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The crack initiation life of a ductile additively manufactured nickel-based superalloy is studied and modeled for low-cycle fatigue and thermomechanical fatigue conditions up to 600 degrees C. Isothermal experiments were performed on smooth specimens at temperatures up to 600 degrees C with different applied strain ranges. Additionally, thermomechanical fatigue experiments at 100-450 degrees C and 100-600 degrees C were performed on smooth specimens under in-phase and out-of-phase conditions. A life prediction model accounting for the anisotropy was developed, where the temperature cycle is accounted with a Delta T$$ \Delta T $$-functionality, generating good agreements with the experiments. The model was also validated on notched specimens undergoing thermomechanical fatigue conditions at 100-500 degrees C using simplified notch correction methods. Funding Agencies|Linkoping University; Siemens Energy AB

IntroductionNeuromuscular disorders (NMDs) have a heterogeneous etiology. A genetic diagnosis is key to personalized healthcare and access to targeted treatment for the affected individuals.MethodsIn this study, 861 patients with NMDs were analyzed with genome sequencing and comprehensive variant calling including single nucleotide variants, small insertions/deletions (SNVs/INDELs), and structural variants (SVs) in a panel of 895 NMD genes, as well as short tandem repeat expansions (STRs) at 28 loci. In addition, for unsolved cases with an unspecific clinical presentation, the analysis of a panel with OMIM disease genes was added.ResultsIn the cohort, 27% (232/861) of the patients harbored pathogenic variants, of which STRs and SVs accounted for one-third of the patients (71/232). The variants were found in 107 different NMD genes. Furthermore, 18 pediatric patients harbored pathogenic variants in non-NMD genes.DiscussionOur results highlight that for children with unspecific hypotonia, a genome-wide analysis rather than a disease-based gene panel should be considered as a diagnostic approach. More importantly, our results clearly show that it is crucial to include STR- and SV-analyses in the diagnostics of patients with neuromuscular disorders.

We combine X-ray-specific tracer particles, a photon counting detector, and a liquid metal anode X-ray source to achieve O(1 kHz) X-ray imaging speeds in the laboratory, 15x faster than previous comparable studies. To demonstrate the capabilities of these imaging speeds, we conduct three experiments: 2D and 3D X-ray particle tracking velocimetry (XPTV) of Poiseuille pipe flow, 3D XPTV of flow around a Taylor bubble, and 3D scalar mixing with a laminar jet. These experiments demonstrate the performance improvement of combining the aforementioned elements, the applicability to multiphase flows and deforming systems, and the potential to capture scalar and vector quantities simultaneously. Most importantly, these experiments are conducted in the laboratory, showing that in-lab X-ray particle velocimetry techniques are now usable for a wider range of flows of interest.

Real-time forecasting of travel demand during wildfire evacuations is crucial for emergency managers and transportation planners to make timely and better-informed decisions. However, few studies focus on accurate travel demand forecasting in large-scale emergency evacuations. Therefore, this study develops and tests a new methodological framework for modeling trip generation in wildfire evacuations by using (a) large-scale GPS data generated by mobile devices and (b) state-of-the-art AI technologies. The proposed methodology aims at forecasting evacuation trips and other types of trips. Based on the travel demand inferred from the GPS data, we develop a new deep learning model, i.e., Situational-Aware Multi-Graph Convolutional Recurrent Network (SA-MGCRN), along with a model updating scheme to achieve real-time forecasting of travel demand during wildfire evacuations. The proposed methodological framework is tested in this study for a real-world case study: the 2019 Kincade Fire in Sonoma County, CA. The results show that SA-MGCRN significantly outperforms all the selected state-of-the-art benchmarks in terms of prediction performance. Our finding suggests that the most important model components of SA-MGCRN are evacuation order/warning information, proximity to fire, and population change, which are consistent with behavioral theories and empirical findings.

Supplemental figures

Additional file 1: Supplementary methods, Table S1. List of SNPs used for genotyping, Table S2. In house developed open source software used, Table S3. Publicly available open source software used, Table S4. Publicly available databases used, Table S5. Cases with a dual diagnosis. Figure S1. Steps performed in the MIP rare disease pipeline, Figure S2. Turnaround time per quarter, Figure S3. Statistics regarding number genes and patients.

Additional file 4: Supplementary Fig. S1. Schematics of the workflow for variant filtration.

