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In this paper, the ordering in concentrated charge stabilized colloidal dispersions is considered. Despite the impressive Bragg reflections obtained for shear ordered dispersions by light (LS), small-angle neutron (SANS), and small-angle X-ray scattering (SAXS), a number of open questions remain. Sheared dispersions are usually ordered in layers. For such systems, two questions arise: (1) What is the structure in a layer? (2) What is the stacking structure perpendicular to the layers? The second question requires a method to determine the structure perpendicular to the layers. Although originally interested only in structural aspects, we were forced to consider different methods. Two methods are treated both applicable to neutron and X-ray scattering from concentrated dispersions. One has been used by physicists and chemists for many years to determine the structure of crystals by sample rotation. In colloid science, we have used it previously in neutron and X-ray scattering. A second method is treated here which can be applied in small-angle scattering from a Couette cell. It gives the scattering intensity in a certain direction without sample rotation. Although very useful with the Couette cell, it cannot be found in any of the well-known references on colloid science. A theoretical explanation and experimental examples obtained by synchrotron X-ray scattering from a Couette cell are given in the paper.

In this contribution small-angle scattering from layered systems is considered. When a colloidal dispersion is stirred it usually decomposes into layers. There are two important questions concerning these layers: What is the structure in a layer? What is the stacking structure between such layers? For concentrated colloidal dispersions both these questions can be investigated by small-angle scattering experiments. It will become apparent that the answer is also important for technical applications. Both a theoretical description as well as an experimental verification are given in the paper.

The present paper is concerned with the structure of dispersions made from charged polymer particles. First, the determination of important properties of single particles is discussed. It follows a typical phase diagram of charge stabilized dispersions. Their structure and possibilities to manipulate the structure are considered in the following sections. For the understanding of scattering experiments, as light scattering (LS), small angle neutron (SANS) and small angle synchrotron x-ray scattering (SAXS) the reciprocal lattice is of fundamental importance. A separate chapter, therefore, is dedicated to it. The application of shear has been found to be a particularly successful method for manipulating the structure of dispersions. It is possible to generate one-dimensional (1D) strings as well as plane (2D) layers which become (3D) crystals with time. The phenomena and structures generated by shear are in part surprising and at present not fully understood.

We report our experience of pacemaker treatment in a premature infant of 832 grams with congenital complete atrioventricular block due to maternal Sjogren's Syndrome. She was delivered by cesarean section at an estimated gestational age of 26 weeks because of fetal bradycardia, decreasing fetal movements and hydrops. Immediate postnatal transesophageal ventricular pacing was not successful, whereas transthoracic pacing with self-adhesive patch electrodes adapted to body size resulted in an effective increase of the infant's heart rate until operative application of temporary epimyocardial pacing wires ensured the external stimulation of the heart.

The influence of shear on the Bragg scattering of concentrated colloidal dispersions made from charged particles is considered in this paper. First, the reciprocal space of a layered sample at rest and under the influence of a disordering torque is considered. Next, the commonly used Couette cell and our disk shear cell are compared in view of the Ewald construction. An introduction of α- and β-rotation axes follows. The first experimental example is concerned with the neutron scattering from a layered colloidal sample at rest. As a second experimental example from the same sample the dependence of synchrotron X-ray scattering on the shear rate is considered. It turns out that the sample does not achieve a microcrystalline state as claimed previously but remains in an orientationally disordered layered state. Finally, the intensity distribution I(l) along the two types of Bragg rods as obtained with remarkable precision by synchrotron X-ray scattering is presented.

In this work the Couette cell is compared with a more recently constructed disk shear cell. There are distinct advantages of the disk over the Couette cell, in particular, when it comes to the determination of the intensity along certain Bragg rods.

Objectives We review the efficacy of oral sugar solutions for treating procedural pain in neonates and address the following questions: Do newborns need analgesic therapy for procedural pain during blood sampling? How do sugars influence pain-reactions of neonates? What is the efficacy of sugar solutions in clinical practice? Methods We searched for relevant articles in the PubMed database from 1990 to September 2000. Results Treatment of procedural pain in newborns is desirable because they are more sensitive to pain than adults, they show marked pain reactions during blood sampling and repeated acute pain in the newborn period results in longterm behavioural changes. Oral sugar solutions have been studied for treatment of procedural pain in neonates. Their initial effect is the result of orotactile stimulation by the intraoral fluid. The orogustatory stimulation by the sweet taste prolongs the effect for up to 10 minutes through endorphin release. In randomized-controlled trials oral sugar solutions (2 ml of 25% sucrose or 30% glucose) reduced pain reactions and crying and attenuated the heart rate increase after capillary and venous blood sampling in term and preterm neonates. They are more effective than traditional calming strategies, like cuddling by parents, use of a pacifier, or breast feeding. Yet, sugar solutions provide no adequate analgesia for more severe pain, e.g. during circumcision. Conclusions Sugar solutions effectively relieve procedural pain during blood sampling in neonates. Additional studies are needed to determine the minimal effective dose and the efficacy and side effects of repeated sugar doses in the same patient.

