Improved Measurement of the Evolution of the Reactor Antineutrino Flux and Spectrum at Daya Bay

Reactor neutrino experiments play a crucial role in advancing our knowledge of neutrinos. In this Letter, the evolution of the flux and spectrum as a function of the reactor isotopic content is reported in terms of the inverse-beta-decay yield at Daya Bay with 1958 days of data and improved systematic uncertainties. These measurements are compared with two signature model predictions: the Huber-Mueller model based on the conversion method and the SM2018 model based on the summation method. The measured average flux and spectrum, as well as the flux evolution with the ^{239}Pu isotopic fraction, are inconsistent with the predictions of the Huber-Mueller model. In contrast, the SM2018 model is shown to agree with the average flux and its evolution but fails to describe the energy spectrum. Altering the predicted inverse-beta-decay spectrum from ^{239}Pu fission does not improve the agreement with the measurement for either model. The models can be brought into better agreement with the measurements if either the predicted spectrum due to ^{235}U fission is changed or the predicted ^{235}U, ^{238}U, ^{239}Pu, and ^{241}Pu spectra are changed in equal measure.

Precision Measurement of Reactor Antineutrino Oscillation at Kilometer-Scale Baselines by Daya Bay

We present a new determination of the smallest neutrino mixing angle θ_{13} and the mass-squared difference Δm_{32}^{2} using a final sample of 5.55×10^{6} inverse beta-decay (IBD) candidates with the final-state neutron captured on gadolinium. This sample is selected from the complete dataset obtained by the Daya Bay reactor neutrino experiment in 3158 days of operation. Compared to the previous Daya Bay results, selection of IBD candidates has been optimized, energy calibration refined, and treatment of backgrounds further improved. The resulting oscillation parameters are sin^{2}2θ_{13}=0.0851±0.0024, Δm_{32}^{2}=(2.466±0.060)×10^{-3}  eV^{2} for the normal mass ordering or Δm_{32}^{2}=-(2.571±0.060)×10^{-3}  eV^{2} for the inverted mass ordering.

P18.03.B Long term effects of therapeutic embolization of radiographically suspected meningiomas regarding tumour- and necrosis volume as well as patients' symptoms

Background

Preoperative embolization of radiographically suspected intracranial meningiomas is performed to reduce intraoperative blood loss and to facilitate resection. However, there is paucity of evidence examining the effect of embolization as a sole intervention on the tumor volume and the patient's neurocognitive symptoms. The objective of this study was to investigates the influence of therapeutic embolization on tumor- and necrosis volume and neurocognitive symptoms in absence of surgical intervention.

Material and Methods

Between January 2019 and June 2021, 4 patients (median age 82, 1 female) with 5 radiographically suspected intracranial meningiomas, underwent endovascular embolization with liquid embolizate and coils, without subsequent surgery. Indication for embolization was history of previous multiple surgery contraindicating further surgical intervention or patients will. Neurological status (on admission, discharge from hospital and 5 months after embolization), medical history, medication, MRI (location, tumor- and necrosis volume, development of edema, complications), DSA (extent of embolization, arterial supply) and procedural complications were recorded. In 3 patients with 4 tumors, an MRI scan was performed. The calculation of tumor- and necrosis volume was done manually with a semiautomatic segmentation tool. One patient with one tumor received CT scans due to a cardiac pacemaker and was therefore excluded from volumetric analysis.

Results

The average tumor volume was 44,83 ± 13,82 cm3 on admission, 45,33 ± 16,3 cm3 5 days after embolization (+1%) and 39,93 ± 29,39 cm3 (-11%) after 5 months. The average necrosis diameter was 41,76 ± 9,33 mm after 5 days and 6,05 ± 6,43 mm after 5 months. The perifocal oedema decreased in 2/3 Patients. Tumor blood supply was via 2,4 ± 1,34 vessels, 1,2 ± 0,45 vessels were embolised. On admission, 3 patients showed neurocognitive symptoms. At discharge and in the follow-up, in 2 patients the symptoms had improved, one patient experienced a complete symptom regression. In one patient the embolization was complicated by dissection of the middle meningeal artery. The same patients perifocal oedema increased in the further clinical course with accompanying deterioration of the pre-existing hemiparesis from moderate to severe. Supported with dexamethasone medication, the oedema and symptoms declined to a mild residual paresis. None of the patients developed a long-term neurocognitive deficit related to embolization.