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Additional file 4.

Additional file 1 Supplementary material. This file includes the supplementary material. File is in pdf format.

Additional file 5.

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Additional file 2.

The purpose of this study was to explore, by qualitative methods, the meaning of equine-assisted social work (EASW) both to young women with self-harm problems and their staff in residential treatment. Data were collected by in-depth interviews with eight staff members and nine clients. Human-horse interaction was observed subsequently in three of the staff and four of the clients. Based on the narratives of the staff members and the clients, who agreed, the horse’s ability to read human emotions made the staff and clients aware of their own emotions. In order not to alienate the horse or make the situation dangerous, which intensified their sense of being in the present, both the clients and staff had to regulate their emotions. As a result the resistance for change decreased, made the participants more likely to regulate their emotions and change behavior rather than avoid the situation or the information. The horse seemed to set the framework for the interaction between the staff and young women. The fact that even the staff could fail in the interaction with the horse, affected the interaction between staff and clients making it more informal and dynamic. A relationship based on empathy, trust, respect and negotiation, where clients shared private matters, resulted in the perception of a more authentic relationship. Further research is needed to see which conditions are favourable for achieving an authentic relationship and which conditions possibly fail.

Utbyggnaden av förnybar el från vindkraft och solceller sker nu mycket snabbt. En nackdel med dessa energikällor är att produktionen i princip inte är kontrollerbar, utan den beror av rådande väderlek och inte av det aktuella behovet. Eftersom el måste tillföras i samma ögonblick som den konsumeras, behöver det därför finnas tillgång på elkraft för att balansera tillförseln och konsumtionen. I Sverige har vattenkraften en nyckelroll som reglerkraftkälla. Ett annat möjligt alternativ för balansering av elbehovet är produktion av el från biobränslen, som inte bara är förnybara och koldioxid-neutrala, utan också är lagringsbara. Syftet med denna studie var därför att undersöka vilka möjligheter det finns att producera biobaserad el för balansering av elbehovet i ett framtida elsystem med hög andel vind- och solkraft. Arbetet baserades på litteraturstudier. För att kunna bidra med balanskraft krävs snabbhet, hög tillgänglighet och uthållighet. Användning av gasformiga biobränslen (i t.ex. gasmotorer eller gasturbiner) ger normalt hög reaktionssnabbhet, medan tillgängligheten bl.a. beror av den använda tekniken. Ur teknisk synpunkt bör det inte finnas några större hinder för att el från gasformiga biobränslen ska uppfylla dessa två förstnämnda villkor. Vid användning av fasta och flytande biobränslen i kraftvärmeverk är värmebehovet en avgörande faktor för tillgängligheten. Uthålligheten beror till stor del på vilka lagringsmöjligheter som finns. Fasta biobränslen har en stor fördel genom att de kan lagras i stora volymer till låga kostnader. Kostnaderna för lagring av gasformiga bränslen är däremot höga. Med dagens teknik och kostnadsläge, är det därför svårt för ett och samma biobränsle att kombinera snabbhet och hög tillgänglighet med uthållighet. Generellt är kostnaderna idag betydligt högre för biokraft än t.ex. för vattenkraft. I jämförelse med avtalad förbrukningsreduktion, dvs. att förbrukare mot betalning minskar sin konsumtion vid effekttoppar, så kommer biobaserad balanskraft också att få svårt att hävda sig. I de flesta fall är biokraft idag snarare en biprodukt (om än en viktig sådan) i anläggningar som främst är avsedda för produktion av värme och processånga. Ur resurssynpunkt är det självklart positivt att man får ut flera nyttigheter ur samma råvara, och för elproduktionen är det också nöd-vändigt av lönsamhetsskäl. En annan kostnadsaspekt gäller anläggningarnas underhåll vid en mer intermittent drift. Ju fler starter och stoppar, och ju mer ojämnt en anläggning går, desto högre blir underhållskostnaderna. Om produktionen i ett stort antal mindre anläggningar koordineras, och därmed fungerar som en enhet, dvs. som ett virtuellt kraftverk, kan de delta som en aktör på elmarknaden och där-med öka vinstmöjligheterna. Med en större flexibilitet i produktionen kan man i högre grad följa elens prisförändringar, vilket innebär att man kan sälja mer el när priserna är höga, d.v.s. när efterfrågan är hög i förhållande till utbudet. Detta ökar inte bara möjligheterna för produ-centerna att förbättra sin lönsamhet, utan en viktig bieffekt blir också att man kapar effekt-topparna. Detta förutsätter dock bl.a. att priserna varierar i tillräckligt hög grad så att even-tuella vinster kan täcka de ökade kostnader detta innebär, t.ex. när det gäller lagring av bräns-lena och ett ökat slitage. Större variationer i elpriset kan dock förväntas i framtiden när an-delen intermittent el från sol och vind ökar. När det gäller forskningsinsatser, så bör man fokusera på ökad flexibilitet i produktionen av biokraft. Det är också viktigt att man har en helhetssyn för biobränslena och inte bara foku-serar på integrationen av biokraft i ett framtida smart elsystem baserat på t.ex. vind-, sol-, våg- och vattenkraft, ellagring, elfordon och prisanpassad förbrukning. För biobränslen krävs en mer vidgad syn på smarta och flexibla distributionssystem som också inkluderar produktion av värme och andra utvunna nyttigheter från råvaran.

