Scale-dependent topographic complexity underpins abundance and spatial distribution of ecosystem engineers on natural and artificial structures.

In response to ongoing coastal urbanization, it is critical to develop effective methods to improve the biodiversity and ecological sustainability of artificial shorelines. Enhancing the topographic complexity of coastal infrastructure through the mimicry of natural substrata may facilitate the establishment of ecosystem engineering species and associated biogenic habitat formation. However, interactions between ecosystem engineers and their substratum are likely determined by organismal size and resource needs, thus making responses to topography highly scale-dependent. Here, we assessed the topographic properties (rugosity, surface area, micro-surface orientations) that underpin the abundance and distribution of two ecosystem engineers (fucoids, limpets) across six spatial scales (1-500 mm). Furthermore, we assessed the 'biogenic' rugosity created by barnacle matrices across fine scales (1-20 mm). Field surveys and 3D scanning, conducted across natural and artificial substrata, showed major effects of rugosity and associated topographic variables on ecosystem engineer assemblages and spatial occupancy, while additional abiotic environmental factors (compass direction, wave exposure) and biotic associations only had weak influences. Natural substrata exhibited ≤67 % higher rugosity than artificial ones. Fucoid-covered patches were predominantly associated with high-rugosity substrata and horizontal micro-surfaces, while homescars of limpets (≥15 mm shell length) predominated on smoother substratum patches. Barnacle-driven rugosity homogenized substrata at scales ≤10 mm. Our findings suggest that scale-dependent rugosity is a key driver of fucoid habitat formation and limpet habitat use, with wider eco-engineering applications for mimicking ecologically impactful topography on coastal infrastructure.

Topography-based modulation of environmental factors as a mechanism for intertidal microhabitat formation: A basis for marine ecological design.

Topographic complexity is often considered to be closely associated with habitat complexity and niche diversity; however, complex topography per se does not imply habitat suitability. Rather, ecologically suitable habitats may emerge if topographic features interact with environmental factors and thereby alter their surrounding microenvironment to the benefit of local organisms (e.g., resource provisioning, stress mitigation). Topography may thus act as a key modulator of abiotic stressors and biotic pressures, particularly in environmentally challenging intertidal systems. Here, we review how topography can alter microhabitat conditions with respect to four resources required by intertidal organisms: a source of energy (light, suspended food particles, prey, detritus), water (hydration, buffering of light, temperature and hydrodynamics), shelter (temperature, wave exposure, predation), and habitat space (substratum area, propagule settlement, movement). We synthesize mechanisms and quantitative findings of how environmental factors can be altered through topography and suggest an organism-centered 'form-follows-ecological-function' approach to designing multifunctional marine infrastructure.

Effects of artificial light at night on the feeding behaviour of three marine benthic grazers from the Adriatic Sea are species-specific and mostly short-lived.

Artificial light at night (ALAN) has the potential to change the day-night activity of marine benthic grazers, and can therefore alter the top-down control they exert on macroalgal communities. In laboratory experiments, we investigated the influence of three realistic ALAN regimes on food consumption and feeding rhythmicity in the sea urchins Arbacia lixula and Paracentrotus lividus as well as in the snail Cerithium spp. from the Adriatic Sea. Food consumption was assessed in assays with algal pellets, while feeding rhythms were documented with 24 h time-lapse photography. Both was done in ALAN-acclimated and in non-acclimated animals. We observed temporary and potential long-term changes in the feeding rhythms of Cerithium spp. and Paracentrotus lividus, respectively, but found no lasting influence of ALAN on consumption rates. Effects were weaker when ALAN was applied only part-night, which suggests a possible mitigation measure to reduce the impact of nighttime lighting on coastal ecosystems.

Author Correction: A semi-automated virtual workflow solution for the design and production of intraoral molding plates using additive manufacturing: the first clinical results of a pilot-study.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

RapidNAM: Algorithm for the Semi-Automated Generation of Nasoalveolar Molding Device Designs for the Presurgical Treatment of Bilateral Cleft Lip and Palate.

