Publications by authors named "Tahir Farooq"

39 Publications

Role of Trichoderma as a biocontrol agent (BCA) of phytoparasitic nematodes and plant growth inducer.

J Invertebr Pathol 2021 Jul 1;183:107626. Epub 2021 Jun 1.

State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China.

Nematodes as plant pathogens adversely affect food, fiber, and biofuels production by causing plant diseases. A variety of chemical nematicides are being applied to soil, seeds, or foliage with a goal of disease prevention. Despite the proven efficacy of these chemicals against plant-parasitic nematodes, factors like prolonged residual toxicity to human health, environmental pollution, and the risk of resistance development can't be neglected. Due to these reasons, many chemicals are being banned continuously or delimited in the crop production system. Alternatively, the need for long-term strategies and integrative approaches to control plant diseases is inevitable. Trichoderma spp. are widely used in agriculture as biological control agents (BCA). To our knowledge, either very little or no information available on the most recent developments regarding Trichoderma-mediated biological control of plant-parasitic nematodes. This review summarizes the recent advances in using Trichoderma as BCA and plant growth regulator with a special focus on plant-parasitic nematodes.
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http://dx.doi.org/10.1016/j.jip.2021.107626DOI Listing
July 2021

COVID-19 and Nanoscience in the Developing World: Rapid Detection and Remediation in Wastewater.

Nanomaterials (Basel) 2021 Apr 12;11(4). Epub 2021 Apr 12.

Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China.

Given the known presence of SARS-Cov-2 in wastewater, stemming disease spread in global regions where untreated effluent in the environment is common will experience additional pressure. Though development and preliminary trials of a vaccine against SARS-CoV-2 have been launched in several countries, rapid and effective alternative tools for the timely detection and remediation of SARS-CoV-2 in wastewater, especially in the developing countries, is of paramount importance. Here, we propose a promising, non-invasive technique for early prediction and targeted detection of SARS-CoV-2 to prevent current and future outbreaks. Thus, a combination of nanotechnology with wastewater-based epidemiology and artificial intelligence could be deployed for community-level wastewater virus detection and remediation.
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http://dx.doi.org/10.3390/nano11040991DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8069490PMC
April 2021

Nanotechnology and Plant Viruses: An Emerging Disease Management Approach for Resistant Pathogens.

ACS Nano 2021 04 24;15(4):6030-6037. Epub 2021 Mar 24.

Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation and College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, P.R. China.

Phytoviruses are highly destructive plant pathogens, causing significant agricultural losses due to their genomic diversity, rapid, and dynamic evolution, and the general inadequacy of management options. Although an increasing number of studies are being published demonstrating the efficacy of engineered nanomaterials to treat a range of plant pathogens, very little work has been done with phytoviruses. Herein, we describe the emerging field of "Nanophytovirology" as a potential management approach to combat plant viral diseases. Because of their special physiochemical properties, nanoparticles (NPs) can interact with viruses, their vectors, and the host plants in a variety of specific and useful ways. We specifically describe the potential mechanisms underlying NPs-plant-virus interactions and explore the antiviral role of NPs. We discuss the limited literature, as well as the challenges and research gaps that are instrumental to the successful development of a nanotechnology-based, multidisciplinary approach for timely detection, treatment, and prevention of viral diseases.
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http://dx.doi.org/10.1021/acsnano.0c10910DOI Listing
April 2021

Laparoscopic Management of Common Bile Duct Stones: Stratifying Risks, a District Hospital Experience.

J Laparoendosc Adv Surg Tech A 2021 Mar 10. Epub 2021 Mar 10.

Yeovil District Hospital NHS Foundation Trust, Higher Kingston, Yeovil, United Kingdom.

Management of bile duct stones is variable. Selection of the appropriate treatment modality based on identifiable risk factors can increase the chances of a successful outcome. The aim of this study is to identify factors affecting outcomes of a laparoscopic bile duct exploration. Retrospective data analysis of consecutive laparoscopic bile duct explorations over a period of 13 years at a district general hospital. The total number of patients in the study was 85. Elective explorations were 56 while 29 were emergency procedures. The mean operative time was 154 minutes. The conversion rate was 14% with failure to extract stones being the most common reason. Forty-two percent of conversions were in nonelective procedures and 17% in previous endoscopic retrograde cholangiopancreatography (ERCP) failures. Eleven percent patients had a transcystic clearance of bile duct and the largest stone removed transcystic was 5 mm. The largest stone removed by a laparoscopic choledochotomy was 15 mm and stones >20 mm were removed on conversion. Seven patients (8%) had a postoperative bile leak, 4 of these required a postoperative ERCP stent and radiological drainage while 3 required a reoperation. Three patients had retained stones treated by postoperative ERCP. Emergency procedures, increasing number and size of stones, previous failed ERCP are factors that contribute to the outcomes of a laparoscopic bile duct exploration. The chances of a successful exploration can be improved by appropriate patient and procedure selection and preparation based on identification of these factors.
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http://dx.doi.org/10.1089/lap.2021.0022DOI Listing
March 2021

Silicon-Mediated Priming Induces Acclimation to Mild Water-Deficit Stress by Altering Physio-Biochemical Attributes in Wheat Plants.

Front Plant Sci 2021 19;12:625541. Epub 2021 Feb 19.

Institute of Molecular Biology and Biotechnology (IMBB), The University of Lahore, Lahore, Pakistan.

