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1.
PLoS One ; 18(10): e0291874, 2023.
Article in English | MEDLINE | ID: mdl-37788253

ABSTRACT

Tens of millions of dried seahorses (genus Hippocampus) are traded annually, and the pressure from this trade along with their life history traits (involved parental care and small migration distances and home ranges) has led to near global population declines. This and other forms of overexploitation have led to all seahorse species being listed in Appendix II under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). The signatory nations of CITES recommended a 10-cm size limit of seahorses to ensure harvested individuals have reached reproductive maturity, and have thus had the chance to produce offspring, to maintain a more sustainable global seahorse fishery. We assessed adherence to CITES recommendations using DNA barcoding and size measurements to compare two prominent U.S. dried seahorse markets: (1) traditional Chinese medicine (TCM), and (2) non-medicinal ecommerce and coastal curio (ECC). We also estimated U.S. import abundance from CITES records. Of the nine species identified among all samples (n = 532), eight were found in the TCM trade (n = 168); composed mostly (75%) of the Indo-Pacific species Hippocampus trimaculatus, and Hippocampus spinosissimus, and the Latin American Hippocampus ingens. In contrast, ECC samples (n = 344) included 5 species, primarily juvenile Indo-Pacific Hippocampus kuda (51.5%) and the western Atlantic Hippocampus zosterae (40.7). The majority of TCM samples (85.7%) met the CITES size recommendation, in contrast to 4.8% of ECC samples. These results suggest non-size discriminatory bycatch is the most likely source of imported ECC specimens. In addition, CITES records indicate that approximately 602,275 dried specimens were imported into the U.S. from 2004-2020, but the exact species composition remains unknown as many U.S. imports records list one species or Hippocampus spp. from confiscated shipments due to difficulties in morphological identification and large numbers of individuals per shipment. Molecular identification was used to identify the species composition of confiscated shipment imports containing undesignated species, and similar to TCM, found H. trimaculatus and H. spinosissimus the most abundant. By combining DNA barcoding, size comparisons, and CITES database records, these results provide an important glimpse into the two primary dried U.S. seahorse end-markets, and may further inform the conservation status of several Hippocampus species.


Subject(s)
Smegmamorpha , Humans , Animals , Smegmamorpha/genetics , Medicine, Chinese Traditional , Commerce , Internationality , Endangered Species
3.
Proc Biol Sci ; 287(1926): 20200657, 2020 05 13.
Article in English | MEDLINE | ID: mdl-32370669

ABSTRACT

Ocean circulation driving macro-algal rafting is believed to serve as an important mode of dispersal for many marine organisms, leading to predictions on population-level genetic connectivity and the directionality of effective dispersal. Here, we use genome-wide single nucleotide polymorphism data to investigate whether gene flow directionality in two seahorses (Hippocampus) and three pipefishes (Syngnathus) follows the predominant ocean circulation patterns in the Gulf of Mexico and northwestern Atlantic. In addition, we explore whether gene flow magnitudes are predicted by traits related to active dispersal ability and habitat preference. We inferred demographic histories of these co-distributed syngnathid species, and coalescent model-based estimates indicate that gene flow directionality is in agreement with ocean circulation data that predicts eastward and northward macro-algal transport. However, the magnitude to which ocean currents influence this pattern appears strongly dependent on the species-specific traits related to rafting propensity and habitat preferences. Higher levels of gene flow and stronger directionality are observed in Hippocampus erectus, Syngnathus floridae and Syngnathus louisianae, which closely associated with the pelagic macro-algae Sargassum spp., compared to Hippocampus zosterae and the Syngnathus scovelli/Syngnathus fuscus sister-species pair, which prefer near shore habitats and are weakly associated with pelagic Sargassum. This study highlights how the combination of population genomic inference together with ocean circulation data can help explain patterns of population structure and diversity in marine ecosystems.


