05). A group of 23 men from Zagreb, ages 22–37 yr, were examined. The group was divided into three age subgroups and no difference was found among these groups. The mean Se concentration was 69±18 μg/L, and a statistically significant difference was found only between the group of adults and the group of children (P<0.05).     

A contribution to the knowledge of liphistiid spiders

These spiders resemble fossil spiders of the Carboniferous. Although they are unique in retaining several primitive characters it is thought best to include them in the sub-Order Mygalomorphae and to abandon the special sub-Order Liphistiomorphae.
The family Heptathelidae to include those species with seven instead of eight spinnerets as in the Liphistiidae is also abandoned.
The species Liphistius thorelli Sim. from Sumatra is regarded as a synonym of the other Sumatran species L. sumatranus Thor.
Eight species of Liphistius and two of Heptathela are now recognized. Their distribution is confined, according to present knowledge, to Burma, Thailand, Vietnam, China, Japan, Malaysia and Sumatra. This may provide useful evidence in the question, as yet unsettled, of the origin of south-east Asia in terms of continental drift.
A special visit has been paid to Sumatra to rediscover Liphistius sumatranus (of which only one specimen was found and described in 1879) to establish with certainty that it is distinct from the Malaysian L. desultor . This was achieved and the species are now compared.
Some biological observations are provided.     

A contribution to Bontoc ethnobotany

This paper presents the basic data gathered in a study of plant names, uses, folklore, and cultivation practices among the residents of Tukukan in the central Bontoc region of the northern Philippines. Scientific names and phytogeographic statuses are provided for 325 specimens representing 265 genera and 109 families. In addition to expanding our knowledge of Bontoc ethnobotany, the study has provided insights into past plant use with important implications for understanding agricultural evolution in the region. Una Contributión a la Etnoboténica Bontoc. Presentamos en este articulo los datos recopilados en un estudio de los nombres, usos y cultivo de las plantas y su papel en las tradiciones orales de los residentes de Tukukan en la región Bontoc central en el norte de las Filipinos. Indicamos los nombres cientificos y las categorias fitogeogréficas de 325 ejemplares de herbario que representan 265 góneros en 109 familias. Ademés de aumentar nuestros conocimientos de la etnoboténica bontoc, este estudio nos permite profundizar en el conocimiento del antiguo uso de las plantas y sus implicaciones en la evolución agricola de la region.     

A contribution to the generalization of the Gompertz function

SCHARF (1976) discusses various growth models. For the Gompertz function the differential equation (Formula: see text) is used. In words: the difference between relative growth rate and relative growth acceleration is constant. On the other hand, according to WENK (1973), the differential equation (Formula: see text) applies to the Gompertz function. It can be shown mathematically that (Formula: see text) applies in general. From Eq. (2) one obtains without trouble (Formula: see text). Therefore, the property leading to the Gompertz function may be defined as follows; the logarithmic derivation of the relative growth rate is constant. Eq. (2) is applicable only in special cases. It can be extended by assuming that c is not constant, but a function of time. In this way, a great number of growth functions can be found, which have to be regarded as model-based extensions of the Gompertz function.     

A contribution to the serological typization of the rhizobia

1. (1)
   Гыли приготовлены антисыворотки против штаммов Rhizobium meliloti D 24, D 16, D 37 и D 23, Rhizobium leguminosarum D 1 и Rhizobium trifolii D 26.     
   
   

A contribution to the study ofChenopodium album agg

Plants gathered in Staré Brno (1979)—classified under the genusChenopodium L. and having K (2n)=54—are hybrids.Chenopodium strictum Roth (n=18) andChenopodium suecicum J. Murr (n=9) are probably parental species. Hybridization may have been linked with amphidiploidy.