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The evolution of next-generation communication systems demands that wireless networks possess the attributes of awareness, adaptability, and intelligence. Wireless sensing techniques provide valuable information about the radio signals in the environment. However, hostile threats, such as jamming, eavesdropping, and manipulation, pose significant challenges to these networks. This article presents a comprehensive study of an innovative RF-jamming detection testbed designed to combat these threats. The testbed leverages the spectral scan capability of the wireless network interfaces and the jamming toolkit, JamRF, to accurately detect and mitigate jamming attacks. This study outlines the methodology used to develop the testbed, along with a detailed discussion on the rationales behind the design decisions. The accompanying RF jamming dataset, which comprises experimentally measured data, is expected to promote the development and evaluation of jamming detection and avoidance systems. As a proof-of-concept, we trained five different machine learning algorithms and achieved a jamming detection accuracy of over 90% for all algorithms. The proposed RF jamming dataset and testbed represent a significant advancement in the fight against malicious interference in wireless networks.

Despite the rich information about the physiological state of a cell encoded in the dynamic changes of cell-surface glycans, chemical methods to capture specific glycan epitopes at the single-cell level are quite limited. Here, we report a chemoenzymatic method for the single-cell detection of N-acetyllactosamine (LacNAc) by labeling LacNAc with a specific DNA barcode. The chemoenzymatic labeling does not alter the transcriptional status of immune cells and is compatible with multiple scRNA-seq platforms. Integrated analysis of LacNAc and the transcriptome of T cells at the single-cell level reveals that the amount of cell-surface LacNAc is significantly upregulated in activated CD8+T cells but maintained at basal levels in resting CD8+T cells (i.e., naive and central memory T cells). Further analysis confirms that LacNAc levels are positively correlated with the glycolytic activity of CD8+T cells during differentiation. Taken together, our study demonstrates the feasibility of the chemoenzymatic detection of cell-surface glycan in single-cell RNA sequencing-based multiomics with TCR sequence and cell-surface epitope information (i.e., scTCR and CITE-seq), and provides a new way to characterize the biological role of glycan in diverse physiological states.

Nowadays, the global navigation satellite system (GNSS) positioning techniques based on the International GNSS Service (IGS) products are extensively used for various precise applications. However, specific conditions such as the dual-frequency observations and the final IGS products are required. Consequently, the absence of the final IGS data and using single-frequency observations will degrade these techniques’ accuracy. In this paper, two algorithms through two separated stages are formulated for improving the single-frequency GNSS observations by using one GNSS receiver based on the broadcast ephemerides in real time or close to real time. The first algorithm represents the preparation stage for the second one. It classifies the observations by separating the optimal values of position dilution of precision (PDOP) and the number of satellites (NOS), as well as the corresponding values of coordinates. The second stage includes an algorithm based on the artificial neural network (ANN) approach, which is set at the ANN variables that produce the best precision through the applied tests at the present study. Binary numbers, log sigmoid-Purelin, cascade forward net, and one hidden layer with a size of 10 neurons are the optimal variables of ANN inputs format, transfer functions constellations, feedforward net type, and the number of hidden layers (NHL) and its size, respectively. The simulation results show that the designed algorithms produce a significant improvement in the horizontal and vertical components. Lastly, an evaluation stage is performed in the case of dual-frequency observations by using broadcast ephemerides. The simulation outputs indicate that the precision at applying the proposed integration is completely enhanced compared with the outputs of IGS final data.