Subject(s)
Gene Flow , Smegmamorpha/genetics , Animals , Ecosystem , Genetics, Population
4.
Reprod Biomed Soc Online ; 6: 72-79, 2018 Aug.
Article in English | MEDLINE | ID: mdl-30519650

ABSTRACT

This study examined the attitudes of obstetrics and gynaecology (OB/GYN) resident physicians to initiating patient discussions regarding medical and elective oocyte cryopreservation (OC). The study used a cross-sectional online survey of OB/GYN medical residents in the USA, sampled from residency programmes approved by the American Council for Graduate Medical Education. In total, 208 medical residents, distributed evenly between postgraduate years 1-4, participated in the study. Residents' fertility knowledge and attitudes to initiating discussions about OC were gathered. Forty percent (n = 83) believed that OB/GYN residents should initiate discussions about OC with patients (initiators), while 60% (n = 125) did not (non-initiators). Initiators were less likely to overestimate the age at which a woman's fertility begins to decline, and were more likely to believe that discussions about OC and age-related fertility decline should take place during a well-woman annual examination. Initiators and non-initiators did not differ in their attitudes towards discussing OC with patients undergoing cancer treatments; however, initiators were significantly more likely to discuss elective OC with patients who were currently unpartnered or who wished to delay childbearing to pursue a career. Given the increasing age of childbearing among women, and the fact that women prefer to receive reproductive information from their healthcare providers, it is critical that such topics are discussed in consultations to assist patients in making more informed reproductive decisions. Further research is needed to assess the existing barriers to these discussions from both physician and patient perspectives.

5.
Hum Reprod ; 31(2): 403-11, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26677956

ABSTRACT

STUDY QUESTION: What knowledge, attitudes and intentions do US obstetrics and gynecology (OB/GYN) residents have toward discussing age-related fertility decline and oocyte cryopreservation with their patients? SUMMARY ANSWER: Most OB/GYN residents believe that age-related fertility decline, but not oocyte cryopreservation, should be discussed during well-woman annual exams; furthermore, nearly half of residents overestimated the age at which female fertility markedly declines. WHAT IS KNOWN ALREADY: Oocyte cryopreservation can be utilized to preserve fertility potential. Currently, no studies of US OB/GYN residents exist that question their knowledge, attitudes, and intentions toward discussing age-related fertility decline and oocyte cryopreservation with patients. STUDY DESIGN, SIZE, DURATION: A cross-sectional online survey was conducted during the fall of 2014 among residents in American Council for Graduate (ACOG) Medical Education-approved OB/GYN residency programs. Program directors were emailed via the ACOG Council on Resident Education in Obstetrics and Gynecology server listing and asked to solicit resident participation. PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants included 238 residents evenly distributed between post-graduate years 1-4 with varied post-residency plans; 90% of residents were women and 75% were 26-30 years old. The survey was divided into three sections: demographics, fertility awareness, and attitudes toward discussing fertility preservation options with patients. Descriptive and inferential statistics were conducted. MAIN RESULTS AND THE ROLE OF CHANCE: A strong majority of residents (83%) believed an OB/GYN should initiate discussions about age-related fertility decline with patients (mean patient age 31.8), and 73% percent believed these discussions should be part of an annual exam. One third of residents overestimated the age at which there is a slight decline in female fertility, while nearly half of residents overestimated the age at which female fertility markedly declines. Over three-quarters of residents (78.4%) also overestimated the likelihood of success using assisted reproductive treatments (ARTs). Residents were likely to support oocyte cryopreservation in cancer patients irrespective of the woman's age, but much less likely to support elective oocyte cryopreservation. For elective oocyte cryopreservation, 40% believed OB/GYNs should initiate discussions with patients (mean age 31.1), while only 20% believed this topic should be part of an annual exam. LIMITATIONS, REASONS FOR CAUTION: Because the study invitation was sent through US OB/GYN residency program directors rather than directly to residents, it is possible that some residents did not receive the invitation to participate. This limits the generalizability of the findings. WIDER IMPLICATIONS OF THE FINDINGS: Within the USA, there appears to be a critical need for improved education on fertility decline in OB/GYN residency programs. To promote informed reproductive decision-making among patients, efforts should be made to help OB/GYNs provide comprehensive fertility education to all women, while also respecting patient choices. STUDY FUNDING/COMPETING INTERESTS: None.


