An automated method for detection of layer activation order in information processing pathway of rat barrel cortex under mechanical whisker stimulation

Rodents perform object localization, texture and shape discrimination very precisely through whisking. During whisking, microcircuits in corresponding barrel columns get activated to segregate and integrate tactile information through the information processing pathway. Sensory signals are projected through the brainstem and thalamus to the corresponding ‘barrel columns’ where different cortical layers are activated during signal projection. Therefore, having precise information about the layer activation order is desirable to better understand this signal processing pathway. This work proposes an automated, computationally efficient and easy to implement method to determine the cortical layer activation from intracortically recorded local field potentials (LFPs) and derived current source density (CSD) profiles: 1. Barrel cortex LFPs are represented by a template of four subsequent events: small positive/negative (E1) → large negative (E2) → slow positive (E3)→ slow long negative (E4). The method exploits the layer specific characteristics of LFPs to obtain latencies of the individual events (E1–E4), then taking the latency of E2 for calculating the layer activation order. 2. The corresponding CSD profile is calculated from the LFPs and the first sink’s peak is considered as a reference point to calculate latencies and evaluate the layer activation order. Other reference points require manual calculation. Similar results of layer activation sequence are found using LFPs and CSDs. Extensive tests on LFPs recorded using standard borosilicate micropipettes demonstrated the method’s workability. An interpretation of layer activation order and CSD profiles on the basis of a simplified interacortical barrel column architecture is also provided

A WIRELESS SENSOR NETWORK BOARD FOR ENVIRONMENTAL MONITORING USING GNSS AND ANALOG TRIAXIAL ACCELEROMETER

Wireless Sensor Networks (WSNs) have attracted an increasing attention in recent years because of the large number of potential applications. They are used for collecting, storing and sharing data, for monitoring applications, surveillance purposes and much more. On the other hand GNSSs are used in various systems devoted to monitor different atmospheric parameters and to trace displacements of landslides and glaciers in severe environmental conditions and in all weather situations. A first example of low cost DGPS wireless sensor network was installed in 2009 on a serac located at 4100 m above a populated area in the Aosta Valley, Italy, and it is still operative. This work presents an evolution of the WSN node used in that systems with improved functionalities and flexibility. The electronic board developed as a multipurpose board to be used in different WSNs, has been completely redesigned as an open system in order to reduce its sizes and to be configured by only varying the firmware on the microcontroller. It allows different interfaces and is equipped with a recovery system, guaranteed by a watchdog chip which continuously monitor the onboard microcontroller. The board is equipped with both a GNSS module and an analog triaxial accelerometer in order to merge GNSS raw data and accelerometer data to keep track of both fast events and slow events. A free open source operative system has been ported on the microcontroller in order to perform multiple operations and to manage the communications between the network nodes with improved efficiency. The board firmware can be modified in real time using a custom bootloader to avoid difficult maintenance operations

Effect of Grafted Spiropyran on the Solubility and Film Properties of Photochromic Amylose

Four photochromic spiropyran-amylose (ASP) biobased polymers with different spiropyran (SP) grafting density, DS, ASP(10) (DS = 0.12), ASP(40) and ASP(40)PA(60) (DS = 0.40), and ASP(100) (DS = 0.97), are synthesized through azide-alkyne cycloaddition of an alkynyl-functional SP derivative onto C6-azidated-amylose (AN(3)), where the unconverted azide in ASP(40)PA(60), ASP(100), and the AN(3) precursor are quenched by clicking with propargyl alcohol (PA). All ASPs are poorly soluble in trifluoroethanol, ethanol, and water but soluble in dimethyl sulfoxide, N,N-dimethylformamide, and hexafluoroisopropanol irrespective of UV irradiation, switching reversibly the grafted SP into zwitterionic merocyanine (MC). Only ASP(10) and ASP(40) are slightly soluble in the low polarity tetrahydrofuran, with ASP(40) showing a marked photochromism and reduction of solubility on SP -> MC switching. The photochromism in solution is preserved in the solid state, although with significant differences between the still relatively fast SP -> MC photoisomerization and the much slower thermal retro-isomerization. The dynamics of both processes, evaluated in a thin spin-coated ASP(100) film and a thicker ASP(40) photoswitchable coating on glass and paper, is more clearly affected than in solution by the grafting density. Switching the nearly apolar SP into the zwitterionic MC does not significantly affect wettability of the slightly hydrophobic ASP(40) coating

Protein-like dynamical transition of hydrated polymer chains

Combining elastic incoherent neutron scattering experiments at different resolutions and molecular dynamics simulations, we report the observation of a protein-like dynamical transition in Poly(N-isopropylacrylamide) chains. We identify the onset of the transition at a temperature Td of about 225~K. Thanks to a novel global fit procedure, we find quantitative agreement between measured and calculated polymer mean-squared displacements at all temperatures and time resolutions. Our results confirm the generality of the dynamical transition in macromolecular systems in aqueous environments, independently of the internal polymer topology

