X ray Fourier transform holography with beam shaping optical elements

Holography is a powerful method for achieving 3D images of objects. Extending this method to short wavelengths potentially offers significantly higher resolution than visible light holography. However, current X ray holography setups employ nanoscale pinholes to form the reference wave. This approach is relatively inefficient and limited to very small sample size. Here, we propose a new setup for X ray holography based on a binary diffractive optical element DOE , which forms at the same time the object illumination and the reference wave. This optic is located separately from the sample plane, which permits investigation of larger sample areas. Using an extended test sample, we demonstrate a resolution of 90 nm half pitch at an undulator beamline at BESSY II. The new holography setup can be directly transferred to free electron laser sources enabling time resolved nanoscale imaging for ultra fast processe

Combining gemcitabine, oxaliplatin and capecitabine (GEMOXEL) for patients with advanced pancreatic carcinoma (APC): a phase I/II trial

Background: Gemcitabine remains the mainstay of palliative treatment of advanced pancreatic carcinoma (APC). Adding capecitabine or a platinum derivative each significantly prolonged survival in recent meta-analyses. The purpose of this study was to determine dose, safety and preliminary efficacy of a first-line regimen combining all three classes of active cytotoxic drugs in APC. Patients and methods: Chemotherapy-naive patients with locally advanced or metastatic, histologically proven adenocarcinoma of the pancreas were treated with a 21-day regimen of gemcitabine [1000 mg/m2 day (d) 1, d8], escalating doses of oxaliplatin (80-130 mg/m2 d1) and capecitabine (650-800 mg/m2 b.i.d. d1-d14). The recommended dose (RD), determined in the phase I part of the study by interpatient dose escalation in cohorts of three to six patients, was further studied in a two-stage phase II part with the primary end point of response rate by RECIST criteria. Results: Forty-five patients were treated with a total of 203 treatment cycles. Thrombocytopenia and diarrhea were the toxic effects limiting the dose to an RD of gemcitabine 1000 mg/m2 d1, d8; oxaliplatin 130 mg/m2 d1 and capecitabine 650 mg/m2 b.i.d. d1-14. Central independent radiological review showed partial remissions in 41% [95% confidence interval (CI) 26% to 56%] of patients and disease stabilization in 37% (95% CI 22% to 52%) of patients. Conclusion: This triple combination is feasible and, by far, met the predefined efficacy criteria warranting further investigation

Vergleich von audiologischen Ergebnissen und klinischen Einflussfaktoren bei Patienten mit Mittelohrteilprothese: TTP® Tübinger Titanprothese vs. CliP Partial FlexiBAL®

Einleitung: Einige derzeit häufig verwendete Mittelohrprothesen (z.B. TTP® Tübinger Titanprothese) zum partiellen Ersatz der Ossikelkette können die gelenkige Verbindung zwischen Hammer, Amboss und Steigbügel nicht nachbilden. Um eine bessere Angulierung der Pauckenabdeckung gegenüber der Steigbügelüberhöhung zur erreichen, wird seit einigen Jahren eine Prothese kommerziell angeboten (CliP Partial FlexiBAL®), die über ein integriertes Mikrokugelgelenk verfügt. Material und Methoden: Insgesamt wurden 190 Patienten ausgewertet, die 2010-2013 im Universitätsklinikum Halle (Saale) eine Mittelohroperation mit Einsatz einer TTP® (n=148) oder einer FlexiBAL® (n=42) erhielten. Reintonhörschwellen (0.5, 1, 2, 3 kHz ) und das "Air-Bone Gap" (ABG) wurden 2 Monate, 6-12, und >1 Jahr nach OP ausgewertet und der Einfluss von Faktoren wie ('Diagnose', 'Prothesenlänge', 'Anzahl der Revisionen', 'Gehörknöchelchenstatus', 'Ausmaß der Operation') analysiert. Ergebnisse: Das mittlere ABG verringerte sich über alle Messzeitpunkte (2 Monate: 20.2 dB, 6-12 Monate: 20.4 dB, >1 Jahr: 16.8 dB) im Vergleich zu den präoperativen Ausgangswerten (25.2 dB). Die Varianzanalyse zeigte 6-12 Monate nach OP einen signifikanten Unterschied zwischen den Prothesenarten (p=0.03) mit kleineren ABG (14.8 dB) bei der FlexiBAL® im Vergleich zur TTP® (22.6 dB). Stratifiziert nach Diagnosen zeigt sich dieser Effekt nur bei der Diagnose Cholesteatom.Schlussfolgerung: Die FlexiBAL® zeigte in der untersuchten Patienten-Population ein besseres mittel- bis langfristiges audiologisches Ergebnis im Vergleich zur TTP®, insbesondere bei Operationen aufgrund eines Cholesteatoms. Eine Ursache ist möglicherweise die subjektive Prothesenwahl durch den Operateur, abhängig vom intraoperativen Befund und der klinischen Parameter.Der Erstautor gibt keinen Interessenkonflikt an

