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Introduction According to the Embryo Protection Act, the selection of embryos with the greatest potential for successful implantation in Germany must be performed in the pronucleus stage. The main aim of this study was to identify morphokinetic parameters that could serve as noninvasive biomarkers of blastocyst quality in countries with restrictive reproductive medicine laws. Materials and Methods The sample comprised 191 embryos from 40 patients undergoing antagonist cycles for intracytoplasmic sperm injection. Blastocysts were cultured in an EmbryoScope chamber and video records were validated to determine the post-injection timing of various developmental stages, cleavage stages, and blastocyst formation. The Gardner and Schoolcraft scoring system was used to characterize blastocyst quality. Results Morphokinetic data showed that the zygote diameter and total cytoplasmic volume were significantly different between good and poor blastocysts quality groups, where zygotes, which formed better blastocyst quality, had smaller diameter and smaller total cytoplasmic volume. Zygotes with more rapid pronuclear disappearance developed in better-quality blastocysts. Differences between good- and poor-quality blastocysts were also observed for late-stage parameters and for the spatial arrangement of blastomere where tetrahedral embryos more frequently forming good-quality blastocyst compare to the non-tetrahedral. Conclusions The study findings could be used to enhance embryo selection, especially in countries with strict Embryo Law Regulations. Further studies, including those in which the implantation potential and pregnancy rate are considered, are warranted to confirm these preliminary results.

Resorption of magnesium-based alloy bioabsorbable screws produces hydrogen gas, which can be mistaken as a sign of infection and may affect the physis or fixed bone fragment.We evaluated the temporal and spatial occurrence of gas and the occurrence of a breakage of the fixed bone fragment or screw following magnesium screw fixation.Radiographs of paediatric patients treated with magnesium screws were retrospectively reviewed. Temporal occurrence and distribution of gas in the bone, the physis and soft tissues, breakage of the screw or fixed bone fragment and joint effusion were assessed.One hundred and three radiographs in 35 paediatric patients were reviewed (mean age: 10.6 years). Follow-up ranged from 1 to 730 days. Gas in the bone increases up to week 5, remains constant up to week 16 and then decreases. Gas in soft tissues, intra-articular gas and joint effusions gradually reduce over time. In 1/23 (4.3%) patients with an open physis, gas intrusion into the physis occurred. Breakage of the bone fragment fixated by the screw was observed in 4/35 (11.4%) patients within the first 6 weeks. Screw breakage was observed in 16/35 (45.7%) patients, with a median time to first detection of 300 days.Gas bubbles in bone and soft tissue are normal findings in the context of screw resorption and should not be confused with soft-tissue infection or osteomyelitis. Gas is rarely visible in the physis. Breakage of the fixed bone fragment and/or screw can occur.

Background: Fetoscopic endoluminal tracheal occlusion (FETO) improves lung maturation in severe cases of congenital diaphragmatic hernia (CDH) but it does not ameliorate lung compression by herniated abdominal organs. Surgically opening the fetal abdomen (abdominal decompression [AD]) reduces the intrathoracic pressure by diverting the abdominal organs into the amniotic cavity-a probable causal therapy for lung hypoplasia and pulmonary hypertension in CDH. Open surgical abdominal decompression has been reported: we describe a minimally invasive approach in an ovine model of CDH as a probable fetoscopic intervention. Materials and Methods: Eight fetuses were included, 2 were kept as HEALTHY controls. A CDH (left side, liver down) was created by open fetal surgery at midgestation in 6 fetuses, 2 were taken as CDH controls. Fetoscopic abdominal decompression (fAD) was performed 21 days later in 4 animals. The fetuses were retrieved at the end of gestation and evaluated by lung stereology. Results: fAD led to a near total evacuation of the thoracic cavity in 2 of the 4 animals. Fetuses with CDH had a lower total volume and fraction of alveolar air space, a lower volume fraction of the parenchyma, and an increase of the volume fraction of the alveolar septa and atelectasis, as well as an increased mean thickness of alveolar septa compared with HEALTHY fetuses. Fetuses treated with abdominal decompression showed an improvement of stereological parameters. Conclusions: In spite of relevant limitations (pilot study, small groups, spontaneous closure of the abdominal incision) we were able to demonstrate that abdominal decompression for CDH can be performed by fetoscopy. Our results support the hypothesis of causally improving lung development by abdominal decompression, thus implying increased survival in extreme cases of CDH. A refinement of the fetoscopic techniques and direct comparison to FETO appears warranted.

Background: The resorption of magnesium-based alloy bioabsorbable screws results in the release of hydrogen gas, which can mimic infection and enter the growth plate. The screw itself and the released gas may also affect image quality. Objective: The evaluation of magnetic resonance imaging (MRI) findings during the most active phase of screw resorption is the objective, with particular focus on the growth plate and to assess for the presence of metal-induced artifacts. Material and Methods: In total, 30 prospectively acquired MRIs from 17 pediatric patients with fractures treated with magnesium screws were assessed for the presence and distribution of intraosseous, extraosseous, and intra-articular gas; gas within the growth plate; osteolysis along the screw; joint effusion; bone marrow edema; periosteal reaction; soft tissue edema; and metal-induced artifacts. Results: Gas locules were found in the bone and soft tissues in 100% of the examinations, intra-articular in 40%, and in 37% of unfused growth plates. Osteolysis and the periosteal reaction were present in 87%, bone marrow edema in 100%, soft tissue edema in 100%, and joint effusion in 50% of examinations. Pile-up artifacts were present in 100%, and geometric distortion in 0% of examinations. Fat suppression was not significantly impaired in any examination. Conclusions: Gas and edema in the bone and soft tissues are normal findings during the resorption of magnesium screws and should not be misinterpreted as infection. Gas can also be detected within growth plates. MRI examinations can be performed without metal artifact reduction sequences. Standard fat suppression techniques are not significantly affected.