Water-deficit stress negatively affects seed germination, seedling development, and plant growth by disrupting cellular and metabolic functions, reducing the productivity and yield of field crops. In this study, sodium silicate (SS) has been employed as a seed priming agent for acclimation to mild water-deficit stress by invoking priming memory in wheat plants. In pot experiments, the SS-primed (20, 40, and 60 mM) and non-primed control seeds were allowed to grow under normal and mild water-deficit conditions. Subsequently, known methods were followed for physiological and biochemical studies using flag leaves of 98-day mature wheat plants. The antioxidant and hydrolytic enzymes were upregulated, while proteins, reducing sugars, total sugars, and glycine betaine increased significantly in the flag leaves of wheat plants originated from SS-treated seeds compared to the control under mild water-deficit stress. Significant decreases in the malondialdehyde (MDA) and proline contents suggested a controlled production of reactive oxygen species, which resulted in enhanced cell membrane stability. The SS priming induced a significant enhancement in yield, plant biomass, and 100-grain weight of wheat plants under water-deficit stress. The improvement in the yield parameters indicated the induction of Si-mediated stress acclimation in SS-primed seeds that elicited water-deficit tolerance until the maturity of plants, ensuring sustainable productivity of climate-smart plants.
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http://dx.doi.org/10.3389/fpls.2021.625541DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7933522PMC
February 2021

Multivariate Investigation of Toxic and Essential Metals in the Serum from Various Types and Stages of Colorectal Cancer Patients.

Biol Trace Elem Res 2021 Feb 26. Epub 2021 Feb 26.

Department of Chemistry, South China University of Technology, Guangzhou, 510641, China.

Colorectal cancer (CRC) is currently one of the most frequent malignant neoplasms, ranking 3rd in incidence and 2nd in mortality both in the USA and across the world. The pathogenesis of CRC is a complex interaction between genetic susceptibility and environmental factors such as exposure to metals. Therefore, the present study was intended to assess the imbalances in the concentrations of selected essential/toxic elements (Pb, Cr, Fe, Zn, As, Cd, Cu, Se, Ni, and Hg) in the serum of newly diagnosed colorectal carcinoma patients (n = 165) in comparison with counterpart controls (n = 151) by atomic absorption spectrometry after wet-acid digestion method. Serum carcinoembryonic antigen (CEA) of the CRC patients was determined using immunoradiometric method. Body mass index (BMI) which is an established risk factor for CRC was also calculated for patients and healthy controls. Conversely, average Ni (2.721 μg/g), Cd (0.563 μg/g), As (0.539 μg/g), and Pb (1.273 μg/g) levels were significantly elevated in the serum of CRC patients compared to the healthy donors, while the average Se (7.052 μg/g), Fe (15.67 μg/g), Cu (2.033 μg/g), and Zn (8.059 μg/g) concentrations were elevated in controls. The correlation coefficients between the elements in the cancerous patients demonstrated significantly dissimilar communal relationships compared with the healthy subjects. Significant differences in the elemental levels were also showed for CRC types (primary colorectal lymphoma, gastrointestinal stromal tumor, and adenocarcinoma) and CRC stages (stage-I, stage-II, stage-III, and stage-IV) among the patients. Majority of the elements demonstrated perceptible disparities in their levels based on dietary, habitat, gender, and smoking habits of the malignant patients and healthy subjects. Multivariate methods revealed noticeably divergent apportionment among the toxic/essential elements in the cancerous patients than the healthy counterparts. Overall, the study showed significantly divergent distribution and associations of the essential and toxic elemental levels in the serum of the CRC patients in comparison with the healthy donors.
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http://dx.doi.org/10.1007/s12011-021-02632-2DOI Listing
February 2021

Sodium nitroprusside mediated priming memory invokes water-deficit stress acclimation in wheat plants through physio-biochemical alterations.

Plant Physiol Biochem 2021 Mar 28;160:329-340. Epub 2021 Jan 28.

Institute of Molecular Biology and Biotechnology (IMBB), University of Lahore, Lahore, Pakistan.

Aim: Water-deficit stress is the most devastating environmental factor that adversely affects plant growth causing yield losses and low crop productivity. In this study, we employed sodium nitroprusside (SNP) as a seed priming agent for the acclimation of water-deficit stress in wheat plants by invoking priming memory.

Methods: The SNP-primed (75, 100, and 125 μM) and non-primed controls were allowed to grow in pots under water deficit and normal conditions. The flag leaves of 98-days mature plants were used for biochemical and physiological studies by following the well-established methods.

Results: The antioxidant and hydrolytic enzymes were upregulated while reducing sugars, total sugars, and glycine betaine increased significantly in flag leaves of wheat plants originated from SNP-treated seeds compared to control under water deficit stress. However, a significant reduction in MDA and proline contents represented a lesser ROS production which resulted in enhanced cell membrane stability. Consequently, there was a significant enhancement in yield, plant biomass and 100 grains weight of wheat plants under water deficit stress.

Conclusion: The improvement in yield parameters indicates the induction of priming memory in SNP-primed seeds which elicit water deficit tolerance till the maturity of plants thus ensures sustainable productivity of wheat.
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http://dx.doi.org/10.1016/j.plaphy.2021.01.037DOI Listing
March 2021

Wave discrimination at C-band frequencies in microstrip structures inspired by electromagnetically induced transparency.

