2,213 research outputs found
A Perspective of Preconception Health Activities in the United States
Objectives: Information regarding the type and scope of preconception care programs in the United States is scant. We evaluated State Title V measurement and indicator data and abstracts presented at the National Summit on Preconception Care (June 2005) in order to identify existing programs and innovative strategies for preconception health promotion. Methods: We used the web-based Title V Information System to identify state Performance Measures and Priority Needs pertaining to preconception health as reported for the 2005–2010 Needs Assessment Cycle. We also present a detailed summary of the abstracts presented at the National Summit on Preconception Care. Results: A total of 23 states reported a Priority Need that focused on preconception health and health care. Forty-two states and jurisdictions identified a Performance Measure associated with preconception health or a related indicator (e.g., folic acid, birth spacing, family planning, unintended pregnancy, and healthy weight). Nearly 60 abstracts pertaining to preconception care were presented at the National Summit and included topics such as research, programs, patient or provider toolkits, clinical practice strategies, and public policy. Conclusions: Strategies for improving preconception health have been incorporated into numerous programs throughout the United States. Widespread recognition of the benefits of preconception health promotion is evidenced by the number of states identifying related indicators
Contaminations contaminate common databases
The polymerase chain reaction (PCR) is a very powerful method to detect and identify pathogens. The high sensitivity of the method, however, comes with a cost; any of the millions of artificial DNA copies generated by PCR can serve as a template in a following experiment. If not identified as contaminations, these may result in erroneous conclusions on the occurrence of the pathogen, thereby inflating estimates of host range and geographic distribution. In the present paper, we evaluate whether several published records of avian haemosporidian parasites, in either unusual host species or geographical regions, might stem from PCR contaminations rather than novel biological findings. The detailed descriptions of these cases are shedding light upon the steps in the work process that might lead to PCR contaminations. By increasing the awareness of this problem, it will aid in developing procedures that keep these to a minimum. The examples in the present paper are from haemosporidians of birds, however the problem of contaminations and suggested actions should apply generally to all kinds of PCR‐based identifications, not just of parasites and pathogens
Sperm design and variation in the New World blackbirds (Icteridae)
Post-copulatory sexual selection (PCSS) is thought to be one of the evolutionary forces responsible for the rapid and divergent evolution of sperm design. However, whereas in some taxa particular sperm traits are positively associated with PCSS, in other taxa, these relationships are negative, and the causes of these different patterns across taxa are poorly understood. In a comparative study using New World blackbirds (Icteridae), we tested whether sperm design was influenced by the level of PCSS and found significant positive associations with the level of PCSS for all sperm components but head length. Additionally, whereas the absolute length of sperm components increased, their variation declined with the intensity of PCSS, indicating stabilizing selection around an optimal sperm design. Given the diversity of, and strong selection on, sperm design, it seems likely that sperm phenotype may influence sperm velocity within species. However, in contrast to other recent studies of passerine birds, but consistent with several other studies, we found no significant link between sperm design and velocity, using four different species that vary both in sperm design and PCSS. Potential reasons for this discrepancy between studies are discussed
Experimental realisation of Shor's quantum factoring algorithm using qubit recycling
Quantum computational algorithms exploit quantum mechanics to solve problems
exponentially faster than the best classical algorithms. Shor's quantum
algorithm for fast number factoring is a key example and the prime motivator in
the international effort to realise a quantum computer. However, due to the
substantial resource requirement, to date, there have been only four
small-scale demonstrations. Here we address this resource demand and
demonstrate a scalable version of Shor's algorithm in which the n qubit control
register is replaced by a single qubit that is recycled n times: the total
number of qubits is one third of that required in the standard protocol.
