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Advances in deep learning have given rise to neural network models of the relationship between movement and brain activity that appear to far outperform prior approaches. Brain-computer interfaces (BCIs) that enable people with paralysis to control external devices, such as robotic arms or computer cursors, might stand to benefit greatly from these advances. We tested recurrent neural networks (RNNs) on a challenging nonlinear BCI problem: decoding continuous bimanual movement of two computer cursors. Surprisingly, we found that although RNNs appeared to perform well in offline settings, they did so by overfitting to the temporal structure of the training data and failed to generalize to real-time neuroprosthetic control. In response, we developed a method that alters the temporal structure of the training data by dilating/compressing it in time and re-ordering it, which we show helps RNNs successfully generalize to the online setting. With this method, we demonstrate that a person with paralysis can control two computer cursors simultaneously, far outperforming standard linear methods. Our results provide evidence that preventing models from overfitting to temporal structure in training data may, in principle, aid in translating deep learning advances to the BCI setting, unlocking improved performance for challenging applications.

The potentials of natural fibre encourage researchers to shift their interest from synthetic fibre. Numerous works have been done on the effective use of several natural fibres in manufacturing composites for automotive and structural applications. In the current investigation, effort has been made to evaluate the effect of the addition of glass fibre and influence of stacking sequence on mechanical properties of kenaf-/glass-reinforced hybrid composite laminates. Hybrid laminates with five different stacking sequences were fabricated by using hand layup technique. After curing, the fabricated composite laminates were cut to the dimension as per ASTM standard. Different tests have been carried out to determine tensile strength, flexural strength, and micro-hardness of fabricated laminates. Based on the findings, a sharp increase in mechanical properties is observed due to addition of glass fibre. Laminate with four layers of kenaf fibre shows minimum values of tensile strength, flexural strength and micro-hardness values. On subsequent addition of glass layer to the laminates, an increase in tensile strength from 35.78 to 166.38 MPa, flexural strength from 42.91 MPa to 155.83 MPa and micro-hardness value from 11.51 to 20.84 HV are reflected. To validate the experimental findings, numerical analysis has been made by using ANSYS R19.0 software. On comparison of experimental and numerical values, the deviation of the result is limited to 3%–12%. The morphology of fracture surfaces is also studied by using scanning electron microscope.

Intracortical brain-computer interfaces (iBCIs) provide people with paralysis a means to control devices with signals decoded from brain activity. Despite recent impressive advances, these devices still cannot approach able-bodied levels of control. To achieve naturalistic control and improved performance of neural prostheses, iBCIs will likely need to include proprioceptive feedback. With the goal of providing proprioceptive feedback via mechanical haptic stimulation, we aim to understand how haptic stimulation affects motor cortical neurons and ultimately, iBCI control. We provided skin shear haptic stimulation as a substitute for proprioception to the back of the neck of a person with tetraplegia. The neck location was determined via assessment of touch sensitivity using a monofilament test kit. The participant was able to correctly report skin shear at the back of the neck in 8 unique directions with 65% accuracy. We found motor cortical units that exhibited sensory responses to shear stimuli, some of which were strongly tuned to the stimuli and well modeled by cosine-shaped functions. We also demonstrated online iBCI cursor control with continuous skin-shear feedback driven by decoded command signals. Cursor control performance increased slightly but significantly when the participant was given haptic feedback, compared to the purely visual feedback condition.

Individuals living with paralysis or amputation can operate robotic prostheses using input signals based on their intent or attempt to move. Because sensory function is lost or diminished in these individuals, haptic feedback must be non-collocated. The intracortical brain computer interface (iBCI) has enabled a variety of neural prostheses for people with paralysis. An important attribute of the iBCI is that its input signal contains signal-independent noise. To understand the effects of signal-independent noise on a system with non-collocated haptic feedback and inform iBCI-based prostheses control strategies, we conducted an experiment with a conventional haptic interface as a proxy for the iBCI. Able-bodied users were tasked with locating an indentation within a virtual environment using input from their right hand. Non-collocated haptic feedback of the interaction forces in the virtual environment was augmented with noise of three different magnitudes and simultaneously rendered on users' left hands. We found increases in distance error of the guess of the indentation location, mean time per trial, mean peak absolute displacement and speed of tool movements during localization for the highest noise level compared to the other two levels. The findings suggest that users have a threshold of disturbance rejection and that they attempt to increase their signal-to-noise ratio through their exploratory actions., Accepted to ICRA 2020

