Diagnostische aspekten van in-vitro-fertilisatie (IVF) en transport van onbevruchte eicellen voor IVF

De onderzoekperiode liep van 1 januari 1982 tot en met februari 1985. Alle betrokken patienten waren wegens infertiliteit tevoren ingeschreven bij een gynaecologische polikliniek. Patiënten van de polikliniek van het Academisch Ziekenhuis Dijkzigt konden deelnemen vanaf l-1-'82, van het Zuiderziekenhuis te Rotterdam vanaf 1-10-'83. In principe konden alle patiënten toegelaten worden ongeacht de tot dan toe bekende oorza(a)k(en) van hun infertiliteit, met uitzondering van azoöspermie. Patiënten, die echter tevoren reeds waren behandeld via donorinseminatie (KID, 4 patiënten), konden wel worden toegelaten indien uitblijven van succes van donorinseminatie de indicatie voor nader infertiliteitsonderzoek was. 2.2 Procedure bij deelname aan de studiegroep. Op het moment dat door de behandelend arts van het echtpaar een laparoscopisch onderzoek van de genitalia interna van de vrouw geindiceerd werd geacht op basis van het voorafgaande infertiliteitsonderzoek werden de doelstellingen van het onderzoek aan hen uitgelegd. In een persoonlijk gesprek werden zowel de éénmaligheid van de poging tot in-vitro-bevruchting als de nog experimentele fase van het IVF onderzoek nader toegelicht. Beslissing omtrent dee~name werd meestal nog niet genomen tijdens dit gesprek. In verband met het testen van de doorgankelijkheid van de eileiders bij de laparoscopie voor infertiliteit werd dit onderzoek gepland in de eerste helft van de cyclus, dat wil zeggen vóór de eisprong had plaatsgevonden. Om dit mogelijk te maken werd het moment van laparoscopie pas vastgesteld nadat patiënte telefonisch had doorgegeven wanneer weer een menstruatie was opgetreden. Tijdens dit telefoongesprek werd een eventuele deelname aan de studie pas definitief. Hierdoor was er steeds minimaal een week bedenktijd na het eerste gesprek. In het eerste jaar van het onderzoek namen naar schatting 80% van de patiënten aan wie de doelstellingen waren uitgelegd deel. Geleidelijk werd dit vrijwel 100%

Symbol time offset estimation in coherent OFDM systems

This paper presents a symbol time offset estimator for coherent OFDM systems. This estimator exploits both the redundancy in the cyclic prefix and the pilot symbols used for channel estimation. The estimator is robust against frequency offsets and is suitable for use in dispersive channels. We base the estimator on the ML estimator for the AWGN channel. Simulations of an example system indicate a system performance as close as 0.3 dB to a perfectly synchronized system. Compared to an estimator not using pilots, our estimator's performance could allow a shorter cyclic prefix and thus a more spectrally efficient syste

Coupling global models for hydrology and nutrient loading to simulate nitrogen and phosphorus retention in surface water - Description of IMAGE-GNM and analysis of performance

The Integrated Model to Assess the Global Environment–Global Nutrient Model (IMAGE–GNM) is a global distributed, spatially explicit model using hydrology as the basis for describing nitrogen (N) and phosphorus (P) delivery to surface water, transport and in-stream retention in rivers, lakes, wetlands and reservoirs. It is part of the integrated assessment model IMAGE, which studies the interaction between society and the environment over prolonged time periods. In the IMAGE–GNM model, grid cells receive water with dissolved and suspended N and P from upstream grid cells; inside grid cells, N and P are delivered to water bodies via diffuse sources (surface runoff, shallow and deep groundwater, riparian zones; litterfall in floodplains; atmospheric deposition) and point sources (wastewater); N and P retention in a water body is calculated on the basis of the residence time of the water and nutrient uptake velocity; subsequently, water and nutrients are transported to downstream grid cells. Differences between model results and observed concentrations for a range of global rivers are acceptable given the global scale of the uncalibrated model. Sensitivity analysis with data for the year 2000 showed that runoff is a major factor for N and P delivery, retention and river export. For both N and P, uptake velocity and all factors used to compute the subgrid in-stream retention are important for total in-stream retention and river export. Soil N budgets, wastewater and all factors determining litterfall in floodplains are important for N delivery to surface water. For P the factors that determine the P content of the soil (soil P content and bulk density) are important factors for delivery and river export.FWN – Publicaties zonder aanstelling Universiteit Leide

