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This paper proposes a novel method for implementing robust controllers for active magnetic bearing (AMB) systems in a computationally cost-effective manner without affecting robust performance. The method decomposes the single-rate LTI controller into two parts, one containing slow modes and the other fast modes, where the slow and fast modes refer to the low and high-frequency modes, respectively, relative to a threshold frequency. Slow modes of the controller do not need to be implemented at a fast rate to achieve an accurate response and, therefore, can be implemented at a slow rate. This transforms the single-rate LTI controller into a dual-rate periodically time-varying controller and can significantly reduce the computational cost of necessary algebra at each time step using the interlacing technique. The novel part of the method is the selection of the dual-rate configuration, i.e., selection of the threshold frequency for the decomposition and the implementation rate of the slow modes. The proposed method utilizes the largest singular values of the closed-loop system along with μ-analysis and lifting technique to analyze robust performance of different dual-rate implementations and determines the optimal dual-rate configuration that maintains robust performance while maximizing computational savings. The presented method is demonstrated experimentally on an AMB test stand. A dual-rate configuration is identified that reduces the computational cost of the necessary controller algebra by 35% while maintaining robust performance. Experimental comparison of the performance and computational cost of the single-rate and the dual-rate implementations of the controller are shown. The results demonstrate the feasibility and potential of the presented method.

Vasospastic angina due to coronary vasospasm can lead to cardiac arrest. A 60-year-old man, active smoker, presented to the emergency department after being found unresponsive. An initial electrocardiogram showed a wide QRS, lateral ST-elevations, and massive reciprocal ST-depressions, which

A common tool utilized for the stability analysis of parametrically excited linear systems, such as rotors with cracked shafts, is Floquet׳s method. The disadvantage is a long calculation time needed to evaluate the monodromy matrix and instability zones. An efficient alternative is the generalized Bolotin׳s method, where the instability zones are evaluated quickly, yet the matrices that must be calculated are of large dimensions. In the present paper, the stability analysis is conducted with both Floquet׳s method and the generalized Bolotin׳s method. However, the order of the model is reduced to two modes only and stability analyses are performed for the second-order systems obtained with various combinations of the reducing modes. Then, the results of such analyses are collected in an overall stability map. The stability map obtained in this way closely reconstructs the stability map calculated with the full-order model of the rotor, yet the calculation time needed to generate the collected map as well as the dimension of the problem are considerably reduced. The approach is demonstrated with a mathematical model of the machine with the breathing crack modeled using the rigid finite element method. The rotor is not rotating, yet the stiffness of the shaft is varied periodically to simulate the parametric excitation. An interesting indication of the developing shaft crack observed in the generated stability maps is the presence of anti-resonant zones, where the rotor vibration amplitudes quickly decay. It is anticipated that this phenomenon of increased damping at specific excitation frequencies may have potential application for shaft crack detection.

Objectives To examine differences in conclusions, statistical significances, and quality of systematic reviews on preventive effects of different targets of blood glucose lowering on macrovascular events in patients with type 2 diabetes. Study Design and Setting We searched MEDLINE, the Cochrane Database of Systematic Reviews, and Embase until October 15, 2011. Systematic reviews using meta-analyses to compare macrovascular events in patients with type 2 diabetes randomized to different therapeutic targets of blood glucose were eligible for inclusion in this study. Effect measures were extracted and quality was assessed by Overview Quality Assessment Questionnaire, Assessment of Multiple Systematic Reviews, and Preferred Reporting Items for Systematic Reviews and Meta-Analyses. An additional checklist was used to control for completeness and suitability of included trials, correctness of data extraction, and choice of outcome parameters. Results The 16 included systematic reviews were partially discrepant in statistical significances of reported outcome parameters. Twelve systematic reviews did not include available relevant trials and included eight systematic reviews that should not have been included according to the systematic review's aim and search strategies. Quality differed considerably among systematic reviews. Conclusion Physicians, researchers, and policy makers should bear in mind that common quality assessment instruments are necessary but not sufficient to guarantee reliable results and conclusions obtained from meta-analyses.