Handeln av grotflis, flis från grenar och toppar vid slutavverkning, har ökat kraftigt under de senaste åren. Inmätningen sker vanligtvis vid mottagningsplatsen och betalningen sker vanligen utifrån energiinnehåll med uppgift om fukthalt. Syftet med denna studie har varit att jämföra olika mätmetoder för grotflis som bygger på volym, vikt och olika sätt att uppskatta fukthalten. Den metod som antas som facit bygger på 10 prover per container vilket innebär 30 prover per leverans. Detta ”facit” har jämförts med sex alternativa sätt att beräkna lassens energivärde. En av metoderna är den som tillämpas av VMF Syd och en annan är en metod som bygger på en finsk modell att uppskatta fukthalten. Studien är avgränsad till 44 leveranser grotflis, i huvudask från barrträd, under vinter och sommarförhållanden och transporten har skett i ekipage om tre fliscontainrar. Medelfukthalten för de vinterkörda leveranserna bestämdes via 10 prov per container, LNU/SLU, till 39,3 % medan VMF Syd uppmätte en medelfukthalt på 38,7 %, via den finska metoden uppskattades fukthalten för de vinterkörda leveranserna till 45,5 %. Medelfukthalten för de sommarkörda leveranserna bestämdes av LNU/SLU till 27,9 %, av VMF Syd till 27,0 % meden uppskattningen via den finska metoden gav en medelfukthalt på 30 %. De vinterkörda ekipagen hade enligt det antagna facit, LNU/SLU, ett energiinnehåll i medeltal på 104,2 MWh medan energiinnehållet enligt fukthalten från VMF blev energiinnehållet i medeltal 105,7 MWh och då fukthalten bestämdes med den finska metoden blev energiinnehållet i medeltal 90,8 MWh. För de sommarkörda leveranserna blev energiinnehållet i medeltal 110,8 MWh enligt LNU/SLU, 112,5 MWh enligt VMF Syd och 105,7 MWh enligt den finska metoden. När det gäller de olika mätmetoderna visade det sig att M6, energivärde direkt ifrån mätsedel, var den bästa med en kvotspridning på 6,4 % i jämförelse med antaget facitvärde beräknat enligt LNU/SLU. Anledningen till detta är att denna mätning baseras på av fukthalten och beräknat effektivt värmevärde för varje enskild leverans medan de andra bygger på ett beräknat ”erfarenhetstal” för energiinnehåll per ton respektive per m3s för leveranserna i studien. Om mätningen istället baseras på erfarenhetstal istället för fukthaltsmätning visar resultaten att volymmätning ger en mindre kvotspridning, runt 10 %, jämfört med viktbaserad mätning där kvotspridningen hamnar på ca 17 % jämfört med facit. Fukthaltsmätning enligt den finska metoden ger en kvotspridning på ca 15 %. Volymminskningen under transport för alla leveranser i studien uppmättes i medeltal till strax över 2 % och resultaten visar också att den största volymminskningen, ca 70 %, sker redan under de första kilometrarna. Skillnaden mellan VMFs volymmätning och den mer noggranna volymmätningen utförda av LNU/SLU visade sig vara endast 0,5 %. Men då lassen krattats för att möjliggöra denna mätning har även VMFs inmätning förenklats.

