Packet scheduling in the presence of channel estimation error in multi-user OFDM wireless systems

In this paper, we investigate the effect of channel estimation error on the performance of channel aware techniques in a packet-based multi-user OFDM wireless system. To this end, we consider the use of two channel estimation schemes; one is a simple linear and the other is an optimum Wiener-type channel estimator. We examine the effect of channel impulse response (CIR) estimation error on coherent reception and the effect of signal-to-interference and noise ratio (SINR) estimation error on channel aware transmission techniques (e.g., packet scheduling). It is shown that the performance of coherent reception is relatively less susceptible to the CIR estimation error, but the performance of channel aware schemes can be very sensitive to the SINR estimation error. To alleviate this problem, we propose a robust scheduling scheme which can work without significant performance degradation even in the presence of large channel estimation error. Finally, we verify the performance of the proposed scheduling scheme by computer simulation.Ministry of Information & Communications, Kore

Mobile resistome of human gut and pathogen drives anthropogenic bloom of antibiotic resistance

BACKGROUND:The impact of human activities on the environmental resistome has been documented in many studies, but there remains the controversial question of whether the increased antibiotic resistance observed in anthropogenically impacted environments is just a result of contamination by resistant fecal microbes or is mediated by indigenous environmental organisms. Here, to determine exactly how anthropogenic influences shape the environmental resistome, we resolved the microbiome, resistome, and mobilome of the planktonic microbial communities along a single river, the Han, which spans a gradient of human activities. RESULTS:The bloom of antibiotic resistance genes (ARGs) was evident in the downstream regions and distinct successional dynamics of the river resistome occurred across the spatial continuum. We identified a number of widespread ARG sequences shared between the river, human gut, and pathogenic bacteria. These human-related ARGs were largely associated with mobile genetic elements rather than particular gut taxa and mainly responsible for anthropogenically driven bloom of the downstream river resistome. Furthermore, both sequence- and phenotype-based analyses revealed environmental relatives of clinically important proteobacteria as major carriers of these ARGs. CONCLUSIONS:Our results demonstrate a more nuanced view of the impact of anthropogenic activities on the river resistome: fecal contamination is present and allows the transmission of ARGs to the environmental resistome, but these mobile genes rather than resistant fecal bacteria proliferate in environmental relatives of their original hosts. Video abstract

Erythropoietin Reduces Death and Neurodevelopmental Impairment in Neonatal Hypoxic-Ischemic Encephalopathy

Purpose Erythropoietin (EPO) is a promising neuroprotective drug. We investigated whether EPO has beneficial effects on neurodevelopmental outcomes in infants with hypoxic-ischemic encephalopathy (HIE). Methods We retrospectively reviewed the data of 56 infants with HIE born at or after 35 weeks of gestation who were admitted to Inha University Hospital between 2012 and 2021. Patients were divided into two groups based on EPO use and compared. In the EPO group, patients were administered 1,000 U/kg of EPO on days 1, 2, 3, 5, and 7, starting within 24 hours after birth. The primary outcome was death or neurodevelopmental impairment (NDI) at the age of 12 months. Results EPO was administered to 38 infants, and 18 did not receive EPO. Only 37.5% of patients with HIE (21/56) and 60% of patients with moderate-to-severe HIE (21/35) received therapeutic hypothermia. Among all patients with HIE, death or NDI (21.1 % vs. 50.0%; odds ratio [OR], 0.09; 95% confidence interval [CI], 0.01 to 0.78; P=0.029) and brain injury on imaging (42.1% vs. 83.3%; OR, 0.16; 95% CI, 0.03 to 0.92; P=0.040) were significantly lower in the EPO group than in the control group. Among patients with moderate-to-severe HIE, brain injury on imaging (54.2% vs. 90.9%; OR, 0.04; 95% CI, 0.002 to 0.700; P=0.027) was significantly lower in the EPO group than in the control group. Conclusion EPO administration significantly reduced mortality and NDI in infants with HIE. EPO can be considered an adjunctive therapeutic agent for neonatal HIE

Spinal cord compression by B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and Burkitt lymphoma in a patient seropositive for human immunodeficiency virus: a case report

