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"Davis, Barbara"
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iQOS: evidence of pyrolysis and release of a toxicant from plastic
ObjectiveTo evaluate performance of the I quit original smoking (iQOS) heat-not-burn system as a function of cleaning and puffing topography, investigate the validity of manufacturer’s claims that this device does not burn tobacco and determine if the polymer-film filter is potentially harmful.MethodsiQOS performance was evaluated using five running conditions incorporating two different cleaning protocols. Heatsticks were visually and stereomicroscopically inspected preuse and postuse to determine the extent of tobacco plug charring (from pyrolysis) and polymer-film filter melting, and to elucidate the effects of cleaning on charring. Gas chromatography–mass spectrometry headspace analysis was conducted on unused polymer-film filters to determine if potentially toxic chemicals are emitted from the filter during heating.ResultsFor all testing protocols, pressure drop decreased as puff number increased. Changes in testing protocols did not affect aerosol density. Charring due to pyrolysis (a form of organic matter thermochemical decomposition) was observed in the tobacco plug after use. When the manufacturer’s cleaning instructions were followed, both charring of the tobacco plug and melting of the polymer-film filter increased. Headspace analysis of the polymer-film filter revealed the release of formaldehyde cyanohydrin at 90°C, which is well below the maximum temperature reached during normal usage.DiscussionDevice usage limitations may contribute to decreases in interpuff intervals, potentially increasing user’s intake of nicotine and other harmful chemicals. This study found that the tobacco plug does char and that charring increases when the device is not cleaned between heatsticks. Release of formaldehyde cyanohydrin is a concern as it is highly toxic at very low concentrations.
Journal Article
Love, Alice
\"From the author of Summer at Hideaway Key comes a sweeping new Southern women's fiction novel about forgiving the past one letter at a time. The truth lies between the lines. A year ago, Dovie Larkin's life was shattered when her fiance committed suicide just weeks before their wedding. Now, plagued by guilt, she has become a fixture at the cemetery where William is buried, visiting his grave daily, waiting for answers she knows will never come. Then one day, she sees an old woman whose grief mirrors her own. Fascinated, she watches the woman leave a letter on a nearby grave. Dovie ignores her conscience and reads the letter a mother's plea for forgiveness to her dead daughter -and immediately needs to know the rest of the story. As she delves deeper, a collection of letters from the cemetery's lost and found begins to unravel a decades-old mystery involving one of Charleston's wealthiest families. But even as Dovie seeks to answer questions about another woman's past questions filled with deception, betrayal, and heartbreaking loss she starts to discover the keys to love, forgiveness, and finally embracing the future
Book
Evaluation of long-chain omega-3 canola oil on Atlantic salmon growth, performance, and essential fatty acid tissue accretion across the life cycle: a review
Aquaculture plays an important role in providing protein and fatty acids to meet human nutritional requirements. The finite supply of marine ingredients has led to increased use of vegetable oils in aquafeed. While these oils can meet energy and growth needs, they lack nutritionally required ω3 long-chain polyunsaturated fatty acids (ω3 LCPUFAs). Development of land-based alternative oil sources to safeguard global aquaculture production, while meeting the nutritional needs of both fish and human consumers, is critical. This review summarizes studies using a new land-based ω3 LCPUFA canola oil in fish feed to support both energy and ω3 LCPUFA requirements of Atlantic salmon during each phase of the life cycle, while producing fish with adequate ω3 LCPUFA content to meet human nutritional needs. In all cases, growth and performance were comparable to fish fed conventional fish-oil-based diets; no adverse effects were attributed to the use of ω3 canola oil. Fatty acid deposition in muscle (fillet) reflected feed composition, resulting in accumulation of alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) and a low ω6:ω3 ratio, making salmon fed ω3 LCPUFA canola oil a sustainable source of these nutrients for human consumption. Additionally, reduced melanin deposits were observed in fish fed ω3 LCPUFA canola oil.
Journal Article
Grizzly boy
Tired of rules, a young boy decides to be a wild and free bear but soon runs into obstacles.