Separation of stable emulsions produced from chemical enhanced oil recovery (CEOR) in a brownfield production system using conventional 3-phase separators is almost impossible, requiring large quantities of chemical demulsifiers to meet oil production specifications. A new and novel high-voltage high-frequency (HVHF) electro-coalescence (EC) technology has been identified as potential method to enhance separation of EOR produced fluid for improving CEOR implementation feasibility. This paper aims to present results and findings from the recent EC technology development against success criteria and parameters associated for fast-track field application. Electrostatic coalescers are used as an emulsion breaker, crude dehydrator or desalter in production systems and refineries. However, significant developments are required to use this EC technology as a potential treatment technology for tight emulsions/rag layers in CEOR applications. A new prototype of Inline EC was developed and tested in a batch test setup to evaluate the separation efficiency using real crude-brine samples and a cocktail of alkaline-surfactant-polymer (ASP) chemicals. The sensitivities of separation efficiency to different water cut, demulsifier concentration, EC voltage/exposure time, concentrations of alkaline, surfactant and polymer in the brine were measured and optimal process conditions were assessed. The results and findings were evaluated based on defined success criteria and parameters associated with separation efficiency such as volume fractions of the emulsion, oil-in-water (OIW) and water-in-oil concentrations (WIO), respectively. On one of PETRONAS CEOR field case study, the test results show that EC reduced 90% of the tight emulsion. In conclusion, EC leads to a substantial improvement in separation efficiency relative to the case without EC for water cuts below the inversion point. It is also found that the EC treatment without added demulsifier is equally effective in breaking the emulsion as adding a demulsifier without EC treatment, and that EC can potentially minimise or eliminate the application of demulsifiers in the production system.

Study question Does the total cytoplasmic volume (TCV) of the zygote and time of pronuclei disappearance (tPNf) affect blastocyst development potential and blastocyst quality? Summary answer The total cytoplasmic volume of zygote and the time of pronuclei disappearance strongly affect blastocyst development as well as blastocyst quality. What is known already Extended embryo culture with blastocyst transfer is considered a useful method for selecting embryos with a high implantation potential. One of the main concerns in the German Embryo Protection Act is that the choice of embryos that have a high potential for successful implantation must be made at the pronucleus stage. The introduction of time-lapse technology enabled comprehensive information regarding the morphology and kinetics of the embryo. Although for the past years, strong correlations between embryo morphokinetics and positive outcomes have been demonstrated, some disagreement concerning the wide application of these parameters into an early-stage embryo selection is still present. Study design, size, duration The injection time of ICSI was designated as “time zero”, and computer software was used to calculate the time frame between the injection and the moment of pronuclei disappearance (tPNf). The total cytoplasmic volume was calculated 16–18 h after injection based on manually drawn diameters of the zygotes, by the computer. Obtained measurements were later associated with the blastocyst formation potential as well as with blastocyst quality. Participants/materials, setting, methods A total of 187 oocytes from 34 patients undergoing the antagonist cycle for ICSI treatment were evaluated. All blastocysts were cultured in Embryoscope™ according to the manufacturer’s specifications (Vitrolife, Sweden). The Gardner and Schoolcraft scoring system was used to describe blastocyst quality. Statistical analyses were performed using IBM SPSS version 24. Data were reported as median and range. Differences between groups were tested using the Mann-Whitney U test. Statistical significance was defined as p Main results and the role of chance Obtained data showed that the total cytoplasmic volume values were significantly higher in zygotes that reached the blastocyst stage compared with those that did not [708376,268µm³ (560564,412µm³ - 838602,605µm³) vs 674349,917 (415749,353- 823640,638) respectively; p Limitations, reasons for caution The limitation of the presented study was that due to the double-embryo transfer correlation between morphokinetic parameters and pregnancy rate was not possible to be calculated. Further research should link these morphokinetic parameters with pregnancy rate and live birth rate as well. Wider implications of the findings: The potential of the present findings is considerable, especially for countries with strict Embryo Law Regulation. Obtained results might be highly useful for selecting embryos with high implantation potential. In addition, the present work illustrates the possibility of additional information that can potentially be incorporated into an embryo classification model. Trial registration number Not applicable