The article introduces a new mathematical model for the cracked rotating shaft. The model is based on the rigid finite element (RFE) method, which has previously been successfully applied for the dynamic analysis of many complicated, mechanical structures. In this article, the RFE method is extended and adopted for the modeling of rotating machines. An original concept of crack modeling utilizing the RFE method is developed. The crack is presented as a set of spring–damping elements of variable stiffness connecting two sections of the shaft. An alternative approach for approximating the breathing mechanism of the crack is introduced. The approach is simple and allows one to intuitively and systematically prepare and analyze the model of a cracked rotor. The proposed method is illustrated with numerical and experimental results. The experiments conducted for the uncracked free–free rotor as well as the numerical results obtained with other software confirm the accuracy of the RFE model. The numerical analysis conducted for a set of cracked rotors has shown that, depending on the eccentricity and its angular location, the breathing behavior of the crack may take different forms. In spite of this, the frequency spectra for different cracks are almost identical. Due to its simplicity and numerous advantages, the proposed approach may be useful for rotor crack detection, especially if methods utilizing the mathematical model of the rotor are applied.

Cracked rotors are not only important from a practical and economic viewpoint, they also exhibit interesting dynamics. This paper investigates the modelling and analysis of machines with breathing cracks, which open and close due to the self-weight of the rotor, producing a parametric excitation. After reviewing the modelling of cracked rotors, the paper analyses the use of auxiliary excitation of the shaft, often implemented using active magnetic bearings to detect cracks. Applying a sinusoidal excitation generates response frequencies that are combinations of the rotor spin speed and excitation frequency. Previously this system was analysed using multiple scales analysis; this paper suggests an alternative approach based on the harmonic balance method, and validates this approach using simulated and experimental results. Consideration is also given to some issues to enable this approach to become a robust condition monitoring technique for cracked shafts.

IFNα exerts potent inhibitory activities against malignant melanoma cells in vitro and in vivo, but the mechanisms by which it generates its antitumor effects remain unknown. We examined the effects of interferon α (IFNα) on the expression of human members of the Schlafen (SLFN) family of genes, a group of cell cycle regulators that mediate growth-inhibitory responses. Using quantitative RT-real time PCR, we found detectable basal expression of all the different human SLFN genes examined (SLFN5, SLFN11, SLFN12, SLFN13, and SLFN14), in malignant melanoma cells and primary normal human melanocytes, but SLFN5 basal expression was suppressed in all analyzed melanoma cell lines. Treatment of melanoma cells with IFNα resulted in induction of expression of SLFN5 in malignant cells, suggesting a potential involvement of this gene in the antitumor effects of IFNα. Importantly, stable knockdown of SLFN5 in malignant melanoma cells resulted in increased anchorage-independent growth, as evidenced by enhanced colony formation in soft agar assays. Moreover, SLFN5 knockdown also resulted in increased invasion in three-dimensional collagen, suggesting a dual role for SLFN5 in the regulation of invasion and anchorage-independent growth of melanoma cells. Altogether, our findings suggest an important role for the SLFN family of proteins in the generation of the anti-melanoma effects of IFNα and for the first time directly implicate a member of the human SLFN family in the regulation of cell invasion.