INTRODUCTION: Although non-Hodgkin’s lymphoma is one of the most common and frequently fatal of the acquired immune deficiency syndrome-defining illnesses, survival has improved significantly since the introduction of antiretroviral therapy. Patients with spinal cord compression resulting from non-Hodgkin’s lymphoma present with clinically acute or rapidly progressive neurologic deficits. The purpose of this case report is to present a case of a patient seropositive for human immunodeficiency virus with spinal cord compression due to B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and Burkitt lymphoma. CASE PRESENTATION: A 40-year-old Asian man, who was seropositive for human immunodeficiency virus, presented with progressive neurological deficits. Magnetic resonance images of his thoracic spine showed an epidural mass from T2 to T4, resulting in severe cord compression. Emergent surgical decompression and biopsy were performed, followed by palliative radiation therapy. The pathologic findings showed that the specimen was compatible with B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and Burkitt lymphoma. Palliative radiation therapy was performed; however, leptomeningeal seeding and pulmonary embolism led to his death. CONCLUSIONS: When a patient infected with human immunodeficiency virus presents with a rapidly progressive spinal tumor accompanying paraplegia, non-Hodgkin’s lymphoma should be considered, and surgical decompression should be weighed with respect to the patient’s general condition and the subtype/prognosis of the lymphoma

Measuring the social value of nuclear energy using contingent valuation methodology

As one of the promising energy sources for the next few decades, nuclear energy receives more attention than before as environmental issues become more important and the supply of fossil fuels becomes unstable. One of the reasons for this attention is based on the rapid innovation of nuclear technology which solves many of its technological constraints and safety issues. However, regardless of these rapid innovations, social acceptance for nuclear energy has been relatively low and unchanged. Consequently, the social perception has often been an obstacle to the development and execution of nuclear policy requiring enormous subsidies which are not based on the social value of nuclear energy. Therefore, in this study, we estimate the social value of nuclear energy-consumers’ willingness-to-pay for nuclear energy—using the Contingent Valuation Method (CVM) and suggest that the social value of nuclear energy increases approximately 68.5% with the provision of adequate information about nuclear energy to the public. Consequently, we suggest that the social acceptance management in nuclear policy development is important along with nuclear technology innovation

Tempcore Process Simulator to Analyze Microstructural Evolution of Quenched and Tempered Rebar

Featured Application Proposed process simulator can be widely applied to parameter design of industrial Tempcore process with reduced cost and time. Abstract Tempcore process simulator (TPS) has been developed in this study to analyze the microstructural evolution of quenched and tempered rebar. There has been an increasing need to relate the complex microstructures to the resulting properties of quenched and tempered rebar. However, information on such relationships typically requires precise thermal histories imposed on the workpiece. Therefore, TPS, capable of simulating the Tempcore process, has been developed to produce high-fidelity data. TPS mainly consists of a vacuum induction furnace, pilot rolling mill, box furnace, and cooling unit to simulate shop floor operations. A series of experimental tests were successfully carried out with various parameters, such as reheating temperature, water flow, water pressure, and cooling time. The effects of chemical compositions and cooling time on the microstructural evolution and mechanical properties of quenched and tempered rebar have been analyzed to validate the performance of TPS. The results show that TPS can simulate the Tempcore process with a high degree of fidelity and reliability.11Ysciescopu

Electric polarization enhancement in multiferroic CoCr2O4 crystals with Cr-site mixing

Single crystals of multiferroic cobalt chromite Co (Cr2-x Cox) O4 have been grown via several methods to have different Co3+ doping levels (x=0.0, 0.14, and 0.18). Under magnetic fields, all the crystals display electric polarization reversal below their spiral spin ordering temperatures. We find that both saturated electric polarization and magnetization under magnetic fields increase significantly with the increase in x. This result can be qualitatively explained by a broken balance between at least two electric polarization contributions existing in CoCr2 O4 and is expected to be useful in tailoring electric polarization in similar kinds of multiferroics. © 2009 American Institute of Physics.open222

Approximation of most penetrating particle size for fibrous filters considering Cunningham slip correction factor

In the estimation of the aerosol single fiber efficiency using fibrous filters, there is a size range, where the particles penetrate most effectively through the fibrous collectors, and corresponding minimum single fiber efficiency. For small particles in which the diffusion mechanism is dominant, the Cunningham slip correction factor (Cc) affects the single fiber efficiency and the most penetrating particle size (MPPS). Therefore, for accurate estimation, Cc is essential to be considered. However, many previous studies have neglected this factor because of its complexity and the associated difficulty in deriving the appropriate parameterization particularly for the MPPS. In this study, the expression for the MPPS, and the corresponding expression for the minimum single fiber efficiency are analytically derived, and the effects of Cc are determined. In order to accommodate the slip factor for all particle-size ranges, Cc is simplified and modified. Overall, the obtained analytical expression for the MPPS is in a good agreement with the exact solution