152 results on '"Ahmed, Asif"'
Search Results
2. Expanding the genetic spectrum of hereditary motor sensory neuropathies in Pakistan.
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Ahmed, Asif Naveed, Rawlins, Lettie E., Khan, Niamat, Jan, Zakir, Ubeyratna, Nishanka, Voutsina, Nikol, Azeem, Arfa, Khan, Saadullah, Baple, Emma L., Crosby, Andrew H., and Saleha, Shamim
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MEDICAL genetics ,MEDICAL genomics ,MOTOR neuron diseases ,GENETIC counseling ,CEREBELLAR ataxia - Abstract
Background: Hereditary motor and sensory neuropathy (HMSN) refers to a group of inherited progressive peripheral neuropathies characterized by reduced nerve conduction velocity with chronic segmental demyelination and/or axonal degeneration. HMSN is highly clinically and genetically heterogeneous with multiple inheritance patterns and phenotypic overlap with other inherited neuropathies and neurodegenerative diseases. Due to this high complexity and genetic heterogeneity, this study aimed to elucidate the genetic causes of HMSN in Pakistani families using Whole Exome Sequencing (WES) for variant identification and Sanger sequencing for validation and segregation analysis, facilitating accurate clinical diagnosis. Methods: Families from Khyber Pakhtunkhwa with at least two members showing HMSN symptoms, who had not previously undergone genetic analysis, were included. Referrals for genetic investigations were based on clinical features suggestive of HMSN by local neurologists. WES was performed on affected individuals from each family, with Sanger sequencing used to validate and analyze the segregation of identified variants among family members. Clinical data including age of onset were assessed for variability among affected individuals, and the success rate of genetic diagnosis was compared with existing literature using proportional differences and Cohen's h. Results: WES identified homozygous pathogenic variants in GDAP1 (c.310 + 4 A > G, p.?), SETX (c.5948_5949del, p.(Asn1984Profs*30), IGHMBP2 (c.1591 C > A, p.(Pro531Thr) and NARS1 (c.1633 C > T, p.(Arg545Cys) as causative for HMSN in five out of nine families, consistent with an autosomal recessive inheritance pattern. Additionally, in families with HMSN, a SETX variant was found to cause cerebellar ataxia, while a NARS1 variant was linked to intellectual disability. Based on American College of Medical Genetics and Genomics criteria, the GDAP1 variant is classified as a variant of uncertain significance, while variants in SETX and IGHMBP2 are classified as pathogenic, and the NARS1 variant is classified as likely pathogenic. The age of onset ranged from 1 to 15 years (Mean = 5.13, SD = 3.61), and a genetic diagnosis was achieved in 55.56% of families with HMSN, with small effect sizes compared to previous studies. Conclusions: This study expands the molecular genetic spectrum of HMSN and HMSN plus type neuropathies in Pakistan and facilitates accurate diagnosis, genetic counseling, and clinical management for affected families. [ABSTRACT FROM AUTHOR]
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- 2024
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3. Effects of Ultrasound-Assisted Extraction on Physicochemical and Functional Properties of Gelatin Derived from Hilsha (Tenualosa ilisha) Scales.
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Refat, Md Kamrul Hasan, Nishi, Farzana Ahmed, Shubhro, Kumar, Anisuzzaman, Md, Ahmed, Asif, Islam, Md Emdadul, Islam, Md Nazrul, Islam, Kazi Mohammed Didarul, and Billah, Md Morsaline
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Gelatin is a multifunctional protein with numerous applications in the food and pharmaceutical industries. The increased global demand for gelatin and issues regarding mammalian collagen have prompted an imperative urge for alternative sources. Therefore, this study aimed to explore the impact of ultrasound-assisted extraction on the physicochemical, functional, and bioactive attributes of gelatin obtained from Tenualosa ilisha scales. Ultrasound-assisted gelatin (UAG) extraction substantially increased the yield (34.49%), reducing fat and moisture content compared to water bath gelatin (WBG) extraction (20.06%). Sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE) revealed α1, α2, and β chains, corroborating a triple helical conformation with UAG displaying shorter peptide composition. Fourier-transform infrared spectroscopy (FT-IR) showcased distinct peaks for amide- I, II, III, and A with decreased molecular order owing to ultrasound treatment. The WBG exhibited a lower UV-transmittance and a higher gel melting temperature, whereby, UAG displayed an excellent foaming capacity and stability with improved performance at higher concentrations. The WBG demonstrated superior emulsion activity and stability index, however, the emulsion activity of both gelatins declined with increasing concentrations. The gelatins showed a similar water-holding capacity, although WBG possessed a greater fat-binding capacity compared to UAG. However, UAG demonstrated enhanced antioxidant effects, revealing an IC
50 of 121.17 ± 2.38 for scavenging free radicals and an EC50 of 184.48 ± 3.16 for reducing Fe3+ , thus, minimizing oxidative stress. The findings will offer novel insights into the influence of ultrasound treatment on the properties of fish scale gelatin and developing methods for tailoring scale gelatin for food and pharmaceutical interventions. [ABSTRACT FROM AUTHOR]- Published
- 2025
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4. Investigating the genetic basis of hereditary spastic paraplegia and cerebellar Ataxia in Pakistani families.
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Azeem, Arfa, Ahmed, Asif Naveed, Khan, Niamat, Voutsina, Nikol, Ullah, Irfan, Ubeyratna, Nishanka, Yasin, Muhammad, Baple, Emma L., Crosby, Andrew H., Rawlins, Lettie E., and Saleha, Shamim
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RESOURCE-limited settings ,PAKISTANIS ,CEREBELLAR ataxia ,GENETIC counseling ,NEURODEGENERATION ,FAMILIAL spastic paraplegia - Abstract
Background: Hereditary Spastic Paraplegias (HSPs) and Hereditary Cerebellar Ataxias (HCAs) are progressive neurodegenerative disorders encompassing a spectrum of neurogenetic conditions with significant overlaps of clinical features. Spastic ataxias are a group of conditions that have features of both cerebellar ataxia and spasticity, and these conditions are frequently clinically challenging to distinguish. Accurate genetic diagnosis is crucial but challenging, particularly in resource-limited settings. This study aims to investigate the genetic basis of HSPs and HCAs in Pakistani families. Methods: Families from Khyber Pakhtunkhwa with at least two members showing HSP or HCA phenotypes, and who had not previously been analyzed genetically, were included. Families were referred for genetic analysis by local neurologists based on the proband's clinical features and signs of a potential genetic neurodegenerative disorder. Whole Exome Sequencing (WES) and Sanger sequencing were then used to identify and validate genetic variants, and to analyze variant segregation within families to determine inheritance patterns. The mean age of onset and standard deviation were calculated to assess variability among affected individuals, and the success rate was compared with literature reports using differences in proportions and Cohen's h. Results: Pathogenic variants associated with these conditions were identified in five of eight families, segregating according to autosomal recessive inheritance. These variants included previously reported SACS c.2182 C > T, p.(Arg728*), FA2H c.159_176del, p.(Arg53_Ile58del) and SPG11 c.2146 C > T, p.(Gln716*) variants, and two previously unreported variants in SACS c.2229del, p.(Phe743Leufs*8) and ZFYVE26 c.1926_1941del, p.(Tyr643Metfs*2). Additionally, FA2H and SPG11 variants were found to have recurrent occurrences, suggesting a potential founder effect within the Pakistani population. Onset age among affected individuals ranged from 1 to 14 years (M = 6.23, SD = 3.96). The diagnostic success rate was 62.5%, with moderate effect sizes compared to previous studies. Conclusions: The findings of this study expand the genotypic and phenotypic spectrum of HSPs and HCAs in Pakistan and emphasize the importance of utilizing exome/genome sequencing for accurate diagnosis or support accurate differential diagnosis. This approach can improve genetic counseling and clinical management, addressing the challenges of diagnosing neurodegenerative disorders in resource-limited settings. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Enhancing Deep Line Segment Detection and Performance Evaluation for Wood: A Deep Learning Approach with Experiment-Based, Domain-Specific Implementations.
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Luo, Jing, Guo, Yufan, Liu, Zhen, Hu, Qicheng, Hoque, Md Ahatasamul, and Ahmed, Asif
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DAMAGE models ,CYCLIC loads ,DEEP learning ,MACHINE learning ,EVALUATION methodology ,WOODEN beams - Abstract
In recent decades, wood structures have gained significant attention for their ecological benefits and architectural versatility. The performance of wood, a popular construction material, often depends on the integrity of its connections. This study focuses on bolted glulam timber connections, which are strong but prone to cracks that pose structural health challenges. Traditional crack evaluation methods are manual, time-consuming, and error-prone. To address these issues, this research proposes a two-stage performance evaluation method. In the first stage, an innovative approach called 'Enhanced Deep Line Segment Detection' (Deep LSD), a non-supervised machine learning technique, is used for crack detection without relying on large, annotated datasets, thus enhancing efficiency and adaptability. In the second stage, cyclic loading assays simulate varying damage stages to collect data and establish a correlation between crack states and connection damage. The Park and Ang damage model is employed within this framework to assess the extent of damage. The efficacy of enhanced deep LSD is confirmed by comparing detected crack areas with ground truth measurements, yielding a high R-squared value of 0.98 and a minimal error margin of 1.41. Additionally, a damage index based on the Chinese standard (GB/T 24335-2009) is used to classify damage across different connection groups, ensuring robustness and alignment with established practices. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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6. Application of Electrical Resistivity Tomography in Geotechnical and Geoenvironmental Engineering Aspect.