Esophagectomy is indicated occasionally for the treatment of patients with refractory gastroesophageal reflux disease (GERD) or recurrent hiatus hernia. The purpose of this study was to evaluate the impact of previous gastroesophageal operations on outcomes after esophagectomy for recurrent GERD or hiatus hernia.Using a prospectively accumulated database, a retrospective review was performed to identify patients undergoing esophagectomy for complicated GERD or hiatus hernia. Mortality, perioperative and functional outcomes, and need for reoperation were evaluated, assessing esophagectomy patients who had undergone prior operations for GERD or hiatus hernia.Of 258 patients with GERD or hiatus hernia undergoing esophagectomy, 104 had undergone a previous operation, with a median interval to esophagectomy of 28 months. Transhiatal resection was accomplished in fewer patients undergoing reoperation (87 of 104 versus 151 of 154; p0.005). A gastric conduit was used as an esophageal replacement in fewer patients with previous operation(s) (89 of 104 versus 150 of 154; p0.005). Esophagectomy patients with a history of prior gastroesophageal surgery, as compared with those without, sustained more blood loss and were more likely to require reoperation, and fewer reported good to excellent swallowing function (p0.05). There was no difference in the occurrence of anastomotic leak.Esophagectomy in patients who have undergone prior operations for either GERD or hiatus hernia can be accomplished without thoracotomy and with satisfactory intermediate-term quality of life. Such patients should be evaluated and prepared for the use of alternative conduits should the remobilized stomach prove to be an unsatisfactory esophageal substitute at the time of esophagectomy.

Section 35b of the German Code of Social Law Book V (SGB V) mentions "expert approved international standards of evidence-based medicine" (EbM). An idea which started as a reform movement in and for clinical medicine more than twenty years ago is here, from a socio-legal perspective, being utilised as a normative concept in terms of a standard-creating methodology, which is meant to form the basis for the "methods and criteria" of comparative benefit/risk assessment of medical drugs mentioned in the respective law. The present paper places the standards in a hierarchy between "description and analysis of benefits" at the bottom and, at the top, "fundamental concerns of EbM". Apart from a variety of standards, we propose seven basic principles and four fundamental concerns of EbM (pursuit of empirical truth, patient welfare, pragmatism, procedural justice). Each of the basic principles, standards, methods and criteria can be taken to substantiate the respective superordinate category (basic concerns etc.). The position and role of the standards will be explained using the example "search for and selection of literature".

Purpose : To evaluate the feasibility and toxicity of continuous 7-day-a-week pelvic irradiation with no breaks between external beam irradiation and intracavitary applications. Material and methods : Between November 1998 and December 1999, 30 patients with FIGO Stage IIB or IIIB cervical cancer were treated with continuous 7-day-a-week pelvic irradiation, to the total Manchester point B dose of 40.0–57.6 Gy. The first 13 patients (group A) were applied a daily tumor dose of 1.6 Gy and the remaining 17 patients (group B)-10.8 Gy. One or two immediate brachytherapy applications (point A dose 10–20 Gy, each) were performed in 28 cases. Results : Two patients did not complete the irradiation due to apparent early progression of disease during the irradiation. Of the remaining 28 evaluable patients 11 (39%) completed treatment within the prescribed overall treatment time and 17 had unplanned treatment breaks. For the latter group overall treatment time ranged from 103 to 122% (mean 114%) and from 103 to 197% (mean 138%) of the planned treatment time for group A and B, respectively. The majority of patients experienced acute toxicity. Severe toxicity (EORTC/RTOG grade 3 and 4), predominantly gastrointestinal, occurred in 5 of the 13 patients in group A, and in 7 of 17 patients in group B. Conclusion : The studied regimen was accompanied by considerable toxicity, hindering delivery of irradiation within planned treatment time.

A new approach for uncoupling the equations of motion typical for rotordynamical systems is presented. The method does not neglect the speed-dependent effects, such as gyroscopic effects, and can be particularly valuable in the controller design of actively controlled rotors. In the presence of hysteretic type of damping, the resulting uncoupled gyroscopic systems come with an equivalent viscous damping, equivalent in a sense of yielding the same natural frequency and decay rate. The approach is illustrated through three examples of technical interest: a Jeffcott rotor with hysteretic damping, a Stodola–Green rotor, and a rotor of a small gas turbine. The generated results demonstrate that the developed approach is correct and straightforward.

Based on the Louiville–Riemann fractional formulation of lumped hysteretic mechanical system simulations, asymptotic-type relationships are derived. These are employed to determine how such operators, which act as viscoelastic elements, partition system energy into conservative and nonconservative components. Special emphasis is given to: (a) determine how operator order serves to weigh such a splitting, (b) determine how partitioning affects system phasing and amplitude response, and (c) to establish how conservative and nonconservative effects modulate during a given system cycle. The generality of the undertaken approach is such that multi-element fractional Kelvin Voigt formulations subject to spectrally rich inputs can be handled, i.e., the multi-modal splitting of energies. As a result of the insights derived, improved frequency dependent simulations of system amplitude, phasing and energetics will be possible.

