Three Approaches to the Study of Language and Gender

Gender across Languages: The Linguistic Representation of Women and Men. Vol. 2. Marlis Hellinger and Hadumod Bußmann eds. Amsterdam: John Benjamins, 2002. 348 pp.
Gender Identity and Discourse Analysis. Lia Litosseliti and Jane Sunderland eds. Amsterdam: John Benjamins, 2002. 335 pp.
Talking Gender and Sexuality. Paul McIlvenny. ed. Amsterdam: John Benjamins, 2002. 327 pp.     

Waddington redux: models and explanation in stem cell and systems biology

Stem cell biology and systems biology are two prominent new approaches to studying cell development. In stem cell biology, the predominant method is experimental manipulation of concrete cells and tissues. Systems biology, in contrast, emphasizes mathematical modeling of cellular systems. For scientists and philosophers interested in development, an important question arises: how should the two approaches relate? This essay proposes an answer, using the model of Waddington’s landscape to triangulate between stem cell and systems approaches. This simple abstract model represents development as an undulating surface of hills and valleys. Originally constructed by C. H. Waddington to visually explicate an integrated theory of genetics, development and evolution, the landscape model can play an updated unificatory role. I examine this model’s structure, representational assumptions, and uses in all three contexts, and argue that explanations of cell development require both mathematical models and concrete experiments. On this view, the two approaches are interdependent, with mathematical models playing a crucial but circumscribed role in explanations of cell development.     

Human λ light chain locus: Organization and DNA sequences of three genomicJ regions

Evidence for the genomic organization of human lambda light chain joining (J) region gene segments is presented. A mouse J probe was used in Southern hybridizations to localize joining region sequences in a cosmid clone containing the genomic cluster of six human lambda constant (C) region gene segments. The results of these hybridizations suggest the presence of at least one J gene segment upstream from each constant region gene segment. The DNA sequences indicate that the human JI, J2, and J3 gene segments have consensus nonamer and heptamer sequences, proposed to be involved in V-J joining, are capable of encoding the known amino acid sequences for the respective J peptides, and have a sequence which could give functional RNA splice site at the end of their coding regions. Our data show that a single functional J is located 1.3 or 1.6 kb upstream of each of the C gene segments known to encode the Mcg, Kern^– Oz^–, and Kern^–Oz⁺ isotypes. Therefore, the gene organization of this region of the human lambda locus is J1 CI -J2C2-J3C3. The DNA sequences ofJ 1,J 2, andJ 3 presented in this paper establish that a singleJ gene segment precedes each expressed C gene segment, and support a model for the evolution of the human JC clusters where JICI andJ2C2-J3C3. arose from different ancestral JC units.     

Comparison of LDH-B4 allozymes of macrourids (Teleostei: Gadiformes) by electrophoresis and peptide mapping

The heart-type lactate dehydrogenase (LDH-_B4) homologs of two species of Nezumia and eight species of Coryphaenoides are isomobile on two commonly used electrophoretic buffer systems. To test the hypothesis that the homologs possess the same primary structures, the allozymes from N. bairdii and four species of Coryphaenoides were purified by affinity chromatography on an oxamate aminohexyl Sepharose column and digested with trypsin. The resulting peptide mixtures were then mapped using reversed-phase high-performance liquid chromatography. The peptide maps of the enzyme homologs indicate that the overall similarity of the homologs is high, but unique peptides in each species indicate that the allozymes are not identical in primary structure.     

The response of a bumblebee goby,Brachygobius sabanus,to chemical stimuli from injured conspecifics

Synopsis Brachygobius sabanus move less often and spend less time swimming when they detect chemicals released from injured conspecifics. This resembles the alarm response found in ostariophysan fishes, darters, and at least one other gobiid. Chemicals from injured Poecilia reticulata do not induce an alarm response in B. sabanus.     

Primary cultures of rat pancreatic acinar cells in serum-free medium

Summary Rat pancreatic acinar cells were isolated and cultured in Ham's F12 medium with 15% bovine calf serum. Caerulein, insulin, somatostatin, and dexamethasone (DEX) had no effect on intracellular or secreted amylase in these cultured cells. A serum-free medium, using Waymouth's MB 752/1 supplemented with albumin, epidermal growth factor (EGF), DEX, and HEPES, was then developed to avoid serum factors that might mask hormonal effects. In this SF medium, pancreatic acinar, cells maintained the morphological and ultrastructural characteristics of freshly isolated cells and secreted amylase in response to the secretagogue, carbamyl choline. Insulin, at a concentration of 1 μg/ml, significantly increased intracellular and secreted amylase activity after 3 d. This model cell system can be used to study the regulation of the synthesis of amylase and other pancreatic enzymes in vitro.     

Purification and characterization of maize ribulose-1,5-bisphosphate carboxylase

The ribulose-1,5-bisphosphate carboxylase/oxygenase purified from maize (a C₄ monocot) to homogeneity has a MW of532 000 and sedimentation coeffici