AbstractThe present study focused on the development of a simple, reliable, cost-effective, precise, and stable quality by design (QbD) RP-HPLC method for estimation of Abiraterone Acetate in bulk, pharmaceutical dosage form, and in-house-developed nano-formulation. The essential analytical target profile (ATP), and critical analytical attributes (CAAs) were described. Plackett-Burman Design and Box-Behnken Design were used for screening and optimization of critical method parameters (CMPs). The chromatographic method with reverse-phase isocratic mode, C-18 column, 69: 31 (% v/v) acetonitrile, and ammonium acetate buffer (pH 3.5) as a mobile phase with a flow rate of 0.75 ml/min and 235 nm detection wavelength was developed. The method was validated as per International Conference on Harmonization guideline and found to be linear between 10 to 180 μg/ml with R2 0.997, detection limit of 3.64 μg/ml, and quantitation limit of 11.05 μg/ml. Precision was demonstrated using a relative standard deviation of 1.55 % and 1.59 % for inter and intraday studies respectively. The developed method was also used for the analysis of ABT in bulk, tablet dosage form, and in-house-developed nanosponges prepared using different cross-linking agents, devoid of any interference of formulation excipients. The method effectively established the utility of QbD for optimizing chromatographic conditions used for the estimation of Abiraterone acetate.

ABSTRACTThis study engaged health professionals in in-depth, semi-structured interviews to explore their opinions concerning the issues surrounding vaccine hesitancy in Malaysia and strategies to improve vaccination to stamp the rise of vaccine preventable diseases (VPDs). Opinions on how to address the resurgence of VPDs in the era of increasing vaccine hesitancy were obtained. Eight health professionals, including geriatricians, pediatricians, microbiologists, public health specialists, and family medicine specialists were interviewed. The influence of anti-vaccination propaganda, past-experience of adverse event following immunization (AEFI), perceived religious prohibition, a belief that traditional complementary and alternative medicine (TCAM) use is safer, pseudoscience beliefs, and anti-vaccine conspiracy theories were identified as reasons for refusing to vaccinate. The interplay of social, cultural and religious perspectives in influencing perceived religious prohibition, pseudoscience beliefs, and the use of TCAM contributing to vaccine refusal was found. Five broad themes emerged from the health professionals regarding strategies to address vaccine hesitancy, including establishing an electronic vaccination registry, increasing public awareness initiatives, providing feedback to the public on the findings of AEFI, training of front-line healthcare providers, and banning the dissemination of anti-vaccine information via social media. With regards to identifying strategies to address the resurgence of VPDs, mandatory vaccination received mixed opinions; many viewed supplementary immunization activity and the prevention of travel and migration of unvaccinated individuals as being necessary. In conclusion, the present study identified unique local cultural, traditional and religious beliefs that could contribute to vaccine hesitancy in addition to issues surrounding vaccination refusal similarly faced by other countries around the world. This information are important for the formulation of targeted intervention strategies to stamp vaccine hesitancy in Malaysia which are also a useful guide for other countries especially in the Southeast Asia region facing similar vaccine hesitancy issues.

Agricultural produce upon harvesting have high moisture content which makes it unsafe for storage as the moisture in the crops attracts microorganisms which result in deterioration of the products. A solar dryer was developed, simulated and tested under the weather conditions of Zaria, Nigeria. TRANSYS 16.0 software was used to simulate the collectors’ outlet air temperature. A MATLAB code was written to compute the weight losses of yam slices present in a drying chamber. The computed Nash-Sutcliffe Coefficient of Efficiency values and its corresponding root means square errors between the modelled collector air temperature, and the experimental collector air temperatures confirm the validity of TRANSYS 16 model owing to the good quality of fit between the experimental and the simulated results. Similarly, the computed Nash-Sutcliffe Coefficient of Efficiency values and its corresponding root means square errors between the modelled weight loss of yam slices, and the observed weight loss of yam slices follows the same trend.

Abstract: The Global Positioning System (GPS) permanent stations at the equatorial and southern sub-tropical hydrobelts of South America undergo the highest seasonality on the Earth due to hydrological loadings. Fortunately, there are products that account for such variations, although some of them have not been properly evaluated. For instance, global solutions of Gravity Recovery and Climate Experiment (GRACE) are band-limited to lower frequencies; therefore, comparisons with GPS data must account for such spectral inconsistencies. It is proposed to spatially average 39 GPS sites by applying Gaussian smoothing, which allows comparisons with long-wavelength part of GRACE solutions by Center for Space Research (CSR), GeoForschungszentrum, and Jet Propulsion Laboratory. Comparisons are also carried out with loadings from Noah-driven Global Land Data Assimilation System (GLDAS) and GRACE mass concentration (mascon) solution by Goddard Space Flight Center. Results show that CSR best reduces the variances of the radial displacements considering both spatially filtered (70%) and unfiltered (53%) GPS data covering the period from Jan 2010 to Dec 2015. However, GLDAS-Noah underestimates the amplitudes of vertical loadings, which might be due to unmodeled inland water and groundwater storages. While acknowledging that a denser distribution of GPS stations is needed, the findings still shed light on the quality of the global hydrological loading products based on GRACE and GLDAS datasets, which might be of interest to the respective science teams. Graphic abstract:

Purpose: The purpose of this paper is to present the findings of a theoretical calculation for the emergency evacuation of an auditorium facility managed by a university in Saudi Arabia. Design/methodology/approach: The authors reviewed the published literature to identify the sources of fire incidence, guidelines for means of escape in assembly occupancies and human behavior in fire emergencies. The theoretical method of the SFPE handbook to estimate the required evacuation time was subsequently applied to a case study of an auditorium facility managed by a university located in Saudi Arabia. Finally, the authors developed recommendations for the performance-based fire safety evacuation of the auditorium facility under review. Findings: The study showed that a total of 6 minutes 39 seconds is needed to evacuate the whole auditorium. However, reviewed literature for assembly occupancies requires between 4 minutes 30 seconds and 6 minutes 24 seconds for total evacuation. Though, the calculated evacuation time is close to generally acceptable limits. It was noted that overcrowding and bottlenecks may be formed in some of the exit routes. Originality/value: This paper will stimulate and increase research and industry concern for performance-based design of assembly-type facilities. This will be of significant value to designers, engineers, facilities managers, and owners in ensuring the safety of occupants in assembly-type facilities.

Image retrieval is an important research area, where a variety of clustering techniques have been introduced in the literature to categorise and group the image resources according to their characteristics. In this paper, we provide a brief survey of supervised and unsupervised clustering methods that have been patented up to date in accordance with their applications in image retrieval. In particular, we focus on introducing the concepts generated within these patents based on the limitations found in the classical image retrieval systems. Finally, a summary is made and future work in image retrieval is outlined.

The antibiotic susceptibility profiles and the repetitive extragenic palindromic sequence-based polymerase chain reaction (REP-PCR)-determined genotypes of 109 Acinetobacterstrains collected from the University Malaya Medical Center (UMMC), Kuala Lumpur, Malaysia, in 1987 (N=21) and 1996–1998 (N=88) were established. Twelve antibiotic susceptibility profiles of antibiotics used at the UMMC were obtained. In descending order of effectiveness, imipenem, amikacin and ciprofloxacin were the most effective against the Acinetobacterstrains. Compared with 1987 isolates, the isolates obtained in 1996–1998 had decreased susceptibility to these antibiotics and were tolerant to the antibiotics up to an MIC90of ≥256mg/L. REP-PCR DNA fingerprints of all the isolates revealed the presence of four Acinetobacterspp. lineages; 92% of all the isolates belonged to two dominant lineages (genotypes 1 and 4). Genotype 4 isolates predominant in 1987 showed increased resistance and antibiotic tolerance to imipenem, amikacin and ciprofloxacin compared with the 1996–1998 isolates. In contrast, genotype 1 isolates from 1996–1998 were mainly sensitive to these antibiotics. These findings demonstrate the presence of at least two independent Acinetobacterspp. lineages in the same hospital, and suggest the possibility that genotype 4 Acinetobacterspp. acquired the resistance phenotype in situ, whereas most of the genotype 1 isolates were probably introduced to the hospital in recent years.