This paper explores the use of diophantinized fractional fits for the nonlinear constitutive representation of elastomeric media. These are caste in terms of either the principal stretches or the strain invariants. Both polynomial and rational forms are considered. To construct the requisite complete and physically admissible basis space, the diophantinized set of fractional powers is bound by the curvature properties of the experimental data set. This set is then employed in conjunction with a remezed least square scheme to obtain an optimal fit. To verify the scheme a sample application case is presented.

In this letter we show that for flexible structures with small non proportional damping, neglecting the off diagonal terms of the modal damping matrix in most practical cases imposes negligible errors in the system dynamics. The Shahruz criterion, which allows neglecting the off diagonal terms of the modal matrix, was relaxed

The overall quality of antihypertensive care in diabetic patients in Germany is poor. Only a minority of unselected hypertensive patients reach permanent normotensive blood pressure control. Previously, we have shown in a prospective randomized 3-year follow-up study in essential hypertension that implementation of a hypertension teaching and treatment program into routine care results in a significant improvement of blood pressure control. Subsequently, we have performed a prospective, controlled 5-year follow-up trial in hypertensive type I diabetic patients with nephropathy. One-half of a sequential sample of about 100 hypertensive patients with overt nephropathy participated in the program based on blood pressure self-monitoring with the goal of normalization of blood pressure values below 140/90 mm Hg (intensified care, IC). The remaining patients followed routine antihypertensive therapy and formed the control group (routine care, RC). During 5 years of follow-up in IC group patients, blood pressure control was significantly improved. The occurrence of primary study end points (need for dialysis and death) was significantly lower in the IC group patients. In conclusion, in patients with diabetic nephropathy, participation in a hypertension teaching treatment program results in a long-term improvement of blood pressure control and a decrease in mortality and morbidity.

Wstep Podwyzszenie dawki w obszarze lozy po usunietym guzie u chorych leczonych metodą z zachowaniem narządu (ang. breast-conserving therapy, BCT) zmniejsza czestośc nawrotow miejscowych. W praktyce wyznaczenie obszaru lozy napotyka trudności. Zastosowanie BT ze środoperacyjnym umieszczeniem prowadnic w obszarze lozy guza pozwala zminimalizowac ryzyko popelnienia bledu lokalizacyjnego. Material i metody U 30 chorych na raka piersi (T1-3N0-2M0, w wieku 38–64 lat) leczonych BCT jako boost zastosowano BT ze środoperacyjnym wprowadzeniem miekkich prowadnic. Zabieg operacyjny stanowil pierwotne leczenie (11 ch) lub poszerzenie marginesu po uprzedniej biopsji ekscyzyjnej (19 ch). W obu przypadkach rownocześnie usuwano wezly chlonne. Podczas zabiegu dokonywano rekonstrukcji gruczolu. BT w dawce 15 Gy (1 Gy/puls/godz.) rozpoczynano nastepnego dnia, a napromienianie piersi wiązką zewnetrzną (RT) – po 1–4 tygodniach. Stosowano aparat microSelectron PDR zawierający źrodlo 192lr. Rozklad dawki w obszarze implantu wyznaczano komputerowo wg systemu paryskiego, stosując optymalizacje geo-metryczną objetościową. Wyniki Wprowadzenie prowadnic do BT przedluzalo zabieg o ok. 15 minut. Za wyjątkiem 2 chorych, zastosowano implant 2-plaszczyznowy z uzyciem 5–9 (średnio 8) prowadnic. Średnia objetośc leczona (V100) wynosila 37,6 cm3. Zabiegowi nie towarzyszylo zwiekszone krwawienie. BT POR byla bardzo dobrze tolerowana. Martwica tluszczowa, z koniecznością powtornego wyciecia tkanek, wystąpila u 1 chorej, co spowodowalo opoźnienie RT wiązką zewnetrzną o miesiąc. Wnioski Okolooperacyjna BT PDR jest prostą, dobrze tolerowaną przez chorych metodą podania dodatkowej dawki w leczeniu BCT. Środoperacyjne umieszczenie prowadnic umozliwia najbardziej dokladne wyznaczenie obszaru wysokiej dawki. Krotki okres obserwacji wiekszości chorych nie pozwala na ocene wynikow leczenia i poźnych nastepstw.