Subject(s)
Attitude of Health Personnel , Cryopreservation , Infertility, Female/psychology , Internship and Residency , Oocytes , Physicians/psychology , Adult , Cross-Sectional Studies , Female , Fertility Preservation/psychology , Gynecology/education , Humans , Intention , Obstetrics/education , United States
6.
PLoS One ; 10(7): e0132308, 2015.
Article in English | MEDLINE | ID: mdl-26200110

ABSTRACT

The dwarf seahorse (Hippocampus zosterae) is widely distributed throughout near-shore habitats of the Gulf of Mexico and is of commercial significance in Florida, where it is harvested for the aquarium and curio trades. Despite its regional importance, the genetic structure of dwarf seahorse populations remains largely unknown. As an aid to ongoing conservation efforts, we employed three commonly applied mtDNA markers (ND4, DLoop and CO1) to investigate the genetic structuring of H. zosterae in Florida using samples collected throughout its range in the state. A total of 1450 bp provided sufficient resolution to delineate four populations of dwarf seahorses, as indicated by significant fixation indices. Despite an overall significant population structure, we observed evidence of interbreeding between individuals from geographically distant sites, supporting the hypothesis that rafting serves to maintain a degree of population connectivity. All individuals collected from Pensacola belong to a single distinct subpopulation, which is highly differentiated from the rest of Floridian dwarf seahorses sampled. Our findings highlight the utility of mtDNA markers in evaluating barriers to gene flow and identifying genetically distinct populations, which are vital to the development of comprehensive conservation strategies for exploited taxa.


Subject(s)
DNA, Mitochondrial/analysis , Sequence Analysis, DNA/methods , Smegmamorpha/classification , Smegmamorpha/genetics , Animals , Breeding , Conservation of Natural Resources/methods , Florida , Gene Flow , Genetics, Population , Humans , Molecular Sequence Data , Phylogeography
7.
PLoS One ; 10(1): e0116219, 2015.
Article in English | MEDLINE | ID: mdl-25629166

ABSTRACT

Understanding population structure and areas of demographic persistence and transients is critical for effective species management. However, direct observational evidence to address the geographic scale and delineation of ephemeral or persistent populations for many marine fishes is limited. The Lined seahorse (Hippocampus erectus) can be commonly found in three western Atlantic zoogeographic provinces, though inhabitants of the temperate northern Virginia Province are often considered tropical vagrants that only arrive during warm seasons from the southern provinces and perish as temperatures decline. Although genetics can locate regions of historical population persistence and isolation, previous evidence of Virginia Province persistence is only provisional due to limited genetic sampling (i.e., mitochondrial DNA and five nuclear loci). To test alternative hypotheses of historical persistence versus the ephemerality of a northern Virginia Province population we used a RADseq generated dataset consisting of 11,708 single nucleotide polymorphisms (SNP) sampled from individuals collected from the eastern Gulf of Mexico to Long Island, NY. Concordant results from genomic analyses all infer three genetically divergent subpopulations, and strongly support Virginia Province inhabitants as a genetically diverged and a historically persistent ancestral gene pool. These results suggest that individuals that emerge in coastal areas during the warm season can be considered "local" and supports offshore migration during the colder months. This research demonstrates how a large number of genes sampled across a geographical range can capture the diversity of coalescent histories (across loci) while inferring population history. Moreover, these results clearly demonstrate the utility of population genomic data to infer peripheral subpopulation persistence in difficult-to-observe species.


Subject(s)
Genetics, Population , Genomics , Smegmamorpha/genetics , Animal Migration , Animals , Atlantic Ocean , Biodiversity , Ecosystem , Evolution, Molecular , Genetic Variation , Oceanography , Seasons
8.
Oncogene ; 34(16): 2061-71, 2015 Apr 16.
Article in English | MEDLINE | ID: mdl-24909179

ABSTRACT

Targeting HER2 with antibodies or small molecule inhibitors in HER2-positive breast cancer leads to improved survival, but resistance is a common clinical problem. To uncover novel mechanisms of resistance to anti-HER2 therapy in breast cancer, we performed a kinase open reading frame screen to identify genes that rescue HER2-amplified breast cancer cells from HER2 inhibition or suppression. In addition to multiple members of the MAPK (mitogen-activated protein kinase) and PI3K (phosphoinositide 3-kinase) signaling pathways, we discovered that expression of the survival kinases PRKACA and PIM1 rescued cells from anti-HER2 therapy. Furthermore, we observed elevated PRKACA expression in trastuzumab-resistant breast cancer samples, indicating that this pathway is activated in breast cancers that are clinically resistant to trastuzumab-containing therapy. We found that neither PRKACA nor PIM1 restored MAPK or PI3K activation after lapatinib or trastuzumab treatment, but rather inactivated the pro-apoptotic protein BAD, the BCl-2-associated death promoter, thereby permitting survival signaling through BCL-XL. Pharmacological blockade of BCL-XL/BCL-2 partially abrogated the rescue effects conferred by PRKACA and PIM1, and sensitized cells to lapatinib treatment. These observations suggest that combined targeting of HER2 and the BCL-XL/BCL-2 anti-apoptotic pathway may increase responses to anti-HER2 therapy in breast cancer and decrease the emergence of resistant disease.


