Model reduction of dynamical systems with a novel data-driven approach: The RC-HAVOK algorithm.

This paper introduces a novel data-driven approximation method for the Koopman operator, called the RC-HAVOK algorithm. The RC-HAVOK algorithm combines Reservoir Computing (RC) and the Hankel Alternative View of Koopman (HAVOK) to reduce the size of the linear Koopman operator with a lower error rate. The accuracy and feasibility of the RC-HAVOK algorithm are assessed on Lorenz-like systems and dynamical systems with various nonlinearities, including the quadratic and cubic nonlinearities, hyperbolic tangent function, and piece-wise linear function. Implementation results reveal that the proposed model outperforms a range of other data-driven model identification algorithms, particularly when applied to commonly used Lorenz time series data.

Development and performance evaluation of a novel scintillation-based active shielding gamma probe.

The gamma probe is a commonly used detector for localizing sentinel lymph nodes after the injection of radiopharmaceuticals. In recent years, studies have focused on improving the features of gamma probes to achieve more consistent localization of the radiotracer uptake. As part of this effort, a novel gamma probe prototype based on an active shielding was developed, and its characteristics, including sensitivity, resolution and shielding effectiveness, were determined. The prototype integrates trapezoidal-shaped bismuth germanate (BGO) array coupled with a silicon photomultiplier (SiPM) array, accompanied by dedicated electronics and software for stand alone usage. We conducted a thorough characterization, validating experimental observations through Monte Carlo simulations using the GEANT4 simulation package. In scattering environment, with a probe-source distance of 30 mm, the experimental results show that the detector sensitivity is 120 ± 5 cps/MBq, and the spatial and angular resolutions, in terms of full width at half maximum (FWHM), are 44.8 ± 1.3 mm and 87.3 ± 1 . 5 ∘ , respectively. The shielding effectiveness of the probe was determined to be greater than 95 % . The prototype with active shielding was found to have comparable performance to conventional gamma probes.

Effectiveness of multimedia-assisted training on inhaler usage technique, which is the optimum technique?

OBJECTIVE: In this study, we aimed to investigate the most appropriate education method for patients to use their inhaler devices with the proper technique. PATIENTS AND METHODS: The study had a cross-sectional, multicenter design. 525 consecutive patients who had never used an inhaler therapy before were included in the study. Seven different types of inhalers were evaluated. 75 patients were included for each device type. For each device type, 25 patients were trained by their own physicians who personally demonstrated the use of the device [verbal education with physical demonstration (VEWPD)], 25 were given multimedia-assisted training (MAT), and 25 received both types of training together (first VEWPD followed by MAT). After the patients were trained, inhaler medications were used under the supervision of a physician. Correct use of the inhaler devices and perceptions of convenience were scored. RESULTS: For Ellipta inhaler device and Levered Diskus inhaler device, the proportion of patients using their devices properly was significantly higher in patients who were instructed with both of the methods together compared to other education groups (p = 0.011, p = 0.015). The effects of different types of training on learning in Sanohaler, Diskus inhaler, and Pressurized metered dose inhaler devices were the same. CONCLUSIONS: We could not come to a conclusion that multimedia training was more beneficial than other training. As an unexpected result, in almost all of the devices, patients who received multimedia training in combination with verbal training did not develop better learning despite being shown the use of the device twice (except Ellipta inhaler, and Levered Diskus inhaler device).

Fournier's Gangrene: Our Five-Year Series and the Role of Vacuum-Assisted Closure in the Treatment.

BACKGROUND: Fournier's Gangrene (FG) is the necrotizing fasciitis of the perineal region. AIMS: To compare the effectiveness of debridement alone and debridement with vacuum-assisted closure in the treatment of Fournier's gangrene. METHODS: Twenty-two patients operated for FG were analyzed retrospectively. Debridement-only and debridement + VAC treatment groups were compared in terms of age, gender, predisposing factors, comorbid diseases, intensive care unit and hospital stay durations, laboratory results, septic shock, treatment methods, Fournier' gangrene severity index (FGSI) and mortality. RESULTS: The M/F ratio was 13/9. There were 10 and 12 patients in debridement-only and debridement + VAC groups, respectively. Ten patients (45.5%) were admitted to intensive care unit, 8 (36.4%) needed colostomy and 7 (31.9%) developed septic shock, respectively. The mortality rate was 27.3%. There was no significant difference in terms of age, gender, laboratory parameters, number of debridement, length of stay in intensive care unit and hospital, shock duration, and mortality (P > 0.05). The FGSI scores also did not show any difference between the groups which showed that the severity of the disease in both groups are similar. CONCLUSION: The VAC treatment was found not to provide a statistically significant benefit on mortality. Early and adequate debridement and antibiotic are still the most important factors in the treatment of FG and to reduce mortality.

