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1.
Neural Netw ; 173: 106204, 2024 May.
Article En | MEDLINE | ID: mdl-38412738

We explore element-wise convex combinations of two permutation-aligned neural network parameter vectors ΘA and ΘB of size d. We conduct extensive experiments by examining various distributions of such model combinations parametrized by elements of the hypercube [0,1]d and its vicinity. Our findings reveal that broad regions of the hypercube form surfaces of low loss values, indicating that the notion of linear mode connectivity extends to a more general phenomenon which we call mode combinability. We also make several novel observations regarding linear mode connectivity and model re-basin. We demonstrate a transitivity property: two models re-based to a common third model are also linear mode connected, and a robustness property: even with significant perturbations of the neuron matchings the resulting combinations continue to form a working model. Moreover, we analyze the functional and weight similarity of model combinations and show that such combinations are non-vacuous in the sense that there are significant functional differences between the resulting models.


Neural Networks, Computer , Neurons , Neural Pathways/physiology , Magnetic Resonance Imaging , Brain
3.
J Neurol ; 270(5): 2531-2546, 2023 May.
Article En | MEDLINE | ID: mdl-36735057

Risdiplam is an oral, survival of motor neuron 2 (SMN2) pre-mRNA splicing modifier approved for the treatment of spinal muscular atrophy (SMA). SUNFISH (NCT02908685) Part 2, a Phase 3, randomized, double-blind, placebo-controlled study, investigated the efficacy and safety of risdiplam in type 2 and non­ambulant type 3 SMA. The primary endpoint was met: a significantly greater change from baseline in 32-item Motor Function Measure (MFM32) total score was observed with risdiplam compared with placebo at month 12. After 12 months, all participants received risdiplam while preserving initial treatment blinding. We report 24-month efficacy and safety results in this population. Month 24 exploratory endpoints included change from baseline in MFM32 and safety. MFM­derived results were compared with an external comparator. At month 24 of risdiplam treatment, 32% of patients demonstrated improvement (a change of ≥ 3) from baseline in MFM32 total score; 58% showed stabilization (a change of ≥ 0). Compared with an external comparator, a treatment difference of 3.12 (95% confidence interval [CI] 1.67-4.57) in favor of risdiplam was observed in MFM-derived scores. Overall, gains in motor function at month 12 were maintained or improved upon at month 24. In patients initially receiving placebo, MFM32 remained stable compared with baseline (0.31 [95% CI - 0.65 to 1.28]) after 12 months of risdiplam; 16% of patients improved their score and 59% exhibited stabilization. The safety profile after 24 months was consistent with that observed after 12 months. Risdiplam over 24 months resulted in further improvement or stabilization in motor function, confirming the benefit of longer-term treatment.


Muscular Atrophy, Spinal , Spinal Muscular Atrophies of Childhood , Humans , Spinal Muscular Atrophies of Childhood/drug therapy , Muscular Atrophy, Spinal/genetics , Pyrimidines/adverse effects , Azo Compounds/adverse effects
4.
J Synchrotron Radiat ; 30(Pt 1): 258-266, 2023 Jan 01.
Article En | MEDLINE | ID: mdl-36601945

As part of its Extremely Brilliant Source (EBS) upgrade project, the ESRF's BM29 BioSAXS beamline was subject to a significant upgrade and refurbishment. In addition to the replacement of the beamline's original bending magnet source by a two-pole wiggler, leading to an increase in brilliance by a factor of 60, the sample environment of the beamline was almost completely refurbished: a vacuum-compatible Pilatus3 X 2M with a sensitive area of 253.7 mm × 288 mm and frame rates up to 250 Hz was installed, increasing the active area available and thus the q-scaling of scattering images taken; the sample changer was replaced with an upgraded version, allowing more space for customizable sample environments and the installation of two new sample exposure units; the software associated with the beamline was also renewed. In addition, the layout and functionality of the BSXCuBE3 (BioSAXS Customized Beamline Environment) data acquisition software was redesigned, providing an intuitive `user first' approach for inexperienced users, while at the same time maintaining more powerful options for experienced users and beamline staff. Additional features of BSXCuBE3 are queuing of samples; either consecutive sample changer and/or SEC-SAXS (size-exclusion chromatography small-angle X-ray scattering) experiments, including column equilibration were also implemented. Automatic data processing and analysis are now managed via Dahu, an online server with upstream data reduction, data scaling and azimuthal integration built around PyFAI (Python Fast Azimuthal Integration), and data analysis performed using the open source FreeSAS. The results of this automated data analysis pipeline are displayed in ISPyB/ExiSAXS. The upgraded BM29 has been in operation since the post-EBS restart in September 2020, and here a full description of its new hardware and software characteristics together with examples of data obtained are provided.


