274 research outputs found
The Velocipede Craze in Maine
In early 1869 when the nation experienced its first bicycle craze, Maine was among the hardest-hit regions. Portland boasted one of the first and largest manufactories, and indoor rinks proliferated statewide in frenzied anticipation of the dawning “era of road travel. ” In this article, the author traces the movement in Maine within an international context and tackles the fundamental riddle: Why was the craze so intense, and yet so brief? He challenges the conventional explanation - that technical inadequacies doomed the machine - and cites economic obstacles: in particular, the unreasonable royalty demands imposed by Maine-born patent-holder Calvin Witty. David V. Herlihy holds a B.A. in the history of science from Harvard University. A specialist on bicycle history, he is a free-lance writer based in Boston. His works have appeared in a number of noted magazines, and he is currently preparing a book on Pierre Lallement and the invention of the bicycle
Detection of skewed X-chromosome inactivation in Fragile X syndrome and X chromosome aneuploidy using quantitative melt analysis.
Methylation of the fragile X mental retardation 1 (FMR1) exon 1/intron 1 boundary positioned fragile X related epigenetic element 2 (FREE2), reveals skewed X-chromosome inactivation (XCI) in fragile X syndrome full mutation (FM: CGGÂ >Â 200) females. XCI skewing has been also linked to abnormal X-linked gene expression with the broader clinical impact for sex chromosome aneuploidies (SCAs). In this study, 10 FREE2 CpG sites were targeted using methylation specific quantitative melt analysis (MS-QMA), including 3 sites that could not be analysed with previously used EpiTYPER system. The method was applied for detection of skewed XCI in FM females and in different types of SCA. We tested venous blood and saliva DNA collected from 107 controls (CGGÂ <Â 40), and 148 FM and 90 SCA individuals. MS-QMA identified: (i) most SCAs if combined with a Y chromosome test; (ii) locus-specific XCI skewing towards the hypomethylated state in FM females; and (iii) skewed XCI towards the hypermethylated state in SCA with 3 or more X chromosomes, and in 5% of the 47,XXY individuals. MS-QMA output also showed significant correlation with the EpiTYPER reference method in FM males and females (PÂ <Â 0.0001) and SCAs (PÂ <Â 0.05). In conclusion, we demonstrate use of MS-QMA to quantify skewed XCI in two applications with diagnostic utility
Effect of equine chorionic gonadotropin treatment during a progesterone-based timed artificial insemination program on reproductive performance in seasonal-calving lactating dairy cows
peer-reviewedThe aim of this study was to investigate the effect of progesterone (P4)-based timed artificial insemination (TAI) programs on fertility in seasonal-calving, pasture-based dairy herds. A total of 1,421 lactating dairy cows on 4 spring-calving farms were stratified based on days in milk (DIM) and parity and randomly allocated to 1 of 3 treatments: (1) control: no hormonal treatment; cows inseminated at detected estrus; (2) P4-Ovsynch: cows received a 7-d P4-releasing intravaginal device (PRID Delta; CEVA Santé Animale, Libourne, France) with 100 μg of a gonadotropin-releasing hormone (GnRH) analog (Ovarelin; CEVA Santé Animale) at PRID insertion, a 25-mg injection of PGF2α (Enzaprost; CEVA Santé Animale) at PRID removal, GnRH at 56 h after device removal and TAI 16 h later; (3) P4-Ovsynch+eCG: the same as P4-Ovsynch, but cows received 500 IU of equine chorionic gonadotropin (eCG; Syncrostim; CEVA Santé Animale) at PRID removal. At 10 d before mating start date (MSD), all cows that were ≥35 DIM were examined by transrectal ultrasound to assess presence or absence of a corpus luteum; body condition score (BCS) was also recorded. Pregnancy diagnosis was performed by transrectal ultrasonography 30 to 35 d after insemination. Overall pregnancy/AI (P/AI) was not different between groups (50.9, 49.8, and 46.3% for control, P4-Ovsynch, and P4-Ovsynch+eCG, respectively) but the 21-d pregnancy rate was increased by the use of synchronization (35.0, 51.7, and 47.2%, respectively). Compared with the control group, synchronization significantly reduced the interval from MSD to conception (34.6, 23.0, and 26.5 d, respectively) and consequently reduced the average days open (98.0, 86.0, and 89.0 d). Across all treatment groups, DIM at the start of synchronization affected P/AI (42.3, 49.5, and 53.9% for 80 DIM, respectively), but neither parity (46.5, 50.4, and 48.4% for parity 1, 2, and ≥3, respectively) nor BCS (44.0, 49.4, and 58.6% for ≤2.50, 2.75–3.25, and ≥3.50, respectively) affected the likelihood of P/AI. Two-way interactions between treatment and DIM, parity, or BCS were not detected. In conclusion, the use of TAI accelerated pregnancy establishment in cows in a pasture-based system by reducing days open, but eCG administration at PRID removal did not affect P/AI
Jewels across the Landscape: Monitoring and Assessing the Quality of Lakes and Reservoirs in the United States