Conclusion

Therapeutic endovascular embolization of radiographically suspected intracranial meningiomas reduced the tumor volume and led to long-term improvement of pre-existing neurocognitive symptoms. In the future, these effects should be verified in larger studies.

P18.02.B Influence of preoperative embolization on intraoperative parameters, hospital stay and neurocognitive outcome compared to surgery alone

Background

Preoperative embolization of meningiomas is used to reduce intraoperative blood loss and facilitate resection. So far, a risk-benefit stratification of this additional intervention on the neurocognitive outcome is missing. This study investigates the influence of preoperative embolization with liquid Embolisate on intraoperative parameters, length of hospital stays and functional outcome.

Material and Methods

Patients treated for intracranial meningiomas at a single center between January 2019 and June 2021 were reviewed in a retrospective matched-pair analysis. Patients were matched to group A (tumor resected) and group B (preoperatively embolized and tumor resected after 2,27 ± 3,05 days). Matching criteria were tumor diameter and location (convexity, falx cerebri or skull base, frontal, parietal, occipital, temporal). Data collection included MRI (location, tumor- and necrosis volume, edema, complications), DSA (tumor blush, arterial supply), medical history, histological, surgical, clinical course, complications, and haematological parameters, as well as neurocognitive symptoms on admission and discharge from hospital.

Results

44 patients with intracranial Meningiomas were included, divides into 2 groups, each encompassing 22 patients (mean age 62,41 years, 40,5% female). The matching criteria tumor diameter (64.21 vs. 63.55 mm, p=0.725) and tumor localisation (p=0.381) showed no significant differences. There were no significant differences in postoperative hospital stay (14.41 ± 9.5 vs. 14.25 ± 16.88 days, p=0.814) and in preoperative perifocal oedema (82% vs. 82%, p=0.397). Preoperative embolization was associated with decreased intraoperative tumor bleeding (67% vs. 14%, p=0.001, PHI= 0.534), longer duration of surgery (4:58 ± 2:44 vs. 06:07 ± 03:00 hours, p=0.037), trend for decrease in perifocal oedema (p=0.052, PHI=0,498), neurocognitive improvement on discharge from hospital (23% vs. 86%, p=0.045, PHI=0.339) and decreased of epileptic seizures (preoperative 18% vs. 18% and postoperative 23% vs. 5%). There was no increase in cumulative complication rate (p=1.0) and no long-term neurocognitive impairments associated with embolization.

Conclusion

This study suggests that preoperative embolization of intracranial meningiomas significantly decreased intraoperative tumor blood loss but is also associated to an improvement on neurocognitive abilities compared to surgery alone. Importantly, complication rate is not increased. In the future, larger studies and perhaps a randomised control trial might be of value in corroborating these findings. Furthermore, the neurocognitive symptoms should be assessed in a standardised examination form, qualitative parameters such as bleeding tendency should be supplemented by quantifiable parameters, e.g., blood loss in ml.

First Measurement of High-Energy Reactor Antineutrinos at Daya Bay

This Letter reports the first measurement of high-energy reactor antineutrinos at Daya Bay, with nearly 9000 inverse beta decay candidates in the prompt energy region of 8-12 MeV observed over 1958 days of data collection. A multivariate analysis is used to separate 2500 signal events from background statistically. The hypothesis of no reactor antineutrinos with neutrino energy above 10 MeV is rejected with a significance of 6.2 standard deviations. A 29% antineutrino flux deficit in the prompt energy region of 8-11 MeV is observed compared to a recent model prediction. We provide the unfolded antineutrino spectrum above 7 MeV as a data-based reference for other experiments. This result provides the first direct observation of the production of antineutrinos from several high-Q_{β} isotopes in commercial reactors.

Joint Determination of Reactor Antineutrino Spectra from ^{235}U and ^{239}Pu Fission by Daya Bay and PROSPECT

A joint determination of the reactor antineutrino spectra resulting from the fission of ^{235}U and ^{239}Pu has been carried out by the Daya Bay and PROSPECT Collaborations. This Letter reports the level of consistency of ^{235}U spectrum measurements from the two experiments and presents new results from a joint analysis of both data sets. The measurements are found to be consistent. The combined analysis reduces the degeneracy between the dominant ^{235}U and ^{239}Pu isotopes and improves the uncertainty of the ^{235}U spectral shape to about 3%. The ^{235}U and ^{239}Pu antineutrino energy spectra are unfolded from the jointly deconvolved reactor spectra using the Wiener-SVD unfolding method, providing a data-based reference for other reactor antineutrino experiments and other applications. This is the first measurement of the ^{235}U and ^{239}Pu spectra based on the combination of experiments at low- and highly enriched uranium reactors.