Summary Decades after the motor homunculus was first proposed, it is still unknown how different body parts are intermixed and interrelated in human motor cortical areas at single-neuron resolution. Using multi-unit recordings, we studied how face, head, arm, and leg movements are represented in the hand knob area of premotor cortex (precentral gyrus) in people with tetraplegia. Contrary to traditional expectations, we found strong representation of all movements and a partially “compositional” neural code that linked together all four limbs. The code consisted of (1) a limb-coding component representing the limb to be moved and (2) a movement-coding component where analogous movements from each limb (e.g., hand grasp and toe curl) were represented similarly. Compositional coding might facilitate skill transfer across limbs, and it provides a useful framework for thinking about how the motor system constructs movement. Finally, we leveraged these results to create a whole-body intracortical brain-computer interface that spreads targets across all limbs.

Transient based technique is known as one of the most economical ways for pipeline condition assessment. This technique involves monitoring and analysing pressure transient profiles at multiple points in a distributed system. Its application is restricted due to its low spatial resolution (10 m). It is hypothesised that by increasing the number of pressure transducers and reducing the gauge length (distance between the transducers), the spatial resolution of the measurements would highly be improved. However, the deployment of pressure transducers is restricted to the location of the hydrants. In this paper, a submersible quasi-distributed optical fibre based pressure sensors were proposed, constructed and tested in laboratory to verify this concept. For this context, this paper describes the proposed optical device and presents some preliminary analysis and results obtained from a set of experiments. The experimental results show that using the quasi-distributed optical fibre based pressure transducers for pressure transient analysis can potentially detect small anomalies (200 mm) and measure the growth of the anomalies along a water pipe.

II-VI group quaternary semiconductor alloy thin films of cadmium zinc sulfoselenide (CdZnSSe) were prepared by chemical bath deposition technique on glass substrates. The deposition was carried out with various optimized deposition parameters such as concentration of precursor ions, deposition temperature, time, pH, etc. In order to obtain homogeneous thin films, triethanolamine (TEA) was used as complexing agent. A common cationic surfactant, cetyl-trimethylammoniumbromide (CTAB) was used as a capping agent. The as-deposited thin films were annealed at different temperatures (i.e. 100°, 300° and 500°C) and their structural and optical properties have been investigated by XRD, SEM, EDS and UV- visible optical absorption studies. The optical band gap energy was found to decrease from 2.21 to 2.01 eV, with increase in annealing temperature exhibiting a red shift.

Decades after the motor homunculus was first proposed, it is still unknown how different body parts are intermixed and interrelated in human motor cortex at single-neuron resolution. Using microelectrode arrays, we studied how face, head, arm and leg movements on both sides of the body are represented in hand knob area of precentral gyrus in people with tetraplegia. Contrary to the traditional somatotopy, we found strong representation of all movements. Probing further, we found that ipsilateral and contralateral movements, and homologous arm and leg movements (e.g. wrist and ankle), had a correlated representation. Additionally, there were neural dimensions where the limb was represented independently of the movement. Together, these patterns formed a “modular” code that might facilitate skill transfer across limbs. We also investigated dual-effector movement, finding that more strongly represented effectors suppressed the activity of weaker effectors. Finally, we leveraged these results to improve discrete brain-computer interfaces by spreading targets across all limbs.