Sci Rep 2021 Feb 3;11(1):2983. Epub 2021 Feb 3.

Research Institute for Microwave and Millimeter-Wave Studies, National University of Sciences and Technology, Islamabad, Pakistan.

We present the design and practical implementation of a microstrip diplexer based on the wave discrimination property associated with the electromagnetically induced transparency (EIT)-like effect. The EIT is a quantum interference phenomenon which happens between two atomic transition pathways and allows wave propagation within a medium's absorption spectrum. Here, we exploit an analogous interference mechanism in a three-port microstrip structure to demonstrate a diplexer based on the EIT-like effect in the microwave regime. Since the transparency is accompanied by a high transmission and strong dispersion characteristics, compact frequency discriminating structures that can resolve nearby frequencies with high isolation can be devised. Our proposed C-band diplexer consists of pairs of unequal open-circuit stubs, which resonate at detuned frequencies and interfere to form the EIT-like passbands for diplexer action. The design is highly compact and scalable in frequency for both PCB and on-chip applications. A prototype of diplexer is fabricated for the center frequencies of lower and upper passbands at 4.6 GHz and 5.5 GHz respectively. The transmission zeros are designed at the complementary channels so that the two passbands are highly isolated presenting the isolation of about 40 dB. The measured insertion loss of lower and upper passband is 0.59 dB and 0.61 dB respectively. Measured input return loss is better than - 15 dB, while the output return losses are well below - 12 dB. Moreover, a decent value of about 200 is achieved for the group refractive index around the EIT-like passbands, which reveals the slow wave characteristics of the proposed EIT-based diplexer.
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http://dx.doi.org/10.1038/s41598-021-82618-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7859401PMC
February 2021

Diamond step-index nanowaveguide to structure light efficiently in near and deep ultraviolet regimes.

Sci Rep 2020 Oct 28;10(1):18502. Epub 2020 Oct 28.

Research Institute for Microwave and Millimeter-Wave Studies (RIMMS), National University of Sciences and Technology (NUST), Islamabad, 46000, Pakistan.

Two-dimensional metamaterials, consisting of an array of ultrathin building blocks, offer a versatile and compact platform for tailoring the properties of the electromagnetic waves. Such flat metasurfaces provide a unique solution to circumvent the limitations imposed by their three-dimensional counterparts. Albeit several successful demonstrations of metasurfaces have been presented in the visible, infrared, and terahertz regimes, etc., there is hardly any demonstration for ultraviolet wavelengths due to the unavailability of the appropriate lossless materials. Here, we present diamond as an ultra-low loss material for the near and deep ultraviolet (UV) light and engineer diamond step-index nanowaveguides (DSINs) to achieve full control over the phase and amplitude of the incident wave. A comprehensive analytical solution of step-index nanowaveguides (supported by the numerical study) is provided to describe the underlying mechanism of such controlled wavefront shaping. Due to the ultra-low loss nature of diamond in near and deep UV regimes, our DSINs and metasurfaces designed (from them) exhibit a decent efficiency of ≈ 84% over the entire spectrum of interest. To verify this high efficiency and absolute control over wavefront, we have designed polarization-insensitive meta-holograms through optimized DSINs for operational wavelength λ = 250 nm.
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http://dx.doi.org/10.1038/s41598-020-75718-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7595241PMC
October 2020

Carbon-based nanomaterials suppress tobacco mosaic virus (TMV) infection and induce resistance in Nicotiana benthamiana.

J Hazard Mater 2021 02 2;404(Pt A):124167. Epub 2020 Oct 2.

Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation and College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, PR China. Electronic address:

Although nanomaterials (NMs) may inhibit viral pathogens, the mechanisms governing plant-virus-nanomaterial interactions remain unknown. Nicotiana benthamiana plants were treated with nanoscale titanium dioxide (TiO) and silver (Ag), C fullerenes, and carbon nanotubes (CNTs) at 100, 200 and 500 mg L for a 21-day foliar exposure before inoculation with GFP-tagged tobacco mosaic virus (TMV). Plants treated with CNTs and C (200 mg L) exhibited normal phenotype and viral symptomology was not evident at 5 days post-infection. TiO and Ag failed to suppress viral infection. RT-qPCR analysis revealed that viral coat protein transcript abundance and GFP mRNA expression were reduced 74-81% upon CNTs and C treatment. TEM revealed that the chloroplast ultrastructure in carbon NM-treated plants was unaffected by TMV infection. Fluorescence measurement of CNTs and C (200 mg L) treated plants indicated photosynthesis equivalent to healthy controls. CNTs and C induced upregulation of the defense-related phytohormones abscisic acid and salicylic acid by 33-52%; the transcription of genes responsible for phytohormone biosynthesis was elevated by 94-104% in treated plants. Our findings demonstrate the protective role of carbon-based NMs, with suppression of TMV symptoms via hindered physical movement and viral replication. Given the lack of viral phytopathogen treatment options, this work represents a novel area of nano-enabled agriculture.
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http://dx.doi.org/10.1016/j.jhazmat.2020.124167DOI Listing
February 2021

Twisted non-diffracting beams through all dielectric meta-axicons.

Nanoscale 2019 Nov 22;11(43):20571-20578. Epub 2019 Oct 22.

Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea. and Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea.