Influence of random zone positioning errors on the resolving power of Fresnel zone plates

Fresnel zone plates produced by electron beam lithography and planar etching techniques provide a resolving power of about 10 nm. An alternative zone plate fabrication approach is based on alternately coating a micro wire with two different materials. With this process, very thin zone layers with very high aspect ratios can be deposited. However, depending on the fabrication method, random zone positioning errors may introduce strong aberrations. We simulate the effect of positioning errors using different random fluctuations and study their influence on zone plate resolution. We find that random errors significantly decrease the contrast transfer of X ray microscopes. Additionally, we derive an upper bound for the mean acceptable variance of the deposition rat

Complement pore genesis observed in erythrocyte membranes by fluorescence microscopic single-channel recording.

The formation and opening of single complement pores could be directly observed in erythrocyte ghosts by confocal laser-scanning microscopy employing the recently introduced method of fluorescence microscopic single-channel recording. Resealed sheep erythrocyte ghosts were incubated with human complement. By limiting the concentration of C8, the eighth component of complement, the fraction of cells rendered permeable for the small polar fluorescent probe Lucifer Yellow was varied between 0.50 and 0.90. Under each condition the flux rate, k, of Lucifer Yellow was determined for a substantial number of ghosts. By analysing the sample population distribution of k the flux rate k1 of ghosts with a single pore was found to be (4.8 +/- 1.1) x 10(-3) s-1 consistent with a pore radius of about 3.5 nm (35 A). The genesis of single complement pores was studied by continuous influx measurements while triggering pore formation by a temperature shift. Pore genesis was found to be a very slow process, proceeding on a time scale of several minutes. During pore genesis the influx curves had a sigmoid shape, which excluded the possibility that the pore was preformed on the membrane surface and subsequently inserted. However, the influx curves could be well simulated by a model which assumed that pores grow stepwise by sequential incorporation of C9 monomers. The model predicts conditions under which the incorporation of single monomers can be directly revealed

Strategien zur Angstreduktion in der Kleintierpraxis, Teil 2 Massnahmen zur Therapie, Prävention und Einsatz anxiolytischer Medikamente

Dieser Artikel beschreibt Maßnahmen, um Tierarztangst bei Hunden und Katzen zu behandeln oder gar nicht erst entstehen zu lassen. Dazu zählen die Anwendung einer Desensibilisierung und Gegenkonditionierung, das Schaffen positiver Assoziationen, beispielsweise im Rahmen von „Happy Visits“, sowie „Medical Training“, bei welchem die Tiere lernen, aktiv ihre Zustimmung zu Prozeduren zu geben, indem sie ein vorher trainiertes Verhalten ausführen. Anxiolytische Medikamente, welche durch die Besitzer vor dem Tierarztbesuch verabreicht werden, können weitere Negativerfahrungen verhindern und neue positive Verknüpfungen erleichtern. Im besten Fall kann Tierarztangst bei Hunden und Katzen durch Anwendung von stressreduzierenden Methoden und dem Ermöglichen positiver Erfahrungen verhindert werden. Besonders nachhaltige Auswirkungen kann dabei der erste Eindruck eines Hunde- oder Katzenwelpen beim Erstbesuch haben. Auch vorbereitendes Training (Gewöhnung an Berührungen, Transportbox- und Maulkorbtraining) leistet einen wichtigen Beitrag zum angstfreien Tierarztbesuch

Antenatal Diagnosis of Dizygotic, Monochorionic Twins Following IVF/ICSI

Monochorionic twins are usually monozygotic and thus usually have the same sex. A case of monochorionic diamniotic twins following IVF/ICSI and laser treatment of the zona pellucida (“assisted hatching”) is presented in which partial embryo amalgamation appears to have occurred. Discordant sex between the twins was suspected on detailed antenatal ultrasound at 13 + 3 weeks gestation and was confirmed on subsequent examinations. The sexual phenotype at birth was female for one twin and male for the other. Placental histology confirmed the monochorionic, diamniotic situation. Cytogenetic analysis of both twins was carried out postpartum on various tissues. On karyotyping of blood lymphocytes the male and female twins each had one mosaic of male and female cells. Oral mucosal cells showed normal male and female karyotypes respectively. Analysis of urothelium showed a normal result for the male infant, and a weak gonosomal mosaic with an XX and XY constellation for the female infant. At least for blood lymphocytes, a diagnosis of chimerism was proven