The thin films of CdS(1-x)Se(x) were successfully deposited over glass substrates by chemical bath deposition technique. Cadmium acetate, thiourea and sodium selenosulfate were used as source materials for Cd(2+), S(2-) and Se(2-) ions, while 2-mercaptoethanol was used as capping agent. The various deposition conditions such as precursor concentration, deposition temperature, pH and deposition time were optimized for the deposition of CdS(1-x)Se(x) thin films of good quality and the films were annealed at 200° and 300 °C. The structural, morphological, chemical and optical properties were examined by various characterization techniques and discussed in detail. The optical band gap of CdS(1-x)Se(x) thin film samples were estimated and found in the range from 2.11 to 1.79 eV for as-deposited and annealed thin films.

The present paper reports the preparation of Cd 0.5 Pb 0.5 S thin films via a simple and inexpensive chemical bath deposition technique. Various preparation conditions were optimized for the deposition of good quality Cd 0.5 Pb 0.5 S thin films. The structural, morphological and optical properties of these films are discussed. The structural studies confirmed the polycrystalline nature of material with cubic structure. Using scanning electron microscopy, the surface morphology of the films was studied. The optical band gap of the film gets modified during annealing. The chemical composition of these thin films was studied by energy dispersive spectroscopy. The optical band gap energy for as-deposited and annealed Cd 0.5 Pb 0.5 S thin films were calculated and found in the range of 2.6 to 2.05 eV.

Over the past decades, chemical bath deposition (CBD) has proven its suitability and has established itself as one of the prominent techniques for depositing different metal chalcogenide semiconductor thin films via ion-by-ion or by adsorption of colloidal particles from the chemical bath on the substrate. It is a simple, cost-effective and convenient method for large-scale deposition and has recently received a surge of interest. This article reviews the research progress in various methods or techniques including CBD for the preparation and study of the properties of metal chalcogenides. Various parameters for efficient preparation and variation in structural, morphological, compositional, optical properties, etc. are also briefly discussed.

The thin films of cadmium zinc selenide $$(\hbox {Cd}_{0.5}\hbox {Zn}_{0.5}\hbox {Se})$$ were prepared over glass substrates by chemical bath deposition technique. The $$\hbox {Cd}_{0.5}\hbox {Zn}_{0.5}\hbox {Se}$$ thin films were doped with Gd at various doping values. The structural, morphological, compositional and optical properties were examined by XRD, SEM, EDX, UV–visible absorption and photoluminescence studies, respectively. Various structural parameters were calculated and the band gaps for these thin films were estimated and found in the range of 2.19–1.79 eV with respect to increasing doping values.

In this paper we report the best conditions for growth of thin films of cadmium selenide (CdSe). The chemical bath deposition technique was used to deposit thin solid films of CdSe on to glass substrates. In this technique, cadmium acetate and sodium seleno sulfate were used as Cd2+ and Se2− ion precursors, respectively. 2-Mercaptoethanol was used as a capping agent. X-ray diffraction, atomic-force microscopy, scanning electron microscopy, and energy-dispersive X-ray analysis were used to determine the structure, morphology, and elemental constitution of these films. Photoluminescence studies revealed the effect of capping agent on the size of the CdSe nanoparticles. The optical properties were investigated by use of UV–visible absorbance spectroscopy. On annealing at 573 K, the phase of as-deposited CdSe thin films was transformed from metastable cubic (zinc blende) to hexagonal (wurtzite). The band gap energy for bulk, capped, and annealed films was estimated, and found to be 1.7, 2.3, and 2.04 eV, respectively.

Zinc oxide thin films have been deposited on glass substrates by the chemical bath deposition method; a surfactant, cetyltrimethylammonium bromide (CTAB); was used as capping agent. The films were annealed at two different temperatures: 200 and 300 °C. The structural features were investigated by X-ray diffraction analysis which exhibited hexagonal wurtzite structures along with c-axis orientations. Crystallite size was estimated and found to be around 33–41 nm. The effect of post-deposition thermal annealing on the morphological and optical properties has been investigated by scanning electron microscopy and photoluminescence spectra at room temperature. The band gap energies of uncapped and CTAB-capped ZnO films were found to be 3.28 and 3.48 eV, respectively.