Material and method Between May 1999 and January 2001, 41 consecutive cervical cancer patients (pts), median age 46 yrs (range 29–68), were treated with concurrent cisplatin and pelvic irradiation with curative intent (29 pts FIGO stage IB “bulky”, IIB–IVA) or postoperatively (11 pts who had positive pelvic lymph nodes and/or involvement of the surgical margin and/or large and deeply invasive lesion). Adequate bone marrow function and normal serum creatinine were required. Cisplatin given as a 60-minute infusion, was administered weekly at the dose of 40 mg/sqm (max. 70 mg) for six cycles. Antiemetic therapy was routinely given. Three patients received irradiation on out-patient basis. Results A total of 145 cycles were administered. The median number of cisplatin cycles was 4 (range: 1–6). Overall, 65% of pts received at least four cycles of cisplatin. The reasons for chemotherapy discontinuation included low level of creatinine clearence (2 pts), worsening of performance status (3 pts), and myoclonia after cisplatin injection (1 pt). Moderate emesis occurred in one patient, grade 2 leukopenia in two other cases. There were no severe acute effects precluding the delivery of planned radiotherapy. At present six patients are still on therapy. Conclusion Pelvic radiotherapy combined with weekly cisplatin is feasible in a routine practice. This modality is also suitable for patients treated on out-patient basis.

www.thelancet.com Vol 374 November 21, 2009 1743 LAA trauma may relate to the fi xation barbs. Too enthusiastic a tug on the device during stability testing may result in a pericardial eff usion requiring intervention. The paper reports that fi ve of 408 patients who had a device implanted had periprocedural strokes, and this was attributed by Holmes and colleagues to be “mainly air embolism”. Air embolisation can generally be overcome with studious attention to de-airing of catheters and devices. Now that percutaneous coronary intervention has already passed its zenith, it may be tempting for coronary interventionalists to turn their hands to this procedure. However, the complication rates of the PROTECT AF study herald a warning against this. We recommend that the procedure only be adopted by operators experienced at structural intervention in the left atrium (in particular atrial septal closure).

Wstep i cel pracy Podstawową metodą leczenia chorych na raka trzonu macicy jest radykalny zabieg operacyjny. U wielu chorych w tej grupie wystepują jednak rownocześnie schorzenia internistyczne - choroby ukladu sercowo-naczyniowego, ukladu oddechowego, choroby metaboliczne lub zwyrodnienie ukladu kostno-stawowego, ktore w 3.5–9% przypadkow nie pozwalają na wykonanie zabiegu operacyjnego. U tych chorych jedynym mozliwym leczeniem jest radioterapia. W pracy przedstawiono wlasne doświadczenia dotyczące brachyterapii PDR Ir 192 z zastosowaniem domacicznych aplikatorow Normana Simona u chorych na raka trzonu macicy leczonych w Klinice Onkologii i Radioterapii AM w Gdansku w latach 2000–2004. Material i metody Ogolem BT PDR zastosowano u 9 chorych w wieku od 72 do 92 lat, ktore ze wzgledow internistycznych nie kwalifikowaly sie do leczenia operacyjnego, z wyjątkiem jednej chorej, u ktorej zastosowano BT przedoperacyjną. U 5 chorych zastosowano jedyne BT w dawce calkowitej 50–65 Gy (4–6 aplikacje), a u 3 dawke 20 Gy w 2 aplikacjach oraz dodatkowo teleterapie w dawce −50 Gy (dawka frakcyjna 2 Gy). Stosowano 2.5 Gy/ puls powtarzany co godzine. Wyniki Tolerancja leczenia byla bardzo dobra. W okresie obserwacji trwającej od 3 do 45 miesiecy (mediana 28 miesiecy), u zadnej chorej nie doszlo do poźnych odczynow popromiennych ze strony pecherza moczowego lub odbytnicy. 5 chorych, w tym chora operowana, po leczeniu BT PDR, czuje sie dobrze i nie stwierdza sie u nich nawrotu choroby. U 2 chorych doszlo do wznowy miejscowej, odpowiednio po 2.5 i po prawie 4 latach po zakonczeniu leczenia. Jedna chora zmarla z powodu. wspolistniejącego raka piersi. Jedna chora zmarla wkrotce po ukonczeniu leczenia. Wniosek Wstepne wyniki wskazują na dobrą tolerancje wewnątrzmacicznej brachyterapii PDR z zastosowaniem aplikatorow Normana Simona u chorych na raka trzonu macicy nie kwalifikujących sie do leczenia operacyjnego. U cześci chorych metoda ta pozwala uzyskac dlugotrwale przezycie bez cech nawrotu.

