The Isotropic Radio Background and Annihilating Dark Matter

Observations by ARCADE-2 and other telescopes sensitive to low frequency radiation have revealed the presence of an isotropic radio background with a hard spectral index. The intensity of this observed background is found to exceed the flux predicted from astrophysical sources by a factor of approximately 5-6. In this article, we consider the possibility that annihilating dark matter particles provide the primary contribution to the observed isotropic radio background through the emission of synchrotron radiation from electron and positron annihilation products. For reasonable estimates of the magnetic fields present in clusters and galaxies, we find that dark matter could potentially account for the observed radio excess, but only if it annihilates mostly to electrons and/or muons, and only if it possesses a mass in the range of approximately 5-50 GeV. For such models, the annihilation cross section required to normalize the synchrotron signal to the observed excess is sigma v ~ (0.4-30) x 10^-26 cm^3/s, similar to the value predicted for a simple thermal relic (sigma v ~ 3 x 10^-26 cm^3/s). We find that in any scenario in which dark matter annihilations are responsible for the observed excess radio emission, a significant fraction of the isotropic gamma ray background observed by Fermi must result from dark matter as well.Comment: 11 pages, 6 figure

Characteristics of Ten Tropical Hardwoods from Certified Forests in Bolivia. Part II. Natural Durability to Decay Fungi

The natural durability of 10 lesser known, commercially available Bolivian hardwoods to decay fungi was evaluated using a modified ASTM soil-block analysis for 12 weeks. The blocks were then retested for an additional 12 weeks to determine their level of decay resistance, as determined by percentage of weight loss. Astronium urundeuva, Caesalpinia cf. pluviosa, Schinopsis quebrachocolorado, and Tabebuia sp. (Iapacho group) were found to be highly resistant to decay; Amburana cearensis, Anadenanthera colubrina (syn: A. macrocarpa), Aspidosperma cylindrocarpon, Diplotropis purpurea, and Guibourtia chodatiana, resistant to decay; and Phyllostylon rhamnoides, moderately resistant to decay. We conclude that an extended soil-bottle test is an effective tool for assessing the level of natural durability of these and other tropical species

Nonlinear cochlear dynamics

In this report we examine a model for human hearing. The unknown parameters in the model are estimated using experimental data and standard optimisation methods as described in the text. Additionally, we suggest possible improvements to the model as well as proposing a method to use the current model in locating which frequencies are aected in a damaged ear. Keywords: cochlear model, delay dierential equation, parameter es-timation, hearing los

The Validity of Patient-Reported Short-Term Complications following Total Hip and Knee Arthroplasty

Introduction: Given the lack of national data on outcomes of on patients who undergo total joint arthroplasty (TJA) and the limitations of hospital databases to capture information on patients who seek post-TJA care elsewhere, there is growing interest in using patient self-report to identify possible complications following surgery. We examined the concordance between patients self-report of potential short-term complications with review of available medical records as well as the location of the reported post-operative care. Material & Methods: Patients undergoing primary hip or knee arthroplasty from 7/1/11 through 12/3/12 participating in a tertiary care center were identified. Patients completed a 6-month post-operative survey regarding needing evaluation at an emergency department, day surgery or hospitalization for possible medical or mechanical complications and the location of care. We reviewed available inpatient and outpatient medical records to identify the location of postoperative care as well as the validity of patient self-report (sensitivity, specificity, positive predictive values and negative predictive values). Results: There were 413 patients who had 431 surgeries and completed the 6-month questionnaire. Patients reported 40 medical encounters including emergency department, day surgery or inpatient care resulting in a 9% reported complication rate, of which 20% occurred at outside hospitals Overall patient self-report of emergency department, day surgery and inpatient care for possible complications was both sensitive (82%) and specific (100%). The positive predictive value was 100% and negative predictive value 98%. Conclusion: Given the prevalence of events requiring care at outlying hospitals and the accuracy of self-report, methods that directly engage patients can augment current surveillance procedures

efficacy of botulinum toxin type a treatment of functional impairment of degenerative hip joint preliminary results

Objective: the aim of this study was to investigate the effect of botulinum toxin type a injection into the adductor muscles in reducing pain and improving joint mobility and quality of life in patients affected by hip osteoarthritis. Methods: a total of 39 outpatients, mean age 68 years (age range 41–82 years), were evaluated using the harris hip Score to test hip function, a visual analogue scale to measure pain intensity and the Short Form 36 (SF-36) questionnaire to assess patient well-being and quality of life at baseline, 2, 4 and 12 weeks after treatment with botulinum toxin type a. a total of 400 u of botulinum toxin type a (Dysport) was injected into the adductor longus muscle and the adductor magnus muscle. Results: The Harris Hip Score increased significantly after 2, 4 and 12 weeks (df 3, χ 2 = 45.1; p < 0.0001). A significant decrease in pain intensity was detected at all the follow-up visits, after 2, 4 and 12 weeks (df 3; χ 2 = 27.8; p < 0.001). the SF-36 score was significantly higher 4 and 12 weeks after treatment. At each evaluation visit a significant correlation was detected between decreased pain and improved hip mobility. Conclusion: Botulinum toxin type a induced a reduction in pain, indicating that this might be an innovative, less invasive treatment in patients affected by severe hip osteoarthritis, with remarkable effects on the clinical management of this disease

Efficacy of botulinum toxin type A treatment of functional impairment of degenerative hip joint: Preliminary results