Study question Does the spatial arrangement of blastomeres and the start of blastulation affect blastocyst quality? Summary answer Better blastocyst quality is associated with the spatial arrangement of the embryo and the shorter time frame of blastulation (cavitation). What is known already The ability to select the human embryo with the highest implantation potential remains one of the greatest challenges in the management of In Vitro Fertilization patients. Several publications have proposed that additional morphological evaluations of blastomere arrangement and the dynamics of late-stage embryonic divisions might be a useful non-invasive way for embryo selection. In the last decade, the introduction of time-lapse technology enables continuous monitoring of embryo development, which leads to better outcomes than a selection based on the traditional morphology assessment. Study design, size, duration The spatial arrangement was defined as tetrahedrally if the cleavage planes were perpendicularly orientated, while embryos with rather parallelly orientated cleavage axes were considered as non-tetrahedral embryos. The injection time of ICSI was designated as “time zero” (t0), and EmbryoViewer software was used to calculate the time duration between injection and start of blastulation (cavitation). Obtained results were later correlated with the embryo’s capability to form a blastocyst as well as with blastocyst quality. Participants/materials, setting, methods A total of 195 oocytes from 40 patients undergoing the antagonist cycle for ICSI treatment were evaluated. All blastocysts were cultured in Embryoscope™ according to the manufacturer’s specifications (Vitrolife, Sweden). The Gardner and Schoolcraft scoring system was used to describe blastocyst quality. Statistical analyses were performed using IBM SPSS version 24. Data were reported as median and range. Differences between groups were tested using the Mann-Whitney U test. Statistical significance was defined as p Main results and the role of chance Obtained data showed that 83.6% (61/73) of embryos with tetrahedral arrangement formed blastocysts compared to 42.4% (50/116) of embryos with the non-tetrahedral arrangement (p Limitations, reasons for caution The limitation of the present study was that due to the double-embryo transfer correlation between those morphokinetic parameters and pregnancy rate can not be calculated. Further research should link these morphokinetic parameters with pregnancy rate and live birth rate as well. Wider implications of the findings: The potential of our findings is considerable, especially for countries with strict Embryo Law Regulation. Obtained results might be highly useful for selecting embryos with high implantation potential. In addition, the present work illustrates the possibility of additional information that can potentially be incorporated into an embryo classification model. Trial registration number Not applicable

This prospective study was designed to investigate whether anti-Müllerian hormone (AMH) levels are associated with the presence of multiple pronuclei in zygotes as well as with the ovarian response, fertilization rate and pregnancy outcome in ICSI cycles. A total of 413 patients undergoing ICSI cycles were included in the study. The assessment included 3084 MII oocytes. Serum AMH measurements were performed at the first initial presence of the patient. The outcome measures were the presence of multiple pronuclei (PN), a number of retrieved oocytes, number of mature/immature oocytes, fertilization rate and clinical pregnancy. Obtained results showed a statistically significant correlation between AMH levels and maternal age, the number of follicles, the number of cumulus-oocyte complexes, mature and immature oocyte, fertilization rate and pregnancy rate. Linear regression analysis showed that AMH significantly correlates with the presence of multiple pronuclei in the zygote. The further analysis confirmed that the number of zygotes with the presence of multiple pronuclei increased when AMH levels were higher. This is the first examination of the prognostic value of the serum AMH on the presence of multiple pronuclei in the zygote and our data in the preliminary study suggest that AMH levels could be used as a predictive marker.

Summary The aim of the review was to evaluate the routine use of sternal elevation techniques (SETs) during minimally invasive repair of pectus excavatum (MIRPE, the Nuss procedure). We performed a review of the literature between January 1998 and September 2018 with focus on different methods of SET during MIRPE. Reported effects and side effects were evaluated and compared with our own experience concerning the routine use of the vacuum bell for sternal elevation during MIRPE during the last 13 years. SET is more often used in adult patients than in adolescents. SET improves visualization and safety of MIRPE. Advancement of the pectus introducer, retrosternal dissection and placement of the pectus bar are easier. The risk of cardial and/or pericardial lesion is reduced significantly. Different types of retractors, a crane combined with a wire and/or customized hooks are reported to be used as SET. Furthermore, routine use of a subxiphoid incision is reported. However, more technical equipment, and in some SETs additional incisions are necessary. In contrast, no additional skin incision is necessary for the vacuum bell. The routine intraoperative use of the vacuum bell was safe and effective in 131 patients. It facilitates the retrosternal dissection and the insertion of the pectus bar like other SETs. Besides a temporary mild hematoma, no relevant side effect was observed. In conclusion, an increasing number of authors report on the routine use of SET during MIRPE to improve safety of the procedure. We recommend the routine intraoperative use of the vacuum bell during MIRPE.

Introduction Spaced learning has been shown to be superior in complex motor skill acquisition like laparoscopic suturing and knot tying. By using a pre–post follow-up design, the aim of the study was to evaluate the long-term impact of implementation of the spaced learning concept in laparoscopic training. Materials and Methods To evaluate the effectiveness of spaced learning, subjects were asked to perform four surgeon's square knots on a bowel model within 30 minutes—prior and after 3 hours of hands-on training. To examine the long-term skills, the same students were asked to perform a comparable, but more complex, task (four slip knots in a model of esophageal atresia) 12 months later as follow-up measurement. Total time, knot stability (evaluated via tensiometer), suture accuracy, knot quality (Muresan scale), and laparoscopic performance (Munz checklist) were assessed. Moreover, motivation was accessed using Questionnaire on Current Motivation. Results Twenty students were included in the study; after simple randomization, 10 were trained using the “spaced learning” concept and 10 via traditional methods. Both groups had comparable baseline characteristics and improved after training significantly, regarding all aspects assessed in this study. Subjects that trained via spaced learning were superior in terms of speed (p = 0.021), knot quality (p = 0.008), and suture strength (p = 0.003). Additionally, spaced learning significantly decreased anxiety (p = 0.029) and probability of success (p = 0.005). Conclusion The spaced learning concept is very suitable for long-term complex motor skill acquisition, like laparoscopic suturing and knot tying. It is superior to conventional training regarding speed and, most importantly, knot quality and stability, resulting in improved confidence and motivation. Thus, we strongly recommend to incorporate the spaced learning concept into training courses and surgical programs.