Wstep Brachyterapia pulsacyjna (BT PDR) lączy zalety radiobiologiczne metody LDR oraz techniczne metody HDR. Z tych powodow jest szczegolnie przydatna w przypadkach powtornej radioterapii, obarczonej wysokim ryzykiem powiklan. Obok popularnych technik środjamowych i środtkankowych BT stosuje sie takze BT kontaktową, ktora wymaga sporządzenia indywidualnych utrzymywaczy prowadnic. Material i metody Przedstawiono 3 przypadki chorych poddanych kontaktowej BT PDR z uzyciem indywidualnie wykonanych aplikatorow. W2 przypadkach bylo to powtorne napromienianie po radykalnej radioterapii (RT) raka okolicy oczodolu oraz raka zatoki szczekowej, a w 1 stanowila element pierwotnej radykalnej RT. W powtornym napromienianiu stosowano dawke 50 Gy, a w skojarzonej RT 15 Gy (w obu zastosowaniach 0.6 Gy/puls/1godzine). Rozklad dawki obliczano komputerowo przy uzyciu systemu PLATO na podstawie zdjec TK lub rtg. Akrylowe aplikatory wykonywano na podstawie wycisku pobranego przy uzyciu masyelastomerowej. Wyniki Uzyskano dokladne dopasowanie aplikatorow do jam ciala i/lub lozy po usunietych guzach, co pozwolilo uzyskac zadowalający rozklad dawki i zapobiegalo przemieszczeniom aplikatorow w trakcie leczenia. Chorzy tolerowali leczenie bardzo dobrze. Ostry odczyn popromienny o niewielkim nasileniu obserwowano po uplywie 2–3 tygodni od zakonczenia leczenia. Wnioski Wykonanie indywidualnych aplikatorow umozliwia przeprowadzenie BT w trudno dostepnych obszarach anatomicznych. Dzieki precyzyjnie odwzorowującym podloze nowoczesnym elastomerowym masom stomatologicznym udaje sie wykonac dokladnie dopasowane aplikatory do BT kontaktowej. Uzycie techniki PDR pozwala na precyzyjne napromienienie zaplanowanej objetości przy rownoczesnej ochronie zdrowych tkanek.

Plasma concentrations of atrial natriuretic factor (ANF) were measured by radioreceptor assay in 148 insulin-dependent Type I diabetic patients with different stages of diabetic nephropathy. In patients with overt or incipient diabetic nephropathy as well as in patients with glomerular hyperfiltration only, ANF concentrations were elevated when compared with non-nephropathic diabetic and normal subjects. No correlations between ANF and blood pressure, age, diabetes duration, or parameters of metabolic control were found. These findings may indicate a pathophysiologic role of ANF in the development and progression of diabetic nephropathy.