Improved Constraints on Sterile Neutrino Mixing from Disappearance Searches in the MINOS, MINOS+, Daya Bay, and Bugey-3 Experiments

Searches for electron antineutrino, muon neutrino, and muon antineutrino disappearance driven by sterile neutrino mixing have been carried out by the Daya Bay and MINOS+ collaborations. This Letter presents the combined results of these searches, along with exclusion results from the Bugey-3 reactor experiment, framed in a minimally extended four-neutrino scenario. Significantly improved constraints on the θ_{μe} mixing angle are derived that constitute the most constraining limits to date over five orders of magnitude in the mass-squared splitting Δm_{41}^{2}, excluding the 90% C.L. sterile-neutrino parameter space allowed by the LSND and MiniBooNE observations at 90% CL_{s} for Δm_{41}^{2}<13  eV^{2}. Furthermore, the LSND and MiniBooNE 99% C.L. allowed regions are excluded at 99% CL_{s} for Δm_{41}^{2}<1.6 eV^{2}.

Extraction of the ^{235}U and ^{239}Pu Antineutrino Spectra at Daya Bay

This Letter reports the first extraction of individual antineutrino spectra from ^{235}U and ^{239}Pu fission and an improved measurement of the prompt energy spectrum of reactor antineutrinos at Daya Bay. The analysis uses 3.5×10^{6} inverse beta-decay candidates in four near antineutrino detectors in 1958 days. The individual antineutrino spectra of the two dominant isotopes, ^{235}U and ^{239}Pu, are extracted using the evolution of the prompt spectrum as a function of the isotope fission fractions. In the energy window of 4-6 MeV, a 7% (9%) excess of events is observed for the ^{235}U (^{239}Pu) spectrum compared with the normalized Huber-Mueller model prediction. The significance of discrepancy is 4.0σ for ^{235}U spectral shape compared with the Huber-Mueller model prediction. The shape of the measured inverse beta-decay prompt energy spectrum disagrees with the prediction of the Huber-Mueller model at 5.3σ. In the energy range of 4-6 MeV, a maximal local discrepancy of 6.3σ is observed.

Measurement of the Electron Antineutrino Oscillation with 1958 Days of Operation at Daya Bay

We report a measurement of electron antineutrino oscillation from the Daya Bay Reactor Neutrino Experiment with nearly 4 million reactor ν[over ¯]_{e} inverse β decay candidates observed over 1958 days of data collection. The installation of a flash analog-to-digital converter readout system and a special calibration campaign using different source enclosures reduce uncertainties in the absolute energy calibration to less than 0.5% for visible energies larger than 2 MeV. The uncertainty in the cosmogenic ^{9}Li and ^{8}He background is reduced from 45% to 30% in the near detectors. A detailed investigation of the spent nuclear fuel history improves its uncertainty from 100% to 30%. Analysis of the relative ν[over ¯]_{e} rates and energy spectra among detectors yields sin^{2}2θ_{13}=0.0856±0.0029 and Δm_{32}^{2}=(2.471_{-0.070}^{+0.068})×10^{-3}  eV^{2} assuming the normal hierarchy, and Δm_{32}^{2}=-(2.575_{-0.070}^{+0.068})×10^{-3}  eV^{2} assuming the inverted hierarchy.

