Reconstructive archaeology: in situ visualisation of previously excavated finds and features through an ongoing mixed reality process

Featured ApplicationThis automatic 3D reconstructive process currently underway supplies archaeologists with a mixed reality (MR) technique that allows them to interactively visualise 3D models representing formerly extracted finds, and to position such models over the features still present at the archaeological site.Archaeological excavation is a demolishing process. Rather few elements outlast extractive operations. Therefore, it is hard to visualise the precise location of unearthed finds at a previously excavated research area. Here, we present a mixed reality environment that displays in situ 3D models of features that were formerly extracted and recorded with 3D coordinates during unearthing operations. We created a tablet application that allows the user to view the position, orientation and dimensions of every recorded find while freely moving around the archaeological site with the device. To anchor the model, we used physical landmarks left at the excavation. A series of customised forms were created to show (onscreen) the different types of features by superimposing them over the terrain as perceived by the tablet camera. The application permits zooming-in, zooming-out, querying for specific artefacts and reading metadata associated with the archaeological elements. When at the office, our environment enables accurate visualisations of the 3D geometry concerning previously unearthed features and their spatial relationships. The application operates using the Swift programming language, Python scripts and ARKit technology. We present here an example of its use at Les Cottes, France, a palaeolithic site where thousands of artefacts are excavated out of six superimposed layers with a complex conformation.NWOVI.C.191.070Human Origin

Identification of general added mass distribution in nanorods from two-spectra finite data

Nanomechanical resonators consisting in one-dimensional vibrating structures have remarkable performance in detecting small adherent masses. The mass sensing principle is based on the use of the resonant frequency shifts caused by unknown attached masses. In spite of its importance in applications, few studies are available on this inverse problem. Dilena et al. (2019) presented a method for reconstructing a small mass distribution by using the first N resonant frequencies of the free axial vibration of a nanorod under clamped end conditions. In order to avoid trivial non-uniqueness when spectral data belonging to a single spectrum are used, the mass variation was supposed to be supported in half of the axis interval. In this paper, we remove this a priori assumption on the mass support, and we show how to extend the method to reconstruct a general mass distribution by adding to the input data the first N lower eigenvalues of the nanorod under clamped-free end conditions. The nanobeam is modelled using the modified strain gradient theory to account for the microstructure and size effects. The reconstruction is based on an iterative procedure which takes advantage of the closed-form solution available when the mass change is small, and turns out to be convergent under this assumption. The results of an extended series of numerical simulations support the theoretical results.The authors from Universidad Carlos III de Madrid wish to acknowledge Ministerio de Economía y Competitividad de España for the financial support, under Grants No. DPI2014-57989-P and PGC2018-098218-B-I00. The authors from University of Udine gratefully acknowledge the financial support of the National Research ProjectPRIN 2015TT JN95 Identification and monitoring of complex structural systems

Recovering added mass in nanoresonator sensors from finite axial eigenfrequency data

In this paper we present a method for solving a finite inverse eigenvalue problem arising in the determination of added distributed mass in nanoresonator sensors by measurements of the first N natural frequencies of the free axial vibration under clamped end conditions. The method is based on an iterative procedure that produces an approximation of the unknown mass density as a generalized Fourier partial sum of order N, whose coefficients are calculated from the first N eigenvalues. To avoid trivial non-uniqueness due to the symmetry of the initial configuration of the nanorod, it is assumed that the mass variation has support contained in half of the axis interval. Moreover, the mass variation is supposed to be small with respect to the total mass of the initial nanorod. An extended series of numerical examples shows that the method is efficient and gives excellent results in case of continuous mass variations. The determination of discontinuous coefficients exhibits no negligible oscillations near the discontinuity points, and requires more spectral data to obtain good reconstruction. A proof of local convergence of the iteration algorithm is provided for a family of finite dimensional mass coefficients. Surprisingly enough, in spite of its local character, the identification method performs well even for not necessarily small mass changes. To the authors' knowledge, this is the first quantitative study on the identification of distributed mass attached on nanostructures modelled within generalized continuum mechanics theories by using finite eigenvalue data