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Alam, Md Jobair Bin, Ahmed, Asif, and Alam, Md Zahangir
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GEOTECHNICAL engineering ,ENVIRONMENTAL geotechnology ,ELECTRICAL resistivity ,GEOPHYSICS ,EVAPOTRANSPIRATION - Abstract
Electrical resistivity tomography (ERT) has turned out to be one of the most applied and user-friendly geophysical methods in geotechnical and geoenvironmental research. ERT is an emerging technology that is becoming popular nowadays for investigating subsurface conditions. Multiple attributes of the technology using various electrode configurations significantly reduce measurement time and are suitable for applications even in hardly accessible mountain areas. It is a noninvasive test for subsurface characterization and a very sensitive method used to determine geophysical properties, i.e., structural integrity, water content, fluid composition, etc. This paper aimed to elucidate the ERT technique's main features and applications in geotechnical and geoenvironmental engineering through four case studies. The first case study investigated the possible flow paths and areas of moisture accumulation after leachate recirculation in a bioreactor landfill. The second case study attempted to determine the moisture variation along highway pavement. The third case study explored the slope failure investigation by ERT. The fourth case study demonstrated the efficiency of the ERT method in the landfill evapotranspiration (ET) cover to investigate moisture variation on a broader scale and performance monitoring. In all of the four cases, ERT exhibited promising performance. [ABSTRACT FROM AUTHOR]
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- 2024
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7. Genetic heterogeneity in epilepsy and comorbidities: insights from Pakistani families.
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Yasin, Muhammad, Licchetta, Laura, Khan, Niamat, Ullah, Irfan, Jan, Zakir, Dawood, Muhammad, Ahmed, Asif Naveed, Azeem, Arfa, Minardi, Raffaella, Carelli, Valerio, and Saleha, Shamim
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EPILEPSY ,PAKISTANIS ,SLEEP interruptions ,MISSENSE mutation ,PEOPLE with epilepsy - Abstract
Background: Epilepsy, a challenging neurological condition, is often present with comorbidities that significantly impact diagnosis and management. In the Pakistani population, where financial limitations and geographical challenges hinder access to advanced diagnostic methods, understanding the genetic underpinnings of epilepsy and its associated conditions becomes crucial. Methods: This study investigated four distinct Pakistani families, each presenting with epilepsy and a spectrum of comorbidities, using a combination of whole exome sequencing (WES) and Sanger sequencing. The epileptic patients were prescribed multiple antiseizure medications (ASMs), yet their seizures persist, indicating the challenging nature of ASM-resistant epilepsy. Results: Identified genetic variants contributed to a diverse range of clinical phenotypes. In the family 1, which presented with epilepsy, developmental delay (DD), sleep disturbance, and aggressive behavior, a homozygous splice site variant, c.1339–6 C > T, in the COL18A1 gene was detected. The family 2 exhibited epilepsy, intellectual disability (ID), DD, and anxiety phenotypes, a homozygous missense variant, c.344T > A (p. Val115Glu), in the UFSP2 gene was identified. In family 3, which displayed epilepsy, ataxia, ID, DD, and speech impediment, a novel homozygous frameshift variant, c.1926_1941del (p. Tyr643MetfsX2), in the ZFYVE26 gene was found. Lastly, family 4 was presented with epilepsy, ID, DD, deafness, drooling, speech impediment, hypotonia, and a weak cry. A homozygous missense variant, c.1208 C > A (p. Ala403Glu), in the ATP13A2 gene was identified. Conclusion: This study highlights the genetic heterogeneity in ASM-resistant epilepsy and comorbidities among Pakistani families, emphasizing the importance of genotype-phenotype correlation and the necessity for expanded genetic testing in complex clinical cases. [ABSTRACT FROM AUTHOR]
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- 2024
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8. THERMOPHYSICAL PROPERTIES OF HYPOEUTECTIC, EUTECTIC AND HYPEREUTECTIC Al-Si AUTOMOTIVE ALLOYS UNDER AGEING TREATMENT.
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Razin, Ahmed Asif, Ahammed, Dewan Sal-Sabil, Khan, Akib Abdullah, and Kaiser, Mohammad Salim
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HYPEREUTECTIC alloys ,THERMOPHYSICAL properties ,HARDENING (Heat treatment) ,PRECIPITATION (Chemistry) ,ALLOYS ,SUPERSATURATED solutions - Abstract
Influence of different levels of silicon under a variety of thermal treatment is investigated on the thermophysical behaviour of Al-Si-Cu-Mg automotive alloys. Conventional cast alloys are subjected to T6 heat treatment for age hardening. Hardness values, thermal conductivity along with microstructural observation under different heattreated conditions are well thought-out to comprehend the ageing performance and the precipitation behaviour of the alloys. From these investigational results it is indicated that two successive hardening peaks take place in the aged alloys. Ageing sequence consists of different phases like a supersaturated solid solution, GP zones, intermediate β", intermetallic β', equilibrium β and the Q phase but GP zones and the metastable phases are most likely responsible for these ageing peaks. Thermal conductivity decreases for these precipitates formation during ageing and increases for relieving the internal stress, dissolution of metastable phase and coarsening the precipitation of the alloys. Adding up of Si to the alloy showed earlier ageing peaks with higher intensities intended for its increasing properties of heterogeneous nucleation and diffusion kinetics. After ageing around at 200°C for four hours the alloys offer the height hardness. Microstructural study reveals that eutectic silicon makes the grain boundary coarsen and beyond the eutectic composition the star-shaped blocky primary Si is formed. Subsequent to ageing at 350oC for one hour the alloys reach completely recrystallized state. [ABSTRACT FROM AUTHOR]
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- 2024
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9. PRISM III Score and hsCRP as Predictors of Mortality in Patients with Sepsis, Severe Sepsis, and Septic Shock.
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Ahmed, Asif, Ahmad, Qazi Iqbal, and Yousuf, Shahzada Saleem
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CHILD mortality ,SEPTIC shock ,INTENSIVE care units ,PEDIATRIC intensive care ,ARTIFICIAL respiration - Abstract
Background: Severe sepsis and septic shock are two major causes of death in children with sepsis. The Pediatric risk of mortality (PRISM) score allows for mortality risk assessment in the pediatric ICU. It is institution-independent and can be used within limits to compare different intensive care units. Materials and Methods: It was a prospective observational hospital based study. All patients admitted in the Paediatric Intensive Care Unit between the age group of one month to 14 years who fulfilled the inclusion criteria were prospectively observed and details were recorded in a predesigned proforma. Critical illness severity was estimated with the Paediatric Risk of Mortality (PRISM III-24) score. Results: 30 patients (14 males & 16 females) were included in the study&mortality rate of 40.0% was witnessed.29(96.7%) patients were given pressor support. In terms of outcome, 17(94.4%) of the 18 discharged patients received pressor support and 01(5.6%) of them did not receive any pressor support. On the other hand, all 12 expired patients received pressor support (P=0.406). 25(83.3%) patients required mechanical ventilation. In terms of outcome, 14(77.8%) of the discharged patients required mechanical ventilation while 04(22.2%) of them did not require it. On the other hand, out of 16 patients who expired, 11(91.7%) required mechanical ventilation while 01(8.3%) did not require it (P=0.317). None of the patients, either from the discharged ones or from the expired ones, had a low-risk HsCRP level(<3). The mean PRISM III Score at admission in discharged patients was 20.5±3.65 and the mean PRISM III Score at admission in expired patients was 23.25±1.76 (P=0.01). The mean PRISM III score at 24 hours in discharged patients was 17.33±4.46 and the mean PRISM III score in expired patients was 22.50±1.50 (P=0.001). When analyzed in specificity versus threshold (ROC) curve, PRISM III Score was significant at both time intervals i.e., at admission (P=0.019) and at 24 hours (P=0.003). Conclusion:. [ABSTRACT FROM AUTHOR]
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- 2024
10. Blood-brain barrier disruption and edema formation due to prolonged starvation in wild-type mice.
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Hossain, M. Ibrahim, Haque, Mehjabeen, Akter, Maria, Sharmin, Sabrina, and Ahmed, Asif
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VASCULAR endothelial growth factors ,TAU proteins ,VASCULAR endothelial growth factor receptors ,CARRIER proteins ,CEREBRAL edema - Abstract
INTRODUCTION: Different types of diseases have been treated by restricted caloric intake or fasting. Although during this long time, fasting protective measures, for example, supplements, are given to the patients to protect vital organs such as the liver and kidney, little attention is given to the brain. The current research aims to investigate hypoglycemia due to prolonged fasting disrupts blood-brain barrier (BBB) in mice. MATERIALS AND METHODS: Immunohistochemistry (IHC) and in situ hybridization (ISH) techniques were used to examine the expression of different genes. Evans blue extravasation and wet-dry technique were performed to evaluate the integrity of BBB and the formation of brain edema, respectively. RESULTS: We confirmed that hypoglycemia affected mice fasting brain by examining the increased expression of glucose transporter protein 1 and hyperphosphorylation of tau protein. We subsequently found downregulated expression of some genes, which are involved in maintaining BBB such as vascular endothelial growth factor (VEGF) in astrocytes and claudin-5 (a vital component of BBB) and VEGF receptor (VEGFR1) in endothelial cells by ISH. We also found that prolonged fasting caused the brain endothelial cells to express lipocalin-2, an inflammatory marker of brain endothelial cells. We performed Evans blue extravasation to show more dye was retained in the brain of fasted mice than in control mice as a result of BBB disruption. Finally, wet-dry method showed that the brain of prolonged fasted mice contained significantly higher amount of water confirming the formation of brain edema. Therefore, special attention should be given to the brain during treatment with prolonged fasting for various diseases. CONCLUSIONS: Our results demonstrated that hypoglycemia due to prolonged fasting disrupts BBB and produces brain edema in wild-type mice, highlighting the importance of brain health during treatment with prolonged fasting. [ABSTRACT FROM AUTHOR]
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- 2024
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11. Prediction of shear behavior of glass FRP bars-reinforced ultra-highperformance concrete I-shaped beams using machine learning.