The objectives of this project were a) to investigate and model the equilibrium moisture content of straw from cereals and oilseed crops, b) to investigate and quantify possible differences in straw equilibrium moisture content between different crops, varieties and threshing methods (shaker and axial flow combines), c) to investigate the moisture absorption rates in straw from different crops and threshing methods, d) to investigate the hysteresis characteristics of straw, i.e. the difference in moisture content between absorption and desorption conditions, e) to develop a model to simulate the moisture content in straw swathes on an hourly basis, and f) to estimate model parameters by monitoring the moisture content in straw swathes in field trials and to evaluate the general validity of the model. The equilibrium moisture content was investigated in climate chambers by keeping the isotherms +5°C, +15°C and +25°C constant while the relative humidity was increased stepwise from 35% to 53%, 72% and finally 90%. The samples comprised straw from winter wheat, spring wheat, triticale, rye, barley, oats, winter rape and spring rape. For winter wheat, there were samples from two varieties and from unthreshed, 'yellow' and 'grey' straw. For spring wheat, there were samples from two varieties and straw from shaker and axial flow combines. The results showed, for example, that a moisture content of 18% (wet basis) was reached at a relative humidity of 85-90% for winter wheat (see below). Five commonly used equations for modelling the equilibrium moisture contents (the Henderson, Chung-Pfost, Halsey, Oswin and GAB-equations) were adapted to the experimental data by non-linear regression. The Halsey equation (the version independent of temperature) had the best goodness of fit for most straw types investigated. In a comparison of straw from different crops, no statistically significant differences in the equilibrium moisture content were found, except for oat straw. This type of straw had somewhat higher equilibrium moisture content, especially at high relative humidity. At low relative humidity, straw from rape had a somewhat higher equilibrium moisture content, but this difference was not statistically significant. Furthermore, no statistically significant differences were found between 'yellow' and 'grey' straw, or between straw from shaker and axial flow combines. The moisture absorption rate was investigated at a temperature of +15°C when the relative humidity was increased from 53% to 72%. The results showed that oats had the highest rate initially, while straw from spring wheat had the lowest. However, all samples reached their equilibrium moisture content within about 10 hours. The climate chamber investigations also showed that straw has some absorption-desorption hysteresis. In these trials, the temperature was kept at +15°C, while the relative humidity was varied according to 53% → 72% → 90% → 72% → 53%. The hysteresis was estimated to be 1-2 percentage points. A computer model, which has earlier been applied to flax straw, was used to simulate the moisture content in straw swathes under field conditions. The model took into account factors such as evaporation of water and formation of dew. It used precipitation, global radiation, temperature, relative humidity, wind speed and cloudiness as input data to calculate the straw moisture content on an hourly basis. Three field trials were carried out during 2007-08, when the moisture content was monitored in swathes with winter wheat straw. The model parameters were then determined by regression. Comparisons between measured and predicted moisture contents showed that the model simulated the drying and rewetting processes with acceptable accuracy.

Use of processed biofuels (pellets, briquettes) has greatly increased in Sweden in recent decades, mainly to replace fossil fuels in large boilers, e.g. in coal powder boilers. More recently, the demand from private households and residential heating systems has also increased, mainly due to conversion from fossil heating oil. This increased interest in pellets and briquettes for heating is beginning to cause a shortage of the traditional raw materials, sawdust and wood shavings, and therefore attention is turning to using a variety of agricultural products as raw material. Such raw materials include cultivated energy crops and wastes and by-products from agriculture. This study describes the typical systems currently used for production of pellets and briquettes and investigates the possibility of using energy crops (Salix, reed canary-grass and hemp) and various wastes and by-products from processing of farm products (straw, cereal screenings, rape-seed meal and distiller’s waste) as raw materials. Previous experiences of pelleting and briquetting of these raw materials are reviewed in order to comprehensively identify possible combustion problems that may occur. On the basis of the results obtained, scenarios for possible production systems in a five-year perspective are presented and the costs and energy demands for these systems calculated. These future scenarios include largescale plants and micro-scale plants, as well as static and mobile equipment. The five main conclusions from the study are: - The farm raw materials of greatest interest for large-scale production are pelleted Salix and reed canary-grass. They have competitive prices and acceptable fuel properties and could be mixed with sawdust in existing large-scale pelleting factories in Sweden. - Straw has low production costs but can cause serious ash-related problems. Hemp has too high production costs to be of commercial interest, while distiller’s waste and rape-seed meal currently have a higher alternative value when used as protein feed. Cereal screenings can be a suitable raw material provided that they only make up a minor proportion in mixtures with other more problem-free raw materials. - The scale of production has a great influence on production costs. In large-scale plants, the machinery and equipment, etc. are used much more efficiently than in smaller plants, which results in lower costs. - Small-scale pelleting, both static and mobile, requires cheap raw materials and a high through-put to be profitable. In most cases, briquetting would be more commercially viable. - The energy consumption in manufacturing pellets from dry farm by-products is generally no higher than when moist sawdust is used as the raw material. More energy is admittedly required for cultivation and transport of farm by-products, but since there is no need for drying the total energy consumption is often lower. However, wet raw materials such as fresh Salix and distiller’s waste can increase the total energy consumption.