An early naturalist described lakes as “jewels” across the landscape and indeed they were…at the end of the nineteenth century. As we settled the country and began to utilize the lake resource for our needs, things changed. Additionally, our needs for water brought about the construction of impoundments from ice ponds to small stock ponds up to mainstem impoundments along our major rivers. The lake resource in the United States now includes natural lakes in our northern tier of states, unique physiographic regions such as Florida and the Sand Hills of Nebraska, and the mountainous regions, and impoundments scattered across the entire landscape. In this chapter, we will describe efforts by an unique partnership between the individual states and tribal nations of the USA and the US Environmental Protection Agency to monitor and assess these systems. These efforts go beyond single water quality (chemistry) issues and include assessments targeting the goal of the Clean Water Act, namely, restoring, maintaining, and protecting the chemical, physical, and biological integrity of the nation’s lakes and reservoirs
Rivers and Streams: Upgrading Monitoring of the Nation’s Freshwater Resources - Meeting the Spirit of the Clean Water Act
The goal of the Clean Water Act (CWA) is to restore and maintain the chemical, physical and biological integrity of the waters in the United States. Much of the monitoring and assessment is reasonably delegated to the States to monitor and report the condition of their water to Congress through the Environmental Protection Agency. States have historically been fully occupied in monitoring the most egregious water quality problems along with select high priority water bodies. This approach, while addressing State priorities with finite resources, does not capture the full spectrum and scope of water quality conditions within and across State boundaries. Hence, the reporting on progress in meeting the goals of the CWA has not been realized. In this chapter, we describe the partnership between EPA, the States and Tribes to remedy this information gap for rivers and streams. Filling this gap requires both improved monitoring designs to reflect conditions across all waters as well as the expansion of indicators to move beyond water chemistry to include all three elements of the CWA goal—chemical, physical and biological integrity
Induction of Group IVC Phospholipase A2 in Allergic Asthma: Transcriptional Regulation by TNF-α in Bronchoepithelial Cells
Airway inflammation in allergen-induced asthma is associated with eicosanoid release. These bioactive lipids exhibit anti- and pro-inflammatory activities with relevance to pulmonary pathophysiology. We hypothesized that sensitization/challenge using an extract from the ubiquitous fungus, Aspergillus fumigatus (Af), in a mouse model of allergic asthma would result in altered phospholipase gene expression, thus modulating the downstream eicosanoid pathway. We observed the most significant induction in the group IVC phospholipase A2 (cPLA2γ or PLA2G4C). Our results infer that Af extract can induce cPLA2γ levels directly in eosinophils while induction in lung epithelial cells is most likely a consequence of TNF-α secretion by Af-activated macrophages. The mechanism of TNF-α-dependent induction of cPLA2γ gene expression was elucidated through a combination of promoter deletions, ChIP and overexpression studies in human bronchoepithelial cells, leading to the identification of functionally relevant CRE, NF-κB and E-box promoter elements. ChIP analysis demonstrated that RNA polymerase II, c-Jun/ATF-2, p65/p65 and USF1/USF2 complexes are recruited to the cPLA2γ enhancer/promoter in response to TNF-α with overexpression and dominant negative studies implying a strong level of cooperation and interplay between these factors. Overall, our data link cytokine-mediated alterations in cPLA2γ gene expression with allergic asthma and outline a complex regulatory mechanism
New Mandates and Imperatives in the Revised ACA Code of Ethics
The first major revision of the ACA Code of Ethics in a decade occurred in late 2005, with the updated edition containing important new mandates and imperatives. This article provides interviews with members of the Ethics Revision Task Force that flesh out seminal changes in the revised ACA Code of Ethics in the areas of confidentiality, romantic and sexual interactions, dual relationships, end-of-life care for terminally ill clients, cultural sensitivity, diagnosis, interventions, practice termination, technology, and deceased clients
Virtual Machine Support for Many-Core Architectures: Decoupling Abstract from Concrete Concurrency Models
The upcoming many-core architectures require software developers to exploit
concurrency to utilize available computational power. Today's high-level
language virtual machines (VMs), which are a cornerstone of software
development, do not provide sufficient abstraction for concurrency concepts. We
analyze concrete and abstract concurrency models and identify the challenges
they impose for VMs. To provide sufficient concurrency support in VMs, we
propose to integrate concurrency operations into VM instruction sets.
Since there will always be VMs optimized for special purposes, our goal is to
develop a methodology to design instruction sets with concurrency support.
Therefore, we also propose a list of trade-offs that have to be investigated to
advise the design of such instruction sets.
As a first experiment, we implemented one instruction set extension for
shared memory and one for non-shared memory concurrency. From our experimental
results, we derived a list of requirements for a full-grown experimental
environment for further research
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