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Ahmed, Asif, Uddin, Md Nasir, Akbar, Muhammad, Salih, Rania, Khan, Mohammad Arsalan, Bisheh, Hossein, and Rabczuk, Timon
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This study focuses on using various machine learning (ML) models to evaluate the shear behaviors of ultra-high-performance concrete (UHPC) beams reinforced with glass fiber-reinforced polymer (GFRP) bars. The main objective of the study is to predict the shear strength of UHPC beams reinforced with GFRP bars using ML models. We use four different ML models: support vector machine (SVM), artificial neural network (ANN), random forest (R.F.), and extreme gradient boosting (XGBoost). The experimental database used in the study is acquired from various literature sources and comprises 54 test observations with 11 input features. These input features are likely parameters related to the composition, geometry, and properties of the UHPC beams and GFRP bars. To ensure the ML models' generalizability and scalability, random search methods are utilized to tune the hyperparameters of the algorithms. This tuning process helps improve the performance of the models when predicting the shear strength. The study uses the ACI318M-14 and Eurocode 2 standard building codes to predict the shear capacity behavior of GFRP bars-reinforced UHPC I-shaped beams. The ML models' predictions are compared to the results obtained from these building code standards. According to the findings, the XGBoost model demonstrates the highest predictive test performance among the investigated ML models. The study employs the SHAP (SHapley Additive exPlanations) analysis to assess the significance of each input parameter in the ML models' predictive capabilities. A Taylor diagram is used to statistically compare the accuracy of the ML models. This study concludes that ML models, particularly XGBoost, can effectively predict the shear capacity behavior of GFRP bars-reinforced UHPC I-shaped beams. [ABSTRACT FROM AUTHOR]
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- 2024
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12. Compact rover surveying and laser scanning for BIM development.
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Jafri, Syed Riaz un Nabi, Hussain, Syed Murtaza, Ahmed, Asif, Rizvi, Syed Asher Hussain, Kazmi, Kumayl Hassan, and Iqbal, Jamshed
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FLOOR plans ,OPTICAL scanners ,BUILDING information modeling ,ARCHITECTURAL design ,BUILDING design & construction ,POINT cloud ,SCANNING systems - Abstract
This paper presents a custom made small rover based surveying, mapping and building information modeling solution. Majority of the commercially available mobile surveying systems are larger in size which restricts their maneuverability in the targeted indoor vicinities. Furthermore their functional cost is unaffordable for low budget projects belonging to developing markets. Keeping in view these challenges, an economical indigenous rover based scanning and mapping system has developed using orthogonal integration of two low cost RPLidar A1 laser scanners. All the instrumentation of the rover has been interfaced with Robot Operating System (ROS) for online processing and recording of all sensorial data. The ROS based pose and map estimations of the rover have performed using Simultaneous Localization and Mapping (SLAM) technique. The perceived class 1 laser scans data belonging to distinct vicinities with variable reflective properties have been successfully tested and validated for required structural modeling. Systematically the recorded scans have been used in offline mode to generate the 3D point cloud map of the surveyed environment. Later the structural planes extraction from the point cloud data has been done using Random Sampling and Consensus (RANSAC) technique. Finally the 2D floor plan and 3D building model have been developed using point cloud processing in appropriate software. Multiple interiors of existing buildings and under construction indoor sites have been scanned, mapped and modelled as presented in this paper. In addition, the validation of the as-built models have been performed by comparing with the actual architecture design of the surveyed buildings. In comparison to available surveying solutions present in the local market, the developed system has been found faster, accurate and user friendly to produce more enhanced structural results with minute details. [ABSTRACT FROM AUTHOR]
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- 2024
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13. Assessment of tube well water quality in selected residential areas in Khulna.
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TABASSUM, Sumaya, DRISTY, Jinat Tasnim, AHMED, Asif, and RIYAD, Riyadul Hashem
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WELL water ,WELLS ,WATER quality ,RESIDENTIAL areas ,TOTAL suspended solids ,ARSENIC removal (Water purification) ,DRINKING water - Abstract
Clean water is vital for sustainable development, fostering socio-economic growth, ecological stability, and human survival. The study aimed to evaluate the quality of tube well water in specific residential areas of Khulna for drinking purposes, comparing it with the standards of World Health Organization (WHO) and Bangladesh (BD). Twenty tube well water samples were collected from residential areas at depths of 700–1500 ft. The samples were tasted with about 20 parameters, including physical: color, taste, odor, total dissolved solids (TDS) and total suspended solids (TSS); chemical: acidity/alkalinity (pH), arsenic (As), electrical conductivity (EC), dissolved oxygen (DO), bicarbonate (HCO
3 – ), calcium (Ca2+ ), magnesium (Mg2+ ), sodium (Na+ ), chloride (Cl– ), iron (Fe), phosphate (PO4 3– ), sulfate (SO4 2– ), potassium (K+ ); and bacteriological parameters: total coliforms and E. coli bacteria. Most of the samples were found to have higher TDS (avg. 1380 mg/L), TSS (avg. 620 mg/L), Fe (avg. 20.2 mg/L), K+ (avg. 194.1 mg/L), and Na+ (avg. 439 mg/L) concentrations compared to the WHO and BD Standards. 90 to 95% of samples exhibited acceptable levels of EC, pH, DO, Mg2+ , Ca2+ , Cl– , and SO4 3– . The salinity levels in most of the samples were excessive to be used for drinking, and the levels were especially very high in samples S-01(Na+ 820 and Cl- 3195 mg/L) and S-04 (Na+ 660 and Cl- 2946 mg/L). The arsenic levels were found to be higher than acceptable limit in S-01 (0.086 mg/L) and S-04 (0.091 mg/L) as well. E. coli and other bacteria in a few samples (S-01, 04, 13, 16, 17, 19) were detected. [ABSTRACT FROM AUTHOR]- Published
- 2024
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14. Storage Stability Assessment of Indigenous Guava Fruits (Psidium guajava L.) cv. "Gola" in Response to γ-Irradiation.
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Yousaf, Ali Asad, Sarfraz, Kashif, Ahmed, Asif, Hassan, Imran, Ali, Haider, and Mehmood, Talat
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GUAVA ,FRUIT ,POLYPHENOL oxidase ,ENZYME kinetics ,ENZYMATIC browning ,SUPEROXIDE dismutase - Abstract
Postharvest losses in fruits and vegetables pose a key challenge to the global horticulture industry. Improved storage stability of horticultural commodities through irradiation is a technological intervention which has greater compliance over more than 60 foods and food products. The present study was intended to explore the effect of γ-irradiation doses on the postharvest quality of fresh guava fruits stored under ambient (temperature 20 ± 2 °C, RH 85%) conditions. Various storage specific quality attributes including physiological weight loss, respiration rate (CO
2 ), ethylene estimation, ripening index, fruit firmness, ascorbic acid, nutraceutical potential, and enzyme kinetics were evaluated during postharvest storage at four days of interval. The results indicated that the fruits irradiated at doses (0.8 kGy and 1.0 kGy) exhibited significant reduction in physiological parameters in contrast with untreated fruit samples. Firmness, total phenolic compounds, flavonoids, and radical scavenging activity were successfully retained in irradiated fruit samples up to twenty days of storage. The respiration and ethylene production rates were suppressed in irradiated guava fruits compared to control. Moreover, it has also been discovered that the fruits exposed to 1.0 kGy had considerably decreased the polyphenol oxidase (PPO) activity compared to nonirradiated fruits, thus resulting in lowering the enzymatic browning. Aside from that, irradiation guava fruits had considerably enhanced antioxidant enzyme activity (P ≤ 0.05) in terms of catalase, peroxidase, and superoxide dismutase. In conclusion, the study revealed that γ -rays irradiation doses up to 1.0 kGy might be considered effective to improve the postharvest storage of native guava fruits variety with intact nutritional attributes. [ABSTRACT FROM AUTHOR]- Published
- 2023
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15. Faster RCNN based robust vehicle detection algorithm for identifying and classifying vehicles.