We demonstrate transmission-based all-dielectric, highly efficient (≈73.4%) and polarization-insensitive meta-axicons (for the visible wavelength of 633 nm) to generate zero and higher order Bessel beams without using additional components. The Bessel beams, owing to their diverse applications and non-diffractive properties, attract great interest from the scientific community. It is shown that the propagation length can be increased through a lower numerical aperture (∼2600 λ for NA = 0.1) whereas a higher full width at half maximum (< 0.5 λ) can be obtained for a higher numerical aperture (for NA ≥ 0.7). Our dielectric material, hydrogenated amorphous silicon (a-Si:H), provides a significant efficiency advantage over plasmonic and other high-index all-dielectric (e.g., TiO and GaN) metasurfaces in terms of cost, ease of fabrication, and CMOS compatibility. The finite difference time domain (FDTD) technique based numerically simulated and experimental results show excellent agreement. Due to the technological and scientific importance of the Bessel beams, the recommended material and meta-axicons provide an efficient and compact platform for realizing various advanced applications like optical manipulation, optical alignment, laser fabrication, imaging, and laser machining.
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http://dx.doi.org/10.1039/c9nr04888jDOI Listing
November 2019

Tomato Yellow Leaf Curl China Virus Impairs Photosynthesis in the Infected with βC1 as an Aggravating Factor.

Plant Pathol J 2019 Oct 1;35(5):521-529. Epub 2019 Oct 1.

State Key Laboratory for Plant Disease and Insect Pest, Institute of Plant Protection, China Academy of Agricultural Sciences, Beijing 100193, China.

is a species of the widespread geminiviruses. The infection of by Tomato yellow leaf curl China virus (TYLCCNV) causes a reduction in photosynthetic activity, which is part of the viral symptoms. βC1 is a viral factor encoded by the betasatellite DNA (DNAβ) accompanying TYLCCNV. It is a major viral pathogenicity factor of TYLCCNV. To elucidate the effect of βC1 on plants' photosynthesis, we measured the relative chlorophyll (Chl) content and Chl fluorescence in TYLCCNV-infected and transgenic plants. The results showed that Chl content is reduced in TYLCCNV A-infected, TYLCCNV A plus DNAβ (TYLCCNV A + β)-infected and transgenic plants. Further, changes in Chl fluorescence parameters, such as electron transport rate, / , , and , revealed that photosynthetic efficiency is compromised in the aforementioned plants. The presense of aggravated the decrease of Chl content and photosynthetic efficiency during viral infection. Additionally, the real-time quantitative PCR analysis of oxygen evolving complex genes in photosystem II, such as , , , and , showed a significant reduction of the relative expression of these genes at the late stage of TYLCCNV A + β infection and at the vegetative stage of transgenic plants. In summary, this study revealed the pathogenicity of TYLCCNV in photosynthesis and disclosed the effect of βC1 in exacerbating the damage in photosynthesis efficiency by TYLCCNV infection.
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http://dx.doi.org/10.5423/PPJ.OA.04.2019.0120DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6788413PMC
October 2019

Evaluation of structurally different benzimidazoles as priming agents, plant defence activators and growth enhancers in wheat.

BMC Chem 2019 Dec 11;13(1):29. Epub 2019 Mar 11.

5Department of Chemistry, Government College University, Faisalabad, Pakistan.

Priming is a valuable, facile and well-established technique used to enhance seed quality to achieve rapid germination, establishment of stress resistance and improvement of crop yields. Different natural and synthetic priming agents have been used for better crop performance and abiotic stress management. In this study, four different benzimidazoles were selected as priming agents and their comparative effects were evaluated on different biochemical attributes including total soluble protein, total oxidant status, MDA contents, antioxidant enzymes (SOD, POD) and hydrolytic enzymes (protease, estrases) compared to control. Treatments with 2-thio-1--benzimidazole reduced total soluble proteins and increased total oxidant status significantly but no considerable effect was observed on other parameters. Priming with 2-(4-chlorophenyl)-1--benzimidazole considerably increased the total oxidant status and a little improvement was observed in total soluble proteins. Seeds primed with 1--benzimidazole showed a noticeable decrease in the protease activity while all other priming treatments were unable to induce any detectable change compared to control. The treatment with 2-(4-methoxyphenyl)-1--benzimidazole induced maximum reduction in MDA contents and POD activity. Moreover, all benzimidazole priming treatments reduced mean germination time, increased germination percentage and germination rate of wheat seeds.
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http://dx.doi.org/10.1186/s13065-019-0546-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6661826PMC
December 2019

Outcomes of ocular evisceration and enucleation in the British Armed Forces from Iraq and Afghanistan.

Eye (Lond) 2019 11 5;33(11):1748-1755. Epub 2019 Jun 5.

Scott Health Ltd, Coatbridge, Scotland.

Background/objectives: To evaluate outcomes from all British military patients who underwent eye removal during the Iraq and Afghanistan wars.

Subjects/methods: Retrospective case note review of all patients (n = 19) who had undergone either evisceration or enucleation, on a database of all military patients repatriated to the Royal Centre for Defence Medicine, Birmingham.

