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1.
Opt Express ; 31(25): 41326-41338, 2023 Dec 04.
Article in English | MEDLINE | ID: mdl-38087534

ABSTRACT

We demonstrate laser frequency stabilization with at least 6 GHz of offset tunability using an in-phase/quadrature (IQ) modulator to generate electronic sidebands (ESB) on a titanium sapphire laser at 714 nm and we apply this technique to perform isotope shift spectroscopy of 226Ra and 225Ra. By locking the laser to a single resonance of a high finesse optical cavity and adjusting the lock offset, we determine the frequency difference between the magneto-optical trap (MOT) transitions in the two isotopes to be 2630.0 ± 0.3 MHz, a factor of 29 more precise than the previously available data. Using the known value of the hyperfine splitting of the 3P1 level, we calculate the isotope shift for the 1S0 to 3P1 transition to be 2267.0 ± 2.2 MHz, a factor of 8 more precise than the best available value. Our technique could be applied to countless other atomic systems to provide unprecedented precision in isotope shift spectroscopy and other relative frequency comparisons.

2.
Phys Rev Lett ; 129(18): 182502, 2022 Oct 28.
Article in English | MEDLINE | ID: mdl-36374704

ABSTRACT

We report the first precise measurement of a ß-recoil correlation from a radioactive noble gas (^{6}He) confined via a magneto-optical trap. The measurement is motivated by the search for exotic tensor-type contributions to the charged weak current. Interpreted as tensor currents with right-handed neutrinos, the measurements yield |C_{T}/C_{A}|^{2}≤0.022 (90% confidence limit, C.L.). On the other hand, for left-handed neutrinos the limits are 0.007

3.
Rev Sci Instrum ; 88(5): 055105, 2017 May.
Article in English | MEDLINE | ID: mdl-28571399

ABSTRACT

A method for alignment of a vector magnetometer to a rigidly attached prism is presented. This enables optical comparison of the magnetometer axes to physical surfaces in the apparatus, and thus an absolute determination of the magnetic field direction in space. This is in contrast with more common techniques, which focus on precise determination of the relative angles between magnetometer axes, and so are more suited to measuring differences in the direction of magnetic fields. Here we demonstrate precision better than 500 µrad on a fluxgate magnetometer, which also gives the coil orthogonality errors to a similar precision. The relative sensitivity of the three axes is also determined, with a precision of about 5 × 10-4.

4.
Occup Med (Lond) ; 66(4): 268-275, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27162253

ABSTRACT

BACKGROUND: Occupational colour vision testing is a requirement in a number of transport industries, and there are a number of tests that are considered acceptable by the various industry regulatory bodies. AIMS: To review the occupational colour vision tests currently in use nationally and internationally and determine whether they give consistent results. METHODS: A systematic review of the evidence was carried out according to standard methods. The Ovid Medline database was searched from 1946 to March 2013 using a broad and inclusive strategy. RESULTS: A total of 8951 citations were identified, from which 20 papers were selected for data analysis. Of these papers, 13 of 20 assessed test sensitivity and specificity, and 11 papers measured the number, type and severity of colour vision deficiency of subjects passing the tests. Three studies also measured test repeatability. The quality of studies included was generally good. Sensitivity and specificity ranged from 64% to 100% and 88% to 100%, respectively. The studies evaluating the newer screen-based tests reported the highest sensitivity and specificity. The marked variability reported between tests and within tests can be attributed to many factors including test protocol, sample selection, test distance and time for dark adaptation. CONCLUSIONS: There was low consistency between the colour vision tests examined. Lantern tests cannot be used to identify type or severity of colour vision deficit and, when used as a screening test for 'colour safe' status, give variable results. These results highlight the need for standardization across the transport industries.


Subject(s)
Color Vision Defects/diagnosis , Color Vision , Humans , Occupational Health Services/methods , Sensitivity and Specificity
5.
J R Army Med Corps ; 162(6): 434-439, 2016 Dec.
Article in English | MEDLINE | ID: mdl-26036822

ABSTRACT

BACKGROUND: Heat illness is a preventable disorder in military populations. Measures that protect vulnerable individuals and contribute to effective Immediate Treatment may reduce the impact of heat illness, but depend upon adequate understanding and awareness among Commanders and their troops. OBJECTIVE: To assess risk factors for heat illness in British soldiers deployed to the hot Collective Training Environment (CTE) and to explore awareness of Immediate Treatment responses. METHODS: An anonymous questionnaire was distributed to British soldiers deployed in the hot CTEs of Kenya and Canada. Responses were analysed to determine the prevalence of individual (Intrinsic) and Command-practice (Extrinsic) risk factors for heat illness and the self-reported awareness of key Immediate Treatment priorities (recognition, first aid and casualty evacuation). RESULTS: The prevalence of Intrinsic risk factors was relatively low in comparison with Extrinsic risk factors. The majority of respondents were aware of key Immediate Treatment responses. The most frequently reported factors in each domain were increased risk by body composition scoring, inadequate time for heat acclimatisation and insufficient briefing about casualty evacuation. CONCLUSIONS: Novel data on the distribution and scale of risk factors for heat illness are presented. A collective approach to risk reduction by the accumulation of 'marginal gains' is proposed for the UK military. This should focus on limiting Intrinsic risk factors before deployment, reducing Extrinsic factors during training and promoting timely Immediate Treatment responses within the hot CTE.