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Alam, Md Khorshed, Ahmed, Asif, Salih, Rania, Al Asmari, Abdullah Faiz Saeed, Khan, Mohammad Arsalan, Mustafa, Noman, Mursaleen, Mohammad, and Islam, Saiful
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Deep convolutional neural networks (CNNs) have shown tremendous success in the detection of objects and vehicles in recent years. However, when using CNNs to identify real-time vehicle detection in a moving context remains difficult. Many obscured and truncated cars, as well as huge vehicle scale fluctuations in traffic photos, provide these issues. To improve the performance of detection findings, we used multiscale feature maps from CNN or input pictures with numerous resolutions to adapt the base network to match different scales. This research presents an enhanced framework depending on Faster R-CNN for rapid vehicle recognition which presents better accuracy and fast processing time. Research results on our custom dataset indicate that our recommended methodology performed better in terms of detection efficiency and processing time, especially in comparison to the earlier age of Faster R-CNN models. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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16. Anti-lung cancer drug discovery approaches by polysaccharides: an in silico study, quantum calculation and molecular dynamics study.
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Kobir, Md. Eleas, Ahmed, Asif, Roni, Md. Abul Hasan, Chakma, Unesco, Amin, Md. Ruhul, Chandro, Akhel, and Kumer, Ajoy
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- 2023
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17. Hybrid BO-XGBoost and BO-RF Models for the Strength Prediction of Self-Compacting Mortars with Parametric Analysis.
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Ahmed, Asif, Song, Wei, Zhang, Yumeng, Haque, M. Aminul, and Liu, Xian
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MORTAR ,SELF-consolidating concrete ,PREDICTION models ,FLEXURAL strength ,RANDOM forest algorithms ,SPACE exploration ,COMPRESSIVE strength - Abstract
Self-compacting mortar (SCM) has superior workability and long-term durable performance compared to traditional mortar. The strength of SCM, including both its compressive and flexural strengths, is a crucial property that is determined by appropriate curing conditions and mix design parameters. In the context of materials science, predicting the strength of SCM is challenging because of multiple influencing factors. This study employed machine learning techniques to establish SCM strength prediction models. Based on ten different input parameters, the strength of SCM specimens were predicted using two different types of hybrid machine learning (HML) models, namely Extreme Gradient Boosting (XGBoost) and the Random Forest (RF) algorithm. HML models were trained and tested by experimental data from 320 test specimens. In addition, the Bayesian optimization method was utilized to fine tune the hyperparameters of the employed algorithms, and cross-validation was employed to partition the database into multiple folds for a more thorough exploration of the hyperparameter space while providing a more accurate assessment of the model's predictive power. The results show that both HML models can successfully predict the SCM strength values with high accuracy, and the Bo-XGB model demonstrated higher accuracy (R
2 = 0.96 for training and R2 = 0.91 for testing phases) for predicting flexural strength with low error. In terms of compressive strength prediction, the employed BO-RF model performed very well, with R2 = 0.96 for train and R2 = 0.88 testing stages with minor errors. Moreover, the SHAP algorithm, permutation importance and leave-one-out importance score were used for sensitivity analysis to explain the prediction process and interpret the governing input variable parameters of the proposed HML models. Finally, the outcomes of this study might be applied to guide the future mix design of SCM specimens. [ABSTRACT FROM AUTHOR]- Published
- 2023
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18. A Survey on Sparsity Exploration in Transformer-Based Accelerators.
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Fuad, Kazi Ahmed Asif and Chen, Lizhong
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NATURAL language processing ,TRANSFORMER models ,COMPUTER vision ,DEEP learning ,PARALLEL processing ,APPLICATION software - Abstract
Transformer models have emerged as the state-of-the-art in many natural language processing and computer vision applications due to their capability of attending to longer sequences of tokens and supporting parallel processing more efficiently. Nevertheless, the training and inference of transformer models are computationally expensive and memory intensive. Meanwhile, utilizing the sparsity in deep learning models has proven to be an effective approach to alleviate the computation challenge as well as help to fit large models in edge devices. As high-performance CPUs and GPUs are generally not flexible enough to explore low-level sparsity, a number of specialized hardware accelerators have been proposed for transformer models. This paper provides a comprehensive review of hardware transformer accelerators that have been proposed to explore sparsity for computation and memory optimizations. We classify existing works based on the strategies of utilizing sparsity and identify their pros and cons in those strategies. Based on our analysis, we point out promising directions and recommendations for future works on improving the effective sparse execution of transformer hardware accelerators. [ABSTRACT FROM AUTHOR]
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- 2023
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19. Management of Paraquat Poisoning--The Way Forward.
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Ahmed, Asif, Prasad, Anu, and Bhattacharjee, Agnideb
- Subjects
THERAPEUTIC use of vitamin E ,THERAPEUTIC use of antioxidants ,THERAPEUTIC use of vitamin C ,HERBICIDES ,BLOOD filtration ,HEMODIALYSIS ,HEMOPERFUSION ,ACETYLCYSTEINE ,GASTRIC lavage ,PYRIDINE ,ARTIFICIAL respiration ,COMBINED modality therapy ,METHYLPREDNISOLONE ,POISONING ,DEXAMETHASONE ,CYCLOPHOSPHAMIDE ,IMMUNOSUPPRESSION - Published
- 2024
- Full Text
- View/download PDF
20. Computation and memory optimized spectral domain convolutional neural network for throughput and energy-efficient inference.
- Author
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Rizvi, Shahriyar Masud, Rahman, Ab Al-Hadi Ab, Sheikh, Usman Ullah, Fuad, Kazi Ahmed Asif, and Shehzad, Hafiz Muhammad Faisal
- Subjects
CONVOLUTIONAL neural networks ,ENERGY consumption - Abstract
Conventional convolutional neural networks (CNNs) present a high computational workload and memory access cost (CMC). Spectral domain CNNs (SpCNNs) offer a computationally efficient approach to compute CNN training and inference. This paper investigates CMC of SpCNNs and its contributing components analytically and then proposes a methodology to optimize CMC, under three strategies, to enhance inference performance. In this methodology, output feature map (OFM) size, OFM depth or both are progressively reduced under an accuracy constraint to compute performance-optimized CNN inference. Before conducting training or testing, it can provide designers guidelines and preliminary insights regarding techniques for optimum performance, least degradation in accuracy and a balanced performance–accuracy trade-off. This methodology was evaluated on MNIST and Fashion MNIST datasets using LeNet-5 and AlexNet architectures. When compared to state-of-the-art SpCNN models, LeNet-5 achieves up to 4.2× (batch inference) and 4.1× (single-image inference) higher throughputs and 10.5× (batch inference) and 4.2× (single-image inference) greater energy efficiency at a maximum loss of 3% in test accuracy. When compared to the baseline model used in this study, AlexNet delivers 11.6× (batch inference) and 5× (single-image inference) increased throughput and 25× (batch inference) and 8.8× (single-image inference) more energy-efficient inference with just 4.4% reduction in accuracy. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
21. Surface settlement induced by horizontal directional drilling.
- Author
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Ahmed, Asif, Islam, Md Azijul, Alam, Md Zahangir, and Quazi, Hashmi S.
- Subjects
DIRECTIONAL drilling ,BOREHOLES ,MODULUS of elasticity ,POISSON'S ratio ,EMPIRICAL research - Abstract
Horizontal directional drilling (HDD) is a widely used trenchless method for underground utility connections. The associated ground settlement triggered by HDD depends on the size, types, and surface texture of pipe, diameter of borehole, and soil conditions. The present study investigates the surface settlement due to the construction of a 1067 mm diameter HDD, which will replace an existing sewer siphon under the SR-60 highway in Chino, California using empirical, and numerical methods. Based on the results obtained from the subsurface investigation, an empirical analysis was conducted first. followed by numerical modeling of the HDD using PLAXIS 2D software. A careful comparison between two different methods indicated closer values of surface settlement between the empirical method (7.3 mm) and the numerical modeling (4.6 mm). In addition, the shape of surface settlement and horizontal settlement curves for the empirical and numerical methods was found to be similar. The minor discrepancy between the two methods resulted as the numerical model can host several soil layers whereas the empirical equation can use only one type of soil. Finally, a parametric study was conducted to evaluate the effect of borehole cover depth, size, and soil parameters on surface settlement. It was observed that soil strength parameters yielded a greater effect on surface movement, whereas modulus of elasticity has a relatively smaller influence with zero contribution from Poisson's ratio. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
22. Fabricating 2 piece closed hollow obturator with elastomeric impression material: An innovative dental technique.
- Author
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Ahmed, Asif and Devi, Mutum Sangeeta
- Subjects
DENTAL impression materials ,ELASTOMERS ,DENTAL technicians ,MAXILLECTOMY - Abstract
Maxillectomy defects are the most common results in oro-nasal communication, which leads to an expected change in speech tone, difficulty in mastication, and deglutition. These affect the quality of life of the patient and also impact them psychosocially in a long run. The most common management of maxillectomy patients for both complete and partial is by maxillary obturator prosthesis. To reduce the weight of the obturators various procedures of hollowing are present in literature. In this article, we will discuss an alternate and innovative laboratory technique for the fabrication of closed hollow obturator which will reduce the time of both dental technicians and clinicians. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
23. Comparison of Side to Side Staple Versus Hand Sewn Gastro Esophageal Anastomosis in Cases of Oesophagectomy in CA Esophagus.