The reactions of fluorobenzene, 3-fluorotoluene, and three isomers of difluorotoluene, chlorobenzene, and bromobenzene with excesses of methanol were investigated on the large-pore catalysts HBeta (*BEA) and HSAPO-5 (AFI), and on the medium-pore HZSM-5 (MFI). Flow reactor studies in pulse mode with GC−MS detection revealed that the fluorobenzene derivatives were readily methylated at, for example, 375 °C, but not even pentamethylfluorobenzene was obviously active as a reaction center for methanol-to-olefin (MTO) catalysis. Carbon-labeling studies revealed that small amounts of methylbenzenes were formed by defluorination, and these aromatic hydrocarbons seemed to account for the small yields of olefins (and their secondary reaction products) observed. Loss of one fluorine was also evident in the products for one of the difluorotoluene isomers. On HSAPO-5 the activity order for ring-methylation of halobenzenes was F > Cl ≫ Br. On HZSM-5, chlorobenzene and especially bromobenzene lost halogen through a route forming halomethane. These largely negative results will nevertheless be useful in testing theoretical models of the detailed reaction steps in the hydrocarbon pool mechanism for MTO catalysis.

Summary Exposure of human lung fibroblasts to human cytomegalovirus (HCMV) stimulated a rapid increase in the release of [3H] from cells prelabelled with radiolabelled arachidonic acid ([3H]AA). Maximum stimulation of [3H] release was observed at 20 min postinfection and was quantitatively similar to that induced by the tumor promoter 12-O-tetradecanoylphorbol 13-acetate (TPA: 10nM) or fetal calf serum (5%). The level of [3H] release was dependent on the multiplicity of infection, and appeared to be mediated by a component(s) of the virion, since the findings from three series of experiments suggested that neither infectious virus, nor HCMV-specific macromolecular synthesis was required for stimulation of [3H] release. (1) Inactivation of HCMV infectivity with ultra-violet (UV) light (~254nm, 4.80 × 104 ergs/mm2) did not diminish the stimulation of [3H] release. (2) Significant reduction in the level of [3H] release was not observed when infected cells were maintained in the presence of a protein synthesis inhibitor, cycloheximide (50 µg/ml), or an inhibitor of mRNA synthesis, 3'-deoxyadenosine (cordycepin, 50 µg/ml). (3) No correlation was established between the expression of HCMV immediate early (IE) antigens and the induction of [3H] release, since there was little, if any, synthesis of HCMV IE antigen detectable by anticomplement immunofluorescence through the first 30 min postinfection. These findings suggesting that the HCMV particle rapidly stimulates AA metabolism are consistent with the view that the interaction of a HCMV virion component(s) with the cell surface may initiate membrane-associated events similar to those induced by growth factors.

Summary The contribution of expression of human cytomegalovirus (HCMV) immediate early (IE) genes to the rapid and transient increase in cellular (c)-oncogene (fos, jun, myc) transcription following HCMV infection was investigated. A partial temporal overlap was observed between the increases in c-oncogene RNA levels and the increase in either transcripts from HCMV IE genes or the number of cells in which HCMV IE proteins were detected. The increases in c-oncogene RNA levels, however, slightly preceded the increase in the detection of HCMV IE transcripts or proteins. To distinguish between the temporal coincidence and a direct relationship between expression of HCMV IE genes and the increased transcription of c-oncogenes, the number of cells synthesizing HCMV IE proteins was reduced by infecting with virus stock enriched in defective particles. Alternatively, the synthesis of HCMV IE proteins was essentially eliminated by ultra-violet (UV) irradiation of virus stock or by inhibitors of protein synthesis. Virus stocks enriched in defective particles demonstrated a substantially reduced capacity to direct the synthesis of HCMV IE proteins, but were more efficient in activating c-oncogene expression than infectious virus stocks. Elimination of expression of HCMV IE genes by UV-irradiation of virus stock or by inhibiting de novo viral and/or cellular protein synthesis with cycloheximide (100 µg/ml) or anisomycin (100 µg/ml) did not eliminate the HCMV-induced increase in RNA levels of c-oncogenes. These data indicate that activation of these early response cellular genes is independent from de novo expression of HCMV IE proteins, and possibly involves biologically active virion proteins that are related to the induction of a cascade of cellular events associated with the binding of HCMV to its cellular receptor.

