74 research outputs found
Associations of Trying to Lose Weight, Weight Control Behaviors, and Current Cigarette Use Among US High School Students
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72289/1/j.1746-1561.2009.00421.x.pd
Concise Syntheses of Insect Pheromones Using Z-Selective Cross Metathesis
The use of insect sex pheromones to limit specifically targeted pest populations has gained increasing popularity as a viable, safe, and environmentally friendly alternative to insecticides. While broad-spectrum insecticides are toxic compounds that have been shown to adversely affect human health,[1] extensive studies have shown that insect pheromones are nontoxic and safe for human consumption at the levels used in pest control practices.[2] Female sex pheromones are mainly employed in pest control in a process termed mating disruption. This involves dispersing pheromones over a large area, overloading the sensory organs of male insects and preventing them from locating and mating with females who are releasing a much smaller amount of the same pheromone blends; this strategy has proven to reduce specific insect populations dramatically.[3] To date, the United States Environmental Protection Agency (EPA) has approved approximately twenty lepidopteran female sex pheromones as active ingredients for pest control.[2
Low Catalyst Loadings in Olefin Metathesis: Synthesis of Nitrogen Heterocycles by Ring-Closing Metathesis
A series of ruthenium catalysts have been screened under ring-closing metathesis (RCM) conditions to produce five-, six-, and seven-membered carbamate-protected cyclic amines. Many of these catalysts demonstrated excellent RCM activity and yields with as low as 500 ppm catalyst loadings. RCM of the five-membered carbamate series could be run neat, the six-membered carbamate series could be run at 1.0 M, and the seven-membered carbamate series worked best at 0.2−0.05 M
Testing the preservation potential of early diagenetic dolomites as geochemical archives
Early marine diagenetic dolomite is a rather thermodynamically‐stable carbonate phase and has potential to act as an archive of marine porewater properties. However, the variety of early to late diagenetic dolomite phases that can coexist within a single sample can result in extensive complexity. Here, the archive potential of early marine dolomites exposed to extreme post‐depositional processes is tested using various types of analyses, including: petrography, fluid inclusion data, stable δ13C and δ18O isotopes, 87Sr/86Sr ratios, and U‐Pb age dating of various dolomite phases. In this example, a Triassic carbonate platform was dissected and overprinted (diagenetic temperatures of 50 to 430°C) in a strike‐slip zone in Southern Spain. Eight episodes of dolomitization, a dolostone cataclasite and late stage meteoric/vadose cementation were recognized. The following processes were found to be diagenetically relevant: (i) protolith deposition and fabric‐preservation, and marine dolomitization of precursor aragonite and calcite during the Middle–Late Triassic; (ii) intermediate burial and formation of zebra saddle dolomite and precipitation of various dolomite cements in a Proto‐Atlantic opening stress regime (T ca 250°C) during the Early–Middle Jurassic; (iii) dolomite cement precipitation during early Alpine tectonism, rapid burial to ca 15 km, and high‐grade anchizone overprint during Alpine tectonic evolution in the Early Eocene to Early Miocene; (iv) brecciation of dolostones to cataclasite during the onset of the Carboneras Fault Zone activity during the Middle Miocene; and (v) late‐stage regression and subsequent meteoric overprint. Data shown here document that, under favourable conditions, early diagenetic marine dolomites and their archive data may resist petrographic and geochemical resetting over time intervals of 108 or more years. Evidence for this preservation includes preserved Late Triassic seawater δ13CDIC values and primary fluid inclusion data. Data also indicate that oversimplified statements based on bulk data from other petrographically‐complex dolomite archives must be considered with caution
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Grazing and production by zooplankton in lakes of the Cedar River watershed
Zooplankton grazing rates and life history stage densities for secondary
production estimates were determined in three lakes in the Cedar River
watershed, Washington. Eight copepod species, seven cladoceran and nine
rotifer species were identified in the three lakes. No one species of
cladoceran or copepod occurred in all the lakes, but the rotifers are
common throughout. Copepods in the lakes showed no clear diet migration,
while two cladocerans did migrate. Copepods were most important numerically
in the lakes. Some principal members were Diaptomus ashZandi which
reached a seasonal maximum adult density of 11/2 (mean of water column) in
Lake Sammamish and LimnocaZanus in Chester Morse which reached a maximum
of 0.7/2. Two Diaptomus species are Important in Findley Lake. Densities
averaged about 10 times greater in Sammamish than in the two oligotrophic
lakes. Data on population dynamics from the egg ratio technique are given
for the common cladocerans in the three lakes.