Subject(s)
Antibodies, Monoclonal, Humanized/therapeutic use , Antineoplastic Agents/therapeutic use , Breast Neoplasms/drug therapy , Cyclic AMP-Dependent Protein Kinase Catalytic Subunits/physiology , Drug Resistance, Neoplasm/genetics , Protein Kinase Inhibitors/therapeutic use , Quinazolines/therapeutic use , Receptor, ErbB-2/antagonists & inhibitors , Apoptosis/drug effects , Cyclic AMP-Dependent Protein Kinase Catalytic Subunits/genetics , Female , Gene Expression Profiling , HEK293 Cells , Humans , Lapatinib , Mitogen-Activated Protein Kinases/genetics , Open Reading Frames/genetics , Phosphatidylinositol 3-Kinases/genetics , Phosphorylation , Proto-Oncogene Proteins c-pim-1/genetics , Trastuzumab , bcl-Associated Death Protein/antagonists & inhibitors , bcl-Associated Death Protein/metabolism , bcl-X Protein/antagonists & inhibitors
9.
Ultraschall Med ; 35(5): 459-67, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24764211

ABSTRACT

PURPOSE: The aim of this study was to assess different aspects of reliability in high-resolution ultrasonography (HRUS) of the peripheral nerves and to establish reference values for the most frequently examined nerve segments. MATERIALS AND METHODS: A nerve size parameter, the cross-sectional area (CSA) of the C5, C6 and C7 cervical roots, the median, ulnar, radial, superficial radial, peroneal, tibial, and the sural nerves was measured using HRUS at a total of 14 predefined anatomical sites in two different cohorts of healthy subjects (n = 56), and the inter-rater, intra-rater and inter-equipment reliability of measurements was assessed. RESULTS: The mean CSA of the 14 nerve segments ranged from 2 to 10 mm(2). The intra-rater, inter-rater and inter-equipment reliability was high with intraclass correlation coefficients of 0.93, 0.98, and 0.86, respectively. The CSA values showed no consistent correlation with age, height, and body weight, but males had significantly larger values than females for nerve segments on the arm after correcting for age, weight and height in multivariate analysis. CSA values did not differ when two independent cohorts were compared. CONCLUSION: Peripheral nerve ultrasonography is a reliable and reproducible diagnostic method in the hands of experienced examiners. Normal values for several upper and lower extremity nerves are provided by our study.


Subject(s)
Image Enhancement/methods , Peripheral Nerves/diagnostic imaging , Adult , Cohort Studies , Female , Humans , Male , Middle Aged , Observer Variation , Reference Values , Reproducibility of Results , Ultrasonography
10.
J Comp Pathol ; 148(4): 365-72, 2013 May.
Article in English | MEDLINE | ID: mdl-23083834

ABSTRACT

In order to determine the diversity and pathogenicity of Erysipelothrix spp. isolates recovered from marine fish, a harbour seal (Phoca vitulina) and the marine environment, 14 isolates were characterized by genotyping, serotyping, determination of the surface protective antigen (spa) gene type and assessment of virulence in a pig bioassay. All 14 isolates were Erysipelothrix rhusiopathiae. Isolates were determined to be of serotypes 2 (n = 3), 3 (n = 1), 4 (n = 1), 12 (n = 1), 15 (n = 1) or 21 (n = 6), and one isolate cross-reacted with serotypes 5 and 21. The spa gene analysis determined that 64.3% (n = 9) were spaA and 35.7% (n = 5) were spaB1. In pigs, 10/14 isolates induced small plaques to diamond-shaped cutaneous lesions consistent with Erysipelothrix spp. infection. The results of this study indicate that the marine E. rhusiopathiae isolates have greater genetic and antigenic diversity than pig isolates and are capable of inducing classical skin lesions in pigs.