The synthesis and characterization of nanocrystalline CdSe thin solid films are reported in this article. Chemical bath deposition, a direct low-cost technique that involves a cadmium salt solution, a complexing agent, and a chalcogen (selenium) source, was used to prepare thin films of CdSe at a temperature 70°C (343 K) in a water bath. Commercially available microscope glass slides (7.5 cm × 2.5 cm × 2 mm) were used as substrates to deposit CdSe films. The characteristics of the prepared thin films were investigated in detail by measuring their optical properties, structural morphology and chemical composition. The films were characterized through x-ray diffraction (XRD), which indicates that the film is polycrystalline in nature. Absorption spectra of thin films have been recorded using a spectrophotometer. The spherical shaped clusters and the presence of elemental constituents were characterized using scanning electron microscopy (SEM) and energy-dispersive x-ray (EDX) analysis. The optical propertie...

Municipal solid waste (MSW) compost is increasingly used in agriculture as a soil conditioner but also as a fertilizer. Proponents of this practice consider it an important recycling tool since MSW would otherwise be land A»lled and critics are concerned with its often elevated metal concentrations. Large amounts of MSW compost are frequently used in agriculture to meet crop N requirements and for the addition of organic matter. The main concern is loading the soil with metals that can result in increased metal content of crops. Furthermore, in some cases, metals and excess nutrients can move through the soil proA»le into groundwater. Municipal solid waste compost has also been reported to have high salt concentrations, which can inhibit plant growth and negatively affect soil structure. A review of relevant agricultural studies is presented as well as recommendations for improving MSW compost quality. Its safe use in agriculture can be ensured with source separation (or triage of MSW to be composted) as well as the development and implementation of comprehensive industry standards.

Problem statement: Rapid urbanization and population growth are largely responsible for very high increasing rate of solid waste in the urban areas, its proper management and recycling is major problems of Municipal Corporation. The proposed study attempted to proper management, physicochemical analysis of Urban Solid Waste (USW) and its conversion to enriched compost by ecofriendly process. Approach: For this study, we used turned windrows method for composting of USW, microbial inoculums added uniformly and temperature, pH, moisture maintained throughout the composting process. The chemical composition of compost obtained at the end of the composting process compare to the United State Environmental Protection Agency (USEPA) standards. Results: A study in Jabalpur had shown the 47% of Urban Solid Waste (USW) were degradable and 53% non-degradable. The initial compositions of urban waste were indicates an organic carbon status of 38% with the C: N ratio of 950. The additives used in solid urban waste composting such as cow dung and green manure recorded organic carbon content of 25.60 and 34.60 and C:N ratio of 30.11 and 11.23. Conclusion: The results of the study clearly indicate that the recycling of solid urban waste can transform garbage or municipal solid waste to enriched composts. This is practical significance if adopted by urban farmers as a result of soil health and in turn the productivity of soil can be maintained for further agriculture.

Robotic systems, such as prosthetics and exoskeletons, offer people suffering from motor impairments a chance to regain lost physical functionality. However, the neural control that individuals are able to exert over these robots is currently limited. This is due to both lack of control authority in many degrees of freedom and insufficient sensory feedback through the human-robot interface. We propose that haptic feedback is paramount for accurate and efficient control of robots via brain-computer interfaces (BCIs). Skin stretch at the fingertip is a novel form of haptic feedback for improving BCI-based robot control. In this paper, we describe the design of a BCI-driven skin-stretch device, assess several control paradigms for this device, and evaluate its effectiveness in a small user study. We show that BCI-based movement-intent classification improved in the presence of skin-stretch feedback for 3 of 4 healthy individuals controlling a computer cursor via an inexpensive, commercial electroencephalography-based (EEG) BCI.

During robot-assisted minimally invasive surgery, teleoperation systems allow surgeons to perform operations at a distance via instruments inserted through small incisions in the body, thereby minimizing patient pain and recovery time. While the patient-side manipulator allows precise, dexterous gripping and manipulation by the surgical tools, current clinical systems provide the surgeon with limited haptic feedback about tool-environment interactions. This differs from direct grasp and manipulation of hand-held objects, during which we receive feedback that provides cues regarding object surface properties, slip, and load force. We use a custom research version of the da Vinci Surgical System to study the control of grip force during teleoperated manipulation of an elastic environment. We tested a placement task that involved stretching of a rubber band, with and without feedback of the patient-side load forces to the user. We hypothesized that there is greater coupling between the applied grip force and the patient-side load force when force feedback is provided, as is observed during direct manipulation of hand-held objects. With an experienced surgeon user, coupling between the applied grip force and the load force was greater with force feedback than without.