- Author
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Khan, Mohammad Abid, Baseer, Abdul, Aslam, Tahir, Aslam, Viqar, and Ahmed, Asif
- Subjects
ESOPHAGEAL cancer ,ESOPHAGUS ,ESOPHAGECTOMY ,SQUAMOUS cell carcinoma ,SEWING - Abstract
Objective: To compare outcomes of side-to-side staple versus hand-sewn esophago-gastric anastomosis in esophagectomy patients with carcinoma of esophagus after subtotal esophagectomy along with gastric tube reconstruction. Study Design: Retrospective cross-sectional study. Place and Duration of Study: Lady Reading Hospital, Peshawar Pakistan, from July 2019 to June 2020. Methodology: After ethical approval, medical records of patients that underwent stapled/hand sewn gastro esophageal anastomosis due to carcinoma esophagus were included. Inoperable Ca esophagus and with thoracic anastomosis were excluded. Each anastomotic technique was applied on 50 patients randomly. The variables of study included demographic, anastomotic leak, anastomotic stricture, operative time, and other complications. All the cases were followed up for 1 year. SPSS version 26.0 was used for data analysis. Result: From 100 patients, 56 were males and 34 females. Age ranged from 15 to 80 years with mean age of 48.5 and 51.1 respectively in two groups. In 42 cases tumor was present in lower end, middle third in 30 and middle lower third of gastro esophageal junction in 28 cases. Histo-pathologically 58 cases were adenocarcinoma, 31 squamous cell carcinoma and 11 adeno squamous carcinoma. The anastomosis time in group I was 6.8±.22 minutes while in group II was 13.2±1.71 minutes (p0.04). None of the patients in group I, having stapled anastomosis were found to have anastomotic leakage or stricture formation after 1 year of follow up while 04 patients in group II were reported to have anastomotic leakage and 06 patients had anastomotic stricture formation (p-<0.01). Conclusion: Side by side stapled anastomosis technique was far superior to hand-sewn technique in terms of the time taken for anastomosis to be completed and patient outcomes (anastomotic leakage and stricture formation). [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
24. On-going consequences of in utero exposure of Pb: An epigenetic perspective.
- Author
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Tasin, Fahim Rejanur, Ahmed, Asif, Halder, Debasish, and Mandal, Chanchal
- Subjects
LEAD exposure ,FETUS ,FETAL membranes ,FETAL abnormalities ,EPIGENETICS ,LEAD - Abstract
Epigenetic modifications by toxic heavy metals are one of the intensively investigated fields of modern genomic research. Among a diverse group of heavy metals, lead (Pb) is an extensively distributed toxicant causing an immense number of abnormalities in the developing fetus via a wide variety of epigenetic changes. As a divalent cation, Pb can readily cross the placental membrane and the fetal blood brain barrier leading to far-reaching alterations in DNA methylation patterns, histone protein modifications, and micro-RNA expression. Over recent years, several human cohorts and animal model studies have documented hypermethylation and hypomethylation of developmental genes along with altered DNA methyl-transferase expression by in utero Pb exposure in a dose-, duration-, and sex-dependent manner. Modifications in the expression of specific histone acetyltransferase enzymes along with histone acetylation and methylation levels have been reported in rodent and murine models. Apart from these, down-regulation and up-regulation of certain microRNAs crucial for fetal development have been shown to be associated with in utero Pb exposure in human placenta samples. All these modifications in the developing fetus during the prenatal and perinatal stages reportedly caused severe abnormalities in early or adult age, such as impaired growth, obesity, autism, diabetes, cardiovascular diseases, risks of cancer development, and Alzheimer's disease. In this review, currently available information on Pb-mediated alterations in the fetal epigenome is summarized. Further research on Pb-induced epigenome modification will help to understand the mechanisms in detail and will enable us to formulate safety guidelines for pregnant women and developing children. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
25. Impact of COVID-19 on Capstone Projects Outcomes.
- Author
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Ahmed, Asif
- Subjects
CAPSTONE courses ,CIVIL engineering ,STUDENT projects ,EDUCATIONAL outcomes ,COVID-19 pandemic - Abstract
Capstone Projects, CTC 490, is a mandatory course for all Civil Engineering Technology students during their senior year. This specific course is designed to apply cumulative experiences gathered from wide range of courses in the curriculum. The students analyze and design real life civil engineering project, write a written report followed by an oral presentation. However, during the COVID-19 pandemic, student learning outcomes were significantly disrupted as the plan of study changed to online mode from March 2020. The purpose of the current study is to document the students' learning experiences of the capstone design course during the pandemic year. As the course is so comprehensive in nature, wide range of student learning assessment is possible from this course. Data were collected from Fall 2020 and Spring 2021 semester to assess the student outcomes in the category of communication with the teammates, fulfill roles and responsibilities, and listening to the teammates. The scales of one to four (1-not acceptable, 2- below standards, 3- meets standards, 4- exemplary) were chosen so that the instructor had a clear view to make a decision whether the expectations were met or not. The measure of successful performance in each attribute was achieving a score of 3 or 4. A benchmark of 70% was selected to gage the level of success. The results showed that the student outcomes were impacted most in the communications category. The level of success in the capstone rubric were documented and connected with the related program outcomes of the ETAC/ABET criteria. Outcomes of this study will be helpful in planning to teach such kind of course in situation like pandemic or other situations out of our control. [ABSTRACT FROM AUTHOR]
- Published
- 2022
26. Edge-Based Heuristics for Optimizing Shortcut-Augmented Topologies for HPC Interconnects.
- Author
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Fuad, Kazi Ahmed Asif, Zeng, Kai, and Chen, Lizhong
- Subjects
HIGH performance computing ,TOPOLOGY ,HEURISTIC ,SPACE - Abstract
Interconnection network topology is critical for the overall performance of HPC systems. While many regular and irregular topologies have been proposed in the past, recent work has shown the promise of shortcut-augmented topologies that offer multi-fold reduction in network diameter and hop count over conventional topologies. However, the large number of possible shortcuts creates an enormous design space for this new type of topology, and existing approaches are extremely slow and do not find shortcuts that are globally optimal. In this paper, we propose an efficient heuristic approach, called EdgeCut, which generates high-quality shortcut-augmented topologies. EdgeCut can identify more globally useful shortcuts by making its considerations from the perspective of edges instead of vertices. An additional implementation is proposed that approximates the costly all-pair shortest paths calculation, thereby further speeding up the scheme. Quantitative comparisons over prior work show that the proposed approach achieves a 1982 × reduction in search time while generating better or equivalent topologies in 94.9% of the evaluated cases. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
27. Characterization and calibration of multiple 2D laser scanners.
- Author
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Jafri, Syed Riaz un Nabi, Shamim, Sheraz, Faraz, Sadia Muniza, Ahmed, Asif, Yasir, Syed Muhammad, and Iqbal, Jamshed
- Subjects
OPTICAL scanners ,KALMAN filtering ,BACKPACKS ,SCANNING systems ,CALIBRATION - Abstract
This paper presents the comparative evaluation of multiple compact and lightweight 2D laser scanners for their possible backpack based scanning and mapping applications. These scanners include Hokuyo URG-04LX, Slamtec RPLidar A1-M8 and Hokuyo UTM-30LX-EW scanners. Since the technical datasheets provide general information and limited working details, this research presents a thorough study on the performance of each scanner related explicitly to indoor mapping operations. A series of scanning experiments have been performed for the characterization of each scanner using statistical analysis. During the testing, all the scanning data has been recorded using Robot Operating System (ROS) and then computed in offline processing. In initial tests, each scanner's drift effect on range measurements has been tested and presented in the relevant section of the paper. In continuation, the effect of various scanning distances on measurement accuracy has been evaluated and discussed. Later the impact of various materials typically found in indoor vicinities and their respective properties of color and smoothness have been tested and provided in the paper. Finally, a Kalman Filtering based mathematical formulation has been utilized to calibrate each scanner and to reduce the measuring uncertainties as observed in various tests for each scanner. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
28. In-silico screening of bioactive phytopeptides for novel anti-ageing therapeutics.
- Author
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Salekeen, Rahagir, Ahmed, Asif, Islam, Md Emdadul, Billah, Md Morsaline, Rahman, Hafizur, and Islam, Kazi Mohammed Didarul
- Published
- 2022
- Full Text
- View/download PDF
29. The Therapeutic Potential of Milk Extracellular Vesicles on Colorectal Cancer.
- Author
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Babaker, Manal A., Aljoud, Fadwa A., Alkhilaiwi, Faris, Algarni, Abdulrahman, Ahmed, Asif, Khan, Mohammad Imran, Saadeldin, Islam M., and Alzahrani, Faisal A.