Results: Twenty eye removals were performed on 19 patients, of which 14 (70%) were eviscerations and 6 (30%) were enucleations. Orbital wall fractures were seen in 12 (61%) patients, with orbital floor fractures being the most common. The eye removal was a primary procedure in five of fourteen eviscerations, and five of six enucleations. Complications were seen after four (28.6%) eviscerations patients and two (33.3%) enucleations. Postoperative pain was problematic after three (21.4%) eviscerations but no enucleations. Orbital implants were placed during three of the five primary enucleations, with good outcomes in two. One patient however required implant retrieval and wound washout due to a high risk of infection and communication with the intra-cranial space.

Conclusions: Evisceration and enucleation are both viable options in the management of severe ocular trauma in military patients. Evisceration and enucleation have similar complication rates and outcomes, and both have low rates of sympathetic ophthalmia. Primary orbital implants can be at high risk in cases with orbital roof fracture, but can provide good outcomes in select patients.
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http://dx.doi.org/10.1038/s41433-019-0480-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7002516PMC
November 2019

Correction: Polarisation insensitive multifunctional metasurfaces based on all-dielectric nanowaveguides.

Nanoscale 2019 05;11(21):10555

Research Institute for Microwave and Millimeter-wave Studies (RIMMS), National University of Sciences and Technology (NUST), Islamabad 46000, Pakistan.

Correction for 'Polarisation insensitive multifunctional metasurfaces based on all-dielectric nanowaveguides' by Nasir Mahmood et al., Nanoscale, 2018, 10, 18323-18330.
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http://dx.doi.org/10.1039/c9nr90109dDOI Listing
May 2019

Linear and circular-polarization conversion in X-band using anisotropic metasurface.

Sci Rep 2019 Mar 14;9(1):4552. Epub 2019 Mar 14.

Research Institute for Microwave and Millimeter-wave Studies, National University of Sciences and Technology (NUST), Islamabad, Pakistan.

An ultrathin single-layer metasurface manifesting both linear cross-polarization conversion (CPC) and linear-to-circular polarization (LP-to-CP) conversion in X-band is presented in this research. The designed metasurface acts as a multifunctional metasurface achieving CPC over a fractional bandwidth of 31.6% (8-11 GHz) with more than 95% efficiency while linear-to-circular polarization conversion is realized over two frequency bands from 7.5-7.7 GHz and 11.5-11.9 GHz. Moreover, the overall optimized structure of the unit cell results in a stable polarization transformation against changes in the incidence angle up to 45° both for transverse-electric (TE) and transverse-magnetic (TM) polarizations. The proposed metasurface with simple structure, compact size, angular stability and multifunctional capability qualifies for many applications in communication and polarization manipulating devices.
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http://dx.doi.org/10.1038/s41598-019-40793-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6418155PMC
March 2019

Quasi-Crystal Metasurface for Simultaneous Half- and Quarter-Wave Plate Operation.

Sci Rep 2018 Oct 24;8(1):15743. Epub 2018 Oct 24.

Research Institute for Microwave and Millimeter-wave Studies, National University of Sciences and Technology, Islamabad, Pakistan.

We present a quasi-crystal metasurface that can simultaneously work as efficient cross-polarizer and circular polarizer for wide range of frequencies. The quasi-crystal technique benefits from individual resonant response of anisotropic patch and the coupled response due to periodic perturbations in the square lattice. It is shown that quasi-crystals offer broadband response for cross-polarization as well as high efficiency circular-polarization conversion of reflected fields. The quasi-crystal metasurface achieves cross-polarization (above -3 dB) for two broad frequency bands between 10.28-15.50 GHz and 16.21-18.80 GHz. Furthermore, the proposed metasurface can simultaneously work as high efficiency circular-polarizer from 10.15-10.27 GHz and 15.51-16.20 GHz. The metasurface design is also optimized to suppress co-polarization below -10 dB between 10.5-15.5 GHz. This metasurface can find potential applications in reflector antennas, imaging microscopy, remote sensing, and control of radar cross-section etc.
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http://dx.doi.org/10.1038/s41598-018-34142-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6200769PMC
October 2018

Polarisation insensitive multifunctional metasurfaces based on all-dielectric nanowaveguides.

Nanoscale 2018 Oct;10(38):18323-18330

Department of Electrical Engineering, Information Technology University of the Punjab, Lahore 54000, Pakistan.

Metasurfaces, two dimensional (2D) metamaterials comprised of subwavelength features, can be used to tailor the amplitude, phase and polarisation of an incident electromagnetic wave propagating at an interface. Though many novel metasurfaces have been explored, the hunt for cost-effective, highly efficient, low-loss and polarisation insensitive applications is ongoing. In this work, we utilise an efficient and cost-effective dielectric material, hydrogenated amorphous silicon (a-Si:H), to create a ultra-thin transmissive surface that simultaneously controls phase. This material exhibits significantly lower absorption in the visible regime compared to standard amorphous silicon, making it an ideal candidate for various on-chip applications. Our proposed design, which works on the principle of index waveguiding, integrates two distinct phase profiles, that of a lens and of a helical beam, and is versatile due to its polarisation-insensitivity. We show how this metasurface can lead to highly concentrated optical vortices in the visible domain, whose focused ring-shaped profiles carry orbital angular momentum at the miniaturised scale.
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http://dx.doi.org/10.1039/c8nr05633aDOI Listing
October 2018

Enhanced production of Lovastatin by filamentous fungi through solid state fermentation.

Pak J Pharm Sci 2018 Jul;31(4(Supplementary)):1583-1589

Department of Pharmacy, Faculty of Medical and Health Sciences, The University of Poonch, Rawalakot, AJK.