A modified low-protein infant formula supports adequate growth in healthy, term infants:a randomized, double-blind, equivalence trial

Background: A high protein intake in early life is associated with a risk of obesity later in life. The essential amino acid requirements of formula-fed infants have been reassessed recently, enabling a reduction in total protein content and thus in protein intake. Objectives: We aimed to assess the safety of an infant formula with a modified amino acid profile and a modified low-protein (mLP) content in healthy term-born infants. Outcomes were compared with a specifically designed control (CTRL) infant formula. Methods: In this double-blind, randomized controlled equivalence trial, infants received either mLP (1.7 g protein/100 kcal; n = 90) or CTRL formula (2.1 g protein/100 kcal; n = 88) from enrollment (age ≤ 45 d) to 6 mo of age. A breastfed group served as a reference (n = 67). Anthropometry and body composition were determined at baseline, 17 wk (including safety blood parameters), and 6 mo of age. The primary outcome was daily weight gain from enrollment up until the age of 17 wk (at an equivalence margin of ±3.0 g/d). Results: Weight gain from baseline (mean ± SD age: 31 ± 9 d) up to the age of 17 wk was equivalent between the mLP and CTRL formula groups (27.9 and 28.8 g/d, respectively; difference:-0.86 g/d; 90% CI:-2.36, 0.63 g/d). No differences in other growth parameters, body composition, or in adverse events were observed. Urea was significantly lower in the mLP formula group than in the CTRL formula group (-0.74 mmol/L; 95% CI:-0.97,-0.51 mmol/L; P < 0.001). Growth rates, fat mass, fat-free mass, and several essential amino acids were significantly higher in both formula groups than in the breastfed reference group. Conclusions: Feeding an infant formula with a modified amino acid profile and a lower protein content from an average age of 1 mo until the age of 6 mo is safe and supports an adequate growth, similar to that of infants consuming CTRL formula. This trial was registered at www.trialregister.nl as Trial NL4677

Biochemical and Structural Characterization of a Uronic Acid Oxidase from Citrus sinensis

Aldaric acids are attractive diacids that can be prepared by selective oxidation of carbohydrates. For this, effective biocatalysts are in demand. This work reports on the discovery, biochemical and structural characterization of a VAO-type flavin-containing carbohydrate oxidase from Citrus sinensis: URAOCs3. URAOCs3 could be overexpressed using prokaryotic and eukaryotic expression systems. Extensive biochemical characterization revealed that the enzyme displays a high thermostability and an exquisite selectivity for uronic acids, galacturonic acid and glucuronic acid. The enzyme was further investigated by determining the crystal structure. The selective oxidation of D-galacturonic acid in a complex mixture was demonstrated, showing how URAOCs3 was found to be highly effective in selectively producing galactaric acid while leaving other carbohydrates untouched. In addition to the specific discovery of URAOCs3, these findings suggest that plant proteomes can be an interesting source for new biocatalysts.</p

Learning from failure

We study decentralized learning in organizations. Decentralization is captured through a symmetry constraint on agents’ strategies. Among such attainable strategies, we solve for optimal and equilibrium strategies. We model the organization as a repeated game with imperfectly observable actions. A fixed but unknown subset of action profiles are successes and all other action profiles are failures. The game is played until either there is a success or the time horizon is reached. For any time horizon, including infinity, we demonstrate existence of optimal attainable strategies and show that they are Nash equilibria. For some time horizons, we can solve explicitly for the optimal attainable strategies and show uniqueness. The solution connects the learning behavior of agents to the fundamentals that characterize the organization: Agents in the organization respond more slowly to failure as the future becomes more important, the size of the organization increases and the probability of success decreases.Game theory

Waardplantgeschiktheid van roos voor het wortelknobbelaaltje Meloidogyne hapla : zeven M. hapla-isolaten, zes cultivars en een onderstam