- Subjects
EXTRACELLULAR vesicles ,COLORECTAL cancer ,CAMEL milk ,COMPOSITION of milk ,MILK ,DEVELOPING countries - Abstract
Colorectal cancer remains one of the leading prevalent cancers in the world and is the fourth most common cause of death from cancer. Unfortunately, the currently utilized chemotherapies fail in selectively targeting cancer cells and cause harm to healthy cells, which results in profound side effects. Researchers are focused on developing anti-cancer targeted medications, which is essential to making them safer, more effective, and more selective and to maximizing their therapeutic benefits. Milk-derived extracellular vesicles (EVs) from camels and cows have attracted much attention as a natural substitute product that effectively suppresses a wide range of tumor cells. This review sheds light on the biogenesis, methods of isolation, characterization, and molecular composition of milk EVs as well as the therapeutic potentials of milk EVs on colorectal cancer. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
30. Predicting multi-enzyme inhibition in the arachidonic acid metabolic network by Heritiera fomes extracts.
- Author
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Salekeen, Rahagir, Mou, Sadia Noor, Islam, Md Emdadul, Ahmed, Asif, Billah, Md Morsaline, Rahman, S. M. Mahbubur, and Islam, Kazi Mohammed Didarul
- Published
- 2022
- Full Text
- View/download PDF
31. The impact of COVID‐19 on pregnancy and therapeutic drug development.
- Author
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Abbas‐Hanif, Allyah, Rezai, Homira, Ahmed, Syed Faraz, and Ahmed, Asif
- Subjects
DRUG development ,MEDICAL personnel ,VACCINE trials ,COVID-19 ,PREGNANT women ,PREECLAMPSIA ,ECLAMPSIA - Abstract
Emerging data show that pregnant women with COVID‐19 are at significantly higher risk of severe outcomes compared with non‐pregnant women of similar age. This review discusses the invaluable insight revealed from vaccine clinical trials in women who were vaccinated and inadvertently became pregnant during the trial period. It further explores a number of clinical avenues in their management and proposes a drug development strategy in line with clinical trials for vaccines and drug treatments for the drug development community. Little is known of the long‐term effects of COVID‐19 on the mother and the baby. Our hypothesis that COVID‐19 predisposes pregnant women to pre‐eclampsia or hypertensive disorders during pregnancy is supported by a clinical study, and this may also adversely impact a woman's cardiovascular disease risk later in life. It may also increase a woman's risk of pre‐eclampsia in subsequent pregnancy. This is an ever‐evolving landscape, and early knowledge for healthcare providers and drug innovators is offered to ensure benefits outweigh the risks. COVID‐19 mRNA vaccines appear to generate robust humoral immunity in pregnant and lactating women. This novel approach to vaccination also offers new ways to therapeutically tackle disorders of many unmet medical needs. LINKED ARTICLES: This article is part of a themed issue on The second wave: are we any closer to efficacious pharmacotherapy for COVID 19? (BJP 75th Anniversary). To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v179.10/issuetoc [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
32. Evaluate the Total Mechanical Gastroesophageal Anastomosis for Carcinoma Esophagus.
- Author
-
Khan, Muhammad Abid, Aslam, Tahir, Ahmed, Asif, Aslam, Viqar, and Tahir, Imran
- Subjects
ESOPHAGUS ,ESOPHAGEAL cancer ,CARCINOMA ,DEATH rate ,CANCER diagnosis - Abstract
Objective: To evaluate total mechanical gastroesophageal anastomosis in patients with carcinoma of esophagus. Study Design: Cross sectional study. Place and Duration of Study: Department of Surgery, Bolan Medical University, from Jan 2020 to Jun 2021. Methodology: Total of 75 patients were included consecutively in this observational cross sectional study involving patients diagnosed with esophageal cancer and awaiting to undergo esophagiectomy with mechanical anastomosis in-between 18 to 60 years and were ASA I and II were included. Patients that were ASA III or IV and having any systemic disorder and those that refused to participate were excluded. SPSS version 23.0 was used for data analysis keeping p-value <0.05 as significant. Results: Mean age of patients was 58.31 ± 6.2 years wherein 42(56%) males and 33(44%) females. 29 (38.7%) of patients were ASA I while 46 (61.3%) were ASA II. Mean operative time of patients was 240 ± 65.2 minutes while mean blood loss was 205 ± 32.3 ml. Regarding anastomotic leakage, minor (type I) leakage was observed in 05(6.7%) of patients while major (type II or III) leakage was seen in 03(4%) of patients. Anastomotic dilatation, stricture formation and death were reported in 01(1.33%) patient each. Conclusion: Total mechanical gastro-esophageal anastomosis was found to have safe, less time consuming and with minimal post-operative anastomotic leakage or stricture formation and morbidity. [ABSTRACT FROM AUTHOR]
- Published
- 2022
33. Field monitoring and model predicted water balance of monolithic cover.
- Author
-
de Campos, T.M.P., Marinho, F.A.M., Gitirana Jr., G.F.N., Mascarenha, M.M.A., Alam, Md Jobair Bin, Ahmed, Asif, Islam, Md Aminul, Rahman, Naima, and Hossain, Md Sahadat
- Published
- 2021
- Full Text
- View/download PDF
34. Estimation of percolation of water balance cover using field scale unsaturated soil parameter.
- Author
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de Campos, T.M.P., Marinho, F.A.M., Gitirana Jr., G.F.N., Mascarenha, M.M.A., Alam, Md Jobair Bin, Ahmed, Asif, Hossain, Md Sahadat, and Rahman, Naima
- Published
- 2021
- Full Text
- View/download PDF
35. Comparison of numerical modeling results from laboratory and field obtained unsaturated flow parameters.
- Author
-
de Campos, T.M.P., Marinho, F.A.M., Gitirana Jr., G.F.N., Mascarenha, M.M.A., Ahmed, Asif, Alam, Md Jobair Bin, Islam, Md Azijul, and Hossain, MD Sahadat
- Published
- 2021
- Full Text
- View/download PDF
36. Estimation of unsaturated flow parameters and hysteresis curve from field instrumentation.
- Author
-
de Campos, T.M.P., Marinho, F.A.M., Gitirana Jr., G.F.N., Mascarenha, M.M.A., Ahmed, Asif, Alam, Md Jobair Bin, Pandey, Pratibha, and Hossain, MD Sahadat
- Published
- 2021
- Full Text
- View/download PDF
37. Microwave power penetration enhancement inside an inhomogeneous human head.
- Author
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Rokunuzzaman, Md., Ahmed, Asif, Baum, Thomas, and Rowe, Wayne S. T.
- Subjects
DIELECTRIC waveguides ,MICROSTRIP antennas ,MICROWAVES ,ANTENNA feeds ,ANTENNA design ,HEAD - Abstract
The penetration of microwave power inside a human head model is improved by employing a dielectric loaded rectangular waveguide as the transmission source. A multi-layer reflection model is investigated to evaluate the combined material characteristics of different lossy human head tissues at 2.45 GHz. A waveguide loaded with a calculated permittivity of 3.62 is shown to maximise the microwave power penetration at the desired frequency. A Quartz (SiO
2 ) loaded rectangular waveguide fed by a microstrip antenna is designed to validate the power penetration improvement inside an inhomogeneous human head phantom. A measured 1.33 dB power penetration increment is observed for the dielectric loaded waveguide over a standard rectangular waveguide at 50 mm inside the head, with an 81.9% reduction in the size of the transmission source. [ABSTRACT FROM AUTHOR]- Published
- 2021
- Full Text
- View/download PDF
38. Success rate of Remdesivir, Convalescent Plasma, and Tocilizumab in moderate to severe Covid-19 pneumonia: our experience in a tertiary care center.