Efficacy and Safety of ATG-Fresenius as an Induction Agent in Living-Donor Kidney Transplantation.

BACKGROUND: Induction therapy is mostly recommended for deceased-donor transplantation, whereas it has some controversies in live-donor transplantation. In this study, we described the outcomes of live-donor renal transplant recipients who received ATG-Fresenius (ATG-F) induction. METHODS: Live-donor transplantations in patients over 18 years old with ATG-F induction between 2009 and 2015 were included. All patients received quadruple immunosuppression, one of which was ATG-F induction. Biopsies after the artery anastomosis (zero hour) and protocol biopsies at the 6th month and at the 1st first year were obtained. Acute graft dysfunction was defined as a 20% to 25% increase in creatinine level from baseline. All acute rejection episodes were biopsy-confirmed. All episodes were initially treated with intravenous methyl prednisolone (MP) or ATG-F if resistant to MP. Four hundred twenty-two patients with live-donor transplantation were evaluated. The mean age was 40 ± 13 (18-73) years. The mean panel-reactive antibody levels were 42% ± 30% and 45% ± 30% for class I and II, respectively. RESULTS: The mean mismatch number for living unrelated donors (n = 112) was 4.6 ± 1.0. Acute rejection rate was 29.1% (123 patients) within the first year. The mean cumulative ATG-F doses for per patient and per kilogram were 344 ± 217 mg and 5.1 ± 2.7 mg, respectively. Patient survival rates were 98.3% and 96.7% for 12 months and 60 months, respectively. Death-censored graft survival rates were 97.6% and 92.1% for 12 months and 60 months, respectively. CONCLUSIONS: ATG-F induction provided excellent graft and patient survival rates without any significantly increased side effects. Increasing sensitized patient numbers, more unrelated donors, increasing re-transplantation numbers, and more desensitization protocols make ATG-F more favorable in an induction regimen.

Long-Term Effect of Sublingual and Subcutaneous Immunotherapy in Dust Mite-Allergic Children With Asthma/Rhinitis: A 3-Year Prospective Randomized Controlled Trial.

BACKGROUND AND OBJECTIVE: Specific allergen immunotherapy is the only treatment modality that might change the natural course of allergic diseases in childhood. We sought to prospectively compare the long-term clinical and immunological effects of sublingual (SLIT) and subcutaneous (SCIT) immunotherapy compared with pharmacotherapy alone. METHODS: In this single-center, prospective randomized controlled trial, 48 children with mild persistent asthma with/without rhinitis, monosensitized to house dust mites (HDMs) were followed for 3 years. At baseline and years 1 and 3 of follow-up, patients were evaluated and compared for total rhinitis (TRSS) and asthma (TASS) symptom scores, total symptom scores (TSS), total medication scores (TMS), safety profiles, skin-nasal-bronchial reactivity, and immunological parameters. RESULTS: A significant reduction was observed in TASS for both HDM-SCIT and HDM-SLIT at year 3 of treatment compared with baseline and controls (P<.05 for both), with significant improvement in rhinitis symptoms for both groups compared with controls (P=.01 for both). TSS decreased significantly in both HDM-SCIT and HDM-SLIT at year 3 compared with baseline (P=.007 and P=.04, respectively) and controls (P<.01 for both). A significant reduction in TMS was observed in HDM-SCIT and HDM-SLIT compared with baseline and controls (P=.01 in all cases), with a reduction in skin reactivity to HDM (P<.05). Finally, a significant increase in allergen specific IgG4 was observed in the SCIT group at year 3 compared with baseline, the SLIT group, and controls (P<.001 in all cases). CONCLUSIONS: HDM-sensitized asthmatic children treated for at least 3 years with either SCIT or SLIT showed sustained clinical improvement.

Gated myocardial perfusion scintigraphy in children with sickle cell anemia: correlation with echocardiography.