Lovastatin is a natural competitive inhibitor of 3-hydroxy-3-methyl glutaryl coenzyme-A (HMG-CoA) reductase and inhibits specifically rate limiting step in cholesterol biosynthesis. Further, lovastatin in comparison with synthetic drugs has no well-reported side effects. Four pure isolated filamentous fungal strains including Aspergillus niger IBL, Aspergillus terreus FFCBP-1053, Aspergillus flavus PML and Aspergillus nidulans FFCBP-014 have been cultured by solid state fermentation (SSF) using rice straw as substrate for the synthesis of lovastatin. After selecting Aspergillus terreus FFCBP-1053 as the best producer of lovastatin, various selected physical parameters including pH, temperature, inoculums size and moisture content were optimized through response surface methodology (RSM) under center composite design (CCD) for lovastatin hyper production. Maximum lovastatin production of 2070±91.5 was predicted by the quadratic model in the medium having moisture content 70% and pH 4.5 at 35°C which was verified experimentally to be 2140±93.25µg/g DW of FM (microgram/gram dry weight of fermentation medium), significantly (P<0.05) high as compared to un-optimized conditions while it was noted that lovastatin production is independent on inoculum size (P>0.05) measured by spectrophotometer at 245 nm against standard. It was determined that optimized conditions for the hyper-production of lovastatin from fungal sources have a significant effect.
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July 2018

Anti-diabetic activity of aqueous extract of Ipomoea batatas L. in alloxan induced diabetic Wistar rats and its effects on biochemical parameters in diabetic rats.

Pak J Pharm Sci 2018 Jul;31(4(Supplementary)):1539-1548

Department of Pharmacy, Faculty of Medical and Health Sciences, The University of Poonch, Rawalakot, AJK.

Diabetes is a condition where the fasting blood glucose level elevated above the normal range (80-120mg/dL). This increase in blood glucose level may be due to the insulin deficiency i.e. insulin dependent diabetes mellitus (IDDM or type I) or due to insulin resistance i.e. non-insulin dependent diabetes mellitus (NIDDM or type II). Diabetes leads to severe complications in the body even life treating complications e.g. nephropathy, retinopathy, neuropathy increased vascular permeability and delayed wound healing if left untreated. Different drugs are used for the treatment of diabetes mellitus, but synthetic drugs are costly and possess severe side effects. So, more emphasis is being placed on the use of traditional medicines because these sources have fewer side effects than the synthetics drugs and are economical. So the white skinned sweet potato (Ipomoea batatas L.) peel-off was selected for its anti-diabetic effect as well as to see its effects on biochemical parameters. Both young (3-4 months) and old (up to 1 year) Wistar rats were selected for current study. It was found that the aqueous extract of WSSP peel-off had shown beneficial effects. In addition to the decrease in blood glucose level it also decreased protein glycation level total cholesterol, triglycerides, and LDL-cholesterol. Increase in HDL-cholesterol was also observed after treating the rats with aqueous extract of Ipomoea batatas. Additionally, WSSP peel-off had also shown positive results on total protein concentration, albumin, globulin, and plasma enzymes (SGOT and SGPT). Further research would be needed in order to purify the anti-diabetic components and it should be available in compact dose form for all diabetic patients.
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July 2018

Stem Cell Therapy and Type 1 Diabetes Mellitus: Treatment Strategies and Future Perspectives.

Adv Exp Med Biol 2019 ;1084:95-107

Department of Pharmaceutical Chemistry, Government College University, Faisalabad, Pakistan.

Type 1 diabetes mellitus (T1DM) is classified as an autoimmune disease which progressively results in the depletion of insulin-secreting β-cells. Consequently, the insulin secretion stops leading to hyperglycemic situations within the body. Under severe conditions, it also causes multi-organ diabetes-associated dysfunctionalities notably hypercoagulability, neuropathy, nephropathy, retinopathy, and sometimes organ failures. The prevalence of this disease has been noticed about 3% that has highlighted the serious concerns for healthcare professionals around the globe. For the treatment of this disease, the cell therapy is considered as an important therapeutic approach for the replacement of damaged β-cells. However, the development of autoantibodies unfortunately reduces their effectiveness with the passage of time and finally with the recurrence of diabetes mellitus. The development of new techniques for extraction and transplantation of islets failed to support this approach due to the issues related to major surgery and lifelong dependence on immunosuppression. For T1DM, such cells are supposed to produce, store, and supply insulin to maintain glucose homeostasis. The urgent need of much-anticipated substitute for insulin-secreting β-cells directed the researchers to focus on stem cells (SCs) to produce insulin-secreting β-cells. For being more specific and targeted therapeutic approaches, SC-based strategies opened up the new horizons to cure T1DM. This cell-based therapy aimed to produce functional insulin-secreting β-cells to cure diabetes on forever basis. The intrinsic regenerative potential along with immunomodulatory abilities of SCs highlights the therapeutic potential of SC-based strategies. In this article, we have comprehensively highlighted the role of SCs to treat diabetes mellitus.
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http://dx.doi.org/10.1007/5584_2018_195DOI Listing
September 2019

Author Correction: Simultaneous quarter-wave plate and half-mirror operation through a highly flexible single layer anisotropic metasurface.