Subject(s)
Acclimatization , Body Composition , Heat Stress Disorders/epidemiology , Military Personnel , Physical Fitness , Adrenergic beta-Antagonists/therapeutic use , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Canada/epidemiology , Dehydration/epidemiology , Histamine Antagonists/therapeutic use , Humans , Hunger , Kenya/epidemiology , Prevalence , Risk Factors , Sleep Deprivation/epidemiology , Surveys and Questionnaires , United Kingdom/epidemiology
6.
Phys Rev Lett ; 114(23): 233002, 2015 Jun 12.
Article in English | MEDLINE | ID: mdl-26196797

ABSTRACT

The radioactive radium-225 ((225)Ra) atom is a favorable case to search for a permanent electric dipole moment. Because of its strong nuclear octupole deformation and large atomic mass, (225)Ra is particularly sensitive to interactions in the nuclear medium that violate both time-reversal symmetry and parity. We have developed a cold-atom technique to study the spin precession of (225)Ra atoms held in an optical dipole trap, and demonstrated the principle of this method by completing the first measurement of its atomic electric dipole moment, reaching an upper limit of |d((225)Ra)|<5.0×10(-22) e cm (95% confidence).

7.
Phys Rev Lett ; 113(3): 033003, 2014 Jul 18.
Article in English | MEDLINE | ID: mdl-25083643

ABSTRACT

We report the first experimental determination of the hyperfine quenching rate of the 6s(2) (1)S(0)(F = 1/2) - 6s6p (3)P(0)(F = 1/2) transition in (171)Yb with nuclear spin I = 1/2. This rate determines the natural linewidth and the Rabi frequency of the clock transition of a Yb optical frequency standard. Our technique involves spectrally resolved fluorescence decay measurements of the lowest lying (3)P(0,1) levels of neutral Yb atoms embedded in a solid Ne matrix. The solid Ne provides a simple way to trap a large number of atoms as well as an efficient mechanism for populating (3)P(0). The decay rates in solid Ne are modified by medium effects including the index-of-refraction dependence. We find the (3)P(0) hyperfine quenching rate to be (4.42 ± 0.35) × 10(-2) s(-1) for free (171)Yb, which agrees with recent ab initio calculations.

8.
J R Army Med Corps ; 158(3): 229-31, 2012 Sep.
Article in English | MEDLINE | ID: mdl-23472572

ABSTRACT

Species of the Opuntia or prickly pear genus of cacti are endemic to the British Army Training Unit Suffield (BATUS) training area in Alberta, Canada. They are known to provoke a dermatitis reaction in harvesters of the cacti fruit. It's spines are frequently an uncomfortable nuisance to unwary soldiers exercising in BATUS. We report two cases of particularly debilitating adverse skin reactions to the cacti spines that occurred during the 2010 Exercise Prairie Thunder season.


Subject(s)
Dermatitis, Contact/etiology , Military Personnel , Opuntia/adverse effects , Skin/injuries , Wounds and Injuries/complications , Adult , Alberta/epidemiology , Dermatitis, Contact/diagnosis , Dermatitis, Contact/epidemiology , Diagnosis, Differential , Humans , Incidence , Male , Wounds and Injuries/diagnosis , Wounds and Injuries/epidemiology , Young Adult
9.
Appl Environ Microbiol ; 77(21): 7633-9, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21908627

ABSTRACT

Despite their importance in iron redox cycles and bioenergy production, the underlying physiological, genetic, and biochemical mechanisms of extracellular electron transfer by Gram-positive bacteria remain insufficiently understood. In this work, we investigated respiration by Thermincola potens strain JR, a Gram-positive isolate obtained from the anode surface of a microbial fuel cell, using insoluble electron acceptors. We found no evidence that soluble redox-active components were secreted into the surrounding medium on the basis of physiological experiments and cyclic voltammetry measurements. Confocal microscopy revealed highly stratified biofilms in which cells contacting the electrode surface were disproportionately viable relative to the rest of the biofilm. Furthermore, there was no correlation between biofilm thickness and power production, suggesting that cells in contact with the electrode were primarily responsible for current generation. These data, along with cryo-electron microscopy experiments, support contact-dependent electron transfer by T. potens strain JR from the cell membrane across the 37-nm cell envelope to the cell surface. Furthermore, we present physiological and genomic evidence that c-type cytochromes play a role in charge transfer across the Gram-positive bacterial cell envelope during metal reduction.