A novel mouse model of rhabdomyosarcoma underscores the dichotomy of MDM2-ALT1 function in vivo

Alternative splicing of the oncogene murine double minute 2 (MDM2) is induced in response to genotoxic stress. MDM2-ALT1, the major splice variant generated, is known to activate the p53 pathway and impede full-length MDM2's negative regulation of p53. Despite this perceptible tumor-suppressive role, MDM2-ALT1 is also associated with several cancers. Furthermore, expression of MDM2-ALT1 has been observed in aggressive metastatic disease in pediatric rhabdomyosarcoma (RMS), irrespective of histological subtype. Therefore, we generated a transgenic MDM2-ALT1 mouse model that would allow us to investigate the effects of this splice variant on the progression of tumorigenesis. Here we show that when MDM2-ALT1 is ubiquitously expressed in p53 null mice it leads to increased incidence of spindle cell sarcomas, including RMS. Our data provide evidence that constitutive MDM2-ALT1 expression is itself an oncogenic lesion that aggravates the tumorigenesis induced by p53 loss. On the contrary, when MDM2-ALT1 is expressed solely in B-cells in the presence of homozygous wild-type p53 it leads to significantly increased lymphomagenesis (56%) when compared with control mice (27%). However, this phenotype is observable only at later stages in life (⩾18 months). Moreover, flow cytometric analyses for B-cell markers revealed an MDM2-ALT1-associated decrease in the B-cell population of the spleens of these animals. Our data suggest that the B-cell loss is p53 dependent and is a response mounted to persistent MDM2-ALT1 expression in a wild-type p53 background. Overall, our findings highlight the importance of an MDM2 splice variant as a critical modifier of both p53-dependent and -independent tumorigenesis, underscoring the complexity of MDM2 posttranscriptional regulation in cancer. Furthermore, MDM2-ALT1-expressing p53 null mice represent a novel mouse model of fusion-negative RMS.

Evolution of the Reactor Antineutrino Flux and Spectrum at Daya Bay

The Daya Bay experiment has observed correlations between reactor core fuel evolution and changes in the reactor antineutrino flux and energy spectrum. Four antineutrino detectors in two experimental halls were used to identify 2.2 million inverse beta decays (IBDs) over 1230 days spanning multiple fuel cycles for each of six 2.9 GW_{th} reactor cores at the Daya Bay and Ling Ao nuclear power plants. Using detector data spanning effective ^{239}Pu fission fractions F_{239} from 0.25 to 0.35, Daya Bay measures an average IBD yield σ[over ¯]_{f} of (5.90±0.13)×10^{-43}  cm^{2}/fission and a fuel-dependent variation in the IBD yield, dσ_{f}/dF_{239}, of (-1.86±0.18)×10^{-43}  cm^{2}/fission. This observation rejects the hypothesis of a constant antineutrino flux as a function of the ^{239}Pu fission fraction at 10 standard deviations. The variation in IBD yield is found to be energy dependent, rejecting the hypothesis of a constant antineutrino energy spectrum at 5.1 standard deviations. While measurements of the evolution in the IBD spectrum show general agreement with predictions from recent reactor models, the measured evolution in total IBD yield disagrees with recent predictions at 3.1σ. This discrepancy indicates that an overall deficit in the measured flux with respect to predictions does not result from equal fractional deficits from the primary fission isotopes ^{235}U, ^{239}Pu, ^{238}U, and ^{241}Pu. Based on measured IBD yield variations, yields of (6.17±0.17) and (4.27±0.26)×10^{-43}  cm^{2}/fission have been determined for the two dominant fission parent isotopes ^{235}U and ^{239}Pu. A 7.8% discrepancy between the observed and predicted ^{235}U yields suggests that this isotope may be the primary contributor to the reactor antineutrino anomaly.

Limits on Active to Sterile Neutrino Oscillations from Disappearance Searches in the MINOS, Daya Bay, and Bugey-3 Experiments

Searches for a light sterile neutrino have been performed independently by the MINOS and the Daya Bay experiments using the muon (anti)neutrino and electron antineutrino disappearance channels, respectively. In this Letter, results from both experiments are combined with those from the Bugey-3 reactor neutrino experiment to constrain oscillations into light sterile neutrinos. The three experiments are sensitive to complementary regions of parameter space, enabling the combined analysis to probe regions allowed by the Liquid Scintillator Neutrino Detector (LSND) and MiniBooNE experiments in a minimally extended four-neutrino flavor framework. Stringent limits on sin^{2}2θ_{μe} are set over 6 orders of magnitude in the sterile mass-squared splitting Δm_{41}^{2}. The sterile-neutrino mixing phase space allowed by the LSND and MiniBooNE experiments is excluded for Δm_{41}^{2}<0.8  eV^{2} at 95%  CL_{s}.

