Methodology of using acoustic emissions for enhancing rodent behavioral analysis.

Rodent models of behavior used in the fields of neuroscience and psychology generate a wealth of multimodal data. For instance, as a rodent moves and behaves in its environment, muscle contractions apply subtle forces to any surface the animal contacts. These forces generate acoustic waves that propagate through the waveguide as Lamb and shear horizontal (SH) waves and contain information about the rodent's physiology, behavior, and underlying psychological state. If the information in these waves were to be tapped, it would provide a novel, non-invasive way to study rodent behavior. This article lays the foundations for using guided ultrasonic waves generated by a mouse's movement on an aluminum plate for detecting behavior and drawing inferences about acoustic startle responses. The experimental setup involves piezoelectric sensors capturing the waves generated by the rodent's movement, which are then stored as discrete acoustic emission (AE) hits using an amplitude threshold-based data acquisition system. This method of data acquisition ensures that data collection occurs only when the animal moves or behaves, and each movement/behavior is represented by values of features within the generated wavepackets (AE hits). Through open field tests with C57BL/6J mice, utilizing piezoelectric sensors and the DAQ system, it was observed that every movement/behavior of the animal generated Lamb wavepackets within the frequency range of 20 kHz to 100 kHz. Furthermore, rearing behavior in the animals also led to the generation of SH wavepackets in the frequency range of 75 kHz to 230 kHz. This criterion was subsequently employed to detect rearing behavior. In the acoustic startle response test, where the animals' responses to intense sound pulse were recorded, AE hits' features proved useful in quantifying the response. These experimental findings validate the proposed technology's practicality and demonstrate its capability to enhance studies of rodent behavior.

Label extension, single-arm, phase III study shows efficacy and safety of stempeucel® in patients with critical limb ischemia due to atherosclerotic peripheral arterial disease.

BACKGROUND: Peripheral arterial disease (PAD) of lower extremities comprises a clinical spectrum that extends from asymptomatic patients to critical limb ischemia (CLI) patients. 10% to 40% of the patients are at the risk of primary amputation. This study was planned in "no-option" patients of CLI due to atherosclerotic PAD to assess the efficacy and safety of pooled, allogeneic, adult human bone marrow-derived mesenchymal stromal cells which is already approved for marketing in India for CLI due to Buerger's disease. METHODS: This was a single-arm, multi-centric, phase III study where mesenchymal stromal cells was injected as 2 million cells/kg body weight in the calf muscle and around the ulcer. Twenty-four patients of lower extremity CLI due to PAD with Rutherford III-5 or III-6 and ankle-brachial pressure index ≤ 0.6 and having have at least one ulcer with area between 0.5 and 10 cm2 were included in the study. These patients were evaluated over 12 months from drug administration. RESULTS: Over a period of 12 months, statistical significant reduction of rest pain and ulcer size along with improvement in ankle-brachial pressure index and ankle systolic was observed. The quality of life of patients improved together with increase in total walking distance and major amputation-free survival time. CONCLUSION: Mesenchymal stromal cells may be a feasible option to treat "no-option" patients with atherosclerotic PAD. Trial registration This study is registered prospectively in National Institutes of Health and Clinical Trials Registry-India (CTRI) website: CTRI/2018/06/014436. Registered 6th June 2018. http://ctri.nic.in/Clinicaltrials/pmaindet2.php?trialid=24050&EncHid=&userName=stempeutics .

Independent Flexural Wave Frequency Conversion by a Linear Active Metalayer.

Wave frequency is a critical parameter for applications ranging from structural health monitoring, noise control, and medical imaging to quantum of energy in matter. Frequency conversion is an inevitable wave phenomenon in nonlinear or time-modulated media. However, frequency conversion in linear media holds the promise of breaking limits imposed by the physics laws of wave diffraction such as Snell's law and Rayleigh criterion. In this Letter, we physically introduce a linear active metalayer in a structural beam that can convert the wave frequency of an flexural incidence into arbitrary frequencies of transmitted waves, which is underpinned by time modulation of sensing signals and insensitive to incident amplitude. The active element, involving piezoelectric components and time-modulated transfer function, breaks energy conservation such that the generated harmonics can be fully decoupled, making the frequency conversion linear and independent. By leveraging the time-modulated unit, phase-gradient and frequency-gradient metalayers are proposed for frequency-converted wave steering and dynamic beam steering, respectively. The linear active metalayer proposed herein suggests a promising solution to fully control time-domain signals of flexural waves, in stark contrast with existing elastic metasurfaces, regardless of being passive or active.

Zooplankton diversity of Chikkadevarayana canal in relation to physico-chemical characteristics.

Plankton diversity and physico-chemical parameters are an important criterion for evaluating the suitability of water for irrigation and drinking purposes. In this study, we tried to assess zooplankton species richness, diversity and evenness to predict the state of Chickadevarayana canal water of Cauvery River according to physico-chemical parameters. A total of 51 taxa were recorded with 22 rotifers, 5 copepods, 6 cladocerans, 1 ostracoda and 17 protozoans. More number of zooplankton species were recorded in Darasaguppe (30) followed by Edmuri (26), Kennala (20), Pandavpura (19) and Gendehosahalli (16). Among the rotifers, Euchlanis sp. species was abundant (194). Acantholeberis curvirostris was predominant among cladocerans (970). Among copepods, numerical superiorities were found in the case Cyclops sp. Cypris sp. was recorded in the ostracoda. Centropyxis aculeate repeated abundance in protozoans (412). The water samples analyzed for temperature, pH, electrical conductivity, alkalinity, hardness, dissolved oxygen, phosphate, sulphate and nitrate did not indicate variation. The occurrence of Asplanchna herricki, Lacrymaria sp, Brachionus pala and Monostyla lunaris showed highest similarity of occurrence reaching above 90%. The study revealed that the presence of certain species like Monostyla, Lepadella, Leydigia, Keratella, Branchionus and Cypris species can be considered as a biological indicator for eutrophication.