During an outbreak of hand-foot-mouth disease caused by enterovirus 71 (EV-71) in 1997, 4 children presented with sudden cardiopulmonary collapse and minimal neurologic features. All children received cardiopulmonary resuscitation but died within a few hours of admission. Postmortem studies showed infection by EV-71 with extensive damage to the medulla and pons. We postulate an etiologic link between EV-71 and brainstem encephalomyelitis as the cause of pulmonary edema and death. (J Pediatr 1998;133:795-8)

The heat shock protein (HSP) response of Salmonella typhi following exposure to elevated growth temperatures was studied. Three major proteins with molecular sizes of 58, 68, and 88 kDa were abundantly expressed when S. typhi cells were shifted from 37 to 45 degrees C and to 55 degrees C. These proteins were also constitutively expressed at 37 degrees C. Western blotting and immunoprecipitation studies with anti-HSP monoclonal antibodies revealed that the 58- and 68-kDa proteins were analogous to the GroEL and DnaK proteins, respectively, of Escherichia coli. These HSPs are also abundantly present in the outer membrane fraction of disrupted cells and, to a lesser extent, in the cytosol. Immunoblotting experiments with sera from patients with a culture-positive diagnosis of typhoid fever showed the presence of antibodies to these HSPs. Nine of twelve sera reacted with the 58-, 68-, and 88-kDa proteins, while three sera reacted only with the 68- and 88-kDa proteins. All 10 sera from healthy individuals showed no binding to these HSPs. In light of the well-documented roles of HSPs in the pathogenesis of microbial infections and as immunodominant antigens, these findings may be relevant for a better understanding of disease processes and for the future development of diagnostic and preventive strategies.

The mechanisms responsible for the human cytomegalovirus (HCMV)-induced increase in cellular oncogene RNAs for c-jun, c-fos, and c-myc in human embryo lung cells (I. Boldogh, S. AbuBakar, and T. Albrecht, Science 247:561-564, 1990) were investigated. Results of transcription assays indicated that the rapid increase in RNA levels for the above-noted oncogenes was controlled at the transcriptional level and was related to enhanced transcription. The maximum rates of transcription for c-jun and c-fos genes occurred at 40 min postinfection, while for the c-myc gene the maximum rate occurred at about 60 min. The magnitude of HCMV-induced activation of these cellular genes was similar to the activation induced by serum. The half-lives of the cellular oncogenes showed similar decay rates after either serum or HCMV activation when measured by dactinomycin chase. The half-life for c-fos or c-jun was about 20 min, and that for c-myc was about 40 min. Furthermore, inhibition of the RNA increase by dactinomycin or by alpha-amanitin suggested that the increase in RNA levels was due to an increase in the transcriptional activity of oncogenes triggered by HCMV.

The heat shock protein (HSP) response of Salmonella typhi following exposure to elevated growth temperatures was studied. Three major proteins with molecular sizes of 58, 68, and 88 kDa were abundantly expressed when S. typhi cells were shifted from 37 to 45 degrees C and to 55 degrees C. These proteins were also constitutively expressed at 37 degrees C. Western blotting and immunoprecipitation studies with anti-HSP monoclonal antibodies revealed that the 58- and 68-kDa proteins were analogous to the GroEL and DnaK proteins, respectively, of Escherichia coli. These HSPs are also abundantly present in the outer membrane fraction of disrupted cells and, to a lesser extent, in the cytosol. Immunoblotting experiments with sera from patients with a culture-positive diagnosis of typhoid fever showed the presence of antibodies to these HSPs. Nine of twelve sera reacted with the 58-, 68-, and 88-kDa proteins, while three sera reacted only with the 68- and 88-kDa proteins. All 10 sera from healthy individuals showed no binding to these HSPs. In light of the well-documented roles of HSPs in the pathogenesis of microbial infections and as immunodominant antigens, these findings may be relevant for a better understanding of disease processes and for the future development of diagnostic and preventive strategies.

