9,751 research outputs found
Dates of birth and seasonal changes in well-being among 4904 subjects completing the seasonal pattern assessment questionnaire
Background: Abnormal distributions of birthdates, suggesting intrauterine aetiological factors, have been found in several psychiatric disorders, including one study of out-patients with Seasonal Affective Disorder (S.A.D.). We investigated birthdate distribution in relation to seasonal changes in well-being among a cohort who had completed the Seasonal Pattern Assessment Questionnaire (SPAQ). Method: A sample of 4904 subjects, aged 16 to 64, completed the SPAQ. 476 were cases of S.A.D. on the SPAQ and 580 were cases of sub-syndromal S.A.D. (S-S.A.D.). 92 were interview confirmed cases of S.A.D. Months and dates of birth were compared between S.A.D. cases and all others, between S.A.D. and S-S.A.D. cases combined and all others, and between interview confirmed cases and all others. Seasonality, as measured through seasonal fluctuations in well-being on the Global Seasonality Scores (GSS) of the SPAQ, was compared for all subjects by month and season of birth. Results: There was no evidence of an atypical pattern of birthdates for subjects fulfilling criteria for S.A.D., for the combined S.A.D. / S-S.A.D. group or for interview confirmed cases. There was also no relationship between seasonality on the GSS and month or season of birth. Limitations: Diagnoses of S.A.D. made by SPAQ criteria are likely to be overinclusive. Conclusion: Our findings differ from studies of patients with more severe mood disorders, including psychiatric out-patients with S.A.D. The lack of association between seasonality and birthdates in our study adds credence to the view that the aetiology of S.A.D. relates to separable factors predisposing to affective disorders and to seasonality
Carboplatin binding to a model protein in non-NaCl conditions to eliminate partial conversion to cisplatin, and the use of different criteria to choose the resolution limit
Hen egg white lysozyme (HEWL) co-crystallisation conditions of carboplatin
without sodium chloride (NaCl) have been utilised to eliminate partial
conversion of carboplatin to cisplatin observed previously. Tetragonal HEWL
crystals were successfully obtained in 65% MPD with 0.1M citric acid buffer at
pH 4.0 including DMSO. The X-ray diffraction data resolution to be used for the
model refinement was reviewed using several topical criteria together. The
CC1/2 criterion implemented in XDS led to data being significant to 2.0{\AA},
compared to the data only being able to be processed to 3.0{\AA} using the
Bruker software package (SAINT). Then using paired protein model refinements
and DPI values based on the FreeR value, the resolution limit was fine tuned to
be 2.3{\AA}. Interestingly this was compared with results from the EVAL
software package which gave a resolution limit of 2.2{\AA} solely using
crossing 2, but 2.8{\AA} based on the Rmerge values (60%). The
structural results showed that carboplatin bound to only the N{\delta} binding
site of His-15 one week after crystal growth, whereas five weeks after crystal
growth, two molecules of carboplatin are bound to the His-15 residue. In
summary several new results have emerged: - firstly non-NaCl conditions showed
a carboplatin molecule bound to His-15 of HEWL; secondly binding of one
molecule of carboplatin was seen after one week of crystal growth and two
molecules were bound after five weeks of crystal growth; and thirdly the use of
several criteria to determine the diffraction resolution limit led to the
successful use of data to higher resolution.Comment: 14 pages; submitted to Acta Cryst D Biological Crystallography
reference number tz504
Optical Quantum Computation with Perpetually Coupled Spins
The possibility of using strongly and continuously interacting spins for
quantum computation has recently been discussed. Here we present a simple
optical scheme that achieves this goal while avoiding the drawbacks of earlier
proposals. We employ a third state, accessed by a classical laser field, to
create an effective barrier to information transfer. The mechanism proves to be
highly efficient both for continuous and pulsed laser modes; moreover it is
very robust, tolerating high decay rates for the excited states. The approach
is applicable to a broad range of systems, in particular dense structures such
as solid state self-assembled (e.g., molecular) devices. Importantly, there are
existing structures upon which `first step' experiments could be immediately
performed.Comment: 5 pages including 3 figures. Updated to published versio
Ensemble based quantum metrology
The field of quantum metrology promises measurement devices that are
fundamentally superior to conventional technologies. Specifically, when quantum
entanglement is harnessed the precision achieved is supposed to scale more
favourably with the resources employed, such as system size and the time
required. Here we consider measurement of magnetic field strength using an
ensemble of spins, and we identify a third essential resource: the initial
system polarisation, i.e. the low entropy of the original state. We find that
performance depends crucially on the form of decoherence present; for a
plausible dephasing model, we describe a quantum strategy which can indeed beat
the standard quantum limit
Quantum metrology with molecular ensembles
This work was supported by the EPSRC through QIP IRC (Grants No. GR/S82176/01 and No. GR/S15808/01), the National Research Foundation and Ministry of Education, Singapore, the DAAD, and the Royal Society.The field of quantum metrology promisesmeasurement devices that are fundamentally superior to conventional technologies. Specifically, when quantum entanglement is harnessed, the precision achieved is supposed to scale more favorably with the resources employed, such as system size and time required. Here, we consider measurement of magnetic-field strength using an ensemble of spin-active molecules. We identify a third essential resource: the change in ensemble polarization (entropy increase) during the metrology experiment. We find that performance depends crucially on the form of decoherence present; for a plausible dephasing model, we describe a quantum strategy, which can indeed beat the standard strategy.Publisher PDFPeer reviewe
