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Orthogonal time frequency space modulation (OTFS) scheme establishes reliable communication in a rapidly time-varying wireless channel with a high Doppler spread. We design a low-complexity linear minimum mean squared error (LMMSE) receiver for practical-pulse-shaped multiple-input multiple-output (MIMO)-OTFS systems. The proposed receiver exploits the inherent channel sparsity and the channel-agnostic structure of matrices involved in the LMMSE receiver, and has only a log-linear complexity. It provides exactly the same solution, and hence the same bit error rate (BER), as that of the conventional LMMSE receiver with a cubic order of complexity. We also derive, by using the Taylor series expansion and the results from random matrix theory, a tight closed-form approximation for the post-processing signal-to-noise-plus-interference ratio (SINR) expression of the proposed receiver. This expression is derived by assuming imperfect receive channel state information. We show using extensive numerical investigations that the derived SINR expression, when averaged over multiple channel realizations, accurately characterizes the BER of a MIMO-OTFS system.

Mutations in SYNGAP1are a common genetic cause of intellectual disability (ID) and a risk factor for autism. SYNGAP1encodes a synaptic GTPase-activating protein (GAP) that has both signaling and scaffolding roles. Most pathogenic variants of SYNGAP1are predicted to result in haploinsufficiency. However, some affected individuals carry missense mutations in its calcium/lipid binding (C2) and GAP domains, suggesting that many clinical features result from loss of functions carried out by these domains. To test this hypothesis, we targeted the exons encoding the C2 and GAP domains of SYNGAP. Rats heterozygous for this deletion exhibit reduced exploration and fear extinction, altered social investigation, and spontaneous seizures—key phenotypes shared with Syngapheterozygous null rats. Together, these findings indicate that the reduction of SYNGAP C2/GAP domain function is a main feature of SYNGAP haploinsufficiency. This rat model provides an important system for the study of ID, autism, and epilepsy.

Background Hemipelvectomy is a major surgery most often performed for pelvic malignancy. These complex surgeries often involve dissection around major neurovascular bundle and resection of tumour being bone along with involved tissues. This may result in short and long term morbidities. There is very little literature about incidence of chronic pain after pelvic resections. We conducted a prospective study at a tertiary cancer hospital to assess the prevalence of chronic pain post hemipelvectomy.Method This is a single centre prospective observational study conducted over 30 months. Pain scores were recorded using Brief pain inventory (BPI) and pain detect questionnaire. The quality of life was assessed using musculoskeletal tumour society (MSTS) score. Intra-operative details like extent of surgical resection, nerves spared, details of intra-operative and post-operative analgesia were retrieved from the patient files. Data were analysed using SPSS 21 version.Results Neuropathic pain post hemipelvectomy was uncommon. The prevalence of mild to moderate somatic pain was around 30%. Functional limitation was minimal as assessed by BPI and MSTS score. A high incidence of numbness was seen to persist in and around the area of surgical incision (50%).Conclusion This is first study to report the incidence of chronic pain post hemipelvectomy done for pelvic tumour resections. Despite the extensive nature of resection involved, there is a low prevalence of neuropathic pain in this population. However, incidence of persistent somatic pain is high and there is a need for further studies for evaluating the causality

In this work, a computational fluid dynamics (CFD)-assisted optimization study has been carried out, implementing geometric design modifications in a biomass cook stove (BCS) to achieve uniform air–fuel distribution. The work has been divided into two parts. The first part deals with the numerical investigations of fluid phase hydrodynamics and air–fuel homogeneous phase combustion. Simulations have been performed for a wide range of air velocities to predict the roles of primary and secondary airflow in improving the spatial airflow uniformity inside the BCS. The homogeneous combustion simulations show linear dependence of power and temperature on the air velocity and air-to-fuel ratio. The results indicate that the most optimized power output and temperature values are achieved when the grate is placed at a height of 25 mm, and the orifice plate with 15 holes of 10 mm each is located at a height of 105 mm from the bottom of the cook stove.

In this study, we have developed a novel model to include the spatial heterogeneity for the combustion of volatiles in the presence of oxygen inside a biomass cookstove (BCS). Three-dimensional computational fluid dynamic simulations of BCS were done to evaluate the dynamics of spatial heterogeneity incurred during biomass combustion. The proposed methodology prescribes the mass release rate of the fuel as a dynamic boundary condition that evolves as per the changing temperature in the void spaces of the packed bed. The temporally evolving mass release rate due to the change in temperatures of the void spaces is calculated iteratively and set as the inlet boundary condition on the particle surfaces using an empirical correlation. The validation studies showed that the time-averaged outlet temperatures predicted from the model are in good agreement with the experimentally obtained values.

