Wall Compensation for Ultra Wideband Applications

Due to their low frequency contents, ultra wideband (UWB) signals have the ability to penetrate walls and obstacles. As the signal propagates through these obstacles, it gets attenuated, slows down, and gets dispersed. This paper demonstrates wall compensation for through-wall imaging, localization and communication receiver design purposes by first characterizing wave propagation through various building materials in the UWB frequency range. Knowledge of the walls obtained from the wall characterization is used to estimate and correct the position accuracy of a target object located behind the walls using three proposed methods namely; constant amplitude and delay (CDL), frequency dependent data (FFD), and data fitting methods (FIT). The obtained results indicated relatively acceptable measure of wall compensation for the three methods. Results from such work provide insight on how to develop algorithms for effective target position estimation in imaging and localization applications. They are also useful for channel modelling and link budget analysis

The case of oncogenic hypophosphatemic osteomalacia

Osteomalacia is a systemic bone disease, characterized by an excessive accumulation of non-mineralized osteoid and an imbalance in the organic matrix formation and mineralization. A rare cause of disease is tumor-induced osteomalacia, most often due to phosphaturic mesenchymal tumors (PMT). Usually there are benign small tumors, affecting the soft tissues and bones of any location. The basic pathogenesis of underlying oncogenic osteomalacia is a decreased renal tubular reabsorption of phosphate consequent to hyperproduction of fibroblast growth factor 23 in PMT. Clinical features are nonspecific, the average period from the symptoms onset to diagnosis reaches 3 years and at least 5 years before surgical treatment. Finding the tumour is crucial, as complete removal is curative. We present a clinical case of tumor-induced osteomalacia due to PMT required the complex differential diagnosis with other rare diseases

Hepatitis C Virus Antibodies Among Blood Donors in Jos, Nigeria

Background: Hepatitis C virus (HCV) is one of the hepatitis agents known to be transmitted through blood and blood products. Hepatitis C virus has been implicated as a major cause of chronic liver disease and hepatocellular carcinoma worldwide. This study was, therefore, undertaken with the objective of determining the sero-prevalence of HCV antibodies among blood donors in the central city of Jos, Nigeria. Method: A total of two hundred blood donors were recruited from three hospitals within Jos metropolis. Sera from all subjects were tested for Hepatitis C virus antibodies using a second generation enzyme linked immunosorbent assay (ELISA). Results: Ninety five percent (95%)of the blood donors were males and most of them were aged between 21 and 50years. Twelve (6.0%)of the blood donors were anti-HCV seropositive and all of them males. Conclusion: There is an urgent need to introduce routine screening of blood donors for Hepatitis C virus markers in centers where this is not currently been practiced. This will reduce the risk of transfusion-associated hepatitis C infection and its complications in Nigeria

Comparative Analysis of Percutaneous Drainage versus Operative Drainage of Intra-Abdominal Abscesses in a Resource-Limited Setting: The Tanzanian Experience

Background: Intra-abdominal abscesses (IAAs) are a major cause of morbidity and mortality worldwide. While image-guided percutaneous abscess drainage (PAD) has become the standard of care in many countries, over half of the global population does not have access to interventional radiology (IR) and are left with surgery as the only option for source control. Objective: The purpose of this study is to evaluate the development, implementation, and role of a PAD service in a resource-limited setting. Method: A retrospective cohort study was performed on all patients who underwent percutaneous or surgical abscess drainage (SAD) of IAAs at Tanzania’s national referral hospital from 10/2018 to 4/2021. Patients were identified through a match case search of institutional records and inclusion was confirmed through manual chart review. Demographics, patient presentation, procedural data, and clinical outcomes were recorded in a password-encrypted database and compared between groups. Findings: Sixty-three patients underwent abscess drainage: 32 percutaneously and 31 surgically. In the PAD group, there was a 100% technical success rate and a 0% complication rate. In the SAD group, there was a 64.5% technical success rate and ten deaths within 30 days (32.3%), and one additional complication requiring major therapy (3.2%) (p < 0.001). Conclusion: Results from this study demonstrate that PAD can be performed with high technical success and without complication by trained IR physicians in Tanzania. The development of a successful PAD program exemplifies the drastic need to support the growth of IR services in this setting

"In the interests of justice?" The International Criminal Court, peace talks and the failed quest for war crimes accountability in northern Uganda