OBJECTIVE: Nasoalveolar molding (NAM) is an accepted presurgical treatment modality for newborns with cleft lip and palate (CLP). However, the therapy is time-consuming and requires high expertise. To facilitate the treatment, we reveal an algorithm for the automated generation of patient individual NAM devices for neonates with bilateral cleft lip and palate (BCLP) and present results of software validation. METHODS: The algorithm was implemented utilizing Python 2.7 and Blender 2.78a based on 17 digitized (3D-scanning) impressions of maxillae with BCLP. The algorithm segments alveolar structures, bridges clefts, and generates a series of NAM device designs, destined for 3D-printing for subsequent treatment. The datasets were used for first software tests. For validation, a follow-up study was carried out using six new, independent maxilla models. The generated NAM plate designs were examined regarding their potential clinical usability. Furthermore, a deviation analysis was carried out, which measured the plate models' and upper jaw models' surface deviations. RESULTS: Series of NAM devices were generated automatically in 21 out of 23 cases. We calculated an average surface deviation of 0.140 mm (SD: 0.016 mm). Four out of six plate series (follow-up trials) were assessed as probably usable with minor adjustments. CONCLUSION: The algorithm generates 3D-printable series of NAM device designs reliably. We expect most of the series to be clinically usable and that the first plates of each series will fit the patients' maxillae. SIGNIFICANCE: The proposed algorithm has the potential to reduce the therapist's manual work and therefore time effort/costs related to NAM.

Prenatal intrauterine maxillary development - An evaluation with three-dimensional ultrasound.

OBJECTIVES: The aim of this prospective study was to investigate normal fetal maxillary development with volume ultrasound during the prenatal phase, for a better estimation of maxillary growth processes. METHODS: Some 210 3D volumes were obtained in two measurement series from 38 healthy women (gestational age: 19+2 to 31+4 weeks) using a GE Voluson™ E10 ultrasound system. Maxillary length and width were determined in the axial and sagittal planes. Clearly defined, reproducible landmarks were used for measurements. The results were correlated with gestational age and compared with previously reported studies. RESULTS: Total maxillary length ranged from 10.30 to 24.75 mm, total maxillary width from 13.65 to 37.30 mm in an observation period during the second trimester, with high reproducibility for all landmarks. All evaluation results showed steep growth with exponential character. Length growth was determined to be more dominant than width growth. Intra-rater correlation was evaluated to be almost perfect (ICC (3) > 0.8). CONCLUSION: This study presents measurements of physiological fetal maxillary development. The defined landmarks proved to be representative for further investigations. This study serves as a baseline for a better understanding of fetal maxillary growth processes, and may be useful for standardising detection of malformations or intrauterine growth restrictions.

The absolute and relative effects of presurgical nasoalveolar moulding in bilateral cleft lip and palate patients compared with nasal growth in healthy newborns.

BACKGROUND: This study investigated the efficiency of nasoalveolar moulding (NAM) in patients presenting with bilateral cleft lip and palate (BCLP). It focused explicitly on nasal outcome and therefore made comparisons with healthy age-matched infants with normal nasal development. METHODS: Nasal impressions from 19 BCLP patients were analysed at the beginning and at the end of NAM treatment. In addition, nasal impressions from 32 healthy newborns were taken monthly for 4 months. The casts were digitalized and analysed, using defined anatomic landmarks, by two independent observers. Initial values were compared with outcome parameters at the end of NAM therapy and with the healthy cohort. RESULTS: NAM significantly elongated the columella in BCLP patients, with an increase of 106.5% versus 14.5% in healthy newborns. Nostril height showed significant expansion from 4.2 mm to 5.6 mm on the right side, and from 4.3 mm to 6.2 mm on the left side. CONCLUSION: NAM significantly elongated columella length and increased nostril height. The comparison with healthy newborns showed the effectiveness of early cartilage moulding. Detailed knowledge about absolute and relative early nasal growth was gained. However, despite highly effective NAM treatment in BCLP, nasal dimensions will not reach healthy proportions.

Stress Distribution Patterns within Viscero- and Neurocranium during Nasoalveolar Molding: a Finite Element Analysis.

BACKGROUND: The purpose of this study was to evaluate the stress distribution patterns within the viscero- and neurocranium of neonates during nasoalveolar molding. METHODS: Finite element models of 3 different healthy neonates at different times of life (date of birth, 4 weeks, and 3.5 months) were generated on the basis of computed tomography scans. A validated workflow, including segmentation, meshing, setting of boundary conditions, and implementation of a bone density-dependent material model, was carried out for each model. A small and a large unilateral alveolar and hard palatal cleft were virtually cut in each model. The stress distribution pattern in each model was then analyzed by using Ansys APDL. RESULTS: Convergence analysis validated the results. The virtual experiments at the date of birth showed a stress pattern above a previously defined threshold value of 30,000 Pa in the ipsilateral naso-orbital-complex, frontal sinus, and the anterior fossa of the base of the skull, with von Mises values > 35,000 Pa. Stress patterns at the age of 4 weeks and 3.5 months showed reduced von Mises values at < 15,000 Pa. CONCLUSIONS: Nasoalveolar molding therapy is a safe presurgical treatment modality without significant influence on the viscero- and neurocranium of neonates. Treatment, considering the stress distribution at the naso-orbital-complex and anterior fossa of the base of the skull, should begin in the second week of life, and treatment initiation of preterm infants should be adapted respectively.