Het noordelijk wortelknobbelaaltje, Meloidogyne hapla, wordt de laatste jaren steeds vaker aangetroffen in substraatteelten van roos. Onderzoek naar de schadelijkheid en populatieontwikkeling van dit wortelaaltje bij roos op substraat vereist de aanwezigheid van een vatbare cultivar of onderstam en een M. hapla-isolaat dat tot aantasting in staat is. Omdat uit het eerste onderzoek bleek dat niet elke roos en isolaat een geschikte combinatie is, is een potproef uitgevoerd om geschikte roos/isolaat-combinaties te vinden. In de proef zijn zes rozencultivars, Black Beauty, Indian Femma!, Queensday, Red Berlin, Sunbeam en Vendela en de onderstam Natal Briar opgenomen in combinatie met zeven verschillende M. hapla-isolaten: Has, Haw, Hbz, Hby, Hh, Hj en RZ. Alle isolaten zijn getest in een zilverzand/perliet grof-substraat (2 : 1). Alleen het isolaat RZ is ook in kokos en perliet fijn beproefd. De planten zijn geïnoculeerd met 10.000 J2 van M. hapla per plant en negen weken later beoordeeld op aantallen eimassa’s per plant. Het tomatenras Moneymaker diende als zeer vatbare controle om de vitaliteit van de isolaten te controleren. In tegenstelling tot het tomatenras Moneymaker, waarop gemiddeld over alle M. hapla-isolaten 638 eimassa’s per plant aanwezig waren, waren de rozen met gemiddeld bijna 8 eimassa’s per plant beduidend minder vatbaar voor de geteste M. hapla-isolaten. Van de rozen zijn de onderstam Natal Briar en de cultivar Vendela het meest vatbaar, wat met name geldt voor de isolaten Hbz en Hh. Deze roos/isolaat-combinaties leverden 43 tot 58 eimassa’s per plant op. In combinatie met de andere cultivars varieerde het aantal eimassa’s voor Hbz en Hh van 0,2 tot 23,8 per plant. De isolaten Has, Haw, Hby, Hj en RZ, leverden bij alle onderzochte rozen geen of slechts weinig eimassa’s op, variërend van 0 tot 15,5 eimassa’s per plant. Dit onderzoek heeft vier roos/isolaat-combinaties opgeleverd waarmee de schade- en bestrijdingsproeven kunnen worden uitgevoerd, namelijk Natal Briar en Vendela in combinatie met de isolaten Hbz en Hh

Scattering of Stark-decelerated OH radicals with rare-gas atoms

We present a combined experimental and theoretical study on the rotationally inelastic scattering of OH (X\,^2\Pi_{3/2}, J=3/2, f) radicals with the collision partners He, Ne, Ar, Kr, Xe, and D$_2$ as a function of the collision energy between $\sim 70$ cm$^{-1}$ and 400~cm$^{-1}$. The OH radicals are state selected and velocity tuned prior to the collision using a Stark decelerator, and field-free parity-resolved state-to-state inelastic relative scattering cross sections are measured in a crossed molecular beam configuration. For all OH-rare gas atom systems excellent agreement is obtained with the cross sections predicted by close-coupling scattering calculations based on accurate \emph{ab initio} potential energy surfaces. This series of experiments complements recent studies on the scattering of OH radicals with Xe [Gilijamse \emph{et al.}, Science {\bf 313}, 1617 (2006)], Ar [Scharfenberg \emph{et al.}, Phys. Chem. Chem. Phys. {\bf 12}, 10660 (2010)], He, and D$_2$ [Kirste \emph{et al.}, Phys. Rev. A {\bf 82}, 042717 (2010)]. A comparison of the relative scattering cross sections for this set of collision partners reveals interesting trends in the scattering behavior.Comment: 10 pages, 5 figure

Effect of enzyme therapy and prognostic factors in 69 adults with Pompe disease: An open-label single-center study

Abstract. Background: Enzyme replacement therapy (ERT) in adults with Pompe disease, a progressive neuromuscular disorder, is of promising but variable efficacy. We investigated whether it alters the course of disease, and also identified potential prognostic factors. Methods. Patients in this open-label single-center study were treated biweekly with 20 mg/kg alglucosidase alfa. Muscle strength, muscle function, and pulmonary function were assessed every 3-6 months and analyzed using repeated-measures ANOVA. Results: Sixty-nine patients (median age 52.1 years) were followed for a median of 23 months. Muscle strength increased after start of ERT (manual muscle testing 1.4 percentage points per year (pp/y); hand-held dynamometry 4.0 pp/y; both p < 0.001). Forced vital capacity (FVC) remained stable when measured in upright, but declined in supine position (-1.1 pp/y; p = 0.03). Muscle function did not improve in all patients (quick motor function test 0.7 pp/y; p = 0.14), but increased significantly in wheelchair-independent patients and those with mild and moderate muscle weakness.Relative to the pre-treatment period (49 patients with 14 months pre-ERT and 22 months ERT median follow-up), ERT affected muscle strength positively (man