OBJECTIVES: The heart is one of the organs affected by sickle cell anemia (SCA). This prospective study has aimed to evaluate myocardial perfusion and left ventricle (LV) function in children with SCA by gated myocardial perfusion scintigraphy (G-MPS) and to compare the results with echocardiographic parameters. METHODS: Forty-three patients with SCA were evaluated by G-MPS and echocardiography. Myocardial perfusion and motion with thickening function were analyzed both visually and quantitatively. End-diastolic (EDV), end-systolic volumes (ESV), ejection fraction (EF), lung-to-heart (L/H) ratio were also calculated. RESULTS: None of the patients showed stress perfusion impairment in G-MPS. LV dilatation in 15 patients was observed both by G-MPS and echocardiography. EF values were within normal limits. Correlation between EF values calculated by two methods was not statistically significant. However, LV dilatation detected by both methods and EDV-ESV values in G-MPS were correlated to end-diastolic and end-systolic diameters calculated in echocardiography (p<0.05). M-Mode echocardiography revealed higher myocardial performance index (LV-MPI) in patients with LV dilatation. There was also a significant relationship between LV dilatation and frequent blood transfusions (>5/years) and acute chest syndrome (p<0.05). CONCLUSION: Myocardial perfusion impairment in children with SCA is not frequently observed. Thus, performing the scintigraphy only in patients with cardiac symptoms should be considered. Since EF values of the children with SCA are not deteriorated in early stages, LV-MPI and LV dilatation should be considered as a significant parameter other than EF or perfusion data.

Left ventricular wall function abnormalities in patients with ankylosing spondylitis evaluated by gated myocardial perfusion scintigraphy.

BACKGROUND: Ankylosing spondilitis (AS) is a chronic inflammatory disease with prominent inflammation in joints and extraarticular organs. AS patients have approximately two times more risk of mortality than the normal population. One reason for this increase in mortality is increased cardiovascular risk. In this study, we have aimed to evaluate myocardial perfusion and left ventricular function using (99m)Tc-MIBI gated myocardial perfusion single photon emission computed tomography (SPECT). MATERIAL AND METHODS: The study group consisted of 28 AS patients (19 men, 9 women), and mean age 39.46±10.98 years. All patients underwent (99m)Tc-MIBI gated myocardial perfusion SPECT with the same day protocol. RESULTS: We detected various risk factors including smoking habits in 12, family history of cardiovascular disease in 12, hypertension in 3, hyperlipidemia in 9 patients. We performed a myocardial perfusion SPECT for each patient and found normal perfusion pattern in SPECT images. Out of 28 patients, eight patients had normal perfusion but wall motion abnormalities. CONCLUSION: We detected that myocardial perfusion is preserved in the patients with AS. However, left ventricular wall motion abnormalities are seen. We concluded that ankylosing spondylitis may be associated with microvascular dysfunction and gated myocardial perfusion scintigraphy could be valuable in AS patients for the evaluation of LV function even if the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) score are low and the disease duration shorter.

Asymmetrically increased uptake in upper extremities on (99m)Tc-MDP bone scintigraphy caused by intra-arterial injection: different uptake patterns in three cases.

Unexpected findings on bone scintigraphy such as asymmetrical uptake in extremities may cause confusion for the diagnosis. The authors describe three cases of accidental intraarterial injection of Tc-(99m) methylene diphosphonate ((99m)Tc-MDP) on the antecubital region and discuss the findings and differential diagnosis.

Unusual extraosseous tumoral accumulation of 99mTc-MDP in non-Hodgkin's lymphoma in two cases.

The authors describe a rare pattern of soft tissue uptake observed in a (99m)Tc-MDP bone scintigraphy of two patients with the diagnosis of non-Hodgkin's lymphoma. Both patients had abdominal masses and bone scintigraphy revealed unusual (99m)Tc-MDP uptake in the abdominal region. The possible mechanisms of soft tissue uptake of bone seeking agents are discussed.

[Illness in emigration--a study of Turkish patients in general practice from the psychosomatic viewpoint]. / Krankheit in der Emigration--Eine Studie an türkischen Patientinnen in der Allgemeinpraxis aus psychosomatischer Sicht.

The study investigates psychosomatic disturbances in Turkish women patients treated in general practices. Our research-tools were the Giessen-List of psychosomatic complaints and the doctors' charts. 25 patients were extensively interviewed. The whole sample was divided into one subgroup of more, one of less acculturated women. There were significant differences between the groups: in the non-acculturated group we found more psychic symptoms (depression, loss of interest, hypersensitivity). Acculturated women tend to see the physician more frequently and are more often certified ill for physical symptoms. Compared with a German sample the Turkish women showed a significant higher prevalence of somatic complaints.