This paper is concerned with video microscopy, an analytical method of growing importance for the studies of colloid suspensions. Particular emphasis of this work will be laid on the derivation of simple recipes for the computation of static and dynamic pair correlation functions from the microscopic images. The strengths and also the weaknesses of the method will be discussed in detail. We will also present a selection of results gained by this method to demonstrate, that video microscopy is a valuable addition to the well established analytical methods like neutron and laser light scattering in colloid science.

Kossel rings of colloidal dispersions obtained with colloids at rest and under flowing conditions are described. When flowing only Kossel rings of planes with a component in the direction of the flow do not vanish. Compared with the dispersion at rest the number of Kossel rings of the dispersions under flow is reduced. Experimental examples are presented.

Through modern reproductive techniques Hellin's rule, approximating multiple births, is no longer applicable. Consequently perinatal centres have been facing an increasing number of multifoetal pregnancies during the last 15 years. The foetal outcome of 81 multifoetal pregnancies, delivered between January 1, 1980 and June 30, 1995 at the Klinik und Poliklinik fur Frauenheilkunde und Geburtshilfe im Klinikum Grosshadern, Munich, Germany, illustrates both the risk as well as the chance for healthy survival under the applied management protocol. Mean gestational ages at delivery were 221 days (31 + 4 weeks) for triplets, 213 days (30 + 3 weeks) for quadruplets and 200 days (28 + 4 weeks) for quintuplets, mean birth weight was 1400 g, 1100g and 1080 g respectively. 96.4% of the triplets survived (188/195), 70% (137/195) could be discharged home without medical problems. 98.1% (51/52) of the quadruplets and 80% (12/15) of the quintuplets survived, 67% (35/52) and 53% (8/15) respectively without health impairment. Respiratory distress syndrome, intracranial hemorrhage, retinopathy of prematurity, persistent Ductus arteriosus, necrotising enterocolitis and hydrocephalus are primary causes of neonatal morbidity. Serious neurological sequels such as developmental retardation and cerebral palsy were noted in 4 (6%) and 5 (8%) of the quadruplets and quintuplets. Health impairment and mortality show a clear association to gestational age under 30 weeks but do not differ significantly in frequency or distribution from single or twin neonates of equal gestational age and management. A threshold regarding prognosis seems to be the number of foetuses 4 versus 5 and the gestational age before or after 210 days (30 weeks). Before 32 weeks of gestation the indication for delivery was most often due to foetal problems. With progressing duration of pregnancy the risk for maternal complications rises and may warrant termination of pregnancy in the face of a usually uncomplicated postnatal course of foetuses born after 32 weeks of gestation at a perinatal centre. The presented data suggest that an individually adapted, liberal indication for delivery by caesarean section after 32 weeks is the safest management scheme for mother and foetuses.

Das Management der Hyperbilirubinamie bei reifen gesunden Neugeborenen ohne Hamolyse ist noch immer eine Angelegenheit von Interesse wegen Haufigkeit und Nebenwirkungen der Phototherapie, wie die Trennung der Mutter von ihren Kindern. Neue Daten uber Bilirubin und das Outcome der Kinder in dieser Gruppe in bezug auf Kernikterus, intellektuelle, neurologische und Horstorungen rechtfertigen ein weniger aggressives Management und Toleranz hoherer Bilirubingrenzwerte. Die Arbeitsgemeinschaft Berliner Neonatologen schlos sich den neuen Richtlinien der ”American Academy of Pediatrics„ an, Phototherapie erfolgt ab einem Gesamtbilirubin von 340 μmol/l (20 mg/dl) im Alter von > 72 h und 310 μmol/l (18 mg/dl) im Alter von 48–72 h. Die Phototherapiehaufigkeit konnte so von 9,7 auf 2,5% und die Haufigkeit von Blutentnahmen von 27,0 auf 14,5% gesenkt werden.

