Cumulant-Based Automatic Modulation Classification Over Frequency-Selective Channels

Automatic modulation classification (AMC), being an integral part of multi-standard communication systems, allows for the identification of modulation schemes of detected signals. The need for this type of blind modulation classification process can be evidently seen in areas such as interference identification and spectrum management. Consequently, AMC has been widely recognized as a key driving technology for military, security, and civilian applications for decades. A major challenge in AMC is the underlying frequency selectivity of the wireless channel, causing an increase in complexity of the classification process. Motivated by this practical concern, we propose the use of k-nearest neighbor (KNN) classifier based on higher-order of statistics (HOS), which are calculated as features to distinguish between different types of modulation types. The channel is assumed to b multipath frequency-selective and the modulation schemes considered are {2, 4, 8} phase-shift keying (PSK) and {16, 64, 256} quadrature amplitude modulation (QAM). The simulation results confirmed the superiority of this approach over existing methods

Performance analysis of 5-ary MUSA and SCMA for uplink transmission

Multiple access is one of the core technologies of wireless communications, which enables wireless base stations to deal with a large number of different users and provide the service for each of them at the same time.  Meeting the 5G challenges, non-orthogonal multiple access is the main concerned point in 5G technologies. In this paper, two types of non-orthogonal multiple access schemes, namely, 5-ary Multi User Shared Access (MUSA) and Sparse Code Multiple Access (SCMA), are studied. The Bit Error Rate performance (BER) analysis in terms of user overloading for an uplink 5-ary MUSA and SCMA systems are analyzed

Link between distal sensory polyneuropathy, insulin-like growth factor-I and bone mineral density in elderly diabetics

Background: The association between Distal Sensory Polyneuropathy (DSP) and systemic osteopenia was studied before in type 1 Diabetes Mellitus (DM), however, is not all clear, with scanty researches in type 2 DM. In addition, Insulin-like Growth Factor-I (IGF-1) could be the most important mediator of bone growth, and an important neurotrophic factor for peripheral sensory neurons. Therefore, the aim of this study was to study the association between bone mineral density (BMD) and DSP, in elderly patients with type 2 DM, and the link between IGF-1 and both BMD and DSP.Methods: Eighty eight elderly patients, aged ≥60 years, were involved in this case (43 diabetics with DSP and 17 diabetics without DSP) - control (28 non diabetics) study. BMD and IGF-1 were measured.  Results: There was no significant difference between cases and controls regarding T score of either lumbar spine or femoral neck or IGF-1 (P = 0.83, 0.96 and 0.17 consecutively). DM without DSP had higher IGF-1 than both DM with DSP& the control group (P = 0.011 and 0.010 consecutively). IGF-1 was a significant predictor of T score of both femoral neck and lumbar spine, only in the control group (P = 0.008 and <0.001 consecutively) (OR=1.44 and 2.4 consecutively) (CI=1.1-1.9 and 1.9-3.1 consecutively). Neither DSP nor IGF-1 was (were) a significant predictor of BMD in diabetics.Conclusion: There was no association between type 2 DM and BMD. IGF-1 was higher in diabetics without DSP than those with DSP or the control group. IGF-1 was a positive predictor of BMD only in the control group.

Biotic and abiotic retention, recycling and remineralization of metals in the ocean

Trace metals shape both the biogeochemical functioning and biological structure of oceanic provinces. Trace metal biogeochemistry has primarily focused on modes of external supply of metals from aeolian, hydrothermal, sedimentary and other sources. However, metals also undergo internal transformations such as abiotic and biotic retention, recycling and remineralization. The role of these internal transformations in metal biogeochemical cycling is now coming into focus. First, the retention of metals by biota in the surface ocean for days, weeks or months depends on taxon-specific metal requirements of phytoplankton, and on their ultimate fate: that is, viral lysis, senescence, grazing and/or export to depth. Rapid recycling of metals in the surface ocean can extend seasonal productivity by maintaining higher levels of metal bioavailability compared to the influence of external metal input alone. As metal-containing organic particles are exported from the surface ocean, different metals exhibit distinct patterns of remineralization with depth. These patterns are mediated by a wide range of physicochemical and microbial processes such as the ability of particles to sorb metals, and are influenced by the mineral and organic characteristics of sinking particles. We conclude that internal metal transformations play an essential role in controlling metal bioavailability, phytoplankton distributions and the subsurface resupply of metals

EARLY PREDICTORS OF RENAL DYSFUNCTION IN Β-THALASSEMIA MAJOR AND INTERMEDIA PATIENTS

Background: Better survival of thalassemia patients allowed previously unrecognized renal complications to emerge. Objectives: Assess prevalence and early predictors of renal dysfunction in young β-thalassemia major (β-TM) and intermedia (β-TI) patients. Subjects: 66 β-TM (group I), 26 β-TI (group II) Egyptian patients and 40 healthy controls. Methods: History, examination and investigations that included kidney function tests, serum ferritin, serum bicarbonate, plasma osmolality and urinary total proteins, microalbuminuria (MAU), N-acetyl-β-D-glucosaminidase (NAG), retinol binding protein (RBP), α-1 microglobulin, bicarbonate, osmolality, Creatinine clearance (CrCl), % fractional excretion of bicarbonate (% FE-HCO3). Results: The most common renal abnormality was proteinuria (71%), followed by increased urinary level of RBP (69.4%), NAG (58.1%), α-1 microglobulin (54.8%) and microalbumin (29%) and also decreased urinary osmolality (58.1%). Although serum creatinine and BUN were not statistically different between thalassemia patients and control, CrCl were significantly lowered in thalassemia patients. Total serum protein and albumin was significant lower in splenectomized β-TM, whereas urinary total protein and MAU were significantly increased in all thalassemia patients. NAG, RBP and α-1 microglobulin were negatively correlated with CrCl and positively correlated with serum ferritin and urinary total protein. Z-score analysis for discrimination of patients with renal dysfunction proved superiority of urine total protein and RBP. Comparative statistics of different frequencies revealed significant difference between the urinary total protein and both MAU and % FE-HCO3. Conclusion: Asymptomatic renal dysfunctions are prevalent in young β-TM and β-TI patients that necessitate regular screening and urinary total protein and RBP may be cost-effective for early detection