Land use changes have been recognized as one of the key ecological drivers in regulation of methane (CH4) consumption from dry upland soils. This study investigated the impact of land use changes and different soil depths (0–10, 10–20 and 20–30 cm) on soil physicochemical properties and methanotrophs abundance in dry tropical region of Vindhyan uplands. Four different land use types (agriculture land, mixed forest, savanna and natural forest) were selected for a comparative study. Among the different land uses and soil depths, results indicated significantly higher soil moisture (SM), organic-C, inorganic nutrients, water holding capacity (WHC) and methanotrophs abundance at 0–10 cm depth of natural forest compared to other sites. Across different land uses, number (8.11 × 107pmoAcopies g−1of dry soil) of methanotrophs isolated from the natural forest soil was statistically higher than the soils of other land use types. The variations in pmoAgene numbers across different land uses and soil depths were significant (P < 0.001). The pmoAgene numbers were positively correlated with soil C/N ratio (R2= 0.9233) and moisture (R2= 0.9675) contents. The decreasing order of pmoAgene abundance across different land uses was natural forest > mixed forest > savanna > agriculture land. The result suggest that land use changes (conversion of natural forest to agricultural land) alter the major soil properties (SM, WHC, organic matter, C/N ratio, etc.) and significantly reduce the methanotrophs and pmoAgene numbers. The land use management practices (application of bio-fertilizers in place of chemical fertilizers), especially for the degraded agricultural soils, could be beneficial option to mitigate the negative impacts on soil methanotrophs and their CH4sink activity in the upland soil of Vindhyan region.

Hundreds of clinics in India offer unproven stem cell therapies despite having remarkably stringent guidelines and regulations for fraudulent advertisements and clinical practice. We discuss the challenges with current regulations, how a recently proposed amendment may further legitimize unproven stem cell therapies, and discuss paths forward in a global context.

The present work discusses the findings obtained from simulations of semi solid die filling of a steering knuckle, prior to actual component development using in-house developed rheo pressure die casting system. Die filling capability of A356 Al alloy at semi-solid state has been investigated using commercial software Flow-3Dcast to optimise the pouring temperature of semi-solid slurry into the die cavity, while all other variables such as gating design, die preheat temperature and injection velocity are kept constant based on the prior knowledge obtained from trial numerical simulations and experimentation. Efforts have been made to nullify the essence of costly, time consuming experiments towards obtaining high-quality castings out of the findings obtained from numerical simulations. The optimum pouring temperature identified in the present study is 610 °C, which facilitates smoother slurry flow, minimum surface defect concentration, uniform temperature field and solid fraction distribution within the component cavity.

The mechanical and wear properties of three high carbon grades of cast iron alloys for brake application has been investigated in this work. The internal specification is to achieve the hardness of 190–260 BHN with 3.6–3.8 % carbon content and other alloying elements. The results show that the addition of Cu (0.5 %) and Cr (0.33 %) has only produced hardness of 170–180 BHN. The tensile strength and hardness decline by 15–20 % when graphite volume increases from 30 to 50 %. All the samples show both mass loss as well mass gains with uniform friction coefficient due to carbon layer deposit at the interface.

AbstractFilters have always remained a field of immense interest in the high frequency domain. Emerging applications such as wireless communications continue to challenge RF/microwave filters with ever more stringent requirements – high performance, smaller size, lightweight, and lower cost. In this paper we propose and investigate the application of electromagnetic bandgap (EBG) structures for improving the performance of a defected ground state (DGS) based low pass filter (LPF) with T-slot on the microstrip line. Whereas the T-slot and DGS are known to improve the roll off factor, EBG substrate further enhances this factor significantly. In our case the LPF with T-slot and square dumbles on DGS give a roll off of −29.3823 dB/GHz, on application of the EBG it improves to −31.7919 dB/GHz. Also, on applying the TE mode boundary condition along the vertical axis, we observe that the maximum attenuation is improved significantly from −60.65321 dB to −69.64911 dB.

Abstract: Phase morphology and crystallographic texture are important components of a solidification microstructure. Probability of nucleation of a nucleus is a strong function of local chemical & thermal conditions and its atomic orientation. Similarly, the growth kinetics for various crystal planes is dependent on its crystal orientation apart from local environmental conditions. The combined effects of nucleation & growth kinetics along with solidification conditions dictate the resulting microstructure of an alloy. In this study, various phases of a near eutectic Al-Si alloy are examined by serial sectioning and 3D reconstruction. A peculiar microstructure is observed in which primary silicon is present in the immediate proximity of primary aluminum. Observations through electron back scatter diffraction show that the microtexture of primary and eutectic Si is similar (with in a twin relation) and thus it is concluded that the formation of eutectic starts with eutectic Si forming on the primary Si.