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The influence of repetitive transcranial magnetic stimulation (rTMS) on mood in healthy people is uncertain, as former studies show divergent results. Previous studies in healthy volunteers focused exclusively on the immediate effect of a single session of rTMS on mood.
The aim of this study was to analyse the influence on mood of a series of 9 High Frequency (HF) rTMS stimulations of the left dorsolateral prefrontal cortex (DLPFC).
44 young healthy male volunteers were randomly assigned to receive 9 sessions of active HF-rTMS (n = 22) or sham rTMS (n = 22) over the left DLPFC. Each session in the active group consisted of 15 trains of 25 Hz starting with 100% of motor threshold. Sham stimulation was performed following the same protocol, but using a sham coil. The variables of interest were the Beck Depression Inventory (BDI) and Visual Analogue Scales (VAS) which quantified “mood”, “enjoyment” and “energy”.
We found a significant reduction of the BDI score in the active group (GLM, p < 0.001) whereas no significant changes of the BDI score were caused by sham stimulation (GLM, p = 0.109). We did not find significant differences caused by active or sham stimulation in VAS scales except for the VAS labelled lively/gloomy immediately after stimulation. The active group was found to be more “gloomy” (p = 0.001).
Our data support the hypothesis that a 9-day long series of HF-rTMS of the left DLPFC improves mood, analysed by BDI in healthy young men.
Patients with a first episode psychosis (FEP) have repeatedly been shown to have gray matter (GM) volume alterations. Some of these neuroanatomical abnormalities are already evident in the at-risk mental state (ARMS) for psychosis. Not only GM alterations but also neurocognitive impairments predate the onset of frank psychosis with verbal learning and memory (VLM) being among the most impaired domains. Yet, their interconnection with alterations in GM volumes remains ambiguous.
To evaluate associations of different subcortical GM volumes in the medial temporal lobe with VLM performance in ARMS and FEP patients.
Data were collected within the prospective Früherkennung von Psychosen (FePsy) study, which aims to improve the early detection of psychosis. VLM was assessed using the California Verbal Learning Test (CVLT) and its latent variables Attention Span (AS), Learning Efficiency (LE), Delayed Memory (DM) and Inaccurate Memory (IM). Structural images were acquired using a 3 Tesla magnetic resonance imaging scanner.
Data from 59 ARMS and 47 FEP patients were analysed. Structural equation models revealed significant associations between the amygdala and AS, LE and IM; thalamus and LE and IM; and the caudate, hippocampus and putamen with IM. However, none of these significant results withstood correction for multiple testing.
Although VLM is among the most impaired cognitive domains in emerging psychosis, we could not find an association between low performance in this domain and reductions in subcortical GM volumes. Our results suggest that deficits in this domain may not stem from alterations in subcortical structures.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
There is a long history of exploitation of the South American river turtle Podocnemis expansa. Conservation efforts for this species started in the 1960s but best practices were not established, and population trends and the number of nesting females protected remained unknown. In 2014 we formed a working group to discuss conservation strategies and to compile population data across the species’ range. We analysed the spatial pattern of its abundance in relation to human and natural factors using multiple regression analyses. We found that > 85 conservation programmes are protecting 147,000 nesting females, primarily in Brazil. The top six sites harbour > 100,000 females and should be prioritized for conservation action. Abundance declines with latitude and we found no evidence of human pressure on current turtle abundance patterns. It is presently not possible to estimate the global population trend because the species is not monitored continuously across the Amazon basin. The number of females is increasing at some localities and decreasing at others. However, the current size of the protected population is well below the historical population size estimated from past levels of human consumption, which demonstrates the need for concerted global conservation action. The data and management recommendations compiled here provide the basis for a regional monitoring programme among South American countries.
Recent evidence shows that the serotonin 2A receptor (5-hydroxytryptamine2A receptor, 5-HT2AR) is critically involved in the formation of visual hallucinations and cognitive impairments in lysergic acid diethylamide (LSD)-induced states and neuropsychiatric diseases. However, the interaction between 5-HT2AR activation, cognitive impairments and visual hallucinations is still poorly understood. This study explored the effect of 5-HT2AR activation on response inhibition neural networks in healthy subjects by using LSD and further tested whether brain activation during response inhibition under LSD exposure was related to LSD-induced visual hallucinations.
In a double-blind, randomized, placebo-controlled, cross-over study, LSD (100 µg) and placebo were administered to 18 healthy subjects. Response inhibition was assessed using a functional magnetic resonance imaging Go/No-Go task. LSD-induced visual hallucinations were measured using the 5 Dimensions of Altered States of Consciousness (5D-ASC) questionnaire.
