Does leaf gas exchange correlate with petiole xylem structural traits in Ulmus laevis seedlings under well-watered and drought stress conditions?

Several studies have shown that petiole xylem structure could be an important predictor of leaf gas exchange capacity, but the question of how petiole xylem structure relates to leaf gas exchange under different environment conditions remains unresolved. Moreover, knowledge of the amount of leaf gas exchange and structural variation that exists within a single species is also limited. In this study, we investigated the intraspecies coordination of leaf gas exchange and petiole xylem traits in 2-year-old seedlings of Ulmus laevis Pall.

Multiple, large deletions in rat mitochondrial DNA: evidence for a major hot spot.

This study identified 33 different deletions in mitochondrial DNA from four aging Fischer-344 rat brains and from a cultured rat lymphoma cell line (Nb2 cells). The deletions were located in the longer arc between the heavy and light strand origins of replication. PCR products that spanned across the deleted regions were sequenced, and deletions ranging between 6548 bp and 9977 bp in length were identified.

Inheritance of brachydactyly type D.

Inheritance of brachydactyly type D (BD-D) was studied in two unreported Caucasian family pedigrees and in 36 previously reported family pedigrees. The inheritance pattern was characteristic of a single autosomal dominant gene with incomplete penetrance. Using the proportion of individuals exhibiting the trait as the index, penetrance was sex influenced, being complete in females and approximately 62 percent in males.

Desired family size and sex of children in Nigeria.

During 1981, sex ratio data and preferences for family size and for combinations and permutations of children were provided by 333 Nigerian students at the University of Ilorin, Ilorin, Nigeria. For the present and parental generations combined, the secondary sex ratio was estimated to be 95.8 males:100 females.

Distribution of sexes in cattle.

Data were obtained from records of 1,046 Holstein dams included in the dairy herd at Cornell University during the years 1940 through 1977. Sex by order of parity was determined for the offspring of each dam. The overall sex ratio for 4,245 single parities was 52.

Desired family size and sex of children in Botucatu, Brazil.

During 1977--78, 715 unmarried college students at the Universidade Estadual Paulista, Botucatu, Brazil, were surveyed for their preferences for family sizes and combinations and permutations of sexes of children. The most preferred family size by both male and female respondents was two children. A slightly lower proportion of respondents preferred a family size of three children.