Subject(s)
Erysipelothrix Infections/transmission , Erysipelothrix/pathogenicity , Fishes , Phoca , Skin Diseases/veterinary , Skin/pathology , Swine Diseases/transmission , Animals , Erysipelothrix/genetics , Erysipelothrix/isolation & purification , Erysipelothrix Infections/immunology , Erysipelothrix Infections/pathology , Serotyping , Skin/immunology , Skin Diseases/immunology , Skin Diseases/pathology , Swine , Swine Diseases/immunology , Swine Diseases/pathology
11.
J Comp Physiol B ; 182(2): 299-309, 2012 Feb.
Article in English | MEDLINE | ID: mdl-21935721

ABSTRACT

Odontocetes have an exceptional range in body mass spanning 10(3) kg across species. Because, size influences oxygen utilization and carbon dioxide production rates in mammals, this lineage likely displays an extraordinary variation in oxygen store management compared to other marine mammal groups. To examine this, we measured changes in the partial pressures of respiratory gases ([Formula: see text], [Formula: see text]), pH, and lactate in the blood during voluntary, quiescent, submerged breath holds in Pacific white-sided dolphins (Lagenorhynchus obliquidens), bottlenose dolphins (Tursiops truncatus), and a killer whale (Orcinus orca) representing a mass range of 96-3,850 kg. These measurements provided an empirical determination of the effect of body size on the variability in blood biochemistry during breath hold and experimentally determined aerobic dive limits (ADL) within one taxonomic group (odontocetes). For the species in this study, maximum voluntary breath-hold duration was positively correlated with body mass, ranging from 3.5 min in white-sided dolphins to 13.3 min for the killer whale. Variation in breath-hold duration was associated with differences in the rate of change for [Formula: see text] throughout breath hold; [Formula: see text] decreased twice as fast for the two smaller species (-0.6 mmHg O(2) min(-1)) compared to the largest species (-0.3 mmHg O(2) min(-1)). In contrast, the rate of increase in [Formula: see text] during breath hold was similar across species. These results demonstrate that large body size in odontocetes facilitates increased aerobic breath-hold capacity as mediated by decreased mass-specific metabolic rates (rates of change in [Formula: see text] served as a proxy for oxygen utilization). Indeed the experimentally determined 5 min ADL for bottlenose dolphins was surpassed by the 13.3 min maximum breath hold of the killer whale, which did not end in a rise in lactate. Rather, breath hold ended voluntarily as respiratory gases and pH fell within a narrow range for both large and small species, likely providing cues for ventilation.


Subject(s)
Body Size/physiology , Carbon Dioxide/analysis , Dolphins/physiology , Oxygen/analysis , Respiration , Animals , Breath Tests , Dolphins/metabolism , Female , Hydrogen-Ion Concentration , Lactic Acid/blood , Male , Partial Pressure , Species Specificity
12.
Oncogene ; 31(29): 3397-408, 2012 Jul 19.
Article in English | MEDLINE | ID: mdl-22105362

ABSTRACT

Activating mutations in the RAS family or BRAF frequently occur in many types of human cancers but are rarely detected in breast tumors. However, activation of the RAS-RAF-MEK-ERK MAPK pathway is commonly observed in human breast cancers, suggesting that other genetic alterations lead to activation of this signaling pathway. To identify breast cancer oncogenes that activate the MAPK pathway, we screened a library of human kinases for their ability to induce anchorage-independent growth in a derivative of immortalized human mammary epithelial cells (HMLE). We identified p21-activated kinase 1 (PAK1) as a kinase that permitted HMLE cells to form anchorage-independent colonies. PAK1 is amplified in several human cancer types, including 30--33% of breast tumor samples and cancer cell lines. The kinase activity of PAK1 is necessary for PAK1-induced transformation. Moreover, we show that PAK1 simultaneously activates MAPK and MET signaling; the latter via inhibition of merlin. Disruption of these activities inhibits PAK1-driven anchorage-independent growth. These observations establish PAK1 amplification as an alternative mechanism for MAPK activation in human breast cancer and credential PAK1 as a breast cancer oncogene that coordinately regulates multiple signaling pathways, the cooperation of which leads to malignant transformation.