Encoding the work register in higher-dimensional states, we implement a
two-photon compiled algorithm to factor N=21. The algorithmic output is
distinguishable from noise, in contrast to previous demonstrations. These
results point to larger-scale implementations of Shor's algorithm by harnessing
scalable resource reductions applicable to all physical architectures.Comment: 7 pages, 3 figure
Biological control of broad mites (Polyphagotarsonemus latus) with the generalist predator Amblyseius swirskii
The broad mite is a serious pest of a variety of crops worldwide. Several phytoseiid mites have been described to control these mites. However, broad mites are still one of the major pest problems on greenhouse pepper in South-eastern Spain. The generalist predatory mite A. swirskii is widely used against other pests of pepper plants such as thrips and whiteflies, the latter being a vector of broad mites. We assessed the potential of A. swirskii to control broad mites. The oviposition rate of A. swirskii on a diet of broad mites was lower than on a diet of pollen, but higher than oviposition in the absence of food. Population-dynamical experiments with A. swirskii on single sweet pepper plants in a greenhouse compartment showed successful control of broad mites
Observation of Bose-Einstein Condensation in a Strong Synthetic Magnetic Field
Extensions of Berry's phase and the quantum Hall effect have led to the
discovery of new states of matter with topological properties. Traditionally,
this has been achieved using gauge fields created by magnetic fields or spin
orbit interactions which couple only to charged particles. For neutral
ultracold atoms, synthetic magnetic fields have been created which are strong
enough to realize the Harper-Hofstadter model. Despite many proposals and major
experimental efforts, so far it has not been possible to prepare the ground
state of this system. Here we report the observation of Bose-Einstein
condensation for the Harper-Hofstadter Hamiltonian with one-half flux quantum
per lattice unit cell. The diffraction pattern of the superfluid state directly
shows the momentum distribution on the wavefuction, which is gauge-dependent.
It reveals both the reduced symmetry of the vector potential and the twofold
degeneracy of the ground state. We explore an adiabatic many-body state
preparation protocol via the Mott insulating phase and observe the superfluid
ground state in a three-dimensional lattice with strong interactions.Comment: 6 pages, 5 figures. Supplement: 6 pages, 4 figure
Sperm competition-induced plasticity in the speed of spermatogenesis
Background: Sperm competition between rival ejaculates over the fertilization of ova typically selects for the production of large numbers of sperm. An obvious way to increase sperm production is to increase testis size, and most empirical work has focussed on this parameter. Adaptive plasticity in sperm production rate could also arise due to variation in the speed with which each spermatozoon is produced, but whether animals can respond to relevant environmental conditions by modulating the kinetics of spermatogenesis in this way has not been experimentally investigated. Results: Here we demonstrate that the simultaneously hermaphroditic flatworm Macrostomum lignano exhibits substantial plasticity in the speed of spermatogenesis, depending on the social context: worms raised under higher levels of sperm competition produce sperm faster. Conclusions: Our findings overturn the prevailing view that the speed of spermatogenesis is a static property of a genotype, and demonstrate the profound impact that social environmental conditions can exert upon a key developmental process. We thus identify, to our knowledge, a novel mechanism through which sperm production rate is maximised under sperm competition
Patterns in Age-Seroprevalence Consistent with Acquired Immunity against Trypanosoma brucei in Serengeti Lions
Trypanosomes cause disease in humans and livestock throughout sub-Saharan Africa. Although various species show evidence of clinical tolerance to trypanosomes, until now there has been no evidence of acquired immunity to natural infections. We discovered a distinct peak and decrease in age prevalence of T. brucei s.l. infection in wild African lions that is consistent with being driven by an exposure-dependent increase in cross-immunity following infections with the more genetically diverse species, T. congolense sensu latu. The causative agent of human sleeping sickness, T. brucei rhodesiense, disappears by 6 years of age apparently in response to cross-immunity from other trypanosomes, including the non-pathogenic subspecies, T. brucei brucei. These findings may suggest novel pathways for vaccinations against trypanosomiasis despite the notoriously complex antigenic surface proteins in these parasites
'To take care of the patients': Qualitative analysis of Veterans Health Administration personnel experiences with a clinical informatics system
<p>Abstract</p> <p>Background</p> <p>The Veterans Health Administration (VA) has invested significant resources in designing and implementing a comprehensive electronic health record (EHR) that supports clinical priorities. EHRs in general have been difficult to implement, with unclear cost-effectiveness. We describe VA clinical personnel interactions with and evaluations of the EHR.</p> <p>Methods</p> <p>As part of an evaluation of a quality improvement initiative, we interviewed 72 VA clinicians and managers using a semi-structured interview format. We conducted a qualitative analysis of interview transcripts, examining themes relating to participants' interactions with and evaluations of the VA EHR.</p> <p>Results</p> <p>Participants described their perceptions of the positive and negative effects of the EHR on their clinical workflow. Although they appreciated the speed and ease of documentation that the EHR afforded, they were concerned about the time cost of using the technology and the technology's potential for detracting from interpersonal interactions.</p> <p>Conclusions</p> <p>VA personnel value EHRs' contributions to supporting communication, education, and documentation. However, participants are concerned about EHRs' potential interference with other important aspects of healthcare, such as time for clinical care and interpersonal communication with patients and colleagues. We propose that initial implementation of an EHR is one step in an iterative process of ongoing quality improvement.</p
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