Diatom Communites in the Cuyahoga River (USA): Changes in Species Composition Between 1974 and 1992 Following Renovations in Wastewater Management

Author Institution: Department of Biology, The University of AkronPeriphytic diatom communities along the Cuyahoga River were analyzed for possible changes in species composition resulting from improvements in wastewater management within the river basin during the past 18 years. The results, compared to a similar study conducted in 1974, and controlled for seasonality and microhabitat effects, show an increase in total diatom species (75 to 105), especially pollutionsensitive species, and a reduction in pollution-tolerant species—all indications of improved water quality. Reductions were evident in the number and proportion of pollution-tolerant species such as Gomphonema parvulum, Melosira varians, Navicula cryptocephala, N. pelliculosa, Nitzschia communis, N.palea, and Synedra ulna. The number and proportion of pollution-sensitive species such as Achnanthes linearis, Amphora pediculus, Cocconeis pediculus, Diatoma vulgare, Navicula tripunctata, and Nitzschia dissipata increased. Despite changes in species composition, headwaters of the river, managed as a domestic water supply and Ohio Scenic River, continue to support 2-3 X more taxa than the lower river below the City of Akron. Substantial degradation of water quality in the lower river persists despite recent restoration efforts. A major source of pollution occurs upstream from the Akron Water Pollution Control facility because sample sites above and below this facility were very similar in diatom species composition, each dominated by Nitzschia amphibia (-40%), a well known saprophilic diatom associated with organically polluted water. Overflows from combined stormwater-sanitary sewers, within the Akron metropolitan area are the most probable cause of the continued suppression of diatom species diversity

Competition for Pollination Between an Invasive Species (Purple Loosestrife) and a Native Congener

Invasive species are frequently regarded as Superlative competitors that can vegetatively crowd Out natives, but little is known about whether invasives call compete for pollination services with native plants. We hypothesized that, when the showy invasive species Lythrum salicaria (purple loosestrife) was present, pollinator visitation and seed set would be reduced in a native congener, L. alatum (winged loosestrife). To test this hypothesis, we constructed mixed and monospecific plots of the two species. Over two years of study, we found that L. salicaria significantly reduced both pollinator visitation and seed set in L. alatum. Furthermore, pollinators moved frequently between the two plant species, which may cause heterospecific pollen transfer. Thus, reductions in both pollen quantity and pollen quality may reduce L. alatum seed set. If similar patterns occur in the field, invasive plants may be an even greater threat to natives than previously thought

An Analysis of Texas Superintendents' Bilingual/ESL Teacher Recruitment and Retention Practices

An Analysis of Texas Superintendents’ Bilingual/ESL Teacher Recruitment and Retention Practice

Exploring Asian Female Pastors\u27 Leadership Roles in the Church: Using Deborah\u27s Story

Women in many Christian cultures are told that men are strong and should lead the church. Consequently, some women rationalize that they should not assume top leadership roles in the church. When they do assume such roles, many female pastors experience challenges. The purpose of our qualitative case study was to give voice to Asian female pastors (AFPs) by having them share challenges they experienced in the Taiwanese Presbyterian Church and relate those challenges to the experiences of Deborah in the biblical story found in Judges 4 and 5. Reported in this paper are the results of focus groups centered on a feminist commentary of Deborah\u27s story. The voices of the AFPs speak to reconstruct traditional patriarchal theological thought

An Analysis of a Public School Prekindergarten Bilingual Montessori Program

The purpose of our study was to analyze a public school prekindergarten Montessori bilingual program via the investigation of second grade reading achievement scores on a Spanish and an English norm-referenced test between two groups of students those who had participated in a prekindergarten Montessori bilingual program and those who had participated in a prekindergarten traditional bilingual program

FGF4 retrogene on CFA12 is responsible for chondrodystrophy and intervertebral disc disease in dogs.

Chondrodystrophy in dogs is defined by dysplastic, shortened long bones and premature degeneration and calcification of intervertebral discs. Independent genome-wide association analyses for skeletal dysplasia (short limbs) within a single breed (PBonferroni = 0.01) and intervertebral disc disease (IVDD) across breeds (PBonferroni = 4.0 × 10-10) both identified a significant association to the same region on CFA12. Whole genome sequencing identified a highly expressed FGF4 retrogene within this shared region. The FGF4 retrogene segregated with limb length and had an odds ratio of 51.23 (95% CI = 46.69, 56.20) for IVDD. Long bone length in dogs is a unique example of multiple disease-causing retrocopies of the same parental gene in a mammalian species. FGF signaling abnormalities have been associated with skeletal dysplasia in humans, and our findings present opportunities for both selective elimination of a medically and financially devastating disease in dogs and further understanding of the ever-growing complexity of retrogene biology

An Analysis of Texas Superintendents' Bilingual/ESL Teacher Recruitment and Retention Practices

An Analysis of Texas Superintendents’ Bilingual/ESL Teacher Recruitment and Retention Practice