Subject(s)
Breast Neoplasms/pathology , MAP Kinase Signaling System/genetics , Mitogen-Activated Protein Kinases/metabolism , Oncogenes , Proto-Oncogene Proteins c-met/metabolism , p21-Activated Kinases/genetics , p21-Activated Kinases/metabolism , Breast Neoplasms/enzymology , Breast Neoplasms/genetics , Breast Neoplasms/metabolism , Cell Proliferation , Cell Transformation, Neoplastic/genetics , Enzyme Activation/genetics , Genome, Human/genetics , Humans , Mammary Glands, Human/cytology , Mammary Glands, Human/metabolism , Mammary Glands, Human/pathology , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism
13.
Biosens Bioelectron ; 26(7): 3154-9, 2011 Mar 15.
Article in English | MEDLINE | ID: mdl-21255994

ABSTRACT

Sensors based on surface plasmon resonance (SPR) allow rapid, label-free, highly sensitive detection, and indeed this phenomenon underpins the only label-free optical biosensing technology that is available commercially. In these sensors, the existence of surface plasmons is inferred indirectly from absorption features that correspond to the coupling of light into a thin metallic film. Although SPR is not intrinsically a radiative process, when the metallic coating which support the plasmonic wave exhibits a significant surface roughness, the surface plasmon can itself couple to the local photon states, and emit light. Here we show that using silver coated optical fibres, this novel SPR transducing mechanism offers significant advantages compare to traditional reflectance based measurements such as lower dependency on the metallic thickness and higher signal to noise ratio. Furthermore, we show that more complex sensor architectures with multiple sensing regions scattered along a single optical fibre enable multiplexed detection and dynamic self referencing of the sensing signal. Moreover, this alternative approach allows to combine two different sensing technologies, SPR and fluorescence sensing within the same device, which has never been demonstrated previously. As a preliminary proof of concept of potential application, this approach has been used to demonstrate the detection of the seasonal influenza A virus.


Subject(s)
Influenza A virus/isolation & purification , Influenza, Human/diagnosis , Optical Fibers , Silver/chemistry , Surface Plasmon Resonance/instrumentation , Equipment Design , Humans , Sensitivity and Specificity , Surface Plasmon Resonance/economics , Time Factors
14.
Am J Med Genet A ; 152A(3): 741-7, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20186778

ABSTRACT

Vici syndrome is a rare, genetically unresolved congenital multisystem disorder comprising agenesis of the corpus callosum, cataracts, immunodeficiency, cardiomyopathy, and hypopigmentation. An associated neuromuscular phenotype has not previously been described in detail. We report on an infant with clinical features suggestive of Vici syndrome and additional sensorineural hearing loss. Muscle biopsy revealed several changes including markedly increased variability in fiber size, increased internal nuclei, and abnormalities on Gomori trichrome and oxidative stains, raising a wide differential diagnosis including neurogenic atrophy, centronuclear myopathy (CNM) or a metabolic (mitochondrial) cytopathy. Respiratory chain enzyme studies, however, were normal and sequencing of common CNM-associated genes did not reveal any mutations. This case expands the clinical spectrum of Vici syndrome and indicates that muscle biopsy ought to be considered in infants presenting with suggestive clinical features. In addition, we suggest that Vici syndrome is considered in the differential diagnosis of infants presenting with congenital callosal agenesis and that additional investigation has to address the possibility of associated ocular, auditory, cardiac, and immunologic involvement when this radiologic finding is present.


Subject(s)
Abnormalities, Multiple/genetics , Acrocallosal Syndrome/genetics , Hearing Loss, Sensorineural/genetics , Muscle, Skeletal/pathology , Cataract/genetics , Humans , Hypopigmentation/genetics , Infant , Male , Muscle, Skeletal/innervation , Syndrome
15.
Phys Rev Lett ; 103(26): 261802, 2009 Dec 31.
Article in English | MEDLINE | ID: mdl-20366304

ABSTRACT

This Letter reports on a search for nu(mu) --> nu(e) transitions by the MINOS experiment based on a 3.14x10(20) protons-on-target exposure in the Fermilab NuMI beam. We observe 35 events in the Far Detector with a background of 27+/-5(stat)+/-2(syst) events predicted by the measurements in the Near Detector. If interpreted in terms of nu(mu) --> nu(e) oscillations, this 1.5sigma excess of events is consistent with sin2(2theta(13)) comparable to the CHOOZ limit when |Delta m2|=2.43x10(-3) eV2 and sin2(2theta(23))=1.0 are assumed.