It is difficult to predict the risk of mortality in necrotizing enterocolitis (NEC). This study aimed at identifying risk factors for severe NEC (Bell stage III) and mortality in preterm children with NEC. In this multicenter retrospective study, we analyzed multiple data from 157 premature children with confirmed NEC in the period from January 2007 to October 2018. We performed univariate, multivariate, stepwise logistic regression, and receiver operator characteristics (ROC) analyses. We were able to demonstrate that low Apgar scores (notably at 1′ and 5′), low hemoglobin concentration (Hgb), and high lactate level at disease onset and during disease correlated with NEC severity and mortality (P Conclusion: Low Apgar scores, low Hgb, high lactate levels, and the presence of CHD or PDA correlated with severe NEC or mortality in children with NEC. What is Known:• It remains difficult to predict which infant that suffers from necrotizing enterocolitis at risk of death.• Several clinical and laboratory parameters tools to predict fatal outcome in NEC. What is New:• The following laboratory parameters were associated with the risk of death from NEC: Hemoglobin concentration, base excess and lactate level.• The following clinical variables were associated with the risk of death from NEC: Apgar scores, as well as the presence of congenital heart disease and patent ductus arteriosus.

As many meta-analyses comparing pediatric minimally invasive to open surgery can be found in the literature, the aim of this review is to summarize the current state of minimally invasive pediatric surgery and specifically focus on the trends and developments which we expect in the upcoming years. Print and electronic databases were systematically searched for specific keywords, and cross-link searches with references found in the literature were added. Full-text articles were obtained, and eligibility criteria were applied independently. Pediatric minimally invasive surgery is a wide field, ranging from minimally invasive fetal surgery over microlaparoscopy in newborns to robotic surgery in adolescents. New techniques and devices, like natural orifice transluminal endoscopic surgery (NOTES), single-incision and endoscopic surgery, as well as the artificial uterus as a backup for surgery in preterm fetuses, all contribute to the development of less invasive procedures for children. In spite of all promising technical developments which will definitely change the way pediatric surgeons will perform minimally invasive procedures in the upcoming years, one must bear in mind that only hard data of prospective randomized controlled and double-blind trials can validate whether these techniques and devices really improve the surgical outcome of our patients.

Background & AimsHirschsprung’s disease (HSCR) is a congenital intestinal motility disorder defined by the absence of enteric nervous cells (ganglia). The development of HSCR-associated enterocolitis remains a life-threatening complication. Absence of enteric ganglia implicates extramural innervation of acetylcholine-secreting (cholinergic) nerve fibers. Cholinergic signals have been reported to control excessive inflammation, but the impact on HSCR-associated enterocolitis is unknown.MethodsWe enrolled 44 HSCR patients in a prospective multicenter study and grouped them according to their degree of colonic mucosal cholinergic innervation using immunohistochemistry. The fiber phenotype was correlated with the tissue cytokine profile as well as immune cell frequencies using quantitative reverse-transcribed real-time polymerase chain reaction (qRT-PCR) of whole colonic tissue and fluorescence-activated cell sorting (FACS) analysis of isolated colonic immune cells. Fiber-associated immune cells were identified using confocal immunofluorescence microscopy and characterized by RNA-seq analysis. Microbial dysbiosis was analyzed in colonic patient tissue using 16S rDNA gene sequencing. Finally, the fiber phenotype was correlated with postoperative enterocolitis manifestation.ResultsWe provided evidence that extrinsic mucosal innervation correlated with reduced interleukin (IL)-17 cytokine levels and T-helper-17 (Th17) cell frequencies. Bipolar CD14high macrophages colocalized with neurons and expressed significantly less interleukin-23, a Th17-promoting cytokine. HSCR patients lacking mucosal cholinergic nerve fibers showed microbial dysbiosis and had a higher incidence of postoperative enterocolitis.ConclusionThe mucosal fiber phenotype might serve as a new prognostic marker for enterocolitis development in HSCR patients and may offer an approach to personalized patient care and new future therapeutic options. (www.clinicaltrials.gov accessing number NCT03617640)

We report the case of a 4-year-old female infant who developed ongoing deep dermal necrosis of the bilateral legs after jellyfish contact in Thailand. Stepwise radical debridement and vacuum assisted wound therapy seemed to be an effective strategy to prevent progressive soft tissue loss.

High temperature electronics are used in a wide range of applications especially in extreme environments. There is a clear trend in aircrafts to have electrical controls mounted closer to the engine [1]. In cars more and more mechanical and hydraulic systems are replaced by electromechanical or mechatronic systems [2]. They are getting closer to high temperature environments like the engine or brakes. To its nature, avionic and automotive applications require predictable, highly reliable systems. Because elevated temperatures will increase the speed of material aging, the combination of high operation temperatures and high reliability is quite challenging. This applies in particular to interconnect materials such as solders or bonding wires.