Relative to placebo, LSD administration impaired inhibitory performance and reduced brain activation in the right middle temporal gyrus, superior/middle/inferior frontal gyrus and anterior cingulate cortex and in the left superior frontal and postcentral gyrus and cerebellum. Parahippocampal activation during response inhibition was differently related to inhibitory performance after placebo and LSD administration. Finally, activation in the left superior frontal gyrus under LSD exposure was negatively related to LSD-induced cognitive impairments and visual imagery.
Our findings show that 5-HT2AR activation by LSD leads to a hippocampal–prefrontal cortex-mediated breakdown of inhibitory processing, which might subsequently promote the formation of LSD-induced visual imageries. These findings help to better understand the neuropsychopharmacological mechanisms of visual hallucinations in LSD-induced states and neuropsychiatric disorders.
An exceptional fauna of retiolitine graptolites from Aeronian and lowermost Telychian strata in Arctic Canada provides significant new insights into the phylogeny and history of diversity of retiolitine graptolites. All specimens were isolated by dissolution of calcite concretions. The results indicate that retiolitines emerged within the lower Aeronian and reached a higher than expected level of diversity and disparity of forms by mid-Aeronian time. The uppermost Aeronian is almost totally devoid of preserved graptolites in Arctic Canada and, therefore, our material provides few new insights into retiolitine morphology or diversity through that interval. Specimens assigned to Pseudoretiolites? sp. occur in well-dated lower Aeronian strata, thus representing the lowest known biostratigraphic occurrences of retiolitines globally. This taxon appears to be morphologically primitive in that the sicula is completely preserved, with preservation of the proximal regions of theca 11, as well as distal thecal fusellum on mature specimens. Cladistic analysis of the Llandovery retiolitines shows that Pseudoretiolites is a stem genus for all of the other retiolitine taxa, which comprise two clades: one consisting of Pseudoplegmatograptus, Retiolites, and Stomatograptus and their derivatives; and the other includes Rotaretiolites, Aeroretiolites, Aeroretiolites?, Eorograptus, Paraplectograptus, Paraplectograptus?, and Sokolovograptus, and all of those other taxa that had previously been placed in the Plectograptinae. We follow the recent proposal that all of the taxa traditionally assigned to the Retiolitidae be assigned to the subfamily Retiolitinae. The following new taxa are described: Pseudoretiolites hyrichus n. sp., Eorograptus spirifer n. sp., and Aeroretiolites cancellatus n. gen. n. sp.
Although fear of falling is prevalent among older adults recovering from hip fracture, current instruments are inadequate due to focus on specific situations and measurement of self-efficacy rather than fear.
The authors revised and tested a form of the Fear of Falling Questionnaire with three groups of older adults: 405 recovering from hip fracture, 89 healthy community dwelling, and 42 with severe fear of falling. Test-retest reliability was evaluated in a subsample of 16 hip fracture patients. Internal consistency was compared across all groups. Construct validity was established through factor analysis, convergent validity with a measure of fall-related self-efficacy, and discriminant validity with measures of depression and affect.
A revised two-factor, six-item scale appears to have adequate psychometric properties. Scores were lower in the healthy comparison group relative to the hip fracture and fear of falling groups. Cronbach's α ranged from 0.72–0.83, with test-retest reliability of 0.82. Correlations with a measure of fall-related self-efficacy were moderate for the hip fracture group (0.42) and high with the healthy comparison (0.68) and fear of falling (0.70) groups. Correlations with depression and negative and positive affect were low to moderate.
The Fear of Falling Questionnaire – Revised shows promise as a self-report measure of fear of falling, and is one of the first to be tested in older adults recovering from hip fracture. Advantages are that it is global rather than situation-specific and measures fear rather than self-efficacy. Future research on this scale is recommended in other older adult samples for whom fear of falling is relevant.
We present the development of highly efficient merocyanine solar cells at the example of the dye MD376. Due to their unique processing flexibility, merocyanines have been applied in solution- as well as vacuum-processed organic photovoltaics. In fully vapor-deposited MD376 single cells, efficiencies up to 5.0% were achieved while maintaining a rather simple device setup with only four organic layers. Moreover, MD376 has been successfully introduced to vacuum-processed tandem cell structures, reporting a high open-circuit voltage of 2.1 V.
Although individuals vulnerable to psychosis show brain volumetric abnormalities, structural alterations underlying different probabilities for later transition are unknown. The present study addresses this issue by means of voxel-based morphometry (VBM).
We investigated grey matter volume (GMV) abnormalities by comparing four neuroleptic-free groups: individuals with first episode of psychosis (FEP) and with at-risk mental state (ARMS), with either long-term (ARMS-LT) or short-term ARMS (ARMS-ST), compared to the healthy control (HC) group. Using three-dimensional (3D) magnetic resonance imaging (MRI), we examined 16 FEP, 31 ARMS, clinically followed up for on average 3 months (ARMS-ST, n=18) and 4.5 years (ARMS-LT, n=13), and 19 HC.