16.
Phys Rev Lett ; 101(22): 221804, 2008 Nov 28.
Article in English | MEDLINE | ID: mdl-19113477

ABSTRACT

We report the first detailed comparisons of the rates and spectra of neutral-current neutrino interactions at two widely separated locations. A depletion in the rate at the far site would indicate mixing between nu(mu) and a sterile particle. No anomalous depletion in the reconstructed energy spectrum is observed. Assuming oscillations occur at a single mass-squared splitting, a fit to the neutral- and charged-current energy spectra limits the fraction of nu(mu) oscillating to a sterile neutrino to be below 0.68 at 90% confidence level. A less stringent limit due to a possible contribution to the measured neutral-current event rate at the far site from nu(e) appearance at the current experimental limit is also presented.

17.
Phys Rev Lett ; 101(15): 151601, 2008 Oct 10.
Article in English | MEDLINE | ID: mdl-18999585

ABSTRACT

A search for a sidereal modulation in the MINOS near detector neutrino data was performed. If present, this signature could be a consequence of Lorentz and CPT violation as predicted by the effective field theory called the standard-model extension. No evidence for a sidereal signal in the data set was found, implying that there is no significant change in neutrino propagation that depends on the direction of the neutrino beam in a sun-centered inertial frame. Upper limits on the magnitudes of the Lorentz and CPT violating terms in the standard-model extension lie between 10(-4) and 10(-2) of the maximum expected, assuming a suppression of these signatures by a factor of 10(-17).

18.
Phys Rev Lett ; 101(13): 131802, 2008 Sep 26.
Article in English | MEDLINE | ID: mdl-18851439

ABSTRACT

This Letter reports new results from the MINOS experiment based on a two-year exposure to muon neutrinos from the Fermilab NuMI beam. Our data are consistent with quantum-mechanical oscillations of neutrino flavor with mass splitting |Deltam2| = (2.43+/-0.13) x 10(-3) eV2 (68% C.L.) and mixing angle sin2(2theta) > 0.90 (90% C.L.). Our data disfavor two alternative explanations for the disappearance of neutrinos in flight: namely, neutrino decays into lighter particles and quantum decoherence of neutrinos, at the 3.7 and 5.7 standard-deviation levels, respectively.

19.
J Clin Pathol ; 61(2): 225-32, 2008 Feb.
Article in English | MEDLINE | ID: mdl-17496188

ABSTRACT

BACKGROUND: Although a large number of pathology-specific websites (PSWs) are accessible on the internet, the potential use of PSWs is relatively unknown among pathologists. As a PSW-directory does not exist, it may be difficult to find certain resources that are scattered over the internet. AIMS: To critically revisit PSWs in order to create a collection of selected websites that may be useful for practising pathologists worldwide. METHODS: Using special medical databases and link collections, extensive search for PSWs was performed on the world wide web. Each website was evaluated with regard to content and practical use for pathologists. RESULTS: PSWs contain electronic training manuals, journals, case collections, photo-archives, link directories, or slide collections of virtual microscopy. PSWs offer lavishly illustrated education material for undergraduates and postgraduates in pathology, but may also be very useful as reference books or as an instrument of continuing medical education for experienced pathologists. The paper shows how to find PSWs, and presents an annotated list of 100 of the best PSWs. CONCLUSIONS: PSWs as a whole form a heterogeneous patchwork of information. It is suggested that a central catalogue listing all PSWs that are available worldwide be established. This database would enable pathologists to have immediate access to all up-to-date pathology-specific resources on the internet, without the need to perform any laborious web research for themselves. It is hoped that in the future, the repertoire of on-line resources in pathology will be systematically perfected. The internet will then play a central role in the daily practice of pathologists as a medium of information and communication.


Subject(s)
Information Services , Internet , Pathology , Databases, Factual , Education, Medical/methods , Pathology/education
20.
Phys Rev Lett ; 97(19): 191801, 2006 Nov 10.
Article in English | MEDLINE | ID: mdl-17155614

ABSTRACT

This Letter reports results from the MINOS experiment based on its initial exposure to neutrinos from the Fermilab NuMI beam. The rates and energy spectra of charged current nu(mu) interactions are compared in two detectors located along the beam axis at distances of 1 and 735 km. With 1.27 x 10(20) 120 GeV protons incident on the NuMI target, 215 events with energies below 30 GeV are observed at the Far Detector, compared to an expectation of 336+/-14 events. The data are consistent with nu(mu) disappearance via oscillations with |Delta(m)2/32|=2.74 +0.44/-0.26 x10(-3)eV(2) and sin(2)(2theta(23))>0.87 (68% C.L.).

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