Emulsion droplet formation occurs in milliseconds to seconds when emulsifier adsorption is often not yet completed, therewith allowing coalescence to take place. Because of these short time-scales, it is difficult to quantify adsorption and coalescence during processing. A microfluidic device can be used to measure coalescence shortly after droplet formation in laminar flow, and this device was used to assess coalescence of oil-in-water emulsions stabilised with dairy proteins (β-lactoglobulin, whey protein isolate, and oxidised whey protein isolate). Different microfluidic designs were used to vary the protein adsorption time prior to droplet collision. Coalescence stability depended on protein concentration (0.0002–0.02 wt %) and adsorption time (11–173 ms): emulsion droplets were stable at low protein concentrations (as low as 0.005 wt % β-lactoglobulin), as long as the time allocated for protein adsorption was sufficient (in this case 31 ms). Protein type was also important for coalescence stability: emulsions stabilised with whey protein isolate were less stable than those with β-lactoglobulin, and coalescence stability further decreased upon protein oxidation. Regarding the effect of pH (3.0–8.0), coalescence stability was lowest around the protein's isoelectric point. With the coalescence channel we demonstrated the importance of adsorption time and interface composition for coalescence stability at low protein concentrations. Coalescence can be measured at small time-scales and in high detail since coalescence measurements are decoupled from droplet formation. The microfluidic coalescence channel can be used as an analytical tool to gain better understanding of fluid interface stabilisation during emulsification, and to develop emulsion formulations ab initio.

This is the cumulative technical report on the operative procedures and limitations of fetoscopic bag insertion, intestinal bag placement, and bag fixation to the fetus in a series of pilot studies in an ovine model for prenatal treatment of gastroschisis. In 24 German blackhead sheep, a surgically created gastroschisis was managed by fetoscopic placement of the extruded intestines into a bag. The bag was then fastened onto the fetal abdominal wall. Different materials (sterile gloves, latex condoms, laparosopic retrieval bags) and different fixation techniques (laparoscopic staplers, interrupted and continuous sutures) have been examined. The fetuses were retrieved and evaluated at the end of gestation. Uterine bag insertion was successful in 15 of 24 (62.5%) and intestinal bag placement in 10 of 15 available fetuses (66.6%). The main factor limiting fetoscopic procedures was chorioamniotic separation (CAS). Sterilized condoms provided the most appropriate type of bags and the V-Loc™ running suture, the most expedient type of fixation, which was achieved in 9 of the 10 fetuses (complete = 2, partially = 7) by using a three port access (5 mm and 2 × 3 mm). All bags were encountered completely or partially dislocated from the fetus at the end of gestation. Fetoscopic intestinal bag placement and fixation in gastroschisis technically demanding. None of the evaluated techniques led to permanent anchorage of the bag to the fetus. The development of specially designed instruments, bags and fixation methods is required to optimize this approach.

Desulfation of seawater before injection is required to control reservoir souring and scale formation. For this task, operators use nanofiltration (NF) membranes in sulfate removal units (SRUs). The tendency of the membranes to foul is a key operational challenge. To overcome fouling, frequent chemical cleaning is required. An additional constraint for SRUs is that the amount of treated water cannot be increased easily as a higher water output results in an even faster fouling of membranes. In this paper, we describe a method to enhance permeate flux and fouling resistance of desulfation membranes. The enhancements are achieved by modifying the active layer of commercially available NF membranes using a permanent coating that increases hydrophilicity while retaining the high surface charge characteristic of NF membranes. We report the results of a six-month field trial with the coated membranes. The test was executed at the Seawater Desalination Test Facility in Port Hueneme, California using 2.5" dia. membrane modules. The test skid contained two different parallel flow lines with a stack of six coated 2.5" dia. membranes in series, and an uncoated 2.5" membrane for reference. The results show a 25% higher permeate flux for the coated membranes compared to the uncoated membrane at the same transmembrane pressure. Sulfate rejection was unchanged for both coated and uncoated membranes during the entire duration of the test. The coated membrane also showed a lower fouling rate than the uncoated membrane. The time between cleaning events increased by ∼ 38 % for the coated membranes as compared to the uncoated membrane, and the coated membrane processed ∼ 63 % more permeate before cleaning was required. Preliminary results also indicate an enhanced chlorine tolerance of the coated membranes of at least 3000 ppm-h under continuous chlorination at ∼ 1 ppm. The impact of the coating on the economics of SRU operations will be discussed in the paper. The results presented in this paper demonstrate that performance and operability of SRUs can be significantly enhanced by a newly-developed coating, and that a significant reduction in the lifecycle cost of SRUs can be achieved.

Silver (or copper) sintering is nowadays the best choice for power electronics systems with high requirements on reliability, lifetime and application temperature. Especially SiC power modules can only achieve a peak performance together with sintered interconnects. Due to the higher melting temperature and better mechanical properties of silver or copper compared to soft-solder alloys, sintering is used as interconnect material in power modules. But the sintering process itself requires a high pressure up to 30 MPa onto the devices and the process itself is more cost-intensive. To achieve an economical process and make sintering worthwhile to invest, a high yield as a result of a stable process is needed. The idea of rate-controlled sintering (RCS) is a novel approach to make the sintering process robust and profitable. It improves the mechanical properties of sintered die-attach interconnects and decrease their deviation by using vacuum and nitrogen to control the different stages of the sintering reaction. Within this paper the mechanisms of sintering will be introduced, on which the idea of RCS is founded on. A case-study will be presented to demonstrate how rate-controlled sintering works, how it can improve the shear-values of die-attaches and lower die shear deviation.