Introduction: Anti-snake venom (ASV) is the standard therapy for the management of snakebite envenoming (SBE). Therefore, the knowledge of ASV among healthcare practitioners (HCPs) is essential for achieving optimal clinical outcomes in snakebite management. This study aimed to assess knowledge of ASV among the HCPs in northern Nigeria.Methods: We conducted a cross-sectional study involving eligible HCPs from different healthcare settings in northern Nigeria. The participants were recruited into the study using a combination of online (via Google Form) and face-to-face paper-based survey methods. The ASV knowledge of the respondents was measured using a validated anti-snake venom knowledge assessment tool (AKAT). Inadequate overall knowledge of ASV was defined as scores of 0–69.9%, and 70–100% were considered adequate overall knowledge scores. The predictors of ASV knowledge were determined using multiple logistic regression.Results: Three hundred and thirty-one (331) eligible HCPs were included in the study analysis (310 from online and 21 from paper-based survey). Overall, an estimated 12.7% of the participants had adequate knowledge of ASV. Adequate ASV knowledge was higher among physicians compared with other HCPs (21.7%; χ2= 8.1; p= 0.04). Those without previous training on ASV (adjusted odds ratio [aOR], 0.37; 95% confidence interval [CI], 0.18–0.73; p= 0.004) and who have not previously administered/dispensed ASV (aOR, 0.31; 95% CI, 0.15–0.63; p< 0.001) were less likely to have adequate knowledge of ASV.Conclusion: The knowledge of ASV among healthcare practitioners in northern Nigeria is grossly inadequate. Experience with administering or dispensing ASV predicts ASV knowledge. Therefore, appropriate interventions are needed to improve ASV knowledge, particularly among the HCPs, for optimal healthcare outcomes.

The increasing prevalence and miniaturization of electronic devices have driven global efforts to develop small-scale, self-sustaining, rugged, and ecologically viable power sources. Nanogenerators, with the ability to scavenge ambient energy from the environment, offer an elegant solution to this need for small-scale power sources. A major route of development for nanogenerators has been in integration with other green energy sources. This article discusses one such integrated power source, namely the photovoltaic and nanogenerator hybrid cells. These hybrid cells have come a long way in terms of mechanical integrity, power output, and efficiency since they were first reported in 2009. Each published instance of photovoltaic and nanogenerator hybrid cell is reviewed systematically and the salient points in each case have been discussed. The article has been concluded with a discussion on the current state of this technology, its limitations, and the avenues for future research.

Removal of heavy metal content in wastewater has been largely done by various methods. One effective and efficient method is the adsorption method. This study aims to reduce manganese (II) content in wastewater based on column adsorption method using absorbent material from bagasse. The fixed variable consisted of 50 g adsorbent, 10 liter adsorbate volume, flow rate of 7 liters / min. Independent variable of particle size with variation 10 - 30 mesh and contact time with variation 0 - 240 min and respon variable concentration of adsorbate (ppm), pH and conductivity. The results showed that the adsorption process of manganese metal is influenced by particle size and contact time. The adsorption kinetics takes place according to pseudo-second order kinetics with an equilibrium adsorption capacity (qe: mg / g) for 10 mesh adsorbent particles: 0.8947; 20 mesh adsorbent particles: 0.4332 and 30 mesh adsorbent particles: 1.0161, respectively. Highest removal efficience for 10 mesh adsorbent particles: 49.22% on contact time 60 min; 20 mesh adsorbent particles: 35,25% on contact time 180 min and particle 30 mesh adsorbent particles: 51,95% on contact time 150 min.

The viability of soyabean seeds, as affected by levels of field-applied nitrogen, phosphorus and potassium, seed storage methods and length of storage periods, was evaluated in two field experiments and twoseries of pot experiments. Seed viability was not significantly influenced by levels of field-applied nitrogen and potassium but it decreased with increasing levels of field-applied phosphorus. Soyabean seeds maintained relatively higher viability for the first 5 to 6 monthsafter harvesting, irrespective of storage method, but viability decreased with time thereafter, the rate of decline depending on storage method. Seeds stored at the relatively low temperatures of -5 deg. C and 10 deg. C, as in the deep freezer and refrigerator (respectively), maintained higher viability for longer periods of time than those stored in jute bags and airtight plastic containers kept in open stores at room temperature. [ABSTRACT FROM AUTHOR]