Robotics , Synchrotrons , Humans , X-Ray Diffraction , Scattering, Small Angle , Software , Data Collection
6.
J Synchrotron Radiat ; 29(Pt 2): 581-590, 2022 Mar 01.
Article En | MEDLINE | ID: mdl-35254323

ID23-2 is a fixed-energy (14.2 keV) microfocus beamline at the European Synchrotron Radiation Facility (ESRF) dedicated to macromolecular crystallography. The optics and sample environment have recently been redesigned and rebuilt to take full advantage of the upgrade of the ESRF to the fourth generation Extremely Brilliant Source (ESRF-EBS). The upgraded beamline now makes use of two sets of compound refractive lenses and multilayer mirrors to obtain a highly intense (>1013 photons s-1) focused microbeam (minimum size 1.5 µm × 3 µm full width at half-maximum). The sample environment now includes a FLEX-HCD sample changer/storage system, as well as a state-of-the-art MD3Up high-precision multi-axis diffractometer. Automatic data reduction and analysis are also provided for more advanced protocols such as synchrotron serial crystallographic experiments.


Lenses , Synchrotrons , Crystallography, X-Ray , Data Collection , Macromolecular Substances/chemistry
7.
J Synchrotron Radiat ; 26(Pt 2): 393-405, 2019 Mar 01.
Article En | MEDLINE | ID: mdl-30855248

MXCuBE2 is the second-generation evolution of the MXCuBE beamline control software, initially developed and used at ESRF - the European Synchrotron. MXCuBE2 extends, in an intuitive graphical user interface (GUI), the functionalities and data collection methods available to users while keeping all previously available features and allowing for the straightforward incorporation of ongoing and future developments. MXCuBE2 introduces an extended abstraction layer that allows easy interfacing of any kind of macromolecular crystallography (MX) hardware component, whether this is a diffractometer, sample changer, detector or optical element. MXCuBE2 also works in strong synergy with the ISPyB Laboratory Information Management System, accessing the list of samples available for a particular experimental session and associating, either from instructions contained in ISPyB or from user input via the MXCuBE2 GUI, different data collection types to them. The development of MXCuBE2 forms the core of a fruitful collaboration which brings together several European synchrotrons and a software development factory and, as such, defines a new paradigm for the development of beamline control platforms for the European MX user community.

8.
Orv Hetil ; 160(13): 502-508, 2019 Mar.
Article Hu | MEDLINE | ID: mdl-30907098

INTRODUCTION: Prognostic impact of the detection of minimal residual disease (MRD) in multiple myeloma (MM) has been confirmed in numerous studies. AIM: Retrospective examination of our patient database (107 newly diagnosed multiple myelomas between 2007 and 2017). Flow cytometry (FCM) was performed as MRD assessment. METHOD: MRD assessment was performed in 56 patients (median age: 68 years), after induction treatment of multiple myeloma. The treatment contained bortezomib in 91%, autologous haematopoetic stem cell transplantation (ASCT) was perfomed in 50%. MRD detection was performed on bone marrow samples, predominantly in our hospital (BD FACScan, 3 colour, panel: CD38, CD138, CD19, CD45, CD56, CD28, CD117, cyKappa, cyLambda, 100 000 events). STATISTICAL ANALYSIS: SPSS 13.0. RESULTS: The progression-free survival (PFS) and the overall survival (OS) were significantly longer in MRD negative (n = 22) patients (PFS: 54 months, OS: 79% after 5 years) than MRD positive patients (n = 34, PFS: 22 months, OS 21% after 5 years, p = 0.001). Patients achieving complete response (CR) (n = 29) have different PFS (MRD negative CR: 60 months, MRD positive CR: 21 months, p<0.001). Patents achiving MRD negative very good partial response (n = 5) have similar PFS (54 months) as patients with MRD negative CR. The longest PFS (68 months) was observed in MRD negative patients, after ASCT (n = 11), while the PFS was significantly (p<0.001) shorter in patients who were MRD positive after ASCT (n = 18, PFS: 25 months), similarly in MRD positive patients without ASCT (n = 15, PFS 21 months). Cox regression analysis (stage, cytogenetic risk, ASCT) confirmed that MRD is an independent prognostic factor of PFS and OS. We did not find significant relationship between MRD and stage, cytogenetic risk, number of treatment cycles, ASCT. CONCLUSIONS: The depth of response after induction treatment of MM is an independent predictor of survival. MRD assessment with FCM is recommended to define response. Consideration of maintenance treatment in MRD positive patients and eradication of MRD are also recommended. Orv Hetil. 2019; 160(13): 502-508.