The increased awareness of sustainable production in our society in recent decades has led to the search for new environmentally-friendly products. Natural fibres from flax (Linum usitatissimum L.), which are renewable and can be degraded biologically after their use, are an alternative that has been considered as a replacement for synthetic fibres in many industrial applications, for example, as reinforcement in composites, rubber and concrete. The objective of` this work was to carry out a thorough literature review on the production and use of flax for non-textile applications in general, and on aspects related to harvest and handling in particular. The report starts with a review of earlier Swedish research and development projects and then focuses on harvest and handling methods. Thereafter, quality aspects related to harvest and handling of flax, i.e. straw moisture contents and degree of retting, are reviewed. A summarising discussion and proposals for future research are presented in the last chapter. After the closure of the last flax long fibre processing plant in 1966, there has been no commercial production of flax fibres in Sweden. However, interest in using flax fibres in non-textile applications was stimulated in the late 1980s, and a number of projects started in the 1990s with the aim of restoring Swedish flax fibre production. Today, there are no flax processing plants in operation, but it is recommended that new research and development projects be directed towards the creation of a demand for biofibres before such plants are established. This would be a first step towards creating a future market for short natural fibres obtained from flax, and also from other fibre crops such as hemp. The harvest and handling operations constitute an important part of the total production costs, Computer simulation of these operations is recommended in order to find more cost-effective and reliable delivery systems, Such simulations should include quality aspects regarding the straw moisture content and the degree of retting, provided that reliable, quick and inexpensive methods to assess the degree of retting are developed, and that models describing the moisture content changes and the progress of retting are constructed.

Straw is a renewable biomass that has a considerable potential to be used as fuel in rural districts. This bulky fuel is, however, produced over large areas and must be collected during a limited amount of days and taken to the storages before being ultimately transported to heating plants. Thus, a well thought-out and cost-effective harvesting and handling system is necessary to provide a satisfactory fuel at competitive costs. Moreover, high-quality non-renewable fuels are used in these operations. To be sustainable, the energy content of these fuels should not exceed the energy extracted from the straw. The objective of this study is to analyze straw as fuel in district heating plants with respect to environmental and energy aspects, and to improve the performance and reduce the costs of straw handling. Energy, exergy and emergy analyses were used to assess straw as fuel from an energy point of view. The energy analysis showed that the energy balance is 12:1 when direct and indirect energy requirements are considered. The exergy analysis demonstrated that the conversion step is ineffective, whereas the emergy analysis indicated that large amounts of energy have been used in the past to form the straw fuel (the net emergy yield ratio is 1.1). A dynamic simulation model, called SHAM (Straw HAndling Model), has also been developed to investigate handling of straw from the fields to the plant. The primary aim is to analyze the performance of various machinery chains and management strategies in order to reduce the handling costs and energy needs. The model, which is based on discrete event simulation, takes both weather and geographical conditions into account. The model has been applied to three regions in Sweden (Svalöv, Vara and Enköping) in order to investigate the prerequisites for straw harvest at these locations. The simulations showed that straw has the best chances to become a competitive fuel in south Sweden. It was also demonstrated that costs can be reduced by adopting appropriate management strategies. Moreover, SHAM has also been used to determine the number of machines that result in the lowest total fuel costs. It was shown that straw can be delivered to a plant at Svalöv at a cost of 29.6 SEK GJ-1. Two new technologies were evaluated by using SHAM: systems based on compact rolls and systems based on chopped straw stored outdoors. The costs were about 5-20% higher with these methods compared with systems based on high-density balers, but their prospects of becoming competitive alternatives in the future are good.

