Direct Chargino-Neutralino Production at the LHC: Interpreting the Exclusion Limits in the Complex MSSM

We re-assess the exclusion limits on the parameters describing the supersymmetric (SUSY) electroweak sector of the MSSM obtained from the search for direct chargino-neutralino production at the LHC. We start from published limits obtained in simplified models, where for the case of heavy sleptons the relevant branching ratio, BR(neu2->neu1 Z), is set to one. We show how the decay mode neu2->neu1 h, which cannot be neglected in any realistic model once kinematically allowed, substantially reduces the excluded parameter region. We analyze the dependence of the excluded regions on the phase of the gaugino soft SUSY-breaking mass parameter, M_1, on the mass of the light scalar tau, on tb as well as on the squark and slepton mass scales. Large reductions in the ranges of parameters excluded can be observed in all scenarios. The branching ratios of charginos and neutralinos are evaluated using a full NLO calculation for the complex MSSM. The size of the effects of the NLO calculation on the exclusion bounds is investigated. We furthermore assess the potential reach of the experimental analyses after collecting 100/fb at the LHC running at 13 TeV.Comment: 34 pages, 12 figures. Minor changes, matches published versio

Relic density of wino-like dark matter in the MSSM

The relic density of TeV-scale wino-like neutralino dark matter in the MSSM is subject to potentially large corrections as a result of the Sommerfeld effect. A recently developed framework enables us to calculate the Sommerfeld-enhanced relic density in general MSSM scenarios, properly treating mixed states and multiple co-annihilating channels as well as including off-diagonal contributions. Using this framework, including on-shell one-loop mass splittings and running couplings and taking into account the latest experimental constraints, we perform a thorough study of the regions of parameter space surrounding the well known pure-wino scenario: namely the effect of sfermion masses being non-decoupled and of allowing non-negligible Higgsino or bino components in the lightest neutralino. We further perform an investigation into the effect of thermal corrections and show that these can safely be neglected. The results reveal a number of phenomenologically interesting but so far unexplored regions where the Sommerfeld effect is sizeable. We find, in particular, that the relic density can agree with experiment for dominantly wino neutralino dark matter with masses ranging from 1.7 to beyond 4 TeV. In light of these results the bounds from Indirect Detection on wino-like dark matter should be revisited.Comment: 49 pages, 15 figure

Neutralino Decays in the Complex MSSM at One-Loop: a Comparison of On-Shell Renormalization Schemes

We evaluate two-body decay modes of neutralinos in the Minimal Supersymmetric Standard Model with complex parameters (cMSSM). Assuming heavy scalar quarks we take into account all two-body decay channels involving charginos, neutralinos, (scalar) leptons, Higgs bosons and Standard Model gauge bosons. The evaluation of the decay widths is based on a full one-loop calculation including hard and soft QED radiation. Of particular phenomenological interest are decays involving the Lightest Supersymmetric Particle (LSP), i.e. the lightest neutralino, or a neutral or charged Higgs boson. For the chargino/neutralino sector we employ two different renormalization schemes, which differ in the treatment of the complex phases. In the numerical analysis we concentrate on the decay of the heaviest neutralino and show the results in the two different schemes. The higher-order corrections of the heaviest neutralino decay widths involving the LSP can easily reach a level of about 10-15%, while the corrections to the decays to Higgs bosons are up to 20-30%, translating into corrections of similar size in the respective branching ratios. The difference between the two schemes, indicating the size of unknown two-loop corrections, is less than order(0.1%). These corrections are important for the correct interpretation of LSP and Higgs production at the LHC and at a future linear e+e- collider. The results will be implemented into the Fortran code FeynHiggs.Comment: 49 pages, 27 figures, typos corrected. arXiv admin note: substantial text overlap with arXiv:1112.0760, arXiv:1111.7289, arXiv:1204.400

Monojet searches for momentum-dependent dark matter interactions

We consider minimal dark matter scenarios featuring momentum-dependent couplings of the dark sector to the Standard Model. We derive constraints from existing LHC searches in the monojet channel, estimate the future LHC sensitivity for an integrated luminosity of 300 fb−1, and compare with models exhibiting conventional momentum-independent interactions with the dark sector. In addition to being well motivated by (composite) pseudo-Goldstone dark matter scenarios, momentum-dependent couplings are interesting as they weaken direct detection constraints. For a specific dark matter mass, the LHC turns out to be sensitive to smaller signal cross-sections in the momentum-dependent case, by virtue of the harder jet transverse-momentum distribution

Surgical Interventions and the Use of Device-Aided Therapy for the Treatment of Fecal Incontinence and Defecatory Disorders