Grazing of phytoplankton by zooplankton stimulated photosynthetic carbon
uptake in the light in excess of 200 percent over ungrazed populations.
Phytoplankton loss rates from grazing ranged from 0.002 to 0.268 pg chi a/
animal day. Feeding was found to be maximum at low concentrations of algae.
These rates account for from 2-247 percent of the average growing season
productivity in the lakes. Net plankton (>500 were seldom grazed and since
that size fraction and algal mass in general increased with mean productivity
and nutrient content in the lakes such decreasing efficiency in food
transfer is seen as a major effect of eutrophication
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Grazing and production by zooplankton in lakes of contrasting trophic status : a progress report
Grazing rates and density of the crustacean zooplankton were measured
in Findley and Chester Morse Lakes and Lake Sammamish, Washington.
Sample analysis is incomplete at reporting time, thus estimates of
production from examination of life stage biomass changes was not possible.
Maximum density of crustacean zooplankton was about 10/1 in
the water column of oligotrophic Findley and Chester Morse Lakes and
70/1 in mesotrophic-eutrophic Lake Sammamish during 1972. Densities
averaged about 10 times greater in Lake Sammamish than in the other
lakes. Copepods comprised most of the numbers in all three lakes.
Grazing apparently represents a sizable loss to phytoplankton in the
three lakes feeding rates experimentally determined in situ from
changes in ¹⁴C tagged phytoplankton ranged from nearly one half to
over six times the algal biomass per day. However, feeding rate was
always less than phytoplankton productivity
Self-love and sociability: the ‘rudiments of commerce’ in the state of nature
Istvan Hont’s classic work on the theoretical links between the seventeenth-century natural jurists Hugo Grotius and Samuel Pufendorf and the eighteenth-century Scottish political economists remains a popular trope among intellectual and economic historians of various stamps. Despite this, a common criticism levelled at Hont remains his relative lack of engagement with the relationship between religion and economics in the early modern period. This paper challenges this aspect of Hont’s narrative by drawing attention to an alternative, albeit complementary, assessment of the natural jurisprudential heritage of eighteenth-century British political economy. Specifically, the article attempts to map on to Hont’s thesis the Christian Stoic interpretation of Grotius and Pufendorf which has gained greater currency in recent years. In doing so, the paper argues that Grotius and Pufendorf’s contributions to the ‘unsocial sociability’ debate do not necessarily lead directly to the Scottish school of political economists, as is commonly assumed. Instead, it contends that a reconsideration of Grotius and Pufendorf as neo-Stoic theorists, particularly via scrutiny of their respective adaptations of the traditional Stoic theory of oikeiosis, steers us towards the heart of the early English ‘clerical’ Enlightenment
Neonatal Handling Affects Durably Bonding and Social Development
The neonatal period in humans and in most mammals is characterized by intense mother-young interactions favoring pair bonding and the adaptation of neonates to their new environment. However, in many post-delivery procedures, human babies commonly experience combined maternal separation and intense handling for about one hour post-birth. Currently, the effects of such disturbances on later attachment and on the development of newborns are still debated: clearly, further investigations are required. As animals present good models for controlled experimentation, we chose domestic horses to investigate this issue. Horses, like humans, are characterized by single births, long lactating periods and selective mother-infant bonds. Routine postnatal procedures for foals, as for human babies, also involve intense handling and maternal separation. In the present study, we monitored the behavior of foals from early stages of development to “adolescence”, in a normal ecological context (social groups with adults and peers). Experimental foals, separated from their mothers and handled for only 1 hour post-birth, were compared to control foals, left undisturbed after birth. Our results revealed short- and long-term effects of this unique neonatal experience on attachment and subsequent social competences. Thus, experimental foals presented patterns of insecure attachment to their mothers (strong dependence on their mothers, little play) and impaired social competences (social withdrawal, aggressiveness) at all ages. We discuss these results in terms of mother-young interactions, timing of interactions and relationships between bonding and subsequent social competences. Our results indicate that this ungulate species could become an interesting animal model. To our knowledge, this is the first clear demonstration that intervention just after birth affects bonding and subsequent social competences (at least until “adolescence”). It opens new research directions for studies on both humans and other animals