Facilitating CAD/CAM nasoalveolar molding therapy with a novel click-in system for nasal stents ensuring a quick and user-friendly chairside nasal stent exchange.

Nasoalveolar molding (NAM) aims to improve nasal symmetry with a nasal stent in cleft lip and palate (CLP) patients. When plates have to be exchanged because of dentoalveolar growth or cleft reduction, the nasal stent has to be mounted onto a new plate. This procedure elongates visiting hours for patients and parents or requires second treatment sessions. This study introduces a quick-lock additive manufacturing solution for chairside nasal stent exchange called RapidNAM. A novel taping retention pin has been designed that enables nasal stent insertion. Patients with unilateral CLP were included in this study. Plaster models were digitalized and measured by two independent observers. Two methods of CAD/CAM-molding therapies were compared: (i) conventional adhesion of a nasal stent (CAD/CAM NAM); (ii) quick-lock system in which the nasal stent was transferred to another plate (RapidNAM). CAD/CAM NAM and its refinement RapidNAM significantly increased the cleft-side nasal height and tilted the nose towards symmetry. The quick-lock system minimizes wire adaptations, since the pre-existing stent can be reused. The new nasal stent development seems a feasible solution to minimize visiting hours but with clinically satisfactory results. This new nasal stent system combines traditional elements of NAM with CAD/CAM-technology.

A semi-automated virtual workflow solution for the design and production of intraoral molding plates using additive manufacturing: the first clinical results of a pilot-study.

Computer-aided design and computer-aided manufacturing (CAD/CAM) technology has been implemented in the treatment of cleft lip and palates (CLP) by several research groups. This pilot study presents a technique that combines intraoral molding with a semi-automated plate generation and 3D-printing. The clinical results of two intraoral molding approaches are compared. This is the first clinical investigation of semi-automated intraoral molding. Our study included newborns with unilateral CLP. Plaster models were digitalized and measured by two independent observers. Two methods of CAD/CAM-assisted intraoral molding were compared: (i) stepwise manual design of molding plates (conventional CAD/CAM-intraoral molding) and (ii) a semi-automated approach with an automated detection of alveolar ridges (called RapidNAM) assisted by a graphical user interface (GUI). Both approaches significantly narrowed the clefts and resulted in a harmonic alveolar crest alignment. The GUI was easy to use and generated intraoral molding devices within minutes. The presented design solution is an efficient technical refinement with good clinical results. The semi-automated plate generation with a feasible GUI is fast but allows individual adaptations. This promising technique might facilitate and foster the more widespread use of CAD/CAM-technology in intraoral molding therapy.

The onset of star formation 250 million years after the Big Bang.

A fundamental quest of modern astronomy is to locate the earliest galaxies and study how they influenced the intergalactic medium a few hundred million years after the Big Bang1-3. The abundance of star-forming galaxies is known to decline4,5 from redshifts of about 6 to 10, but a key question is the extent of star formation at even earlier times, corresponding to the period when the first galaxies might have emerged. Here we report spectroscopic observations of MACS1149-JD1 6 , a gravitationally lensed galaxy observed when the Universe was less than four per cent of its present age. We detect an emission line of doubly ionized oxygen at a redshift of 9.1096 ± 0.0006, with an uncertainty of one standard deviation. This precisely determined redshift indicates that the red rest-frame optical colour arises from a dominant stellar component that formed about 250 million years after the Big Bang, corresponding to a redshift of about 15. Our results indicate that it may be possible to detect such early episodes of star formation in similar galaxies with future telescopes.

A density cusp of quiescent X-ray binaries in the central parsec of the Galaxy.