Multiple Myeloma/therapy , Neoplasm, Residual/diagnosis , Aged , Bortezomib/therapeutic use , Flow Cytometry , Hematopoietic Stem Cell Transplantation/statistics & numerical data , Humans , Retrospective Studies , Transplantation, Autologous/statistics & numerical data , Treatment Outcome
9.
J Synchrotron Radiat ; 25(Pt 4): 1249-1260, 2018 Jul 01.
Article En | MEDLINE | ID: mdl-29979188

ID30B is an undulator-based high-intensity, energy-tuneable (6.0-20 keV) and variable-focus (20-200 µm in diameter) macromolecular crystallography (MX) beamline at the ESRF. It was the last of the ESRF Structural Biology Group's beamlines to be constructed and commissioned as part of the ESRF's Phase I Upgrade Program and has been in user operation since June 2015. Both a modified microdiffractometer (MD2S) incorporating an in situ plate screening capability and a new flexible sample changer (the FlexHCD) were specifically developed for ID30B. Here, the authors provide the current beamline characteristics and detail how different types of MX experiments can be performed on ID30B (http://www.esrf.eu/id30b).

10.
Acta Crystallogr D Struct Biol ; 73(Pt 10): 829-840, 2017 Oct 01.
Article En | MEDLINE | ID: mdl-28994412

Most of the sample holders currently used in macromolecular crystallography offer limited storage density and poor initial crystal-positioning precision upon mounting on a goniometer. This has now become a limiting factor at high-throughput beamlines, where data collection can be performed in a matter of seconds. Furthermore, this lack of precision limits the potential benefits emerging from automated harvesting systems that could provide crystal-position information which would further enhance alignment at beamlines. This situation provided the motivation for the development of a compact and precise sample holder with corresponding pucks, handling tools and robotic transfer protocols. The development process included four main phases: design, prototype manufacture, testing with a robotic sample changer and validation under real conditions on a beamline. Two sample-holder designs are proposed: NewPin and miniSPINE. They share the same robot gripper and allow the storage of 36 sample holders in uni-puck footprint-style pucks, which represents 252 samples in a dry-shipping dewar commonly used in the field. The pucks are identified with human- and machine-readable codes, as well as with radio-frequency identification (RFID) tags. NewPin offers a crystal-repositioning precision of up to 10 µm but requires a specific goniometer socket. The storage density could reach 64 samples using a special puck designed for fully robotic handling. miniSPINE is less precise but uses a goniometer mount compatible with the current SPINE standard. miniSPINE is proposed for the first implementation of the new standard, since it is easier to integrate at beamlines. An upgraded version of the SPINE sample holder with a corresponding puck named SPINEplus is also proposed in order to offer a homogenous and interoperable system. The project involved several European synchrotrons and industrial companies in the fields of consumables and sample-changer robotics. Manual handling of miniSPINE was tested at different institutes using evaluation kits, and pilot beamlines are being equipped with compatible robotics for large-scale evaluation. A companion paper describes a new sample changer FlexED8 (Papp et al., 2017, Acta Cryst., D73, 841-851).


Crystallography/instrumentation , Equipment Design , Robotics/instrumentation , Sample Size , Synchrotrons
11.
Acta Crystallogr D Struct Biol ; 73(Pt 10): 841-851, 2017 Oct 01.
Article En | MEDLINE | ID: mdl-28994413