This article analyzes the first peace talks to take place against the backdrop of an International Criminal Court (ICC) investigation: the Juba Talks between the Lord’s Resistance Army and the Government of Uganda (2006–2008). Drawing on field research and original source material, it departs from well-worn peace versus justice debates and provides new empirical material to explore how the presence of the court shaped domestic political dynamics at Juba. It argues that at the level of broad rhetoric, the presence of the court created significant discord between negotiating parties. On a practical level, however, it created space for consensus, but not the type envisaged by international justice promoters. The court came to be seen by both sides as an intervention that needed to be contained and controlled. This resulted in the politically expedient Agreement on Accountability and Reconciliation, which showcased a transitional justice “tool-kit,” but was based on a shared desire to evade the jurisdiction of international criminal justice. Given its practical complexity, the transitional justice agreement was ultimately rejected by Joseph Kony, who became increasingly distrustful of his own negotiating team at Juba. In findings relevant to other contexts, the article presents in-depth analyses of how domestic political dynamics around the ICC intervention produced a national transitional justice framework designed to protect both parties from war crimes accountability

Causal Modeling Using Network Ensemble Simulations of Genetic and Gene Expression Data Predicts Genes Involved in Rheumatoid Arthritis

Tumor necrosis factor α (TNF-α) is a key regulator of inflammation and rheumatoid arthritis (RA). TNF-α blocker therapies can be very effective for a substantial number of patients, but fail to work in one third of patients who show no or minimal response. It is therefore necessary to discover new molecular intervention points involved in TNF-α blocker treatment of rheumatoid arthritis patients. We describe a data analysis strategy for predicting gene expression measures that are critical for rheumatoid arthritis using a combination of comprehensive genotyping, whole blood gene expression profiles and the component clinical measures of the arthritis Disease Activity Score 28 (DAS28) score. Two separate network ensembles, each comprised of 1024 networks, were built from molecular measures from subjects before and 14 weeks after treatment with TNF-α blocker. The network ensemble built from pre-treated data captures TNF-α dependent mechanistic information, while the ensemble built from data collected under TNF-α blocker treatment captures TNF-α independent mechanisms. In silico simulations of targeted, personalized perturbations of gene expression measures from both network ensembles identify transcripts in three broad categories. Firstly, 22 transcripts are identified to have new roles in modulating the DAS28 score; secondly, there are 6 transcripts that could be alternative targets to TNF-α blocker therapies, including CD86 - a component of the signaling axis targeted by Abatacept (CTLA4-Ig), and finally, 59 transcripts that are predicted to modulate the count of tender or swollen joints but not sufficiently enough to have a significant impact on DAS28

Cytokine-associated neutrophil extracellular traps and antinuclear antibodies in Plasmodium falciparum infected children under six years of age

<p>Abstract</p> <p>Background</p> <p>In <it>Plasmodium falciparum</it>-infected children, the relationships between blood cell histopathology, blood plasma components, development of immunocompetence and disease severity remain poorly understood. Blood from Nigerian children with uncomplicated malaria was analysed to gain insight into these relationships. This investigation presents evidence for circulating neutrophil extracellular traps (NETs) and antinuclear IgG antibodies (ANA). The presence of NETs and ANA to double-stranded DNA along with the cytokine profiles found suggests autoimmune mechanisms that could produce pathogenesis in children, but immunoprotection in adults.</p> <p>Methods</p> <p>Peripheral blood smear slides and blood samples obtained from 21 Nigerian children under six years of age, presenting with uncomplicated malaria before and seven days after initiation of sulphadoxine-pyrimethamine (SP) treatment were analysed. The slides were stained with Giemsa and with DAPI. Levels of the pro-inflammatory cytokines IFN-γ, IL-2, TNF, CRP, and IL-6, select anti-inflammatory cytokines TGF-β and IL-10, and ANA were determined by immunoassay.</p> <p>Results</p> <p>The children exhibited circulating NETs with adherent parasites and erythrocytes, elevated ANA levels, a Th2 dominated cytokine profile, and left-shifted leukocyte differential counts. Nonspecific ANA levels were significant in 86% of the children pretreatment and in 100% of the children seven days after SP treatment, but in only 33% of age-matched control samples collected during the season of low parasite transmission. Levels of ANA specific for dsDNA were significant in 81% of the children both pre-treatment and post treatment.</p> <p>Conclusion</p> <p>The results of this investigation suggest that NET formation and ANA to dsDNA may induce pathology in falciparum-infected children, but activate a protective mechanism against falciparum malaria in adults. The significance of in vivo circulating chromatin in NETs and dsDNA ANA as a causative factor in the hyporesponsiveness of CpG oligonucleotide-based malaria vaccines is discussed.</p