A large-scale genome-wide association study meta-analysis of cannabis use disorder
Summary Background Variation in liability to cannabis use disorder has a strong genetic component (estimated twin and family heritability about 50–70%) and is associated with negative outcomes, including increased risk of psychopathology. The aim of the study was to conduct a large genome-wide association study (GWAS) to identify novel genetic variants associated with cannabis use disorder. Methods To conduct this GWAS meta-analysis of cannabis use disorder and identify associations with genetic loci, we used samples from the Psychiatric Genomics Consortium Substance Use Disorders working group, iPSYCH, and deCODE (20 916 case samples, 363 116 control samples in total), contrasting cannabis use disorder cases with controls. To examine the genetic overlap between cannabis use disorder and 22 traits of interest (chosen because of previously published phenotypic correlations [eg, psychiatric disorders] or hypothesised associations [eg, chronotype] with cannabis use disorder), we used linkage disequilibrium score regression to calculate genetic correlations. Findings We identified two genome-wide significant loci: a novel chromosome 7 locus (FOXP2, lead single-nucleotide polymorphism [SNP] rs7783012; odds ratio [OR] 1·11, 95% CI 1·07–1·15, p=1·84 × 10−9) and the previously identified chromosome 8 locus (near CHRNA2 and EPHX2, lead SNP rs4732724; OR 0·89, 95% CI 0·86–0·93, p=6·46 × 10−9). Cannabis use disorder and cannabis use were genetically correlated (rg 0·50, p=1·50 × 10−21), but they showed significantly different genetic correlations with 12 of the 22 traits we tested, suggesting at least partially different genetic underpinnings of cannabis use and cannabis use disorder. Cannabis use disorder was positively genetically correlated with other psychopathology, including ADHD, major depression, and schizophrenia. Interpretation These findings support the theory that cannabis use disorder has shared genetic liability with other psychopathology, and there is a distinction between genetic liability to cannabis use and cannabis use disorder. Funding National Institute of Mental Health; National Institute on Alcohol Abuse and Alcoholism; National Institute on Drug Abuse; Center for Genomics and Personalized Medicine and the Centre for Integrative Sequencing; The European Commission, Horizon 2020; National Institute of Child Health and Human Development; Health Research Council of New Zealand; National Institute on Aging; Wellcome Trust Case Control Consortium; UK Research and Innovation Medical Research Council (UKRI MRC); The Brain & Behavior Research Foundation; National Institute on Deafness and Other Communication Disorders; Substance Abuse and Mental Health Services Administration (SAMHSA); National Institute of Biomedical Imaging and Bioengineering; National Health and Medical Research Council (NHMRC) Australia; Tobacco-Related Disease Research Program of the University of California; Families for Borderline Personality Disorder Research (Beth and Rob Elliott) 2018 NARSAD Young Investigator Grant; The National Child Health Research Foundation (Cure Kids); The Canterbury Medical Research Foundation; The New Zealand Lottery Grants Board; The University of Otago; The Carney Centre for Pharmacogenomics; The James Hume Bequest Fund; National Institutes of Health: Genes, Environment and Health Initiative; National Institutes of Health; National Cancer Institute; The William T Grant Foundation; Australian Research Council; The Virginia Tobacco Settlement Foundation; The VISN 1 and VISN 4 Mental Illness Research, Education, and Clinical Centers of the US Department of Veterans Affairs; The 5th Framework Programme (FP-5) GenomEUtwin Project; The Lundbeck Foundation; NIH-funded Shared Instrumentation Grant S10RR025141; Clinical Translational Sciences Award grants; National Institute of Neurological Disorders and Stroke; National Heart, Lung, and Blood Institute; National Institute of General Medical Sciences.Peer reviewe
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