The existence of a 'density cusp'-a localized increase in number-of stellar-mass black holes near a supermassive black hole is a fundamental prediction of galactic stellar dynamics. The best place to detect such a cusp is in the Galactic Centre, where the nearest supermassive black hole, Sagittarius A*, resides. As many as 20,000 black holes are predicted to settle into the central parsec of the Galaxy as a result of dynamical friction; however, so far no density cusp of black holes has been detected. Low-mass X-ray binary systems that contain a stellar-mass black hole are natural tracers of isolated black holes. Here we report observations of a dozen quiescent X-ray binaries in a density cusp within one parsec of Sagittarius A*. The lower-energy emission spectra that we observed in these binaries is distinct from the higher-energy spectra associated with the population of accreting white dwarfs that dominates the central eight parsecs of the Galaxy. The properties of these X-ray binaries, in particular their spatial distribution and luminosity function, suggest the existence of hundreds of binary systems in the central parsec of the Galaxy and many more isolated black holes. We cannot rule out a contribution to the observed emission from a population (of up to about one-half the number of X-ray binaries) of rotationally powered, millisecond pulsars. The spatial distribution of the binary systems is a relic of their formation history, either in the stellar disk around Sagittarius A* (ref. 7) or through in-fall from globular clusters, and constrains the number density of sources in the modelling of gravitational waves from massive stellar remnants, such as neutron stars and black holes.

Establishment of a finite element model of a neonate's skull to evaluate the stress pattern distribution resulting during nasoalveolar molding therapy of cleft lip and palate patients.

Nasoalveolar Molding (NAM) is associated with ambivalent acceptance regarding effectiveness and unknown long-term results. Our purpose was to analyze the stress distribution patterns within the viscero- and neurocranium of neonates during the first phase of NAM therapy. A finite element (FE) model of a healthy four-week-old neonate was generated, derived from a computed tomography scan allowing the implementation of a bone-density-dependent material model. The influence of dental germs with variable material properties, the cleft width and area of expected force application were analyzed in a worst-case scenario. The resulting stress distribution patterns for each situation were analyzed using the software Ansys APDL. The established FE model was verified with a convergence analysis. Overall, stress patterns at the age of four weeks showed von Mises stress values below 60.000 Pa in the viscero- and neurocranium. The influences of the allocation of material properties for the dental germs, the area of force application, and the cleft width were negligible. A workflow to simulate the stress distribution and deformation in neonates attributable to various areas of force application has been established. Further analyses of the skulls of younger and older neonates are needed to describe the stress distribution patterns during NAM therapy.

The close environments of accreting massive black holes are shaped by radiative feedback.

The majority of the accreting supermassive black holes in the Universe are obscured by large columns of gas and dust. The location and evolution of this obscuring material have been the subject of intense research in the past decades, and are still debated. A decrease in the covering factor of the circumnuclear material with increasing accretion rates has been found by studies across the electromagnetic spectrum. The origin of this trend may be driven by the increase in the inner radius of the obscuring material with incident luminosity, which arises from the sublimation of dust; by the gravitational potential of the black hole; by radiative feedback; or by the interplay between outflows and inflows. However, the lack of a large, unbiased and complete sample of accreting black holes, with reliable information on gas column density, luminosity and mass, has left the main physical mechanism that regulates obscuration unclear. Here we report a systematic multi-wavelength survey of hard-X-ray-selected black holes that reveals that radiative feedback on dusty gas is the main physical mechanism that regulates the distribution of the circumnuclear material. Our results imply that the bulk of the obscuring dust and gas is located within a few to tens of parsecs of the accreting supermassive black hole (within the sphere of influence of the black hole), and that it can be swept away even at low radiative output rates. The main physical driver of the differences between obscured and unobscured accreting black holes is therefore their mass-normalized accretion rate.

A prospective longitudinal study of postnatal dentoalveolar and palatal growth: The anatomical basis for CAD/CAM-assisted production of cleft-lip-palate feeding plates.

This study describes the dentoalveolar and palatal growth during the first months of life. Knowledge concerning this development is essential to avoid unwanted events such as mucosal ulcerations or restriction of growth when cleft-lip and palate (CLP) patients are treated. The results involve the generation of CAD/CAM CLP-feeding plates. Intraoral impressions from 32 healthy newborns were taken monthly for 5 months, supplemented by measurements of body weight, length, and occipital-frontal head circumference. The casts were digitalized, and two observers manually selected defined anatomical landmarks on virtual 3-D models. The distances between these landmarks were evaluted. Statistical analysis included an inter-rater agreement analysis and the determination of growth. In total, 213 casts were analyzed, with 65 models excluded because of inaccuracies in impression-taking or cast production. Overall longitudinal growth was 20.3%, whereas transversal growth reached a maximum of 21.1%. Vertical growth was 32.4% at the tuberal level. On the basis of these results, a semiautomated series of feeding plates allowing for monthly expansion could be generated. The acquired data serve as a useful reference for other pediatric and orthofacial investigations and treatments. One such application is the automated, fully virtual manufacture of CLP-feeding plates based on only one impression-taking. Our data reveal when caution is needed to prevent ulceration. The series of plates generated can minimize the time-consuming impression-taking and the production of further plaster models. The method of measurement is suitable for documentary purposes. Clin. Anat. 30:846-854, 2017. © 2017 Wiley Periodicals, Inc.

