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Research has consistently shown diversity of vocabulary to be an important indicator of second language (L2) writing development as well as L2 writing performance. These studies underscore the importance of vocabulary to L2 writing. However, they provide little to indicate what kind of vocabulary learners of English may need to know in order to develop writing proficiency. This small-scale pilot study examined the relationships among vocabulary knowledge, vocabulary use, and L2 writing performance. The results suggest that accurate productive knowledge of high-frequency word families was associated with L2 writing performance. However, actual use of high-frequency word families was negatively associated with L2 writing performance. Based on the results, the authors present potential uses of lexical frequency information to help students develop (a) accurate productive knowledge of high-frequency word families and (b) a repertoire of low-frequency word families based on their communicative needs.

Polyol sweeteners, including erythritol and xylitol, have been investigated for their potential in insect control against a number of pests including mosquitoes, fruit flies, ants, and filth flies. Several insecticidal modes of action for the polyols have been proposed in non-biting flies and include: (1) dehydration from excessive regurgitation, (2) arrestment of physiological processes due to abnormally high hemolymph osmolality or osmotic diarrhea, and (3) alteration of the gut microbiome. Here, we explored the proposed modes of action in the house fly, Musca domestica L. (Diptera: Muscidae), a non-biting fly of medical and veterinary importance. House flies fed erythritol or xylitol regurgitated at a significantly higher rate when compared to flies that ingested sucrose. Flies that ingested sucrose solutions had higher hemolymph osmolality than erythritol but not xylitol, and deposited significantly more fecal spots than flies fed polyol solutions. Cultivable bacteria were least abundant in flies fed solutions of either sucrose or xylitol and most abundant in control flies provided water only. Of the potential modes of action tested, physiological stress from excessive post-feeding regurgitation seems the likeliest cause of death related to polyol consumption. However, we cannot rule out a classical toxicological or biochemical mode of action from these results. Although the efficacy of polyols as active ingredients is still under debate, their use as other components in fly control products may be beneficial. Due to widespread resistance to a limited number of insecticidal chemicals registered for house fly control, it is important that new control chemicals be thoroughly assessed for usefulness.

Multiple studies on the relationship between lexical diversity and holistic writing quality in a second language (L2) have consistently shown that a greater number of unique lexical items, compared to the total number of words, is associated with better quality writing. The findings of such studies indicate the importance of vocabulary to L2 writing. However, they provide little information in terms of what vocabulary L2 writers need to learn in order to improve their writing. Despite its limited application in the mid to late 1990s, the use of lexical frequency profiles has not been developed as a method for analyzing the vocabulary of L2 writers’ texts and providing insight as to the vocabulary needed for developing L2 writers. This study constructed two lexical frequency profiles of texts written by a homogeneous group of Spanish-speaking learners of English. Multiple regression analyses were conducted to determine the contribution of more and less frequent lexical items to the participants’ holistic scores. The results indicated that word types which occur less frequently in the English language contributed significantly to the participants’ holistic scores, despite the relatively low frequency with which they were used in the participants’ essays. These results suggest not only the utility of lexical frequency profiles in teaching and researching L2 writing, but also that L2 writers may benefit from instruction using frequency information. Pedagogical implications are discussed in terms of how L2 writing instructors can incorporate lexical frequency information into direct vocabulary instruction.

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