Improved Search for a Light Sterile Neutrino with the Full Configuration of the Daya Bay Experiment

This Letter reports an improved search for light sterile neutrino mixing in the electron antineutrino disappearance channel with the full configuration of the Daya Bay Reactor Neutrino Experiment. With an additional 404 days of data collected in eight antineutrino detectors, this search benefits from 3.6 times the statistics available to the previous publication, as well as from improvements in energy calibration and background reduction. A relative comparison of the rate and energy spectrum of reactor antineutrinos in the three experimental halls yields no evidence of sterile neutrino mixing in the 2×10^{-4}≲|Δm_{41}^{2}|≲0.3  eV^{2} mass range. The resulting limits on sin^{2}2θ_{14} are improved by approx imately a factor of 2 over previous results and constitute the most stringent constraints to date in the |Δm_{41}^{2}|≲0.2  eV^{2} region.

Quality Requirements for the early Fetal Ultrasound Assessment at 11-13+6 Weeks of Gestation (DEGUM Levels II and III)

The early fetal ultrasound assessment at 11 - 13(+6) weeks of gestation remains the cornerstone of care despite the progress in diagnosing fetal chromosomal defects using cell-free fetal DNA (cffDNA) from the maternal circulation. The measurement of nuchal translucency (NT) allows the risk calculation for the fetal trisomies 21, 18 and 13 but also gives information on those fetal chromosomal defects which are at present unable to be detected using cffDNA. Nuchal translucency is the only auditable parameter at 11 - 13(+6) weeks and gives thus information on the quality of the first trimester anomaly scan. In addition it gives indirect information on the risks for fetal defects and for cardiac anomalies. Also the chances for a healthy live baby can be estimated. As experience with first trimester anomaly scanning increases, and the resolution of the ultrasound equipment has increased substantially, more and more details of the fetal anatomy become accessible at the first trimester scan. Therefore fetal anatomical defects and complex anomalies have become amenable to examination in the first trimester. This guideline describes compulsory and optional parameters for investigation at the first trimester scan and outlines a structured method of examining a first trimester fetus at 11 - 13(+6) weeks of gestation.

Nonmagnetic band gap at the Dirac point of the magnetic topological insulator (Bi(1-x)Mn(x))2Se3

Magnetic doping is expected to open a band gap at the Dirac point of topological insulators by breaking time-reversal symmetry and to enable novel topological phases. Epitaxial (Bi_1−xMn_x)₂Se₃ is a prototypical magnetic topological insulator with a pronounced surface band gap of ∼100 meV. We show that this gap is neither due to ferromagnetic order in the bulk or at the surface nor to the local magnetic moment of the Mn, making the system unsuitable for realizing the novel phases. We further show that Mn doping does not affect the inverted bulk band gap and the system remains topologically nontrivial. We suggest that strong resonant scattering processes cause the gap at the Dirac point and support this by the observation of in-gap states using resonant photoemission. Our findings establish a mechanism for gap opening in topological surface states which challenges the currently known conditions for topological protection.

Doping a topological insulator with magnetic impurities is expected to induce ferromagnetism and open a band gap in its surface states. Here, the authors study Mn-doped Bi₂Se₃, finding a mechanism for band gap opening in topologically-protected surface states which is not of magnetic origin.

Measurement of the Reactor Antineutrino Flux and Spectrum at Daya Bay

This Letter reports a measurement of the flux and energy spectrum of electron antineutrinos from six 2.9 GWth nuclear reactors with six detectors deployed in two near (effective baselines 512 and 561 m) and one far (1579 m) underground experimental halls in the Daya Bay experiment. Using 217 days of data, 296 721 and 41 589 inverse β decay (IBD) candidates were detected in the near and far halls, respectively. The measured IBD yield is (1.55±0.04) ×10(-18)  cm(2) GW(-1) day(-1) or (5.92±0.14) ×10(-43)  cm(2) fission(-1). This flux measurement is consistent with previous short-baseline reactor antineutrino experiments and is 0.946±0.022 (0.991±0.023) relative to the flux predicted with the Huber-Mueller (ILL-Vogel) fissile antineutrino model. The measured IBD positron energy spectrum deviates from both spectral predictions by more than 2σ over the full energy range with a local significance of up to ∼4σ between 4-6 MeV. A reactor antineutrino spectrum of IBD reactions is extracted from the measured positron energy spectrum for model-independent predictions.