RapidNAM: generative manufacturing approach of nasoalveolar molding devices for presurgical cleft lip and palate treatment.

Nasoalveolar molding (NAM) is an accepted treatment strategy in presurgical cleft therapy. The major drawbacks of the treatment listed in the literature relate to the time of the treatment and the coordination of the required interdisciplinary team of therapists, parents, and patients. To overcome these limitations, we present the automated RapidNAM concept that facilitates the design and manufacturing process of NAM devices, and that allows the virtual modification and subsequent manufacture of the devices in advance, with a growth prediction factor adapted to the patient's natural growth. The RapidNAM concept involves (i) the prediction of three trajectories that envelope the fragmented alveolar segments with the goal to mimic a harmonic arch, (ii) the extrusion from the larger toward the smaller alveolar segment along the envelope curves toward the harmonic upper alveolar arch, and (iii) the generation of the NAM device with a ventilation hole, fixation pin, and fixation points for the nasal stents. A feasibility study for a vector-based approach was successfully conducted for unilateral and bilateral cleft lip and palate (CLP) patients. A comparison of the modified target models with the reference target models showed similar results. For further improvement, the number of landmarks used to modify the models was increased by a curve-based approach.

Pitfalls and solutions in virtual design of nasoalveolar molding plates by using CAD/CAM technology--A preliminary clinical study.

PURPOSE: Computer-assisted design and computer-aided manufacturing (CAD/CAM) technology in nasoalveolar molding (NAM) should save time and manpower and reduce family input in cases of cleft lip and palate. MATERIAL AND METHODS: Intraoral casts from 12 infants with complete unilateral cleft lip and palate were taken immediately after birth (T1) and after (T2) NAM treatment, digitalized, and transformed into STL data. The infants were randomized into Group 1 (n = 6) receiving conventional NAM treatment or Group 2 receiving CAD/CAM NAM (n = 6). We analyzed the following variables by using Geomagic software: intersegmental alveolar distance (ISAD); intersegmental lip distance (ISLD); nostril height cleft/noncleft (NHc/nc); nasal width cleft/noncleft (NWn/nc); and columella deviation angle (CDA). RESULTS: In both groups, all variables except NHnc and NWnc were changed significantly between T1 and T2. The analysis of the mean differences of the variables in Group 1 and 2 showed no significant differences, with a comparable incidence of clinical alterations such as skin or mucosal irritations. CONCLUSION: NAM plates can be produced virtually by using CAD/CAM technology. The CAD/CAM NAM results show no significant differences from the conventional technique. We present our clinically usable virtual CAD/CAM workflow for producing a basic NAM plate.

Extended hard-X-ray emission in the inner few parsecs of the Galaxy.

The Galactic Centre hosts a puzzling stellar population in its inner few parsecs, with a high abundance of surprisingly young, relatively massive stars bound within the deep potential well of the central supermassive black hole, Sagittarius A* (ref. 1). Previous studies suggest that the population of objects emitting soft X-rays (less than 10 kiloelectronvolts) within the surrounding hundreds of parsecs, as well as the population responsible for unresolved X-ray emission extending along the Galactic plane, is dominated by accreting white dwarf systems. Observations of diffuse hard-X-ray (more than 10 kiloelectronvolts) emission in the inner 10 parsecs, however, have been hampered by the limited spatial resolution of previous instruments. Here we report the presence of a distinct hard-X-ray component within the central 4 × 8 parsecs, as revealed by subarcminute-resolution images in the 20-40 kiloelectronvolt range. This emission is more sharply peaked towards the Galactic Centre than is the surface brightness of the soft-X-ray population. This could indicate a significantly more massive population of accreting white dwarfs, large populations of low-mass X-ray binaries or millisecond pulsars, or particle outflows interacting with the surrounding radiation field, dense molecular material or magnetic fields. However, all these interpretations pose significant challenges to our understanding of stellar evolution, binary formation, and cosmic-ray production in the Galactic Centre.