Automated sample changers are now standard equipment for modern macromolecular crystallography synchrotron beamlines. Nevertheless, most are only compatible with a single type of sample holder and puck. Recent work aimed at reducing sample-handling efforts and crystal-alignment times at beamlines has resulted in a new generation of compact and precise sample holders for cryocrystallography: miniSPINE and NewPin [see the companion paper by Papp et al. (2017, Acta Cryst., D73, 829-840)]. With full data collection now possible within seconds at most advanced beamlines, and future fourth-generation synchrotron sources promising to extract data in a few tens of milliseconds, the time taken to mount and centre a sample is rate-limiting. In this context, a versatile and fast sample changer, FlexED8, has been developed that is compatible with the highly successful SPINE sample holder and with the miniSPINE and NewPin sample holders. Based on a six-axis industrial robot, FlexED8 is equipped with a tool changer and includes a novel open sample-storage dewar with a built-in ice-filtering system. With seven versatile puck slots, it can hold up to 112 SPINE sample holders in uni-pucks, or 252 miniSPINE or NewPin sample holders, with 36 samples per puck. Additionally, a double gripper, compatible with the SPINE sample holders and uni-pucks, allows a reduction in the sample-exchange time from 40 s, the typical time with a standard single gripper, to less than 5 s. Computer vision-based sample-transfer monitoring, sophisticated error handling and automatic error-recovery procedures ensure high reliability. The FlexED8 sample changer has been successfully tested under real conditions on a beamline.


Crystallography/instrumentation , Crystallography/economics , Equipment Design , Proteins/chemistry , Robotics/economics , Robotics/instrumentation , Specimen Handling , Temperature , Time Factors
12.
Acta Crystallogr D Struct Biol ; 72(Pt 8): 966-75, 2016 08.
Article En | MEDLINE | ID: mdl-27487827

Automation of the mounting of cryocooled samples is now a feature of the majority of beamlines dedicated to macromolecular crystallography (MX). Robotic sample changers have been developed over many years, with the latest designs increasing capacity, reliability and speed. Here, the development of a new sample changer deployed at the ESRF beamline MASSIF-1 (ID30A-1), based on an industrial six-axis robot, is described. The device, named RoboDiff, includes a high-capacity dewar, acts as both a sample changer and a high-accuracy goniometer, and has been designed for completely unattended sample mounting and diffraction data collection. This aim has been achieved using a high level of diagnostics at all steps of the process from mounting and characterization to data collection. The RoboDiff has been in service on the fully automated endstation MASSIF-1 at the ESRF since September 2014 and, at the time of writing, has processed more than 20 000 samples completely automatically.


Crystallography, X-Ray/instrumentation , Proteins/chemistry , Animals , Bacillus/chemistry , Bacterial Proteins/chemistry , Cattle , Crystallography, X-Ray/economics , Crystallography, X-Ray/methods , Equipment Design , Robotics , Software , Thermolysin/chemistry , Trypsin/chemistry
13.
Acta Crystallogr D Struct Biol ; 72(Pt 4): 454-66, 2016 Apr.
Article En | MEDLINE | ID: mdl-27050125

Currently, macromolecular crystallography projects often require the use of highly automated facilities for crystallization and X-ray data collection. However, crystal harvesting and processing largely depend on manual operations. Here, a series of new methods are presented based on the use of a low X-ray-background film as a crystallization support and a photoablation laser that enable the automation of major operations required for the preparation of crystals for X-ray diffraction experiments. In this approach, the controlled removal of the mother liquor before crystal mounting simplifies the cryocooling process, in many cases eliminating the use of cryoprotectant agents, while crystal-soaking experiments are performed through diffusion, precluding the need for repeated sample-recovery and transfer operations. Moreover, the high-precision laser enables new mounting strategies that are not accessible through other methods. This approach bridges an important gap in automation and can contribute to expanding the capabilities of modern macromolecular crystallography facilities.


Automation, Laboratory/methods , Crystallography, X-Ray/methods , DNA Glycosylases/chemistry , Lasers , Automation, Laboratory/instrumentation , Crystallography, X-Ray/instrumentation , Humans
14.
Learn Mem ; 14(11): 732-44, 2007 Nov.
Article En | MEDLINE | ID: mdl-18007017

Comparative neuroanatomy suggests that the CA3 region of the mammalian hippocampus is directly homologous with the medio-dorsal pallium in birds and reptiles, with which it largely shares the basic organization of primitive cortex. Autoassociative memory models, which are generically applicable to cortical networks, then help assess how well CA3 may process information and what the crucial hurdles are that it may face. The analysis of such models points at spatial memories as posing a special challenge, both in terms of the attractor dynamics they can induce and how they may be established. Addressing such a challenge may have favored the evolution of elements of hippocampal organization observed only in mammals.


Hippocampus/cytology , Hippocampus/physiology , Memory/physiology , Space Perception/physiology , Animals , Humans
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