In the present paper we reported the method to prepare ZnO nanoparticles by alkaline precipitation method for the degradation of an azo dye. We have used ZnO nanoparticles assisted with UV light irradiation to investigate the photocatalytic degradation of azo dyes. The ZnO photocatalyst was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and photoluminescence.

The synthesis and characterization of nanocrystalline Cd0.5Zn0.5S thin solid films is reported in the present paper. Chemical bath deposition, a direct low cost technique that involves metal ions (Cd2+ and Zn2+) source, a complexing agent and a chalcogen (sulphur) source was used to prepare thin films of Cd0.5Zn0.5S at a temperature of 70°C (343 K), with pH of 11 and deposition time of 2.5 hours. The characteristics of the prepared Cd0.5Zn0.5S thin films were investigated by their structural and optical properties and the effect of annealing on these properties were also studied.

This paper demonstrates initial results with a novel instrument for nanoparticle detection and quantization, called the “qNano.” The qNano instrument provides a label-free method for detection of charged particles passing through a nanopore (a nanopore scale channel that separates two volumes) via electrophoresis. The instrument incorporates an elastomeric membrane in which a nano-scale pore has been produced by mechanical puncturing, and stretching of the membrane allows control of the nanopore size. Trans-membrane voltage drives electrophoresis and particle translocations through the nanopore, as measured by the ionic current that flows through the pore. Pressure control is also available to increase the rates of capture and translocation. We demonstrate quantization of liposome and polystyrene particles ranging from 200–400 nm. Capture rate (translocation events per second) is shown to be linear with respect to applied pressure and membrane stretching distance. Additionally, translocation event amplitude is shown to decrease with increasing pressure, but remains invariant to changes in the membrane stretching distance.

The present population based group comparison study was undertaken to study the circumstances, motivations and influencing factors for seeking abortion in women in Chandrapur District of Maharashtra. Participants of the study included 500 cases of induced abortion and the equal number of normal delivered women during the same period and in the same area as comparison group. Having two children, domestic problems and unwanted pregnancy were conditions acceptable to study subjects to terminate the pregnancy. Family and domestic problems, poor socio-economic status, short inter-pregnancy interval and completed family size were some of the important reasons quoted by study subjects for not desiring to continue the current pregnancy. Majority of the subjects felt that the decision to terminate or keep pregnancy is usually taken jointly by both the husband and wife. Family and domestic problems, poor socioeconomic status and short inter pregnancy interval were the important reasons quoted by abortion cases for seeking abortion in the current pregnancy. Only 1.80% of the cases reported failure of contraceptive method as a cause of seeking abortion services. In 78.4% of abortion cases as compared to 5.4% subjects from the comparison group, pregnancy was un-planned.

A multicentre parallel group study was carried out to compare the efficacy and safety of remoxipride, a new antipsychotic drug, with haloperidol in the treatment of acute schizophrenia. Patients were randomly assigned to the two groups and assessments were made under double-blind conditions. Treatment was preceded by a washout period and lasted 6 weeks. Eighty-nine consecutively admitted men and women meeting the Research Diagnostic Criteria for schizophrenia in an acute phase of the illness were treated with remoxipride 75–300 mg b.d. or haloperidol 5–20 mg b.d. The main assessments were changes in scores on the Brief Psychiatric Rating Scale, Krawiecka Rating Scale and Clinical Global Impression. Both neuroleptics produced clinical improvement but there were no significant differences in overall efficacy measurements between the two drugs. There were relatively few unwanted side-effects. There were significantly less extra-pyramidal symptoms and blurred vision with remoxipride, and less constipation with haloperidol. The results indicate that remoxipride is an effective antipsychotic drug with a low incidence of extrapyramidal side-effects.