Objective: the aim of this study was to investigate the effect of botulinum toxin type a injection into the adductor muscles in reducing pain and improving joint mobility and quality of life in patients affected by hip osteoarthritis. Methods: a total of 39 outpatients, mean age 68 years (age range 41–82 years), were evaluated using the harris hip Score to test hip function, a visual analogue scale to measure pain intensity and the Short Form 36 (SF-36) questionnaire to assess patient well-being and quality of life at baseline, 2, 4 and 12 weeks after treatment with botulinum toxin type a. a total of 400 u of botulinum toxin type a (Dysport) was injected into the adductor longus muscle and the adductor magnus muscle. Results: The Harris Hip Score increased significantly after 2, 4 and 12 weeks (df 3, χ 2 = 45.1; p < 0.0001). A significant decrease in pain intensity was detected at all the follow-up visits, after 2, 4 and 12 weeks (df 3; χ 2 = 27.8; p < 0.001). the SF-36 score was significantly higher 4 and 12 weeks after treatment. At each evaluation visit a significant correlation was detected between decreased pain and improved hip mobility. Conclusion: Botulinum toxin type a induced a reduction in pain, indicating that this might be an innovative, less invasive treatment in patients affected by severe hip osteoarthritis, with remarkable effects on the clinical management of this disease

Location of All-cause 30-day Readmission Following Total Joint Replacement: Surgical Hospital Versus Outside Hospital

Background: Evaluating posthospital complications and hospital readmissions in the United States is limited under the current system. This is due to an inability to quantify posthospital care delivered to patients at locations other than the surgical hospital. In order to circumvent this issue, information can be sought directly from patients about posthospital health care utilization. This approach provides a more complete record in comparison with methods that evaluate complications treated only at the surgical hospital. Methods: Participants undergoing total joint replacement (TJR) between 5/10/11 and 5/17/11 were identified from the Function and Outcomes Research in Comparative Effectiveness Registry (FORCE-TJR) cohort. The cohort is a nationally representative sample of TJR patients undergoing total knee replacement and total hip replacement. Patients are asked to self-report complications on the six-month follow-up questionnaire. The questionnaire specifically inquires about any emergency department visit, outpatient surgery, or hospital admission that occurred within six months of the total joint replacement surgery. For each positive report of postoperative complication, the pertinent medical records are retrieved and reviewed and discharge diagnoses are used to identify whether the complication is a surgical site symptom or a medical complication. The location of the care is identified as the surgical hospital or an outside hospital. We report on the location of all readmissions within 30 days of discharge from the initial TJR surgery. Results: In total, our sample yielded 112 validated patient-reported readmissions following TJR. Of these readmissions, 75% were treated at the surgical hospital and 25% were treated at an outside hospital. Patients receiving care at the surgical hospital were similar in terms of demographics compared with those seeking care at an outside hospital in terms of mean age (66.7 years vs. 66.9 years, p=0.92), and gender (67.9% male vs. 63.1% male, p=0.65). Additionally, the mean number of days since discharge was similar (16.7 days vs. 15.1 days, p = 0.45) among patients treated at the surgical hospital compared with those treated at an outside hospital. Discharge diagnoses varied by the location of care. At the surgical hospital, discharge diagnoses identified surgical site symptoms as the cause of 36.9% of admissions and medical conditions as the cause of 63.1% of admissions. When compared with discharge diagnoses at outside hospitals, surgical site symptoms accounted for 17.9% of admissions and medical conditions for 82.1% (p=0.067). Conclusion: Public reporting of all post-TJR discharge complications is currently used to compare quality of care between hospitals. However, our study demonstrates that hospitals and surgeons may underestimate their complication rates by 25%. This suggests that novel approaches, such as direct to patient contact, are needed to minimize missing post-hospital event data

Filter-based stochastic algorithm for global optimization

We propose the general Filter-based Stochastic Algorithm (FbSA) for the global optimization of nonconvex and nonsmooth constrained problems. Under certain conditions on the probability distributions that generate the sample points, almost sure convergence is proved. In order to optimize problems with computationally expensive black-box objective functions, we develop the FbSA-RBF algorithm based on the general FbSA and assisted by Radial Basis Function (RBF) surrogate models to approximate the objective function. At each iteration, the resulting algorithm constructs/updates a surrogate model of the objective function and generates trial points using a dynamic coordinate search strategy similar to the one used in the Dynamically Dimensioned Search method. To identify a promising best trial point, a non-dominance concept based on the values of the surrogate model and the constraint violation at the trial points is used. Theoretical results concerning the sufficient conditions for the almost surely convergence of the algorithm are presented. Preliminary numerical experiments show that the FbSA-RBF is competitive when compared with other known methods in the literature.The authors are grateful to the anonymous referees for their fruitful comments and suggestions.The first and second authors were partially supported by Brazilian Funds through CAPES andCNPq by Grants PDSE 99999.009400/2014-01 and 309303/2017-6. The research of the thirdand fourth authors were partially financed by Portuguese Funds through FCT (Fundação para Ciência e Tecnologia) within the Projects UIDB/00013/2020 and UIDP/00013/2020 of CMAT-UM and UIDB/00319/2020

Montagem do sistema para dosimetria de nêutrons com detectores de bolhas

São descritos a montagem e o procedimento desenvolvido para a aquisição e analise de imagens obtidas com os novos detectores de bolha BDS, para dosimetria de nêutrons ou nas medições de fluência e distribuição de energia de nêutrons de uma instalação nuclear