Periodontal evaluation of palatally impacted maxillary canines treated by closed approach with ultrasonic surgery and orthodontic treatment: a retrospective pilot study

Aim of this study is the evaluation of the periodontal status of impacted canines treated by closed approach with ultrasonic surgery and orthodontic treatment compared with contralateral spontaneously erupted teeth. The periodontal conditions of the teeth adjacent to the canines (lateral incisors and first premolar) were also considered. 17 patients (9 females and 8 males; mean age: 15.2 years) with unilateral palatal impaction of maxillary canine were selected. All patients were treated by closed-flap surgery with ultrasonic instruments. Periodontal status was evaluated by assessing probing depth (PD), gingival recession and width of keratinized tissue (KT) 4.6 months after the end of the orthodontic treatment, on average. Test group was composed by impacted elements and adjacent teeth and control group by contralateral spontaneously erupted canines and adjacent teeth. Student's t-test was used to compare test and control group values of PD and width of KT. Significance threshold for Student's t-test was set at p < 0.05. The average probing depth values show no significant clinical differences between the test and control groups. Probing depths recorded at the mesiovestibular and distopalatal sides of the impacted canine were statistically significant compared to the control elements (p < 0.05). No gingival recession was detected on the treated canines. The measurement of KT did not differ significantly between the test and the control groups. In conclusion, the ultrasonic surgery for disinclusion associated with a closed approach and orthodontic traction allows the alignment of an impacted palatal canine without damaging the periodontium

Association between exposure to fine particulate matter and osteoporosis: a population-based cohort study

Long-term environmental air pollution exposure was associated with osteoporosis' risk in a cohort of women at high risk of fracture. Cortical sites seemed to be more susceptible to the exposure's effect

RFID technology applied to the glacial environment: MALATRA electronic system design and experimental data

The higher mountains of the Alps focus in the western part of Europe and favor a high concentration of glaciers in this area. The Aosta Valley region is surrounded by mountains, more than the 50% of its territory lying above 2000 m a.s.l. In the summer, most of the water supply of the region relies on the contribution given by snowmelt and, partially, by ice melt. Study of glacial processes is thus very important in this region. In this context the MALATRÀ project (led by Fondazione Montagna Sicura and Envisens Technologies) is created to develop a low-cost instrumentation capable of measuring with continuity the physical parameters of snow and ice. The instrumentation consists of a miniaturized electronic device (tag) equipped with sensors and placed inside an ovoidal small-dimension (48 mm diameter and 180 mm length) plastic capsule. Moreover, the implementation of radio frequency identification technology (RFID) allows remote communication from the surface with the tags placed deep into the glacier, thus saving time, effort and cost in collecting data. Tags allow communication at long distance working at 315 MHz frequency. At this step, the goal is to use such devices during the annual glaciological campaigns to measure the weight of the snowpack above the tag (with a pressure sensor), in order to derive the snow water equivalent (SWE) and temperature inside the ice. As a first step, the capsules will be coupled with ablation stakes installed in the ice, placed at the bottom of boreholes. Each capsule is uniquely identified by a code and can be located in a 3-D local system via radio using a localization algorithm under development. It is then, during the installation, georeferenced absolutely using a GNSS receiver. This functionality also allows for the glacier displacement measurements. Once the device has been identified, all the data stored in the internal memory can be remotely downloaded from the reader. At the current development stage the board is equipped with a precise thermometer (PT1000) and a pressure sensor to catch ice data, a magnetometer and a tri-axial accelerometer sensor to study the movement of the capsule within the ice. The performance of the system has been tested in the glacial environment with excellent results

Heterogeneity of Cortical Lesion Susceptibility Mapping in Multiple Sclerosis.

BACKGROUND AND PURPOSE: Quantitative susceptibility mapping has been used to characterize iron and myelin content in the deep gray matter of patients with multiple sclerosis. Our aim was to characterize the susceptibility mapping of cortical lesions in patients with MS and compare it with neuropathologic observations. MATERIALS AND METHODS: The pattern of microglial activation was studied in postmortem brain tissues from 16 patients with secondary-progressive MS and 5 age-matched controls. Thirty-six patients with MS underwent 3T MR imaging, including 3D double inversion recovery and 3D-echo-planar SWI. RESULTS: Neuropathologic analysis revealed the presence of an intense band of microglia activation close to the pial membrane in subpial cortical lesions or to the WM border of leukocortical cortical lesions. The quantitative susceptibility mapping analysis revealed 131 cortical lesions classified as hyperintense; 33, as isointense; and 84, as hypointense. Quantitative susceptibility mapping hyperintensity edge found in the proximity of the pial surface or at the white matter/gray matter interface in some of the quantitative susceptibility mapping–hyperintense cortical lesions accurately mirrors the microglia activation observed in the neuropathology analysis. CONCLUSIONS: Cortical lesion susceptibility maps are highly heterogeneous, even at individual levels. Quantitative susceptibility mapping hyperintensity edge found in proximity to the pial surface might be due to the subpial gradient of microglial activation