Hearing distributed mass in nanobeam resonators

One-dimensional vibrating nanostructures show remarkable performance in detecting small adherent masses added to a referential configuration. The mass sensing principle is based on measuring the resonant frequency shifts caused by the unknown attached masses. In spite of its important application in several fields, few studies have been devoted to this inverse eigenvalue problem. In this paper we have developed a distributed mass reconstruction method for initially uniform nanobeams based on measurements of the first lower resonant frequencies of the free bending vibration. Two main inverse problems are addressed. In the first problem, the mass variation is determined by using the first lower eigenfrequencies of a supported nanobeam, under the a priori assumption that the mass variation has support contained in half of the axis interval. In the second problem, we show that the a priori assumption can be removed, provided that the spectral input data include an additional set of first lower eigenfrequencies belonging to a second spectrum associated to different end conditions. The nanobeam is modelled using the modified strain gradient elasticity accounting for size effects. The reconstruction is based on an iterative procedure which takes advantage of a closed-form solution when the mass change is small, and shows to be convergent under this assumption and for smooth mass variation. The accuracy of the reconstruction deteriorates in presence of discontinuous mass variation. For these cases, a constrained least-squares optimization filtering shows to be very effective to reduce the spurious oscillations around the target coefficientThe authors from Universidad Carlos III de Madrid wish to acknowledge the Ministerio de Economía y Competitividad de España for the financial support under Grants numbers DPI2014-57989-P and PGC2018-098218-B-I00. The authors from University of Udine gratefully acknowledge the financial support of the National Research Project PRIN 2015TT JN95 "Identification and monitoring of complex structural systems". The authors wish to thank the two reviewers and the editor for constructive criticism and, in particular, for suggesting the experimental application reported at the end of Section 2

Contribution of ultrarare variants in mTOR pathway genes to sporadic focal epilepsies

Objective: We investigated the contribution to sporadic focal epilepsies (FE) of ultrarare variants in genes coding for the components of complexes regulating mechanistic Target Of Rapamycin (mTOR)complex 1 (mTORC1). Methods: We collected genetic data of 121 Italian isolated FE cases and 512 controls by Whole Exome Sequencing (WES) and single-molecule Molecular Inversion Probes (smMIPs) targeting 10 genes of the GATOR1, GATOR2, and TSC complexes. We collapsed \u201cqualifying\u201d variants (ultrarare and predicted to be deleterious or loss of function) across the examined genes and sought to identify their enrichment in cases compared to controls. Results: We found eight qualifying variants in cases and nine in controls, demonstrating enrichment in FE patients (P = 0.006; exact unconditional test, one-tailed). Pathogenic variants were identified in DEPDC5 and TSC2, both major genes for Mendelian FE syndromes. Interpretation: Our findings support the contribution of ultrarare variants in genes in the mTOR pathway complexes GATOR and TSC to the risk of sporadic FE and a shared genetic basis between rare and common epilepsies. The identification of a monogenic etiology in isolated cases, most typically encountered in clinical practice, may offer to a broader community of patients the perspective of precision therapies directed by the underlying genetic cause

Mutations in CYP2U1, DDHD2 and GBA2 genes are rare causes of complicated forms of hereditary spastic paraparesis