Subject(s)
Bioelectric Energy Sources/microbiology , Electrons , Peptococcaceae/isolation & purification , Peptococcaceae/metabolism , Biofilms/growth & development , Cryoelectron Microscopy , Electrodes/microbiology , Microscopy, Confocal , Oxidation-Reduction , Peptococcaceae/growth & development
10.
Appl Environ Microbiol ; 77(2): 684-7, 2011 Jan.
Article in English | MEDLINE | ID: mdl-21097590

ABSTRACT

The levels of integron abundance and diversity in soil amended with pig slurry were studied. Real-time PCR illustrated a significant increase in class 1 integron prevalence after slurry application, with increased prevalence still evident at 10 months after application. Culture-dependent data revealed 10 genera, including putative human pathogens, carrying class 1 and 2 integrons.


Subject(s)
Genetic Variation , Integrons , Manure/microbiology , Metagenome , Soil Microbiology , Agriculture/methods , Animals , Bacteria/classification , Bacteria/genetics , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , Molecular Sequence Data , Polymerase Chain Reaction , Prevalence , Sequence Analysis, DNA , Swine
11.
Antimicrob Agents Chemother ; 53(2): 696-702, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19064898

ABSTRACT

The prevalences of three sulfonamide resistance genes, sul1, sul2, and sul3 and sulfachloropyridazine (SCP) resistance were determined in bacteria isolated from manured agricultural clay soils and slurry samples in the United Kingdom over a 2-year period. Slurry from tylosin-fed pigs amended with SCP and oxytetracycline was used for manuring. Isolates positive for sul genes were further screened for the presence of class 1 and 2 integrons. Phenotypic resistance to SCP was significantly higher in isolates from pig slurry and postapplication soil than in those from preapplication soil. Of 531 isolates, 23% carried sul1, 18% sul2, and 9% sul3 only. Two percent of isolates contained all three sul genes. Class 1 and class 2 integrons were identified in 5% and 11.7%, respectively, of sul-positive isolates. In previous reports, sul1 was linked to class 1 integrons, but in this study only 8% of sul1-positive isolates carried the intI1 gene. Sulfonamide-resistant pathogens, including Shigella flexneri, Aerococcus spp., and Acinetobacter baumannii, were identified in slurry-amended soil and soil leachate, suggesting a potential environmental reservoir. Sulfonamide resistance in Psychrobacter, Enterococcus, and Bacillus spp. is reported for the first time, and this study also provides the first description of the genotypes sul1, sul2, and sul3 outside the Enterobacteriaceae and in the soil environment.


Subject(s)
Anti-Bacterial Agents/pharmacology , Drug Resistance, Bacterial/genetics , Manure/microbiology , Sewage/microbiology , Soil Microbiology , Sulfonamides/pharmacology , Animals , Colony Count, Microbial , Conjugation, Genetic , DNA, Bacterial/genetics , DNA, Bacterial/isolation & purification , Integrons/genetics , Microbial Sensitivity Tests , Oxytetracycline/pharmacology , RNA, Ribosomal/genetics , Swine , Tylosin/pharmacology , United Kingdom
14.
Br J Med Psychol ; 71 ( Pt 4): 509-23, 1998 Dec.
Article in English | MEDLINE | ID: mdl-9875959

ABSTRACT

The idiom of kinship is a powerful one that stretches across many levels of social behaviour (van den Berghe, 1979), and Daly, Salmon & Wilson (1997) recently outlined the basic principles of a comprehensive, evolution-based kinship psychology. Their approach merges traditional kinship theory, Hamilton's inclusive fitness model and the broader realm of evolutionary psychology into an exciting and provocative call to arms. They address biological, psychological (viz. fictive kinship) and kin-like levels of analysis, and they argue for a relationship-specific kinship psychology that deals with the particular demands of being a mother, father, mate, offspring or grandparent. Our particular approach to kinship psychology has focused primarily on the distinction between biological kinship and psychological kinship (Bailey, 1988; Bailey & Wood, 1993; Nava & Bailey, 1991), and more recently on the role of kin-like relations in psychotherapy and other social contexts (Bailey, 1997a; Wood, 1997). The kin-like category is especially noteworthy in modern industrialized countries where acquaintanceships and stranger-to-stranger interactions often predominate over biological and psychological kinships (Ahern & Bailey, 1997).