Amyloid-PET predicts inhibition of de novo plaque formation upon chronic γ-secretase modulator treatment

In a positron-emission tomography (PET) study with the β-amyloid (Aβ) tracer [(18)F]-florbetaben, we previously showed that Aβ deposition in transgenic mice expressing Swedish mutant APP (APP-Swe) mice can be tracked in vivo. γ-Secretase modulators (GSMs) are promising therapeutic agents by reducing generation of the aggregation prone Aβ42 species without blocking general γ-secretase activity. We now aimed to investigate the effects of a novel GSM [8-(4-Fluoro-phenyl)-[1,2,4]triazolo[1,5-a]pyridin-2-yl]-[1-(3-methyl-[1,2,4]thiadiazol-5-yl)-piperidin-4-yl]-amine (RO5506284) displaying high potency in vitro and in vivo on amyloid plaque burden and used longitudinal Aβ-microPET to trace individual animals. Female transgenic (TG) APP-Swe mice aged 12 months (m) were assigned to vehicle (TG-VEH, n=12) and treatment groups (TG-GSM, n=12), which received daily RO5506284 (30 mg kg(-1)) treatment for 6 months. A total of 131 Aβ-PET recordings were acquired at baseline (12 months), follow-up 1 (16 months) and follow-up 2 (18 months, termination scan), whereupon histological and biochemical analyses of Aβ were performed. We analyzed the PET data as VOI-based cortical standard-uptake-value ratios (SUVR), using cerebellum as reference region. Individual plaque load assessed by PET remained nearly constant in the TG-GSM group during 6 months of RO5506284 treatment, whereas it increased progressively in the TG-VEH group. Baseline SUVR in TG-GSM mice correlated with Δ%-SUVR, indicating individual response prediction. Insoluble Aβ42 was reduced by 56% in the TG-GSM versus the TG-VEH group relative to the individual baseline plaque load estimates. Furthermore, plaque size histograms showed differing distribution between groups of TG mice, with fewer small plaques in TG-GSM animals. Taken together, in the first Aβ-PET study monitoring prolonged treatment with a potent GSM in an AD mouse model, we found clear attenuation of de novo amyloidogenesis. Moreover, longitudinal PET allows non-invasive assessment of individual plaque-load kinetics, thereby accommodating inter-animal variations.

New measurement of antineutrino oscillation with the full detector configuration at Daya Bay

We report a new measurement of electron antineutrino disappearance using the fully constructed Daya Bay Reactor Neutrino Experiment. The final two of eight antineutrino detectors were installed in the summer of 2012. Including the 404 days of data collected from October 2012 to November 2013 resulted in a total exposure of 6.9×10^{5} GW_{th}  ton days, a 3.6 times increase over our previous results. Improvements in energy calibration limited variations between detectors to 0.2%. Removal of six ^{241}Am-^{13}C radioactive calibration sources reduced the background by a factor of 2 for the detectors in the experimental hall furthest from the reactors. Direct prediction of the antineutrino signal in the far detectors based on the measurements in the near detectors explicitly minimized the dependence of the measurement on models of reactor antineutrino emission. The uncertainties in our estimates of sin^{2}2θ_{13} and |Δm_{ee}^{2}| were halved as a result of these improvements. An analysis of the relative antineutrino rates and energy spectra between detectors gave sin^{2}2θ_{13}=0.084±0.005 and |Δm_{ee}^{2}|=(2.42±0.11)×10^{-3}  eV^{2} in the three-neutrino framework.

Understanding intramembrane proteolysis: from protein dynamics to reaction kinetics

Intramembrane proteolysis - cleavage of proteins within the plane of a membrane - is a widespread phenomenon that can contribute to the functional activation of substrates and is involved in several diseases. Although different families of intramembrane proteases have been discovered and characterized, we currently do not know how these enzymes discriminate between substrates and non-substrates, how site-specific cleavage is achieved, or which factors determine the rate of proteolysis. Focusing on γ-secretase and rhomboid proteases, we argue that answers to these questions may emerge from connecting experimental readouts, such as reaction kinetics and the determination of cleavage sites, to the structures and the conformational dynamics of substrates and enzymes.