- Author
-
Mohanty, Bijaya, Sunder, Ashok, Satyanarayan, Bhagyalakshmi, Kumar, Manish, Shukla, Rajiv, and Ahmed, Asif
- Subjects
CONVALESCENT plasma ,REMDESIVIR ,COVID-19 ,SURVIVAL rate ,MEDICAL personnel ,BLOOD transfusion reaction - Abstract
Introduction: After the first case of Covid-19 was identified in Wuhan City, China, the numbers increased rapidly all over the world putting a huge burden on the entire healthcare system. Managing these cases posed a great challenge to the treating clinicians in the absence of targeted therapy. At this juncture, few modalities got approved as EUA (Emergency use under authorization) drugs namely Remdesivir, Convalescent Plasma (CP), and Tocilizumab (TCZ) to treat this deadly disease. Aim: To analyze the success rates of EUA therapies for Covid-19 pneumonia in our hospital. Materials and Methods: This was a prospective observational study conducted from April 2020 to October 2020 in the department of Medicine at Tata Main Hospital, Jamshedpur, Jharkhand. All adults with moderate to severe Covid-19 as per the WHO criteria were enrolled in the study with their informed consent. Patients with estimated glomerular filtration rate <30 mL/min, deranged liver function tests, electrocardiographic abnormalities, and deranged hematological parameters were excluded from the study. Thorough clinical evaluation was done in all cases. Routine investigations together with CRP, LDH, serum Ferritin, D Dimer and IL6, Chest X-Ray, and HRCT thorax were done in all cases. ECG was done in all cases and 2D-ECHO in selected ones. Depending on their clinical and radiological criteria, patients were treated with various modalities approved under EUA with close monitoring of clinical, biochemical, and radiological parameters. Presenting symptoms, clinical findings, co-morbidities, laboratory parameters, and radiological assessment were analyzed, and statistical analysis was done. The survival rate and in-hospital mortality was analyzed. Observations and Results: We had a total of 448 patients who were included in our study, out of which 326 were males and 122 were females with a male to female ratio of 2.7:1. Their age varied between 16 and 91 years with an average age of 51.4 years with a standard deviation (SD) of +/- 6.4 years. About 255 patients (57%) received only Remdesivir (176 males, 79 females), 139 (105 males, 35 females) patients (31%) received Remdesivir along with two units of CP, and 38 (32 males, 6 females) patients received a combination of Remdesivir, CP, and TCZ. All patients in our study tolerated the drugs well. About 5% of cases who received CP had minor transfusion reactions. One patient had TRALI and three patients had TACO, which was managed aggressively. Asymptomatic transaminitis was seen in 36% patients. The survival rate in patients treated with Remdesivir was 78%, those with Remdesivir and CP was 44%, and those with all three was 13%. The mean length of stay was 14.23 days with a SD of 9.06 days in patients treated with TCZ in comparison to other two modalities, which was 13.88 days with a standard variation of +/- 8.71 days in Remdesivir and 13.88 days with a SD of 8.73 days in patients treated with CP that was stastically significant. Conclusions: Though the success rate of various drugs under EUA varies in different studies from all over the world, the data to support their use are encouraging. We also observed satisfying results in our study specially with the use of Remdesivir. Therefore, EUA agents should be used early to fight against COVID-19 along with the other measures as per the protocol laid by ICMR and MoHFW. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
39. Potential detrimental role of soluble ACE2 in severe COVID‐19 comorbid patients.
- Author
-
Rahman, Mohammad Mahmudur, Hasan, Maruf, and Ahmed, Asif
- Abstract
Summary: Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) enters the host cell by binding to angiotensin‐converting enzyme 2 (ACE2) receptor. Other important proteins involved in this process include disintegrin and metalloproteinase domain‐containing protein 17 (ADAM17) also known as tumour necrosis factor‐α‐converting enzyme and transmembrane serine protease 2. ACE2 converts angiotensin II (Ang II) to angiotensin (1–7), to balance the renin angiotensin system. Membrane‐bound ACE2 ectodomain shedding is mediated by ADAM17 upon viral spike binding, Ang II overproduction and in several diseases. The shed soluble ACE2 (sACE2) retains its catalytic activity, but its precise role in viral entry is still unclear. Therapeutic sACE2 is claimed to exert dual effects; reduction of excess Ang II and blocking viral entry by masking the spike protein. Nevertheless, the paradox is why SARS‐CoV‐2 comorbid patients struggle to attain such benefit in viral infection despite having a high amount of sACE2. In this review, we discuss the possible detrimental role of sACE2 and speculate on a series of events where protease primed or non‐primed virus–sACE2 complex might enter the host cell. As extracellular virus can bind many sACE2 molecules, sACE2 level could be reduced drastically upon endocytosis by the host cell. A consequential rapid rise in Ang II level could potentially aggravate disease severity through Ang II‐angiotensin II receptor type 1 (AT1R) axis in comorbid patients. Hence, monitoring sACE2 and Ang II level in coronavirus disease 2019 comorbid patients are crucial to ensure safe and efficient intervention using therapeutic sACE2 and vaccines. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
40. Hyperglycaemia up-regulates placental growth factor (PlGF) expression and secretion in endothelial cells via suppression of PI3 kinase-Akt signalling and activation of FOXO1.
- Author
-
Sissaoui, Samir, Egginton, Stuart, Ting, Ling, Ahmed, Asif, and Hewett, Peter W.
- Subjects
HYPERGLYCEMIA ,PLACENTAL growth factor ,PROTEIN expression ,ENDOTHELIAL cells ,PHOSPHATIDYLINOSITOL 3-kinases - Abstract
Placenta growth factor (PlGF) is a pro-inflammatory angiogenic mediator that promotes many pathologies including diabetic complications and atherosclerosis. Widespread endothelial dysfunction precedes the onset of these conditions. As very little is known of the mechanism(s) controlling PlGF expression in pathology we investigated the role of hyperglycaemia in the regulation of PlGF production in endothelial cells. Hyperglycaemia stimulated PlGF secretion in cultured primary endothelial cells, which was suppressed by IGF-1-mediated PI3K/Akt activation. Inhibition of PI3K activity resulted in significant PlGF mRNA up-regulation and protein secretion. Similarly, loss or inhibition of Akt activity significantly increased basal PlGF expression and prevented any further PlGF secretion in hyperglycaemia. Conversely, constitutive Akt activation blocked PlGF secretion irrespective of upstream PI3K activity demonstrating that Akt is a central regulator of PlGF expression. Knock-down of the Forkhead box O-1 (FOXO1) transcription factor, which is negatively regulated by Akt, suppressed both basal and hyperglycaemia-induced PlGF secretion, whilst FOXO1 gain-of-function up-regulated PlGF in vitro and in vivo. FOXO1 association to a FOXO binding sequence identified in the PlGF promoter also increased in hyperglycaemia. This study identifies the PI3K/Akt/FOXO1 signalling axis as a key regulator of PlGF expression and unifying pathway by which PlGF may contribute to common disorders characterised by endothelial dysfunction, providing a target for therapy. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
41. Oral manifestation of post cancer therapy.
- Author
-
Devi, Mutum Sangeeta and Ahmed, Asif
- Subjects
ORAL manifestations of general diseases ,CANCER treatment ,SMOKELESS tobacco ,ORAL mucosa ,ORAL cancer ,CANCER radiotherapy - Abstract
Oral cancer has become serious health issues. It is owing to a variety of factors including poor hygiene, tobacco usage, chewing tobacco, smoking, and others. Along with surgery and chemotherapy, the most common treatments include radiation therapy and chemotherapy. Patients with cancer may experience oral toxic effects as a result of antineoplastic therapy such as radiotherapy and chemotherapy. A variety of factors influence radiation, including the oral mucosa’s fast cell turnover rate, the richness and complexity of the oral microbiota, and soft tissue stress during normal mouth function. The present literature review is for awareness regarding the main oral manifestation secondary to post cancer therapy. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
42. Thermo-mechanical and optical characteristics of cold-rolled copper with natural melting impurities.
- Author
-
Ahmed, Asif, Iqbal, Nasim, Kaiser, M. S., Ahmed, S. Reaz, Alam, Muhammad Mahbubul, Rahman, Muhammad Ashiqur, and Ali, Mohammad
- Subjects
COPPER ,MELTING ,THERMAL conductivity ,THERMAL properties ,REFLECTANCE - Abstract
Effect of natural impurities induced in repeated melting is investigated on thermo-mechanical and reflectance characteristics of commercially available pure copper. Copper samples of three different material characteristics are prepared, which are obtained from direct copper ingot, from melted copper and finally from re-melted copper. Samples are then cold rolled in three different stages as well as age hardened by isochronal and isothermal annealing. Series of experiments are then conducted to measure the changes in microhardness, thermal conductivity, reflectance and microstructure of the samples as a function of with and without melting. Most of the thermal and mechanical properties are found to be affected quite significantly by the melting impurities especially when the samples are cold rolled together with age hardening. The reflectance spectrum is also found to be changed with the increase of impurities induced by repeated melting of copper. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
43. USH2A gene variants cause Keratoconus and Usher syndrome phenotypes in Pakistani families.
- Author
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Ahmed, Asif Naveed, Tahir, Raheel, Khan, Niamat, Ahmad, Mushtaq, Dawood, Muhammad, Basit, Abdul, Yasin, Muhammad, Nowshid, Maha, Marwan, Muhammad, Sultan, Komal, and Saleha, Shamim
- Subjects
USHER'S syndrome ,PAKISTANIS ,PHENOTYPES ,KERATOCONUS ,RECESSIVE genes ,GLYCOGEN storage disease type II - Abstract
Background: Retinitis pigmentosa (RP) is the most common inherited retinal dystrophy, affecting approximately 1 in 4000 individuals worldwide. The most common form of syndromic RP is Usher syndrome (USH) accounting for approximately 20-30 % of RP cases. Mutations in the USH2A gene cause a significant proportion of recessive non-syndromic RP and USH type II (USH2). This study aimed to determine the causative role of the USH2A gene in autosomal recessive inherited ocular diseases and to establish genotype-phenotype correlation associated with USH2A variants.Methods: We performed direct Sanger sequencing and co-segregation analysis of the USH2A gene to identify disease causing variants in a non-syndromic RP family, two USH2 families and two Keratoconus (KC) families.Results: Disease causing variants in the USH2A gene were identified in two families displayed KC and USH2 phenotypes. A novel variant c.4029T > G, p.Asn1343Lys in the USH2A gene was detected in a Pakistani family with KC phenotype. In addition, a missense variant (c.7334 C > T, p. Ser2445Phe) in the USH2A gene was found segregating in another Pakistani family with USH2 phenotype. Homozygosity of identified missense USH2A variants was found associated with autosomal recessive inherited KC and USH2 phenotypes in investigated families. These variants were not detected in ethnically matched healthy controls. Moreover, the USH2A variants were predicted to be deleterious or potentially disease causing by PolyPhen-2, PROVEAN and SIFT.Conclusions: This study provided first evidence for association of a novel USH2A variant with KC phenotype in a Pakistani family as well as established the phenotype-genotype correlation of a USH2A variant (c.7334 C > T, p. Ser2445Phe) with USH2 phenotype in another Pakistani family. The phenotype-genotype correlations established in present study may improve clinical diagnosis of affected individuals for better management and counseling. [ABSTRACT FROM AUTHOR]- Published
- 2021
- Full Text
- View/download PDF
44. Quality Metrics in Acute Stroke: Time to Own.
- Author
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Ahmed, Asif
- Subjects
STROKE prognosis ,KEY performance indicators (Management) ,SERIAL publications ,QUALITY assurance ,STROKE rehabilitation ,CLINICAL medicine ,DISEASE management - Published
- 2023
- Full Text
- View/download PDF
45. Validation and development of models using clinical, biochemical and ultrasound markers for predicting pre-eclampsia: an individual participant data meta-analysis.
