The Pioneer Anomaly

Radio-metric Doppler tracking data received from the Pioneer 10 and 11 spacecraft from heliocentric distances of 20-70 AU has consistently indicated the presence of a small, anomalous, blue-shifted frequency drift uniformly changing with a rate of ~6 x 10^{-9} Hz/s. Ultimately, the drift was interpreted as a constant sunward deceleration of each particular spacecraft at the level of a_P = (8.74 +/- 1.33) x 10^{-10} m/s^2. This apparent violation of the Newton's gravitational inverse-square law has become known as the Pioneer anomaly; the nature of this anomaly remains unexplained. In this review, we summarize the current knowledge of the physical properties of the anomaly and the conditions that led to its detection and characterization. We review various mechanisms proposed to explain the anomaly and discuss the current state of efforts to determine its nature. A comprehensive new investigation of the anomalous behavior of the two Pioneers has begun recently. The new efforts rely on the much-extended set of radio-metric Doppler data for both spacecraft in conjunction with the newly available complete record of their telemetry files and a large archive of original project documentation. As the new study is yet to report its findings, this review provides the necessary background for the new results to appear in the near future. In particular, we provide a significant amount of information on the design, operations and behavior of the two Pioneers during their entire missions, including descriptions of various data formats and techniques used for their navigation and radio-science data analysis. As most of this information was recovered relatively recently, it was not used in the previous studies of the Pioneer anomaly, but it is critical for the new investigation.Comment: 165 pages, 40 figures, 16 tables; accepted for publication in Living Reviews in Relativit

Measuring enteric methane emissions from individual ruminant animals in their natural environment

Ruminant livestock are an important source of meat, milk, fiber, and labor for humans. The process by which ruminants digest plant material through rumen fermentation into useful product results in the loss of energy in the form of methane gas from consumed organic matter. The animal removes the methane building up in its rumen by repeated eructations of gas through its mouth and nostrils. Ruminant livestock are a notable source of atmospheric methane, with an estimated 17% of global enteric methane emissions from livestock. Historically, enteric methane was seen as an inefficiency in production and wasted dietary energy. This is still the case, but now methane is seen more as a pollutant and potent greenhouse gas. The gold standard method for measuring methane production from individual animals is a respiration chamber, which is used for metabolic studies. This approach to quantifying individual animal emissions has been used in research for over 100 years; however, it is not suitable for monitoring large numbers of animals in their natural environment on commercial farms. In recent years, several more mobile monitoring systems discussed here have been developed for direct measurement of enteric methane emissions from individual animals. Several factors (diet composition, rumen microbial community, and their relationship with morphology and physiology of the host animal) drive enteric methane production in ruminant populations. A reliable method for monitoring individual animal emissions in large populations would allow (1) genetic selection for low emitters, (2) benchmarking of farms, and (3) more accurate national inventory accounting

Chromosomal contacts connect loci associated with autism, BMI and head circumference phenotypes

Copy number variants (CNVs) are major contributors to genomic imbalance disorders. Phenotyping of 137 unrelated deletion and reciprocal duplication carriers of the distal 16p11.2 220 kb BP2-BP3 interval showed that these rearrangements are associated with autism spectrum disorders and mirror phenotypes of obesity/underweight and macrocephaly/microcephaly. Such phenotypes were previously associated with rearrangements of the non-overlapping proximal 16p11.2 600 kb BP4-BP5 interval. These two CNV-prone regions at 16p11.2 are reciprocally engaged in complex chromatin looping, as successfully confirmed by 4C-seq, fluorescence in situ hybridization and Hi-C, as well as coordinated expression and regulation of encompassed genes. We observed that genes differentially expressed in 16p11.2 BP4-BP5 CNV carriers are concomitantly modified in their chromatin interactions, suggesting that disruption of chromatin interplays could participate in the observed phenotypes. We also identified cis- and trans-acting chromatin contacts to other genomic regions previously associated with analogous phenotypes. For example, we uncovered that individuals with reciprocal rearrangements of the trans-contacted 2p15 locus similarly display mirror phenotypes on head circumference and weight. Our results indicate that chromosomal contacts’ maps could uncover functionally and clinically related genes.Molecular Psychiatry advance online publication, 31 May 2016; doi:10.1038/mp.2016.84