Neural effects of cognitive-behavioural therapy on dysfunctional attitudes in depression

BACKGROUND

Dysfunctional attitudes are a feature of depression that has been correlated with receptor binding abnormalities in limbic and cortical regions. We sought to investigate the functional neuroanatomy of dysfunctional attitudes in major depressive disorder (MDD) and the effects of treatment with cognitive-behavioural therapy (CBT).

METHOD

Participants were 16 patients with unipolar depression in an acute depressive episode (mean age 40.0 years) and 16 matched healthy controls (mean age 39.9 years). Patients were medication free and received a course of treatment with CBT. All participants underwent functional magnetic resonance imaging (fMRI) scans at baseline and at week 16, prior to the initiation of therapy and following the course of CBT for patients. During each fMRI scan, participants indicated their attributions to statements from a modified Dysfunctional Attitudes Scale (mDAS-48).

RESULTS

MDD patients in an acute depressive episode endorsed a greater number of extreme responses to DAS statements, which normalized following CBT treatment. Extreme attributions were associated with greater activation in the left hippocampal region, inferior parietal lobe and precuneus in MDD patients as compared with healthy controls as a main effect of group. An interaction effect was found in the left parahippocampal region, which showed less attenuation in MDD patients at the follow-up scan relative to healthy controls.

CONCLUSIONS

Attenuation of activity in the parahippocampal region may be indicative of an improvement in dysfunctional thinking following CBT treatment in depression, while persistent engagement of regions involved in attentional processing and memory retrieval with extreme attributions reflects a trait feature of depression.

[Management of postpartum hemorrhage (PPH): algorithm of the interdisciplinary D-A-CH consensus group PPH (Germany - Austria - Switzerland)]

Postpartum hemorrhage (PPH) is one of the main causes of maternal deaths even in industrialized countries. It represents an emergency situation which necessitates a rapid decision and in particular an exact diagnosis and root cause analysis in order to initiate the correct therapeutic measures in an interdisciplinary cooperation. In addition to established guidelines, the benefits of standardized therapy algorithms have been demonstrated. A therapy algorithm for the obstetric emergency of postpartum hemorrhage in the German language is not yet available. The establishment of an international (Germany, Austria and Switzerland D-A-CH) "treatment algorithm for postpartum hemorrhage" was an interdisciplinary project based on the guidelines of the corresponding specialist societies (anesthesia and intensive care medicine and obstetrics) in the three countries as well as comparable international algorithms for therapy of PPH.The obstetrics and anesthesiology personnel must possess sufficient expertise for emergency situations despite lower case numbers. The rarity of occurrence for individual patients and the life-threatening situation necessitate a structured approach according to predetermined treatment algorithms. This can then be carried out according to the established algorithm. Furthermore, this algorithm presents the opportunity to train for emergency situations in an interdisciplinary team.

Search for a light sterile neutrino at Daya Bay

A search for light sterile neutrino mixing was performed with the first 217 days of data from the Daya Bay Reactor Antineutrino Experiment. The experiment's unique configuration of multiple baselines from six 2.9 GW(th) nuclear reactors to six antineutrino detectors deployed in two near (effective baselines 512 m and 561 m) and one far (1579 m) underground experimental halls makes it possible to test for oscillations to a fourth (sterile) neutrino in the 10(-3) eV(2)<|Δm(41)(2) |< 0.3 eV(2) range. The relative spectral distortion due to the disappearance of electron antineutrinos was found to be consistent with that of the three-flavor oscillation model. The derived limits on sin(2) 2θ(14) cover the 10(-3) eV(2) ≲ |Δm(41)(2)| ≲ 0.1 eV(2) region, which was largely unexplored.

Spectral measurement of electron antineutrino oscillation amplitude and frequency at Daya Bay

A measurement of the energy dependence of antineutrino disappearance at the Daya Bay reactor neutrino experiment is reported. Electron antineutrinos (ν¯(e)) from six 2.9  GW(th) reactors were detected with six detectors deployed in two near (effective baselines 512 and 561 m) and one far (1579 m) underground experimental halls. Using 217 days of data, 41 589 (203 809 and 92 912) antineutrino candidates were detected in the far hall (near halls). An improved measurement of the oscillation amplitude sin(2)2θ(13)=0.090(-0.009)(+0.008) and the first direct measurement of the ν¯(e) mass-squared difference |Δm(ee)2|=(2.59(-0.20)(+0.19))×10(-3)  eV2 is obtained using the observed ν¯(e) rates and energy spectra in a three-neutrino framework. This value of |Δm(ee)2| is consistent with |Δm(μμ)2| measured by muon neutrino disappearance, supporting the three-flavor oscillation model.