The purpose of this clinical practice update expert review is to describe the key principles in the use of surgical interventions and device-aided therapy for managing fecal incontinence (FI) and defecatory disorders. The best practices outlined in this review are based on relevant publications, including systematic reviews and expert opinion (when applicable). Best Practice Advice 1: A stepwise approach should be followed for management of FI. Conservative therapies (diet, fluids, techniques to improve evacuation, a bowel training program, management of diarrhea and constipation with diet and medications if necessary) will benefit approximately 25% of patients and should be tried first. Best Practice Advice 2: Pelvic floor retraining with biofeedback therapy is recommended for patients with FI who do not respond to the conservative measures indicated above. Best Practice Advice 3: Perianal bulking agents such as intra-anal injection of dextranomer may be considered when conservative measures and biofeedback therapy fail. Best Practice Advice 4: Sacral nerve stimulation should be considered for patients with moderate or severe FI in whom symptoms have not responded after a 3-month or longer trial of conservative measures and biofeedback therapy and who do not have contraindications to these procedures. Best Practice Advice 5: Until further evidence is available, percutaneous tibial nerve stimulation should not be used for managing FI in clinical practice. Best Practice Advice 6: Barrier devices should be offered to patients who have failed conservative or surgical therapy, or in those who have failed conservative therapy who do not want or are not eligible for more invasive interventions. Best Practice Advice 7: Anal sphincter repair (sphincteroplasty) should be considered in postpartum women with FI and in patients with recent sphincter injuries. In patients who present later with symptoms of FI unresponsive to conservative and biofeedback therapy and evidence of sphincter damage, sphincteroplasty may be considered when perianal bulking injection and sacral nerve stimulation are not available or have proven unsuccessful. Best Practice Advice 8: The artificial anal sphincter, dynamic graciloplasty, may be considered for patients with medically refractory severe FI who have failed treatment or are not candidates for barrier devices, sacral nerve stimulation, perianal bulking injection, sphincteroplasty and a colostomy. Best Practice Advice 9: Major anatomic defects (eg, rectovaginal fistula, full-thickness rectal prolapse, fistula in ano, or cloaca-like deformity) should be rectified with surgery. Best Practice Advice 10: A colostomy should be considered in patients with severe FI who have failed conservative treatment and have failed or are not candidates for barrier devices, minimally invasive surgical interventions, and sphincteroplasty. Best Practice Advice 11: A magnetic anal sphincter device may be considered for patients with medically refractory severe FI who have failed or are not candidates for barrier devices, perianal bulking injection, sacral nerve stimulation, sphincteroplasty, or a colostomy. Data regarding efficacy are limited and 40% of patients had moderate or severe complications. Best Practice Advice 12: For defecatory disorders, biofeedback therapy is the treatment of choice. Best Practice Advice 13: Based on limited evidence, sacral nerve stimulation should not be used for managing defecatory disorders in clinical practice. Best Practice Advice 14: Anterograde colonic enemas are not effective in the long term for management of defecatory disorders. Best Practice Advice 15: The stapled transanal rectal resection and related procedures should not be routinely performed for correction of structural abnormalities in patients with defecatory disorders

Confocal Laser Endomicroscopy in the Assessment of Intestinal Permeability in Acute and Chronic Pancreatitis

Abstract Background: The function of the gastrointestinal tract in monitoring and sealing the host interior from toxins, antigens and microbes, is termed the gut barrier. Disruptions in the gut barrier result in an increase in intestinal permeability (IP). Evidence suggests that the intestinal permeability barrier becomes compromised in acute pancreatitis (AP), chronic liver disease (CLD) and to a limited degree in chronic pancreatitis (CP). In acute pancreatitis, changes correlate with disease severity, multi-organ failure, mortality and outcome. Bacterial translocation and dysbiosis along with immunological responses have also been associated with changes in gut permeability. Confocal laser endomicroscopy (CLE) is a novel tool that has been used to investigate intestinal permeability in other gastrointestinal disease. Aims: To determine whether CLE can be used to assess intestinal permeability, bacterial translocation and endotoxaemia in patients with chronic pancreatitis, chronic liver disease and acute pancreatitis. To assess the responses of immunology and infection in patients with acute pancreatitis whilst also assessing changes related to increasing severity of disease in acute pancreatitis. Methods: 182 patients were recruited: 54 AP (Determinant Based Classification); 47 CP (surgically or conservatively managed); 33 CLD and 48 non-ulcer dyspepsia, rendering 13 healthy controls. Blood was sampled and duodenal fluid aspirated for culture. CLE was performed in consenting patients and fluorescein leakage scored. Endotoxin antibodies, cytokine concentrations and lactulose mannitol ratios were measured; Diamine oxidase (DAO) concentrations were assayed in AP patients undergoing CLE. Results: Fluorescein leakage and lactulose mannitol ratios were significantly higher in patients with AP (p=0.0346 and p=0.046 respectively) and surgically managed CP (p=0.032, p=0.030) compared to healthy controls. Patients with AP more frequently showed positive duodenal bacterial cultures than controls (p=0.004); positive duodenal cultures were associated with fluorescein leakage (p=0.035). Plasma endotoxin antibody concentrations were decreased in AP compared to controls. Multiple cytokines showed significantly increased concentrations in severe AP. DAO concentrations were significantly increased in AP patients who showed fluorescein leakage at CLE (p=0.035). Conclusion: CLE identified increased IP in AP and surgically managed CP, associated with endotoxaemia, increased serum cytokines and DAO, with most marked changes in severe AP. The association of fluorescein leakage with duodenal bacterial proliferation in AP indicates major gut dysfunction that may account for bacterial translocation via epithelial gaps, contributing to AP severity. Endotoxaemia, positive duodenal bacterial cultures, and increased serum concentrations of several cytokines were associated with increasing severity of AP. The increase in positive duodenal bacterial cultures in patients who also demonstrated fluorescein leakage at CLE supports a hypothesis of bacterial translocation, suggesting that the gastrointestinal barrier is altered in AP. Evidence for increased IP was also observed in surgically managed CP patients, suggesting that the gut barrier may also be compromised in some CP patients