Sci Rep 2018 Jun 7;8(1):8994. Epub 2018 Jun 7.

Research Institute for Microwave and Millimeter-wave Studies, National University of Sciences and Technology (NUST), Islamabad, Pakistan.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.
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http://dx.doi.org/10.1038/s41598-018-27269-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5990541PMC
June 2018

Investigations of Phytochemical Constituents and Their Pharmacological Properties Isolated from the Genus Urtica: Critical Review and Analysis.

Crit Rev Eukaryot Gene Expr 2018 ;28(1):25-66

Department of Pharmaceutical Chemistry, Government College University, Faisalabad, Pakistan.

The genus Urtica belongs to the family Urticaceae. The plants of this genus are known as nettles or, quite often, as stinging nettles. These plants can be easily identified by the presence of stinging hairs. Urtica species have previously been used for various medicinal purposes. The history for the use of these plants for medicinal purposes starts from the Bronze Age (3000-2000 BC). Medicinally, the genus Urtica has been used to treat several disorders, such as cancer, rheumatoid arthritis, bronchitis, diarrhea, sprains, kidney stones, urinary tract infection, high blood pressure, hemorrhoids, flu, cough, fever, and ulcers. Scientific reports on the phytochemical analysis of this genus has so far revealed more than 123 compounds from this genus, including terpenoids, flavonoids, lignans, sterols, and polyphenols, have been isolated. Various biological activities have been exhibited by these compounds, such as antihypertensive, hepatoprotective, nephroprotective, antiurolithiatic, anthelmintic, diuretic, antinoceceptive, antidiabetic, antiviral, , and immunomodulatory. In this article, we mainly emphasize the phytochemical composition, therapeutic applications, and ethnopharmacological values of various species of genus Urtica.
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http://dx.doi.org/10.1615/CritRevEukaryotGeneExpr.2018020389DOI Listing
July 2019

Synthesis of antibacterial poly(o-chloroaniline)/chromium hybrid composites with enhanced electrical conductivity.

Chem Cent J 2018 Apr 26;12(1):46. Epub 2018 Apr 26.

Department of Information Technology and Electronics, Zhejiang University, Hangzhou, 310027, China.

Electrically conductive polyorthochloroaniline/chromium nanocomposites (POC/Cr NCs) were prepared by in situ chemical oxidative polymerization of orthochloroaniline in the presence of Cr nanoparticles (Cr NPs). The load percentage of Cr nanofiller was varied in POC matrix to investigate the effect of Cr nanoparticles on the properties of the nanocomposites. The composition, structure, and morphology of POC and its composites were examined by Scanning electron microscopy, Fourier transform infrared spectroscopy, and UV-visible spectroscopic analysis. The antibacterial potential of POC and its composites was evaluated by the disc diffusion method against Escherichia coli and Bacillus subtilis. The results showed the improved antibacterial potential with the increase in the load percentage of nanofiller. The electrical conductivity of polymer and its composites was measured and correlated with the load percentage. The results showed that electrical conductivity of the composites was enhanced with the increase in load percentage of Cr nanoparticles.
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http://dx.doi.org/10.1186/s13065-018-0416-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5919894PMC
April 2018

Current status and future possibilities of molecular genetics techniques in Brassica napus.

Biotechnol Lett 2018 Mar 17;40(3):479-492. Epub 2018 Jan 17.

Department of Agriculture, The University of Swabi, Khyber Pakhtunkhwa, Pakistan.

As PCR methods have improved over the last 15 years, there has been an upsurge in the number of new DNA marker tools, which has allowed the generation of high-density molecular maps for all the key Brassica crop types. Biotechnology and molecular plant breeding have emerged as a significant tool for molecular understanding that led to a significant crop improvement in the Brassica napus species. Brassica napus possess a very complicated polyploidy-based genomics. The quantitative trait locus (QTL) is not sufficient to develop effective markers for trait introgression. In the coming years, the molecular marker techniques will be more effective to determine the whole genome impairing desired traits. Available genetic markers using the single-nucleotide sequence (SNP) technique and high-throughput sequencing are effective in determining the maps and genome polymorphisms amongst candidate genes and allele interactions. High-throughput sequencing and gene mapping techniques are involved in discovering new alleles and gene pairs, serving as a bridge between the gene map and genome evaluation. The decreasing cost for DNA sequencing will help in discovering full genome sequences with less resources and time. This review describes (1) the current use of integrated approaches, such as molecular marker technologies, to determine genome arrangements and interspecific outcomes combined with cost-effective genomes to increase the efficiency in prognostic breeding efforts. (2) It also focused on functional genomics, proteomics and field-based breeding practices to achieve insight into the genetics underlying both simple and complex traits in canola.
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http://dx.doi.org/10.1007/s10529-018-2510-yDOI Listing
March 2018

Emerging Trends in Non-Interferon-Based Genotype-Specific Antiviral Agents: Pharmaceutical Perspectives.

Crit Rev Eukaryot Gene Expr 2017 ;27(4):305-319

Department of Pharmaceutical Chemistry, Government College University, Faisalabad, Pakistan.