Targeted disruption of CD1d prevents NKT cell development in pigs

Studies in mice genetically lacking natural killer T (NKT) cells show that these lymphocytes make important contributions to both innate and adaptive immune responses. However, the usefulness of murine models to study human NKT cells is limited by the many differences between mice and humans, including that their NKT cell frequencies, subsets and distribution are dissimilar. A more suitable model may be swine that share many metabolic, physiological and growth characteristics with humans and are also similar for NKT cells. Thus, we analyzed genetically modified pigs made deficient for CD1d that is required for the development of Type I invariant NKT (iNKT) cells that express a semi-invariant T cell receptor (TCR) and Type II NKT cells that use variable TCRs. Peripheral blood analyzed by flow cytometry and interferon-γ (IFNγ) enzyme-linked immuno spot (ELISPOT) assays demonstrated that CD1d-knockout pigs completely lack iNKT cells while other leukocyte populations remain intact. CD1d and NKT cells have been shown to be involved in shaping the composition of the commensal microbiota in mice. Therefore, we also compared the fecal microbiota profile between pigs expressing and lacking NKT cells. However, no differences were found between pigs lacking or expressing CD1d. Our results are the first to show that knocking-out CD1d prevents the development of iNKT cells in a non-rodent species. CD1d-deficient pigs should offer a useful model to more accurately determine the contribution of NKT cells for human immune responses. They also have potential for understanding how NKT cells impact the health of commercial swine

Mental imagery and psychopathology: Examples of Post-Traumatic Stress Disorder and Bipolar Disorder

© 2013 Springer Science+Business Media, LLC. All rights reserved. This chapter aims to provide an update on the relation between mental imagery and psychopathology, with particular reference to post-traumatic stress disorder and bipolar affective disorder. Current evidence is provided to give an overview of the strengths and limitations of existing cognitive behavioural therapies for these two psychological disorders. Clinical vignettes are used to illustrate how imagery interventions may be incorporated into cognitive behavioural therapy to enrich the array of treatment strategies and possibly enhance its efficacy.status: publishe

Low-dose aspirin before spinal surgery: results of a survey among neurosurgeons in Germany

The main problem faced by the increasing numbers of patients presenting for spinal surgery are receiving concurrent medication with low-dose aspirin, leading to dysfunctional circulating platelets. The contribution of low-dose aspirin to increased peri-operative risk of bleeding and blood loss is a contentious issue with conflicting published results from different surgical groups. Data from neurosurgical spine patients is sparse, but aspirin has been identified as an important risk factor in the development of post-operative hematoma following intracranial surgery. We surveyed the opinions and working practices of the neurosurgical facilities performing spinal operations in Germany regarding patients who present for elective spinal surgery. Identical questionnaires were sent to 210 neurosurgical facilities and proffered five main questions: (1) the adherence of any policy of stopping aspirin pre-operatively, (2) the personal risk assessment for patients with spinal surgery under low-dose aspirin medication, (3) the preferred method of treatment for excessive bleeding in this context, (4) personal knowledge of hemorrhagic complications in this group of patients, and (5) the characteristics of the neurosurgical units concerned. There were 145 (69.1%) responses of which 142 (67.6%) were valid. Of the respondents, 114 (80.3%) had a (written) departmental policy for the discontinuation of pre-operative aspirin treatment, 28 (19.7%) were unaware of such a policy. The mean time suggested for discontinuation of aspirin pre-operatively was 6.9 days (range: 0–21 days), with seven respondents who perform the operations despite the ongoing aspirin medication. Ninety-four respondents (66.2%) considered that patients taking low-dose aspirin were at increased risk for excessive peri-operative hemorrhage or were indetermined (8.6%), and 73 (51.4%) reported having personal experience of such problems. Ninety-two respondents (65.5%) would use special medical therapy, preferably Desmopressin alone or in combination with other blood products or prohemostatic agents (46.1%), if hemorrhagic complications developed intra- or post-operatively. The average number of spinal operations per year in each service was 607.9 (range: 40–1,500). Despite the existence of distinct departmental policies concerning the discontinuation of low-dose aspirin pre-operatively in the majority of neurosurgical facilities performing spinal operations, there is a wide range of the moment of this interruption with an average of 7 days. Two-thirds of the respondents felt that aspirin was a risk factor for hemorrhagic complications associated with spinal procedures, and more than half of the interviewees reported having personal experience of such problems. Finally, various medicamentous methods of counteracting aspirin-induced platelet dysfunction and excessive bleeding in this context are elicited, discussed and evaluated