A software prototype for dynamic route planning in the travel industry for cognitive cities is presented in this paper. In contrast to existing tools, the prototype enhances the travel experience (i.e., sightseeing) by allowing additional flexibility to the user. The theoretical background of the paper strengthens the understanding of the introduced concepts (e.g., cognitive cities, fuzzy logic, graph databases) to comprehend the presented prototype. The prototype applies an instantiation and enhancement of the graph database Neo4j . For didactical reasons and to strengthen the understanding of this prototype a scenario, applied to route planning in the city of Bern (Switzerland) is shown in the paper.

In this paper we describe a new approach to quantify the stability and coalescence kinetics of thermally switchable emulsions using an imaging-based microcentrifugation method. We first show that combining synchronized high-speed imaging with microfluidic centrifugation allows the direct measurement of the thermodynamic stability of emulsions, as expressed by the critical disjoining pressure. We apply this to a thermoresponsive emulsion, allowing us to measure the critical disjoining pressure as a function of temperature. The same method, combined with quantitative image analysis, also gives access to droplet-scale details of the coalescence process. We illustrate this by measuring temperature-dependent coalescence rates and by analysing the temperature-induced switching between two distinct microscopic mechanisms by which dense emulsions can destabilise to form a homogeneous oil phase.

Purpose – Wafer-level stencil printing of a type-6 Pb-free SAC solder paste was statistically evaluated at 200 and 150 μm pitch using three different stencil manufacturing technologies: laser cutting, DC electroforming and micro-engineered electroforming. This investigation looks at stencil differences in printability, pitch resolution, maximum achievable bump height, print co-planarity, paste release efficiency, and cleaning frequency. The paper aims to discuss these issues. Design/methodology/approach – In this paper, the authors present a statistical evaluation of the impact of stencil technology on type-6 tin-silver-copper paste printing. The authors concentrate on performances at 200 and 150 μm pitch of full array patterns. Key evaluated criteria include achievable reflowed bump heights, deposit co-planarity, paste release efficiency, and frequency of stencil cleaning. Box plots were used to graphically view print performance over a range of aperture sizes for the three stencil types. Findings – Fabrication technologies significantly affect print performance where the micro-engineered electroformed stencil produced the highest bump deposits and the lowest bump height deviation. Second in performance was the conventional electroformed, followed by the laser-cut stencil. Comparisons between the first and fifth consecutive print demonstrated no need for stencil cleaning in the case for the micro-engineered stencil for all but the smallest spacings between apertures. High paste transfer efficiencies, i.e. above 85 per cent, were achieved with the micro-engineered stencil using low aperture area ratios of 0.5. Originality/value – Stencil technology influences the maximum reflowed solder bump heights achievable, and bump co-planarity. To date, no statistical analysis comparing the impact of stencil technology for wafer-level bumping has been carried out for pitches of 200 μm and below. This paper gives new insight into how stencil technology impacts the print performance for fine pitch stencil printing. The volume of data collected for this investigation enabled detailed insight into the limitations of the printing process and as a result for suitable design guidelines to be developed. The finding also shows that the accepted industry guidelines on stencil design developed by the surface mount industry can be broken if the correct stencil technology is selected, thereby increasing the potential application areas of stencil printing.

Objective To identify the signs that can help to differentiate torsion of the appendix testis (AT) and epididymitis and to establish the incidence of the various pathologic entities in boys with an acute scrotum. Materials and Methods A retrospective study was performed of the data from all boys treated at our institute from January 2008 to January 2012 for the diagnosis of an “acute scrotum.” The clinical and, if available, ultrasound findings were documented. Differences between groups were calculated using a chi-square test or analysis of variance and classification and regression tree analysis. Results A total of 241 boys with acute scrotal pain were included and underwent surgical exploration. Of the 241 boys, 163 (70%) had AT, 44 (18.5%) had epididymitis, 31 (13.3%) had testicular torsion, and 3 (1.3%) had idiopathic scrotal edema. The incidence of AT was significantly increased in the colder months (P = .01). We found that AT and epididymitis shared several aspects but differed regarding dysuria (epididymitis, P ≤.001), a painful epididymis on palpation (epididymitis, P = .028), increased epididymal echogenicity (epididymitis, P = .043), augmented peritesticular perfusion (epididymitis, P = .05), and a positive blue dot sign (AT, P

Objective To test the clinical and sonographic predictors of testicular torsion (TT) with the aim of reducing negative exploration rates. Patients and Methods We performed a prospective study of all boys treated for ‘acute scrotum’ at our institute between January 2001 and April 2012 and clinical findings were documented. If available, ultrasonography (US) was added to the diagnostic evaluation. A prediction of the diagnosis was based on clinical and sonographic features, and was followed by surgical exploration in all patients. Results A total of 104 patients were included in the 16-month period of the study. No single finding excluded TT. The clinical features (pain 55%. Ultrasound predictors alone were not able to identify all boys with TT. Conclusions It is safe to refrain from routine surgical exploration in every child with acute scrotum if the clinical score is applied, which results in a marked reduction of negative explorations. A reliable diagnosis could not be obtained based on US alone. As scrotal US is unpleasant for the child, we propose to refrain from this if the clinical score is positive. Patients with a negative clinical score are suitable candidates for US to establish and secure diagnosis.