Noise uncertainty effect on multi-channel cognitive radio networks

Achieving high throughput is the most important goal of cognitive radio networks. The main process in cognitive radio is spectrum sensing that targets getting vacant channels. There are many sensing methods like matched filter, feature detection, interference temperature and energy detection which is employed in the proposed system; however, energy detection suffers from noise uncertainty. In this paper a study of throughput under noise fluctuation effect is introduced. The work in this paper proposes multi-channel system; the overall multi-channel throughput is studied under noise fluctuation effect. In addition, the proficiency of the network has been examined under different number of channels and sensing time with noise uncertainty

α-Globin Messenger Ribonucleic Acid as a Molecular Marker for Determining the Age of Human Blood Spots in Different Temperatures

Background: Analyzing recovered evidence, such as blood which is one of the most encountered types of biological evidence, can provide information to establish the definite time when a crime was committed. This study aims to investigate the time- and temperature-related effects on human bloodstain’s α-globin messenger RNA expression and to estimate the bloodstain’s age using α-globin mRNA. Methods: A total of 22 blood samples were collected from healthy middle-aged volunteers (12 women and 10 men). After preparation, the samples were exposed to temperatures of 4°C, 24°C, and 40°C. Next, the mRNA expression of the α-globin gene was quantified by real-time RT-PCR at different time intervals of 0, 30, 90, and 150 days.Results: The α-globin gene expression showed the highest mean values by 0 day and at 4°C and the lowest mean values by 150 days and at 40°C. Samples from male participants showed higher mean values of α-globin gene expression compared to their female counterparts. A significant negative correlation was detected between α-globin gene expression and time interval. Meanwhile, a regression equation was formulated to estimate the time interval using the α-globin gene concentration.Conclusion: α-Globin mRNA could be a useful marker to estimate the age of human blood spots

A nullimorphic ERLIN2 mutation defines a complicated hereditary spastic paraplegia locus (SPG18)

Hereditary Spastic Paraplegia (HSP) is a clinically and genetically heterogeneous group of neurological disorders that are characterized by progressive spasticity of the lower extremities. We describe an extended consanguineous Saudi family in which HSP is linked to SPG18, a previously reported autosomal recessive locus, and show that it is associated with a nullimorphic deletion of ERLIN2, a component of endoplasmic reticulum associated degradation. This finding adds to the growing diversity of cellular functions that are now known to be involved in the maintenance of the corticospinal tract neurons

Mitochondrial Superoxide Dismutase Overexpression and Low Oxygen Conditioning Hormesis Improve the Performance of Irradiated Sterile Males

The Sterile Insect Technique (SIT) is a successful autocidal control method that uses ionizing radiation to sterilize insects. However, irradiation in normal atmospheric conditions can be damaging for males, because irradiation generates substantial biological oxidative stress that, combined with domestication and mass-rearing conditions, may reduce sterile male sexual competitiveness and quality. In this study, biological oxidative stress and antioxidant capacity were experimentally manipulated in Anastrepha suspensa using a combination of low-oxygen conditions and transgenic overexpression of mitochondrial superoxide dismutase (SOD2) to evaluate their role in the sexual behavior and quality of irradiated males. Our results showed that SOD2 overexpression enhances irradiated insect quality and improves male competitiveness in leks. However, the improvements in mating performance were modest, as normoxia-irradiated SOD2 males exhibited only a 22% improvement in mating success compared to normoxia-irradiated wild type males. Additionally, SOD2 overexpression did not synergistically improve the mating success of males irradiated in either hypoxia or severe hypoxia. Short-term hypoxic and severe-hypoxic conditioning hormesis, per se, increased antioxidant capacity and enhanced sexual competitiveness of irradiated males relative to non-irradiated males in leks. Our study provides valuable new information that antioxidant enzymes, particularly SOD2, have potential to improve the quality and lekking performance of sterile males used in SIT programs

Authoritarianism, Populism, and the Global Retreat of Democracy: A Curated Discussion

To the surprise of many in the West, the fall of the USSR in 1991 did not lead to the adoption of liberal democratic government around the world and the much anticipated “end of history.” In fact, authoritarianism has made a comeback, and liberal democracy has been on the retreat for at least the last 15 years culminating in the unthinkable: the invasion of a democratic European country by an authoritarian regime. But why does authoritarianism continue to spread, not only as an alternative to liberal democracy, but also within many liberal democracies where authoritarian leaders continue to gain strength and popularity? In this curated piece, contributors discuss some of the potential contributions of management scholarship to understanding authoritarianism, as well as highlight a number of directions for management research in this area.publishedVersio