The ARMS-ST group showed less GMV in the right and left insula compared to the ARMS-LT (Cohen's d 1.67) and FEP groups (Cohen's d 1.81) respectively. These GMV differences were correlated positively with global functioning in the whole ARMS group. Insular alterations were associated with negative symptomatology in the whole ARMS group, and also with hallucinations in the ARMS-ST and ARMS-LT subgroups. We found a significant effect of previous antipsychotic medication use on GMV abnormalities in the FEP group.
GMV abnormalities in subjects at high clinical risk for psychosis are associated with negative and positive psychotic symptoms, and global functioning. Alterations in the right insula are associated with a higher risk for transition to psychosis, and thus may be related to different transition probabilities.
In this article we discuss the applicability of global
scattering functions for structure analysis of Grazing Incidence Small Angle
X-ray Scattering (GISAXS) data. Contrary to rigorous analysis of the full
2-D detector image, which can be performed with complex simulation models,
the global scattering functions described here will be used to model
transverse detector scans in the
planes. In contrast to a full GISAXS analysis, this procedure cannot explain
structural features perpendicular to the sample plane. The discussed method
is useful for the analysis of weakly correlated films. These films are e.g.
found in polymer inorganic composite materials based on commercially
available nanoparticles. In hybrid material systems polydisperse structures,
including particle aggregates without precisely defined shape are formed.
The pictured approach, which models scattering in terms of structural
levels, has been previously applied with success in conventional
transmission SAXS geometry. It is based on conventional exponential and
power laws. Hence, data analysis becomes less complex compared to simulation
approaches. Here we examine if this unified fitting model can be used to
model diffuse, non specular scattering resulting from GISAXS. In this
context the applicability and limit of its application to diffuse scattering
in the GISAXS geometry is discussed. Furthermore diffuse
scattering from different ideal particle types is simulated and compared
with fitted results. To verify our approach, fit results from experimental
GISAXS curves obtained for real samples are compared with results from
Scanning Probe Microscopy and Scanning Electron Microscopy studies. The
samples investigated range from evaporated Au films to hybrid
TiO2/polymer films and demonstrate the usefulness in the structural
analysis of complex films.
In 2001, Lenz and Kozłowska-Dawidziuk assigned the name Sagenograptus (species name S. arctos) to a late Wenlock retiolitid graptolite from Arctic Canada. We thank Rimma Sobolevskaya for subsequently informing us that the name Sagenograptus (species S. gagarini) had, already in 1962, been applied by Obut and Sobolevskaya to a Tremadoc dendroid graptolite from Taimyr. The generic name for the Arctic Wenlock retiolitid is here changed to Sagenograptoides.
Body image distortion is a key symptom of anorexia nervosa. In behavioral research two components of body image have been defined: attitudes towards the body and body size experience. Neuroimaging studies concerning own body image distortions in anorexia nervosa have revealed an inconsistent pattern of results and are constrained by the fact that no direct distinction between the different parts of body image has been made.
The present study therefore set out to investigate the neural correlates of two parts of the own body image using functional magnetic resonance imaging (fMRI): satisfaction rating and size estimation for distorted own body photographs in patients with anorexia nervosa and controls.
Anorectic patients were less satisfied with their current body shape than controls. Patients further demonstrated stronger activation of the insula and lateral prefrontal cortex during the satisfaction rating of thin self-images. This indicates a stronger emotional involvement when patients are presented with distorted images close to their own ideal body size. Patients also overestimated their own body size. We were able to show complex differential modulations in activation of the precuneus during body size estimation in control and anorectic subjects. It could be speculated that a deficit in the retrieval of a multimodal coded body schema in precuneus/posterior parietal cortex is related to body size overestimation.
We were able to find specific behavioral responses and neural activation patterns for two parts of body image in anorexia nervosa and healthy controls. Thus, the present results underline the importance of developing research and therapeutic strategies that target the two different aspects of body image separately.
This paper documents the arrival of Diplosoma listerianum into a habitat with no previously known history of the species. Once established, D. listerianum exploited rapid growth rates relative to the other fouling species present, to quickly become the dominant species in a local fouling assemblage. Most resident macrofoulers were out-competed for space and overgrown, although some resistance to overgrowth was demonstrated by the bryozoan Umbonula littoralis and the tunicate Ascidiella aspersa. In this instance, traits traditionally considered to be relevant for community resistance towards invasion, such as diversity, richness, dominant species identity and open space were not important in controlling the spread of D. listerianum.