We report an experimental method to investigate droplet dynamics in centrifuged emulsions and its application to study droplet compression and coalescence. The experimental setup permits in situ monitoring of an ensemble of droplets in a centrifuged monolayer of monodisperse emulsion droplets using optical microscopy. We studied a hexadecane-in-water emulsion stabilized by the ionic surfactant sodium-n-dodecyl sulfate as a model system. With a microfluidic T-junction emulsion droplets of 97 mm diameter are produced which are subsequently inserted into a rectangular glass chamber of 100 mm height. Using an emulsion which is stable against coalescence, we measured the steady-state oil volume fraction in the compressed layer as a function of the compressive force induced by centrifugation, and quantified the deformation of droplets upon compression. To induce coalescence, we decreased the SDS bulk concentration by dilution of the continuous phase with water before the start of centrifugation. The growth rate of the separated oil phase, which forms on top of the emulsion, and the extent of drop–drop coalescence in the droplet layer upon centrifugation were evaluated as a function of the radial acceleration. The potential of the method for studies in emulsion science and possible improvements of the experimental setup are discussed.

Spaced learning has been shown to be effective in various areas like traditional knowledge or motor skill acquisition. To evaluate the impact of implementation of the spaced learning concept in laparoscopic training was the aim of this study. To evaluate the effectiveness of spaced learning, subjects were asked to perform four surgeon’s square knots on a bowel model prior and post 3 h of hands-on training. All subjects were medical students and novice in laparoscopic suturing. Total time, knot stability (evaluated via tensiometer), suture accuracy, knot quality (Muresan score), and laparoscopic performance (Munz checklist) were assessed. Moreover, motivation was accessed using Questionnaire on Current Motivation. Twenty students were included in the study; after simple randomization, ten were trained using “spaced learning” concept and ten conservatively. Both groups had comparable baseline characteristics and improved after training significantly regarding all aspects assessed in this study. Subjects that trained via spaced learning were superior in terms of suture performance, knot quality, and suture strength. Ultimately, spaced learning significantly decreased anxiety and impression of challenge compared to controls. The spaced learning concept is very suitable for complex motor skill acquisition like laparoscopic suturing and knot tying. It significantly improves laparoscopic performance and knot quality as shown by the knot score and suture strength. Thus, we recommend to incorporate spaced learning into training courses and surgical programs.

The Bonga FPSO was designed to process 280 MBLPD gross liquid, constrained by the three-phase low pressure (LP) separator capacity. The projected production forecast indicated that additional future volumes of produced fluids from the Bonga field could exceed the design capacity of the installation. FMC's Inline PhaseSplitter was identified as a solution for debottlenecking the three-phase LP separator liquid handling capacity. The PhaseSplitter is a compact pipe-based cyclonic separator that splits the feed flow into a gas stream with limited liquid carry-over and a liquid stream with limited gas carry-under. The performance objective for the PhaseSplitter is 70 % or more gas removal while keeping liquid carry-over in the gas outlet below 1 % volume fraction. In this paper, we report results of a technical qualification program (TQP) for the PhaseSplitter as a debottlenecking tool for the three-phase LP separator. We used a down-scaled 3 inch pipe of the PhaseSplitter as compared to a 24 inch full-scale field unit. A model fluid whose physical properties resemble the Bonga fluids was used, thereby giving credence to the test results. A test matrix covering a range of representative feed conditions was probed: gas volume fraction (GVF) 75 - 90%, water cuts 20 - 80% and inlet momentums 4500 - 11000 Pa. We measured the percentage of gas removed from the feed and the amount of liquid carry-over into the removed gas as function of the flow split to the gas outlet. The results show that for almost all test conditions, acceptance criteria that were set for the PhaseSplitter were met, i.e. 75 - 80% gas removal and liquid carry-over with the gas less than 1%. Gas-liquid separation performance gradually decreases with decreasing momentum and GVF in the feed. We observed no dependence of separation performance on the feed water cut. We plotted the results as function of the normalized flow split showing universal trends. These trends provide a means to control the separation performance by monitoring the pressure drop over both outlets. We conclude that the PhaseSplitter delivers a robust performance under steady-state conditions over a wide range of operating conditions.

Because of a rapid growth of worldwide energy consumption an economical use of power is a necessity to ensure the supply reliability. One key technology to realize sparing energy use is power electronics. The cost of power electronic devices became an important aspect in this application due to its broader use compared to the past. In recent years, high efficiency at a given lifetime with low system costs are the main focus for the development of power electronic system. To shorten development and qualification time of such systems simulation of electrical and thermal performance is done extensively in order to optimize cost, life time and efficiency of the device. The thermal resistance of the modules and in consequence the thermal resistance of the interconnect materials are important factors of the performance of such systems. The paper discusses different thermal conductivity measurements and die attach materials and substrate materials, along with the measurements with a package like system, containing the die attach material itself as well as interfaces of the die attach material to the die and the substrate. Different measurement methods available to determine the thermal performance in such a system. Some examples are the thermal diffusivity and the junction to case thermal resistance measurement. Measured and simulated values were compared and discussed.