Subject(s)
Biological Evolution , Interpersonal Relations , Psychotherapy , Social Behavior , Humans , Pedigree , Psychology/trends
15.
J Clin Psychol ; 45(4): 587-94, 1989 Jul.
Article in English | MEDLINE | ID: mdl-2768498

ABSTRACT

Psychological kinship refers to valuing significant others as though they were members of one's own family. This construct has many implications for human relationships, including the client-therapist relationship (Bailey, 1988). A 60-item Kinship Scale was developed and administered to 63 undergraduates (39 females; 24 males), along with several other independent measures of sociality (Rubin Love and Liking scales; EPPS Affiliation, Nurturance, and Succorance scales; abbreviated UCLA Loneliness Scale) and the Spiritual Well-Being scales. Subjects took the Kinship, Love, and Liking scales under two cognitive sets, "closest family member" and "acquaintance," while the other scales were taken in regular fashion. The Kinship, Love, and Liking scales were all sensitive to the cognitive sets and appropriately yielded higher mean values and higher correlations with the independent measures vis-à-vis the "closest family member" as opposed to "acquaintance." Significant sex differences were noted, with stronger correlation patterns for males than females. Overall, the Kinship Scale performed very well and shows considerable promise for future research.


Subject(s)
Family , Interpersonal Relations , Love , Personality Development , Personality Tests , Adaptation, Psychological , Adult , Female , Humans , Male , Psychometrics , Psychotherapy , Social Support
16.
J Pers Assess ; 46(6): 639-46, 1982 Dec.
Article in English | MEDLINE | ID: mdl-16367626

ABSTRACT

Subjects were asked to list pleasures and aversions actually experienced, and pleasures and aversions based on their "innermost fantasies." A 7-point rating scale was developed to rate "primitive" and "advanced" elements in these pleasure-aversion responses. The "primitive" pole of the scale was keyed with the phrase "gut-level experiencing" and the "advanced" pole with "detached objective thinking." Reality Pleasure, Fantasy Pleasure, Reality Aversive, Fantasy Aversive, and Total scores were derived by having trained raters rate each subject's response with the 7-point rating scale. In Study 1, 25 females and 25 males provided pleasure-aversion responses and the data analyzed in a mixed 2 (male-female) x 2 (reality-fantasy) x 2 (pleasure-aversive) ANOVA. The most important finding was a highly significant reality-fantasy x pleasure-aversive interaction: subjects tended to "progress" (give more advanced responses) going from reality to fantasy in their pleasure responses, while exactly the opposite occurred with the aversive responses. Also, as predicted, reality aversive responses tended to be more "advanced" than reality pleasure responses. Study 2 was similar in design, but several additional personality measures were administered to assess the construct validity of the pleasure-aversion scores. As in Study l, the reality-fantasy x pleasure-aversive interaction was highly significant and again reflected a pattern of "progression" going from reality to fantasy for pleasure responses and "regression" for aversive responses. The correlation analysis also produced several interesting findings with sex serving as a major moderator variable.

17.
J Clin Psychol ; 35(4): 807-14, 1979 Oct.
Article in English | MEDLINE | ID: mdl-512012

ABSTRACT

Determined the efficacy of profile analysis with a prison population (63 white, 63 black) of the Petersburg Federal Correctional Institution as Ss. By use of Veldman's Hierarchical Profile Analysis, five distinctive WAIS profile types were derived empirically for each racial group. Analyses of covariance that controlled for full-scale IQ differences revealed significant differences among the profile types within each race in terms of Stanford Achievement Test scores and MMPI T-scores. Further, partial correlations indepepdent of full-scale IQ revealed significant relationships between some of the profile types and the commission of rule infractions while incarcerated. These findings are interpreted as supportive of profile analysis with inmate populations. However, it is suggested that further research be effected to cross-validate these findings.


Subject(s)
Prisoners/psychology , Wechsler Scales , Adolescent , Adult , Analysis of Variance , Antisocial Personality Disorder/psychology , Ethnicity , Humans , Intelligence , MMPI , Male
18.
J Clin Psychol ; 35(2): 341-5, 1979 Apr.
Article in English | MEDLINE | ID: mdl-457896

ABSTRACT

Previous research (Bailey, Lazar, & Edinger, 1977) has indicated the presence of Breadth and Depth factors on the Similarities subscale of the WAIS. The present study (N = 102) analyzed these two factors further, by using measures of Breadth and Depth on both the Similarities and Vocabulary subscales. Several other measures also were studied, including a Comprehension index, SAT scores, and GPA. Results of a factor analysis with oblique rotation revealed distinct Breadth and Depth factors, which strongly supported the theoretical rationale of the study. The Breadth factor seems to reflect broad-range skills of the type required on conventional IQ tests, while the Depth factor is less theoretically clear. It is suggested that Depth involves an effort component as well as ability because the S is required to provide more than a single correct answer for a given item.


Subject(s)
Vocabulary , Wechsler Scales , Adult , Factor Analysis, Statistical , Female , Humans , Male
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