Two storage methods for chipped willows (Salix spp.), cold air ventilation and sealed storage, were tested at laboratory scale. Fresh chips were stored in six insulated containers for 62 days in a store-room. Temperature development during storage was continuously monitored. Dry matter losses and fungal spore counts, in the central part of the containers, were determined. Two 1.7 m3 containers were continuously ventilated with ambient air (mean temperature 2.7° C) at a rate of 175 m3∙h^-1∙t^-1 dry matter. As a control, a third unventilated identical container was used. To test sealed storage, a similar experiment was conducted using two containers of 0.63 m3. A third, unsealed, container served as a control. These three containers were placed in a room where the average temperature during storage was 14.7° C. In the central part of the ventilated containers, the average temperature of the chips was close to ambient temperature (average 4° C) during most of the storage period while the temperature in the unventilated container averaged at 32.4° C and a maximum of 42° C. The dry matter losses were 5.2% and 13.3% by weight in the ventilated and the control containers respectively. The total number of micro fungal spores increased by 3-5 times in the chips stored in the ventilated containers but, in the control, it increased more than 100 times. The temperature in the central part of the sealed containers was close to ambient (14° C), while the maximum temperature of the control was 59.3° C with an average of 28.8° C. Different dry matter losses were measured in the two sealed containers, 2.7% and 6.0%. However, higher loss of dry matter (8.2%) was determined in the control. The fungal growth in the test containers was less intensive than that in the control. The total number of spores was increased by 3-4 folds in the sealed material compared to 60 times in the control.

This report is primarily intended to support courses for undergraduates in agricultural engineering, but is also intended for a wider use among advisers in agriculture and forestry, farmers, house owners etc. The report consists of two sections. The first part considers energy management, energy conservation and estimation of energy and power requirements of buildings. In addition, combustion, furnaces and heat distribution are considered. The second part deals with production and utilization of biofuels, for instance wood, forest residues, salix, straw, energy grass, cereals, biogas and peat. Finally, economic and market aspects are discussed.

The purpose of this essay is to review straw conservation systems, from the swath until the straw has been unloaded at the heating plant. Various straw harvesting systems are studied. The harvesting methods are described, as well as the capacities and the resulting material properties. In addition, a number of storage methods are investigated. Procedures of making, conveying and storing briquettes, pellets and powder are investigated. The direct and indirect energy requirements for different harvesting chains are evaluated. The estimates show, with regard to the energy requirements, that straw utilization is very profitable. Cost calculations have been estimated. The figures suggest that a cost of about 0.35 SEK should be attainable for getting the straw delivered to the heating unit.

Contains fulltext : 136372.pdf (Publisher’s version ) (Closed access) Neu-Laxova syndrome (NLS) is a rare autosomal-recessive disorder characterized by a recognizable pattern of severe malformations leading to prenatal or early postnatal lethality. Homozygous mutations in PHGDH, a gene involved in the first and limiting step in L-serine biosynthesis, were recently identified as the cause of the disease in three families. By studying a cohort of 12 unrelated families affected by NLS, we provide evidence that NLS is genetically heterogeneous and can be caused by mutations in all three genes encoding enzymes of the L-serine biosynthesis pathway. Consistent with recently reported findings, we could identify PHGDH missense mutations in three unrelated families of our cohort. Furthermore, we mapped an overlapping homozygous chromosome 9 region containing PSAT1 in four consanguineous families. This gene encodes phosphoserine aminotransferase, the enzyme for the second step in L-serine biosynthesis. We identified six families with three different missense and frameshift PSAT1 mutations fully segregating with the disease. In another family, we discovered a homozygous frameshift mutation in PSPH, the gene encoding phosphoserine phosphatase, which catalyzes the last step of L-serine biosynthesis. Interestingly, all three identified genes have been previously implicated in serine-deficiency disorders, characterized by variable neurological manifestations. Our findings expand our understanding of NLS as a disorder of the L-serine biosynthesis pathway and suggest that NLS represents the severe end of serine-deficiency disorders, demonstrating that certain complex syndromes characterized by early lethality could indeed be the extreme end of the phenotypic spectrum of already known disorders.