Metagenetic analysis of patterns of distribution and diversity of marine meiobenthic eukaryotes
AimMeiofaunal communities that inhabit the marine benthos offer unique opportunities to simultaneously study the macroecology of numerous phyla that exhibit different life-history strategies. Here, we ask: (1) if the macroecology of meiobenthic communities is explained mainly by dispersal constraints or by environmental conditions; and (2) if levels of meiofaunal diversity surpass existing estimates based on morphological taxonomy. LocationUK and mainland European coast. MethodsNext-generation sequencing techniques (NGS; Roche 454 FLX platform) using 18S nuclear small subunit ribosomal DNA (rDNA) gene. Pyrosequences were analysed using AmpliconNoise followed by chimera removal using Perseus. ResultsRarefaction curves revealed that sampling saturation was only reached at 15% of sites, highlighting that the bulk of meiofaunal diversity is yet to be discovered. Overall, 1353 OTUs were recovered and assigned to 23 different phyla. The majority of sampled sites had c. 60-70 unique operational taxonomic units (OTUs) per site, indicating high levels of beta diversity. The environmental parameters that best explained community structure were seawater temperature, geographical distance and sediment size, but most of the variability (R-2=70%-80%) remains unexplained. Main conclusionsHigh percentages of endemic OTUs suggest that meiobenthic community composition is partly niche-driven, as observed in larger organisms, but also shares macroecological features of microorganisms by showing high levels of cosmopolitanism (albeit on a much smaller scale). Meiobenthic communities exhibited patterns of isolation by distance as well as associations between niche, latitude and temperature, indicating that meiobenthic communities result from a combination of niche assembly and dispersal processes. Conversely, isolation-by-distance patterns were not identified in the featured protists, suggesting that animals and protists adhere to radically different macroecological processes, linked to life-history strategies.Natural Environment Research Council (NERC) [NE/E001505/1, NE/F001266/1, MGF-167]; Portuguese Foundation for Science and Technology (FCT) [SFRH/BD/27413/2006, SFRH/BPD/80447/2014]; EPSRC [EP/H003851/1]; BBSRC CASE studentship; Unilever; Biotechnology and Biological Sciences Research Council [987347]; Engineering and Physical Sciences Research Council [EP/H003851/1]; Natural Environment Research Council [NE/F001290/1, NE/F001266/1, NE/E001505/1, NBAF010002]info:eu-repo/semantics/publishedVersio
Intraocular pressure in inbred mouse strains
PURPOSE: To develop a protocol to measure the intraocular pressure (IOP) of living mice and to determine the IOP of genetically different mouse strains. METHODS: Eyes of anesthetized animals were cannulated with a very fine fluid-filled glass microneedle. The microneedle was connected to a pressure transducer, and the pressure signal was analyzed with a computer system. Intraocular pressures of male C3H/He iota, C57BL/ 6 iota, A/iota, and BALB/c iota mice were determined. RESULTS: Differences in IOP were detected between genetically distinct mouse strains maintained in virtually identical environments. C3H/He iota was the strain with the highest average IOP (13.7 +/- 0.8 mm Hg). This strain average was 1.4 mm Hg higher than that for C57BL/6 iota (12.3 +/- 0.5 mm Hg; P = 0.14), 4.3 mm Hg higher than that for A/iota (9.4 +/- 0.5 mm Hg; P < 0.001), and 6 mm Hg higher than that for BALB/c iota (7.7 +/- 0.5 mm Hg; P < 0.001). CONCLUSIONS: The authors have developed an accurate and reliable procedure for measuring intraocular pressure in living mice. This procedure can detect IOP differences between groups of mice that differ by genotype
Ocular hypertension suppresses homeostatic gene expression in optic nerve head microglia of DBA/2 J mice.
Glaucoma is the leading cause of irreversible vision loss. Ocular hypertension is a major risk factor for glaucoma and recent work has demonstrated critical early neuroinflammatory insults occur in the optic nerve head following ocular hypertension. Microglia and infiltrating monocytes are likely candidates to drive these neuroinflammatory insults. However, the exact molecular identity / transcriptomic profile of microglia following ocular hypertensive insults is unknown. To elucidate the molecular identity of microglia after long-term exposure to ocular hypertension, we used a mouse model of glaucoma (DBA/2 J). We performed RNA-sequencing of microglia mRNA from the optic nerve head at a time point following ocular hypertensive insults, but preceding detectable neurodegeneration (with microglia identified as being CD4
Погляд на архіви
The International Union of Crystallography has for many years been advocating archiving of raw data to accompany structural papers. Recently, it initiated the formation of the Diffraction Data Deposition Working Group with the aim of developing standards for the representation of these data. A means of studying this issue is to submit exemplar publications with associated raw data and metadata. A recent study on the effects of dimethyl sulfoxide on the binding of cisplatin and carboplatin to histidine in 11 different lysozyme crystals from two diffractometers led to an investigation of the possible effects of the equipment and X-ray diffraction data processing software on the calculated occupancies and B factors of the bound Pt compounds. 35.3 Gb of data were transferred from Manchester to Utrecht to be processed with EVAL. A systematic comparison shows that the largest differences in the occupancies and B factors of the bound Pt compounds are due to the software, but the equipment also has a noticeable effect. A detailed description of and discussion on the availability of metadata is given. By making these raw diffraction data sets available via a local depository, it is possible for the diffraction community to make their own evaluation as they may wish
Jingoism, Public Opinion, and the New Imperialism:Newspapers and imperial rivalries at the fin de siècle
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