Book
Revisiting frequencies of phonological sound classes in speech input: Change over time in child-directed speech
The purpose of the current study was to revisit a controversial topic: whether frequencies of phonological consonant and vowel classes differ in speech directed to children and to adults. In addition, the current study investigated whether the frequency of phonological consonant and vowel classes changes with children’s increasing chronological and/or developmental age. This study analyzed speech input from 44 adults to four different age groups of listeners (i.e., three groups of children at 6, 18, and 36 months of age and one group of adult listeners) in terms of frequency of occurrence of consonant and vowel classes. Results revealed that consonant stop, nasal, fricative and glide manner classes as well as all four consonant place classes were significantly different in speech directed to the four different age groups. A perspective is discussed to better understand the nature of frequency input of phonological sound classes.
Journal Article
Stubby the fearless squid
Stubby, a timid squid, and Razor Clam become pen pals, exchanging fanciful tales of their courageous acts, but when they meet, Stubby's brave imaginings are put to the test.
Book
Mechanisms of Phthalate Ester Toxicity in the Female Reproductive System
Phthalates are high-production-volume synthetic chemicals with ubiquitous human exposures because of their use in plastics and other common consumer products. Recent epidemiologic evidence suggests that women have a unique exposure profile to phthalates, which raises concern about the potential health hazards posed by such exposures. Research in our laboratory examines how phthalates interact with the female reproductive system in animal models to provide insights into the potential health effects of these chemicals in women. Here we review our work and the work of others studying these mechanisms and propose a model for the ovarian action of di-(2-ethylhexyl) phthalate (DEHP). In vivo, DEHP (2 g/kg) causes decreased serum estradiol levels, prolonged estrous cycles, and no ovulations in adult, cycling rats. In vitro, monoethylhexyl phthalate (MEHP; the active metabolite of DEHP) decreases granulosa cell aromatase RNA message and protein levels in a dose-dependent manner. MEHP is unique among the phthalates in its suppression of aromatase and in its ability to activate peroxisome proliferator-activated receptors (PPARs). We hypothesize that MEHP activates the PPARs to suppress aromatase in the granulosa cell. MEHP-, PPARα-, and PPARγ-specific ligands all similarly decreased estradiol production and RNA message levels of aromatase in vitro. Our model shows that MEHP acts on the granulosa cell by decreasing cAMP stimulated by follicle stimulating hormone and by activating the PPARs, which leads to decreased aromatase transcription. Thus, the environmental contaminant DEHP, through its metabolite MEHP, acts through a receptor-mediated signaling pathway to suppress estradiol production in the ovary, leading to anovulation.
Journal Article
Perinatally Administered Bisphenol A as a Potential Mammary Gland Carcinogen in Rats
Environmental exposure to bisphenol A (BPA) affects mammary gland development in rodents and primates. Prenatal exposure to environmentally relevant doses of BPA increased the number of intraductal hyperplasias and ductal carcinomas in situ by 50 days of age in Wistar-Furth rats.
We aimed to determine whether BPA exposure of dams during gestation only or throughout lactation affects the incidence of mammary gland neoplasia in female offspring.
We treated pregnant Sprague-Dawley rats with BPA at 0, 0.25, 2.5, 25, or 250 μg BPA/kg BW/day from gestational day (GD) 9 to birth and from GD9 to postnatal day (PND) 21. Mammary glands from BPA-exposed offspring were examined at four time points for preneoplastic and neoplastic lesions. To assess circulating BPA levels, we exposed pregnant rats to vehicle or 250 μg BPA/kg BW/day during gestation only or during gestation/lactation and analyzed sera from dams, fetuses, and nursing pups for total and unconjugated BPA.
Total and unconjugated BPA were detected in sera from 100% of dams and fetuses and 33% of pups exposed to 250 μg BPA/kg BW/day. Unconjugated BPA levels in exposed dams and fetuses (gestational) and in exposed dams and pups (gestational/lactational) were within levels found in humans. Preneoplastic lesions developed in BPA-exposed female offspring across all doses as early as PND50. Unexpectedly, mammary gland adenocarcinomas developed in BPA-exposed offspring by PND90.
Our findings suggest that developmental exposure to environmentally relevant levels of BPA during gestation and lactation induces mammary gland neoplasms in the absence of any additional carcinogenic treatment. Thus, BPA may act as a complete mammary gland carcinogen.
Journal Article