Mortality, Mode of Delivery, Pneumothorax and Intracranial Haemorrhage in 859 Very Low Birth-Weight Infants Between 1984-1992: In a retrospective study we investigated the mortality and the most important complications of all very low birth-weight infants (VLBW; ≤ 1500 g and/or ≤ 32 weeks) born with vital signs between 1984 and 1992 at the Klinikum Grosshadern, Munich University Hospital. During this period 859 premature infants fulfilled the entrance criteria. The perinatal mortality rate was 174/859 infants (20%). During the study period the mortality rate dropped significantly from 25% (1984-1986) to 15% (1990-1992). Premature infants born after 26 gestational weeks showed the most significant decrease in mortality. Excluding non viable infants with extreme immaturity (< 24 weeks of gestation) or lethal malformations, the mean corrected mortality rate was 11 %, decreasing over the years from 16% (1984-1986) to 5% (1990-1992). Caesarean section was performed in 70% of all children (602/859), vaginal delivery in 28% (239/859), delivery by forceps in 1% (7/859), and the mode of delivery was not clearly registrated in 1% (11/859). The incidence of Caesarean section increased significantly from 55% (1984-86) to 79% (1990-92). Evaluating the mode of delivery in relation to mortality, a significant difference was found between the infants delivered vaginally (40%, 95/239) and those delivered by Caesarean section (11 %, 67/602). This improved survival after Caesarean section was statistically significant for the group with a birth weight of less than 1500 g. The rate of pneumothorax also declined significantly from 19% to 9%. The rate of intracranial haemorrhage (ICH) remained almost constant during these years, but the incidence of ICH grade 3 and 4 decreased from 15% (1984-1986) to 6% (1990-1992). Probably because of improved antenatal care and the progress in neonatal intensive care, the chance of survival for VLBW infants has substantially improved over the last decade. Estimations of the prognosis of VLBW infants based on data from the 1980 s are out of date.

In the last three years an interdisciplinary ECMO (extracorporeal membrane oxygenation) team has been set up at the Free University of Berlin in the Steglitz clinic. With this form of management, newborns only a few hours or days old who present with pulmonary failure can temporarily be managed with extracorporeal oxygenation until normal lung function is restored. The set up of this ECMO team, starting with experimental training in animal models, to the bedside clinical use is discussed. The following presentation of the first four cases managed here with ECMO aims to clarify the problems which may be encountered as well as amplifying its use as a life-saving measure.

Before the entry criteria for extracorporeal membrane oxygenation (ECMO) are met, newborns may require aggressive mechanical ventilation which may result in lung injury. The question arises whether the presence of a pneumothorax in these infants plays a role in the prognosis. Of the 21 newborns transferred to our hospital for ECMO, 8 were treated with ECMO. 9 of the 21 newborns developed a pneumothorax with conventional ventilation and 6 of these 9 newborns subsequently required ECMO. Infants who developed a pneumothorax but did not meet ECMO criteria and remained in the oxygenation index (01) range between 25 and 40 for more than 2 days had a poorer prognosis. If adequate oxygenation cannot be attained with acceptable mechanical ventilation and a more aggressive ventilation results in a pneumothorax, ECMO should be considered even if the oxygenation index is below 40.

Experimental and computer simulation values of the zeroth and second moments of the depolarized Rayleigh and Raman spectra of N2 are reported. A wide range of density at a fixed temperature of 50°C was covered. The density dependence of the spectral moments is due primarily to interaction-induced effects which are successfully modelled here assuming a first-order dipole-induced-dipole mechanism. The agreement between experiment and simulation is good, with the exception of spectra at state points where it appears that the ‘distinct’ term (i.e., the contribution from orientationally correlated pairs of molecules) is significant.

In this paper, scattering from Bragg rods is considered. For layered colloidal structures, the intensity along Bragg rods reflects the stacking order of the layers. It is described how the small angle neutron (SANS) scattering intensity can be used to characterize layered systems. Scattering examples are presented for colloidal layers at rest and under sheared (flowing) conditions.

Fruhgeborene mit einem Geburtsgewicht von weniger als 1500 g machen nur ungefahr 1% der Lebendgeborenen aus, sind aber fur bis zu 85% der neonatalen Mortalitat verantwortlich. Naturgemas steigt die Mortalitatsrate mit fallendem Geburtsgewicht. Dies gilt auch fur Komplikationen, die im Verlauf der ersten Lebenswochen auftreten konnen wie z.B. Hirnblutungen, Retinopathie oder Pneumothorax. Verlasliche und aktuelle Zahlen uber den derzeitigen Stand der Haufigkeit dieser Komplikationen bzw. der auf das Gestationsalter bezogenen Mortalitat sind fur den Entscheidungsprozes beim Auftreten von Komplikationen wahrend einer Schwangerschaft von ausschlaggebender Bedeurung. Der Geburtshelfer mus auch fur die Beratung von Schwangeren wissen, welche Komplikationen bei einem Fruhgeborenen auch unter optimalen Bedingungen auftreten konnen.