Design of an implantable seismic sensor placed on the ossicular chain

This paper presents a design guideline for matching a fully implantable middle ear microphone with the physiology of human hearing. The guideline defines the first natural frequency of a seismic sensor placed at the tip of the manubrium mallei with respect to the frequency-dependence hearing of the human ear as well as the deflection of the ossicular chain. A transducer designed in compliance with the guideline presented reduces the range of the output signal while preserving all information obtained by the ossicular chain. On top of a output signal compression, static deflections, which can mask the tiny motions of the ossicles, are reduced. For guideline verification, a microelectromechanical system (MEMS) based on silicon on insulator technology was produced and tested. This prototype is capable of resolving 0.4 pm/Hz with a custom made read-out circuit. For a bandwidth of 0.1 kHz, this deflection is comparable with the lower threshold of speech (≈ 40 phon).

Adnexal Torsion in Pregnancy after Assisted Reproduction - Case Study and Review of the Literature

Purpose: Aim of the study was to investigate the incidence, progress, management and outcome of adnexal torsion after controlled ovarian hyperstimulation in embryo transfer cycles. Materials and Method: A retrospective analysis was done of 1007 patients of a private IVF centre. The literature on adnexal torsion is reviewed. Results: In the literature, the incidence of adnexal torsion after assisted reproductive technologies (ART) is given as around 0.2 %. A significant increase of up to 33 % has been reported for cases with additional ovarian hyperstimulation syndrome (OHSS) and in pregnant women. In our retrospective analysis of 1007 women (incidence 0.46 %) with 1411 fresh embryo transfer cycles, we found an incidence of 0.35 % per embryo transfer. All adnexal torsions were treated by laparoscopic derotation to preserve fertility. All 5 cases with torsion were pregnant, 2 patients had mild OHSS. We recorded 3 term deliveries, 1 induced abortion for sirenomelia, and 1 missed abortion. Conclusion: Adnexal torsion must be kept in mind after hyperstimulation and embryo transfer, especially when pregnancy or OHSS is also present. With early diagnosis, it should be possible to preserve fertility using laparoscopic derotation.

Observation of electron-antineutrino disappearance at Daya Bay

The Daya Bay Reactor Neutrino Experiment has measured a nonzero value for the neutrino mixing angle θ(13) with a significance of 5.2 standard deviations. Antineutrinos from six 2.9 GWth reactors were detected in six antineutrino detectors deployed in two near (flux-weighted baseline 470 m and 576 m) and one far (1648 m) underground experimental halls. With a 43,000 ton-GWth-day live-time exposure in 55 days, 10,416 (80,376) electron-antineutrino candidates were detected at the far hall (near halls). The ratio of the observed to expected number of antineutrinos at the far hall is R=0.940±0.011(stat.)±0.004(syst.). A rate-only analysis finds sin(2)2θ(13)=0.092±0.016(stat.)±0.005(syst.) in a three-neutrino framework.

Posttraumatic stress disorder in children and adolescents: a review of psychopharmacological treatment

PTSD in children and adolescents differs from the adult disease. Therapeutic approaches involve both psychotherapy and psychopharmacotherapy.

OBJECTIVES

The current paper aims at reviewing studies on psychopharmacological treatment of childhood and adolescent PTSD. Additionally, developmental frameworks for PTSD diagnosis and research along with an experimental model of quenching and kindling in the context of stress exposure are presented. We conducted an extensive literature search of reviews on psychopharmacotherapy as well as studies on psychopharmacological treatment for PTSD among children and adolescents. We used the database PubMed and focused on the time period of the last 10 years up to January 2009. Pertinent earlier papers were also included.There are a limited number of studies specifically assessing the psychopharmacological treatment of PTSD in children and adolescents. The vast majority of them lack verification in RCTs. Only the use of imipramine, divalproex sodium and sertraline were already evaluated in RCTs. Future studies should take into account developmental approaches to the diagnosis and treatment of PTSD in children and adolescents. In this context, different underlying neurobiological patterns, which are reflected in distinct clinical symptomatology, require a precise investigation and a symptom-orientated psychopharmacological approach.