- Author
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Snell, Kym I. E., Smuk, Melanie, Hooper, Richard, Chan, Claire L., Ahmed, Asif, Chappell, Lucy C., von Dadelszen, Peter, Dodds, Julie, Green, Marcus, Kenny, Louise, Khalil, Asma, Khan, Khalid S., Mol, Ben W., Myers, Jenny, Poston, Lucilla, Thilaganathan, Basky, Staff, Anne C., Smith, Gordon CS, and Ganzevoort, Wessel
- Published
- 2020
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46. A novel 4D digital holographic PIV/PTV (4D-DHPIV/PTV) methodology using iterative predictive inverse reconstruction.
- Author
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Sun, Bihai, Ahmed, Asif, Atkinson, Callum, and Soria, Julio
- Subjects
LAMINAR flow ,DIGITAL filters (Mathematics) ,COMPUTER performance ,DIGITAL image processing ,ARRAY processing - Abstract
Digital imaging array technology and processing power are continuously improving and have reached a state where 4-dimensional (i.e. time-resolved 3C-3D) digital holographic PIV/PTV (4D-DHPIV/PTV) methods can be considered for macro fluid mechanics and turbulence investigations. This paper presents an in-line 4D-DHPIV/PTV methodology, which in addition to including the standard digital hologram reconstruction, incorporates advanced digital filtering to remove the virtual image effect, 3-dimensional volume deconvolution to reduce the depth-of-focus problem and the virtual image, followed by an efficient one-pass 3-dimensional clustering algorithm coupled with a predictive inverse reconstruction approach to increase the particle reconstruction dynamic range and 3-dimensional reconstruction domain, which is accelerated using particle position prediction. In addition to the presentation of the details of this novel 4D-DHPIV/PTV method, performance results pertaining to bias particle position error and the uncertainty associated with the particle position are presented as a function of (i) particle concentration and (ii) the shot noise present in the digitally recorded hologram. An experiment to measure laminar micro-channel flow has been performed to demonstrate the 4D-DHPIV/PTV methodology. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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47. Effectiveness of the Laser Application in Temporomandibular Joint Disorder: A Systematic Review of 1172 Patients.
- Author
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Zwiri, Abdalwhab, Alrawashdeh, Manal Ahmad, Khan, Mohammad, Ahmad, Wan Muhamad Amir W., Kassim, Nur Karyatee, Ahmed Asif, Jawaad, Suan Phaik, Khoo, Husein, Adam, and Ab-Ghani, Zuryati
- Published
- 2020
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- View/download PDF
48. Ethnobotany and Antimicrobial Peptides From Plants of the Solanaceae Family: An Update and Future Prospects.
- Author
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Afroz, Mohasana, Akter, Sanzida, Ahmed, Asif, Rouf, Razina, Shilpi, Jamil A., Tiralongo, Evelin, Sarker, Satyajit D., Göransson, Ulf, and Uddin, Shaikh Jamal
- Subjects
ANTIMICROBIAL peptides ,DRUG resistance in bacteria ,SOLANACEAE ,ETHNOBOTANY ,CELL aggregation ,CATHELICIDINS ,HOST plants ,DEFENSINS - Abstract
The Solanaceae is an important plant family that has been playing an essential role in traditional medicine and human nutrition. Members of the Solanaceae are rich in bioactive metabolites and have been used by different tribes around the world for ages. Antimicrobial peptides (AMPs) from plants have drawn great interest in recent years and raised new hope for developing new antimicrobial agents for meeting the challenges of antibiotic resistance. This review aims to summarize the reported AMPs from plants of the Solanaceae with possible molecular mechanisms of action as well as to correlate their traditional uses with reported antimicrobial actions of the peptides. A systematic literature study was conducted using different databases until August 2019 based on the inclusion and exclusion criteria. According to literature, a variety of AMPs including defensins, protease inhibitor, lectins, thionin-like peptides, vicilin-like peptides, and snaking were isolated from plants of the Solanaceae and were involved in their defense mechanism. These peptides exhibited significant antibacterial, antifungal and antiviral activity against organisms for both plant and human host. Brugmansia, Capsicum , Datura , Nicotiana, Salpichora, Solanum , Petunia , and Withania are the most commonly studied genera for AMPs. Among these genera, Capsicum and the Solanum ranked top according to the total number of studies (35%–38% studies) for different AMPs. The mechanisms of action of the reported AMPs from Solanaceae was not any new rather similar to other reported AMPs including alteration of membrane potential and permeability, membrane pore formation, and cell aggregation. Whereas, induction of cell membrane permiabilization, inhibition of germination and alteration of hyphal growth were reported as mechanisms of antifungal activity. Plants of the Solanaceae have been used traditionally as antimicrobial, insecticidal, and antiinfectious agents, and as poisons. The reported AMPs from the Solanaceae are the products of chemical shields to protect plants from microorganisms and pests which unfold an obvious link with their traditional medicinal use. In summary, it is evident that AMPs from this family possess considerable antimicrobial activity against a wide range of bacterial and fungal pathogens and can be regarded as a potential source for lead molecules to develop new antimicrobial agents. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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49. A bibliometric analysis of the top 50 most cited articles published in the Dental Traumatology.
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Ahmad, Paras, Vincent Abbott, Paul, Khursheed Alam, Mohammad, and Ahmed Asif, Jawaad
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CITATION analysis ,BIBLIOGRAPHICAL citations ,TEETH injuries ,TRAUMATOLOGY ,EXPERIMENTAL design ,TOOTH root diseases ,BIBLIOMETRICS - Abstract
Background/aims: The impact of a scientific article in its respective field is reflected by its citation count. The purpose of this review was to conduct a citation analysis in order to identify and analyze the top 50 most cited articles published in Dental Traumatology since its inception in order to highlight the contribution of the journal to the field of Dental Traumatology.Methods: Elsevier's Scopus was used to search and analyze the 50 most frequently cited scientific papers. After the screening process, two reviewers arranged the articles in a descending order based on their citation counts. Each article was then cross-matched with Google Scholar. The articles were analyzed, and information including citation counts, citation density, publication year, authorship, contributing institutions and countries, article topic, study design, and keywords was extracted.Results: The literature search identified 2421 articles. The citation counts of the 50 selected articles varied from 117 to 580 (Scopus) and 206 to 1130 (Google Scholar). The year in which most top 50 articles were published was 2002 (n = 5). Among 105 authors, the greatest contribution was made by JO Andreasen (n = 12). Most of the articles originated from the United States (n = 12) with the greatest contributions from the University Hospital (Rigshospitalet), Copenhagen, Denmark (n = 6). Original research article was the most frequent study design (n = 34). The majority of the top 50 articles were focused on traumatic dental injuries. Among 131 unique key words, root resorption (n = 6) was the most frequently used. A non-significant correlation occurred between citation count (correlation coefficient = 0.127, P = .378), citation density (correlation coefficient = 0.654, P = 2.493), and publication age.Conclusions: This study identified the top 50 most cited articles published in this journal in the specialty of Dental Traumatology. The publication year of an article was not significantly associated with citation count nor citation density. [ABSTRACT FROM AUTHOR]- Published
- 2020
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50. Metasurface-Enabled Antiparallel Dual-Beam Rectangular-Waveguide Antenna.
- Author
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Ahmed, Asif, Robel, Md. Rokunuzzaman, and Rowe, Wayne S. T.
- Abstract
We propose a metasurface (MTS) structure integrated at the aperture of a flanged rectangular waveguide to produce dual-beam radiation. The dual beams are antiparallel in an orientation and perpendicular to the boresight direction. The MTS is backed by a dielectric slab to produce a substrate integrated waveguide-like response above the flange. The MTS is engineered to limit the boresight emission from the waveguide aperture, as well as to allow symmetric wave splitting between the MTS and waveguide flange. A lens-like end texturing involving surface tapering and electromagnetic bandgap cells is utilized to enhance the beam directivity at endfire from the flange. The dual-beam radiation exists for all frequencies between 10.5 and 12.4 GHz. The proposed design is modeled via full-wave simulation in commercial software, then validated through the measurement of a fabricated prototype. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
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