This paper presents a description of new gastropods belonging to the superfamily Porcellioidea (Vetigastropoda) from the richly diverse Lower Devonian gastropod fauna of the Road River Formation in the Royal Creek area, Yukon Territory. This fauna belongs to Western Canada Province of the Old World Realm. The Pragian species Porcellia (Porcellia) yukonensis n. sp. and Porcellia (Paraporcellia) sp. represent the oldest presently known members of subgenera Porcellia (Porcellia) and Porcellia (Paraporcellia). Their simple shell ornamentation fits well with an earlier described evolutionary trend in shell morphology of the Porcellinae. Late Pragian to early Emsian Perryconcha pulchra n. gen. and n. sp. is the first member of the Porcellioidea bearing a row of tremata on adult teleoconch whorls. The occurrence of this shell feature in the Porcellioidea is additional evidence that the evolution of the apertural slit was much more complicated than has been proposed in classical models of Paleozoic gastropod evolution.
Taxa belonging to the Ceratoikiscidae are described in detail from two measured sections of Member C of the Cape Phillips Formation exposed along Rookery Creek, Cornwallis Island, Arctic Canada. The sections encompass uppermost Sheinwoodian (top lower Wenlock) to the base of the Gorstian (base Ludlow) and are dated by graptolites assigned to the Cyrtograptus perneri–Monograptus opimus Zone (upper Sheinwoodian), the Cyrtograptus lundgreni Zone (lower Homerian), and the Colonograptus praedeubeli–Colonograptus deubeli Zone (upper Homerian). Radiolarians are found in great abundance throughout the lower Homerian, allowing for the establishment of the first appearance of the genus Helenifore Ormiston and Nazarov. Helenifore is emended to accommodate the Silurian species H. quadrispina n. sp. and H. speciosus (Furutani 1990). One new genus, Kappaforma, including the new species, K. insecta, is described, as is the new species H. quadrispina. Ceratoikiscum octapleura Renz and C. armiger Furutani are synonymized with C. lenoides Renz, and H. planus Umeda is synonymized with H. speciosus.
We have compared the outer membrane protein (OMP) pattern of sessile Pseudomonas aeruginosa cells with that of its stationary-phase free-floating counterparts. Two-dimensional electrophoretic gels were compared using computing scanning densitometry. The level of 103 OMPs (i.e. about 50% of the spots that fulfilled our statistical selection threshold) was significantly and reproducibly different in biofilm organisms as compared with their planktonic counterparts. Some OMPs that specifically either accumulated or decreased were identified by mass spectrometry and the role of these proteins in the biofilm phenotype is discussed.
The first dedicated local electrode atom probes (LEAP [a
trademark of Imago Scientific Instruments Corporation]) have been
built and tested as commercial prototypes. Several key performance
parameters have been markedly improved relative to conventional
three-dimensional atom probe (3DAP) designs. The Imago LEAP can operate
at a sustained data collection rate of 1 million atoms/minute. This
is some 600 times faster than the next fastest atom probe and large
images can be collected in less than 1 h that otherwise would take many
days. The field of view of the Imago LEAP is about 40 times larger than
conventional 3DAPs. This makes it possible to analyze regions that are
about 100 nm diameter by 100 nm deep containing on the order of 50 to
100 million atoms with this instrument. Several example applications
that illustrate the advantages of the LEAP for materials analysis are
Background and objective: Acute isovolaemic haemodilution increases local and mean cerebral blood flow. It is not known whether a single haemodilution has a short-term effect only or whether it affects cerebral perfusion over a longer time period. In the present study, local and mean cerebral blood flow were determined in conscious rats after a 4, 24 and 48 h period following one-time haemodilution.
Methods: Thirty-six rats were randomized to three untreated sham groups and three groups of haemodilution (4, 24 or 48 h, n = 6 for each group). Isovolaemic haemodilution with albumin 5% aimed to a target haematocrit of 0.2. Local cerebral blood flow was measured in 38 brain regions by the iodo-[14C]antipyrine method in conscious normothermic rats.
Results: Isovolaemic haemodilution reduced haematocrit from 0.44 to 0.20. During the following 24 and 48 h periods, haematocrit remained low (0.22 and 0.21). Mean cerebral blood flow was similar in untreated sham groups (88 ± 12 after 4 h, 92 ± 11 after 24 h, 96 ± 10 mL 100 g−1 min−1 after 48 h). Haemodilution increased mean cerebral blood flow after 4 h (184 ± 11 mL 100 g−1 min−1), after 24 h (153 ± 13 mL 100 g−1 min−1) and 48 h (149 ± 15 mL 100 g−1 min−1) (P ≤ 0.05). Local cerebral blood flow increased in all 38 structures after 4 h haemodilution but decreased with time in six of 38 brain structures after 24 h and in 15 regions after 48 h (P ≤ 0.05).
Conclusions: A single one-time haemodilution increased mean cerebral blood flow for 2 days. However, local adaptation of cerebral blood flow to a chronic low haematocrit occurred but was heterogeneous within the brain.