Neonatal drug utilization in very premature infants (gestational age (GA) 24-29 weeks), requiring intubation and mechanical ventilation at birth was registered as part of a multicenter controlled clinical trial of high-dose versus low-dose bovine surfactant (initial doses 100 mg/kg birth weight (b.w.) versus 50 mg/kg b.w.). Drug utilization during 4 weeks after birth was analyzed in 164 infants (mean GA 27.2 +/- 1.2 (SD) weeks, b.w. 970 +/- 145 g (SD)). More than half of the study infants received antibiotics (98.8%), sedatives and analgesics (91.5%), sodium bicarbonate (78%), solutions for volume replacement (62.8%), methylxanthines (56.7%) and catecholamines (52.4%). It may be concluded that the pattern of drug usage indicates a high incidence of proven or suspected infections and circulatory and respiratory disorders reflecting the high-risk state of study infants.

Weight, extracellular volume (ECV; distribution volume of sucrose) and renal function were studied in 13 preterm infants at birth (age 6 h (2-12); median, range) and again when postnatal weight loss exceeded 5% of birth weight (age 84 (64-97) h). Gestational age was 28 (26-32) weeks, and birthweight was 1,170 g (810-1,455). The infants were nursed in incubators and mechanically ventilated. Fluid therapy allowed a weight loss of up to 10% of birthweight. Body weight decreased significantly from 1,101 +/- 202 g at birth to 1,016 +/- 198 g at day 3 and ECV from 499 +/- 155 ml to 413 +/- 118 ml. Mean weight loss of 85 +/- 50 g was the same as mean ECV loss of 86 +/- 48 ml, suggesting that postnatal weight loss is water loss from the ECV. Weight loss was preceded by a marked increase in diuresis, exceeding fluid intake on day 2. Creatinine clearance did not change. The increased urine output led to a significant increase of sodium excretion without inducing hyponatremia but resulted in an isotonic reduction of ECV.

Le but de cette etude est de montrer que des phenomenes electrocinetiques, comme l'electrophorese et l'electroosmose peuvent etre traites de maniere symetrique et mesures par diffusion de lumiere

Nach Berichten uber 17 Falle von infantiler myoklonischer Encephalopathie in der Literatur wird uber 4 weitere Patienten mit dieser Erkrankung berichtet. Es handelt sich um eine Erkrankung des spaten Sauglings- und Kleinkindesalters, die akut beginnt und die durch Myokloni der gesamten Willkurmuskulatur, durch heftige, sakkadierte Augenbewegungen (Opsoklonus) und durch gesteigerte Irritabilitat gekennzeichnet ist. EEG und Liquor cerebrospinalis sind nicht pathologisch verandert. Pathologisch-anatomisch liegen die Veranderungen in den Purkinjezellen und im Nucleus dentatus des Kleinhirns sowie in der weisen Substanz des Groshirns. Eine Behandlung mit Corticoiden oder ACTH kann die Symptome der Erkrankung rasch beheben, mus jedoch meist uber Monate oder Jahre durchgefuhrt werden und scheint haufige Spatschaden auf motorischem, intellektuellem und sprachlichem Gebiet nicht verhindern zu konnen. Unbehandelt verlauft die Erkrankung uber lange Zeit mit Remissionen und meist infektbedingten Exacerbationen. Es werden die atiologischen Moglichkeiten (von denen eine immunologische Reaktion auf verschiedenartige Antigene am wahrscheinlichsten ist) sowie die Tatsache diskutiert, das ein identisches Krankheitsbild in Verbindung mit einem Neuroblastom vorkommen kann.

Dynamic light scattering from two liquidlike ordered latex suspensions with particle diameters 85 and 109 nm, as well as the scattering from a 4:1 mixture of these suspensions are investigated. Both the static structure factor SM(K) and the intermediate scattering function FM(K,τ) of the mixture strongly deviate from those of the neat suspensions at low scattering angles. This discrepancy is discussed in terms of an incoherent light scattering contribution due to scattering‐power polydispersity of the mixture. Our experiments confirm theoretical expressions recently derived by Pusey et al.

Nach der Hellinschen Hypothese aus dem Jahre 1895 ist das Auftreten von Mehrlingsschwangerschaften ein seltenes Ereignis. Durch die verschiedenen, derzeit praktizierten Verfahren der Sterilitatsbehandlung nach hormonaler Stimulation steigt jedoch die Inzidenz von Mehrlingsschwangerschaften deutlich an.

Often in spectroscopic line shape experiments one is interested in the line width of a Gaussian or Lorentzian profile. We want to call attention to a simple numerical procedure which allows a significant signal to noise improvement in such studies.