Introduction: The embryogenesis of gastroschisis is not completely understood. The aim of our study was to evaluate the impact of a simple abdominal wall defect versus a defect including eviscerated intestine or omentum for the development of gastroschisis in a fetal lamb model. Material and Methods: At mid-gestation (day 77) an abdominal wall defect was fetoscopically created with three different approaches in 19 German blackhead sheep. The intestine was eviscerated in 7 fetuses (group 1). The peritoneum was incised and a patch of the omentum pulled through the incision in 5 fetuses (group 2). In 7 fetuses (group 3) the skin and rectus muscle were incised until the peritoneum was visible. In this group, no abdominal contents were exteriorized and the peritoneum was left intact. A second fetoscopic procedure was performed 21 days later, assessing the condition and extension of eviscerated bowel. The fetus was retrieved by Cesarean section on day 132 and evaluated. Results: The second fetoscopy acting as a control for the creation of gastroschisis demonstrated eviscerated and inflamed intestine in all 3 groups. The amount of eviscerated intestine did not appear to depend on the size of the defect nor on its duration. Discussion: It appears that a simple incision of the abdominal wall with intact peritoneum is sufficient for the development of gastroschisis in a fetal sheep model. This finding may improve the understanding of the etiology of gastroschisis.

We report the results of a study on emulsion stability in a microfluidic channel flow using an integrated microfluidic device. The microfluidic circuit enables production of a monodisperse oil-in-water emulsion and monitoring of emulsion stability upon shear-induced collisions. Sodium-n-dodecyl sulfate was used as emulsifier, and hexadecane as dispersed phase. We measure the mean drop size at the end of the collision channel as a function of the surfactant and sodium chloride bulk concentration, and as a function of the total flow rate. We find that emulsions are stable against coalescence for SDS bulk concentrations down to 10(-6) M within the residence time of the droplets in the channel in the absence of added NaCl. The stability of the emulsion at these low SDS bulk concentrations is interpreted in terms of a reduced mobility of the droplet interfaces, which slows down drainage of the film of the continuous phase between the droplets. Emulsions stabilized by SDS with added NaCl in the continuous phase display a transition from a stable to unstable regime when increasing the NaCl bulk concentration from 0.1 M to 0.3 M, which is in agreement with predictions using simple DLVO force calculations for colloidal stability. We also estimate the characteristic coalescence time between droplets using a simple coalescence theory and compare the results with values obtained by us previously from trajectory analysis of colliding droplet pairs.

Steroid hormone progesterone has been found to play an important role in the migration of spermatozoa through the reproductive tract, as well as to induce hyperactive motility and increase sperm velocity. The aim of this study was to examine whether progesterone could induce beneficial effects in vitrified and slow-frozen spermatozoa. During the research process, 50 semen samples were divided into three treatment groups; noncryopreserved, slow-freezing and vitrification. After thawing and an incubation period of 2 hr to induce capacitation, semen samples from each treatment group were treated with 50 nM, 25 nM progesterone and a control solution for 30 min. Thereafter, the sperm suspensions were examined manually to assess the proportion of viable and motile spermatozoa, as well as using the CASA to evaluate the velocity parameters. The results indicated a higher proportion of progressively motile spermatozoa in vitrified teratozoospermic samples and improved velocity parameters in slow-frozen normozoospermic and teratozoospermic samples. The main conclusion of this research was that the used progesterone concentration of 50 nM was sufficient to significantly improve the motility of vitrified teratozoospermic samples and velocity parameters of cryopreserved sperm samples. The present findings might have important implications in determining ways of improving the current low rates of motility in cryopreserved spermatozoa.

Molecular beam scattering experiments are used to investigate reactions of SO 2 at the surface of a molten alkali carbonate eutectic at 683 K. We find that two-thirds of the SO 2 molecules that thermalize at the surface of the melt are converted to gaseous CO 2 via the reaction . The CO 2 product is formed from SO 2 in less than 10 -6 s, implying that the reaction takes place in a shallow liquid region less than 100 Å deep. The reaction probability does not vary between 683 and 883 K, further implying a compensation between decreasing SO 2 residence time in the near-interfacial region and increasing reactivity at higher temperatures. These results demonstrate the remarkable efficiency of SO 2 → CO 2 conversion by molten carbonates, which appear to be much more reactive than dry calcium carbonate or wet slurries commonly used for flue gas desulfurization in coal-burning power plants.

The aim of the current study was to investigate the role of promoter methylation of adenomatous polyposis coli (APC) and epithelial cadherin (E-cadherin) genes in endometrial tumorigenesis. The methylation status of both genes was investigated in 43 cases of normal endometrium, 21 simple hyperplasia, 17 atypical hyperplasia, and 86 endometrial carcinoma (EC). Additionally, the methylation pattern of both genes was analyzed in 24 primary ECs and their corresponding metastases. DNA methylation of the APC gene increased from atypical hyperplasia (23.5%) to endometrial carcinoma, reaching its highest level of 77.4% in early stage cancer (FIGO I and II) and decreasing stepwise to 24.2% in advanced stage carcinomas (FIGO III and IV). No methylation of APC was found in normal endometrium or simple hyperplasia. Methylation of E-cadherin was found only in EC (22.1%). The mean age of the patients with aberrant APC methylation was 68.8 years and was significantly higher compared to the mean age (60.9 years) of the patients without methylation of APC promoter (P = 0.02). APC promoter methylation significantly correlated with decreased protein expression of APC (P = 0.039), with increased expression of the Ki-67 proliferative marker (P = 0.006) and decreased metastatic potential (P = 0.002). There was no correlation between APC and E-cadherin methylation patterns and the other clinicopathologic features, nor with patient outcome. Our results suggest that hypermethylation of APC promoter region is an early event in endometrial tumorigenesis.