Complicated hereditary spastic paraplegias (HSP) are a heterogeneous group of HSP characterized by spasticity associated with a variable combination of neurologic and extra-neurologic signs and symptoms. Among them, HSP with thin corpus callosum and intellectual disability is a frequent subtype, often inherited as a recessive trait (ARHSP-TCC). Within this heterogeneous subgroup, SPG11 and SPG15 represent the most frequent subtypes. We analyzed the mutation frequency of three genes associated with early-onset forms of ARHSP with and without TCC, CYP2U1/SPG56, DDHD2/SPG54 and GBA2/SPG46, in a large population of selected complicated HSP patients by using a combined approach of traditional-based and amplicon-based high-throughput pooled-sequencing. Three families with mutations were identified, one for each of the genes analyzed. Novel homozygous mutations were identified in CYP2U1 (c.1A>C/p.Met1?) and in GBA2 (c.2048G>C/ p.Gly683Arg), while the homozygous mutation found in DDHD2 (c.1978G>C/p.Asp660His) had been previously reported in a compound heterozygous state. The phenotypes associated with the CYP2U1 and DDHD2 mutations overlap the SPG56 and the SPG54 subtypes, respectively, with few differences. By contrast, the GBA2 mutated patients show phenotypes combining typical features of both the SPG46 subtype and the recessive ataxia form, with marked intrafamilial variability thereby expanding the spectrum of clinical entities associated with GBA2 mutations. Overall, each of three genes analyzed shows a low mutation frequency in a general population of complicated HSP (<1% for either CYP2U1 or DDHD2 and approximately 2% for GBA2 ). These findings underline once again the genetic heterogeneity of ARHSP-TCC and the clinical overlap between complicated HSP and the recessive ataxia syndromes

International consensus recommendations for management of new onset refractory status epilepticus including febrile infection-related epilepsy syndrome: Statements and supporting evidence

Objective: This study was undertaken to develop consensus-based recommendations for the management of adult and pediatric patients with new onset refractory status epilepticus (NORSE)/febrile infection-related epilepsy syndrome (FIRES) based on best evidence and experience. Methods: The Delphi methodology was followed. A facilitator group of nine experts was established, who defined the scope, users, and suggestions for recommendations. Following a review of the current literature, recommendation statements concerning diagnosis, treatment, and research directions were generated, which were then rated on a scale of 1 (strongly disagree) to 9 (strongly agree) by a panel of 48 experts in the field. Consensus that a statement was appropriate was reached if the median score was ≥7 and inappropriate if the median score was ≤3. The analysis of evidence was mapped to the results of each statement included in the Delphi survey. Results: Overall, 85 recommendation statements achieved consensus. The recommendations are divided into five sections: (1) disease characteristics; (2) diagnostic testing and sampling; (3) acute treatment; (4) treatment in the postacute phase; and (5) research, registries, and future directions in NORSE/FIRES. The detailed results and discussion of all 85 statements are outlined herein. A corresponding summary of findings and practical flowsheets are presented in a companion article. Significance: This detailed analysis offers insight into the supporting evidence and the current gaps in the literature that are associated with expert consensus statements related to NORSE/FIRES. The recommendations generated by this consensus can be used as a guide for the diagnosis, evaluation, and management of patients with NORSE/FIRES, and for planning of future research

Consensus protocol for EEG and amplitude-integrated EEG assessment and monitoring in neonates

The aim of this work is to establish inclusive guidelines on electroencephalography (EEG) applicable to all neonatal intensive care units (NICUs). Guidelines on ideal EEG monitoring for neonates are available, but there are significant barriers to their implementation in many centres around the world. These include barriers due to limited resources regarding the availability of equipment and technical and interpretive round-the-clock personnel. On the other hand, despite its limitations, amplitude-integrated EEG (aEEG) (previously called Cerebral Function Monitor [CFM]) is a common alternative used in NICUs. The Italian Neonatal Seizure Collaborative Network (INNESCO), working with all national scientific societies interested in the field of neonatal clinical neurophysiology, performed a systematic literature review and promoted interdisciplinary discussions among experts (neonatologists, paediatric neurologists, neurophysiologists, technicians) between 2017 and 2020 with the aim of elaborating shared recommendations. A consensus statement on videoEEG (vEEG) and aEEG for the principal neonatal indications was established. The authors propose a flexible frame of recommendations based on the complementary use of vEEG and aEEG applicable to the various neonatal units with different levels of complexity according to local resources and specific patient features. Suggestions for promoting cooperation between neonatologists, paediatric neurologists, and neurophysiologists, organisational restructuring, and teleneurophysiology implementation are provided