One hundred and four cases of osteoradionecrosis (ORN) of the mandible following irradiation of head and neck cancer are reported.Conservative management for ORN failed in all cases. Indications of hemimandibulectomy included intractable pain, severe trismus, pathological fracture, oro-cutaneous fistula and persistent exposure of bone.Surgical approach was intra-oral in 100 cases and extra-oral in four. Immediate soft tissue reconstructions were carried out in 20 per cent cases. Post-operative complications included minor sepsis (8.6 per cent), major sepsis (2.9 per cent), haemorrhage (2.9 per cent) and fistula (3.8 per cent). Major complications occurred only in patients treated exclusively by external irradiation at doses equal to or higher than 65 Gy.Relief from pain and trismus was obtained and normal swallowing was established following radical surgery.

Mesophasic proliposomat system for levonorgestrel was developed and evaluated both in vitro and in vivo. The vesicles were mostly unilamellar, however, few vesicles were multilamellar which budded off spontaneously upon hydration. The release of drug from this system adhered to zero order kinetics. The effect of alcohols and volatile oils on transdermal flux was investigated. The flux was found to be the highest for alcohol, and followed by that for lemon oil. The in vivo studies indicate the requirement for a loading dose, since, a significant lag phase was observed before the therapeutic levels were reached. This system was, however, superior to the PEG-based ointment system which was employed as the control formulation. The results demonstrate the potential of proliposomal system for efficaceous transdermal delivery of hydrophobic drugs.

The efficacy and safety of remoxipride in the treatment of schizophrenia were compared with those of haloperidol in a multicentre double-blind 6-week study which was randomized with a parallel group design and was preceded by a washout period. Eighty-nine consecutively admitted men and women meeting the Research Diagnostic Criteria for schizophrenia in an acute phase of the illness were treated with remoxipride 75-300 mg twice daily or haloperidol 5-20 mg twice daily. The efficacy assessments were the Brief Psychiatric Rating Scale, Krawiecka Rating Scale, and Clinical Global Impression. Both antipsychotic drugs produced clinical improvement with no significant differences between the efficacy of the two drugs. There were relatively few side effects. There were significantly fewer extrapyramidal symptoms and instances of blurred vision with remoxipride and less constipation with haloperidol. The results indicate that remoxipride is as effective an antipsychotic as haloperidol. Remoxipride has an advantage over haloperidol in respect to extrapyramidal side effects.

Melt-spun fibers of isotactic polypropylene have been formed using specific combinations of shearing and elongational flow. Such rheological conditions were achieved with a take-up device capable of subjecting molten polymer filaments continuously to various combinations of torsional and elongational strains. Relationships were determined between mechanical properties of the resulting fibers and their molecular organizations. The results obtained indicated that these flow fields would produce fibers whose mean-preferred-chain-orientation directions ranged between being tilted radially from a direction parallel with the fiber axis (no torsional shear strain imposed) and having some additional tilt that is tangential with respect to the fiber circumference (some torsional shear strain imposed). It is not possible to resolve the observed helical chain tilts into contributions from crystalline and amorphous regions, respectively.

The dried ethanol extract of the husk of Paspalum scrobiculatum grain was given to psychotic patients. The trial was conducted by the double blind control, cross over method. The extract has been found to exert definite tranquillizing effect on patients. The only side effects noticed were tremors and rigidity, which were reversible. However, clinical trial with larger doses and for a longer period is necessary to assess its efficacy and safety in psychiatric patients.

In the present paper, cadmium zinc selenide (Cd0.5Zn0.5Se) thin films were deposited on glass substrates by chemical bath deposition with optimized deposition parameters. 2-mercaptoethanol was used as a capping agent. The as-deposited thin films were annealed at 300, 500 and 700 °C and then subjected to various structural, morphological and optical investigations. The effect of the presence of capping agent and annealing on these properties was discussed. The phenomenon of phase transformation occurred during annealing. The optical band gap energies were found in the range 2.37–1.7 eV with respect to the annealing temperatures.