Hepatitis C virus (HCV) presents a serious global health threat. Initially, the health-care community mainly focused on interferon (IFN)-based therapeutic options to eradicate HCV, but with the passage of time, these applications became unsuitable due to some serious side effects related to the use of IFN. In recent years, research conducted on different phases of HCV's life cycle has opened a new gateway for the use of a direct-acting new generation of anti-HCV agents. Their safer and ultrarapid response has made possible the introduction of triple therapy and use of IFN-free therapeutic treatment strategies. However, the high cost of these successful therapies has raised serious concerns, particularly in low-income countries, and this has forced pharmaceutical scientists to explore more cost-effective IFN-free alternatives for the treatment of HCV. In this article, we have briefly summarized the latest data regarding the research and development of non-IFN-based antiviral agents. The studies mentioned in this article highlight the significance of non-IFN-based direct-acting antiviral (DAA) agents. Economical alternative anti-HCV agents are expected to become available in the near future for better and more cost-effective treatments of HCV.
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http://dx.doi.org/10.1615/CritRevEukaryotGeneExpr.2017019956DOI Listing
April 2019

Simultaneous quarter-wave plate and half-mirror operation through a highly flexible single layer anisotropic metasurface.

Sci Rep 2017 11 22;7(1):16059. Epub 2017 Nov 22.

Research Institute for Microwave and Millimeter-wave Studies, National University of Sciences and Technology (NUST), Islamabad, Pakistan.

A highly flexible single-layer metasurface manifesting quarter-wave plate as well as half-mirror (1:1 beam-splitter) operation in the microwave frequency regime is being presented in this research. The designed metasurface reflects half power of the impinging linearly polarized electromagnetic wave as circularly polarized wave while the remaining half power is transmitted as circularly polarized wave at resonance frequency. Similarly, a circularly polarized incident wave is reflected and transmitted as linearly polarized wave with equal half powers. Moreover, the response of the metasurface is quite stable against the variations in the incidence angle up to 45°. The measurements performed on the fabricated prototype exhibit a good agreement with the simulation results. The compact size, flexible structure, angular stability and two in one operation (operating as a quarter-wave plate and beam-splitter at the same time) are the main characteristics of the subject metasurface that makes it a potential candidate for numerous applications in communication and miniaturized and conformal polarization control devices.
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http://dx.doi.org/10.1038/s41598-017-15279-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5700169PMC
November 2017

Facile and Green Synthesis of Saturated Cyclic Amines.

Molecules 2017 Oct 12;22(10). Epub 2017 Oct 12.

Department of Applied Chemistry, Government College University, Faisalabad 38900, Pakistan.

Single-nitrogen containing saturated cyclic amines are an important part of both natural and synthetic bioactive compounds. A number of methodologies have been developed for the synthesis of aziridines, azetidines, pyrrolidines, piperidines, azepanes and azocanes. This review highlights some facile and green synthetic routes for the synthesis of unsubstituted, multisubstituted and highly functionalized saturated cyclic amines including one-pot, microwave assisted, metal-free, solvent-free and in aqueous media.
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http://dx.doi.org/10.3390/molecules22101691DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6151670PMC
October 2017

Ethnopharmacological Investigations of Phytochemical Constituents Isolated from the Genus Cuscuta.

Crit Rev Eukaryot Gene Expr 2017 ;27(2):113-150

Department of Pharmaceutical Chemistry, Government College University, Faisalabad, Pakistan.

The genus Cuscuta, of the family Cuscutaceae, is present in plants and has been traditionally used medicinally against many diseases and conditions, notably depression, mental illness, headache, spleen disease, jaundice, diabetes mellitus, and hypertension. Large numbers of phytochemical constituents such as alkaloids, flavonoids, lignins, oxygen heterocyclic compounds, steroids, fatty acids, phenolic acids, resin glycosides, and polysaccharides have been isolated from different species of Cuscuta. Ethnopharmacological studies conducted on such constituents have also been shown Cuscuta to possess anticancer, antiviral, antispasmodic, antihypertensive, anticonvulsant, antibacterial, antioxidant, diuretic, and hair-growth activity. Many tribes and traditional communities have long used the different forms of Cuscuta for treatment and prevention of many diseases. In this article, we comprehensively summarize relevant data regarding the phytochemical, ethnopharmacological, and traditional therapeutic uses of Cuscuta. In addition, we review the parts of the plants that are used as traditional therapeutic agents, their regions of existence, and their possible modes of action. To conclude, we provide evidence and new insights for further discovery and development of natural drugs from Cuscuta. We show that further studies are needed to investigate the mechanism of action and safety profile of phytochemical constituents isolated from Cuscuta.
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http://dx.doi.org/10.1615/CritRevEukaryotGeneExpr.2017019193DOI Listing
September 2017

Disposable, Paper-Based, Inkjet-Printed Humidity and H₂S Gas Sensor for Passive Sensing Applications.

Sensors (Basel) 2016 Dec 6;16(12). Epub 2016 Dec 6.

Research Institute for Microwave and Millimeterwave Studies (RIMMS), National University of Sciences and Technology (NUST), Islamabad 44000, Pakistan.

An inkjet-printed, fully passive sensor capable of either humidity or gas sensing is presented herein. The sensor is composed of an interdigitated electrode, a customized printable gas sensitive ink and a specialized dipole antenna for wireless sensing. The interdigitated electrode printed on a paper substrate provides the base conductivity that varies during the sensing process. Aided by the porous nature of the substrate, a change in relative humidity from 18% to 88% decreases the electrode resistance from a few Mega-ohms to the kilo-ohm range. For gas sensing, an additional copper acetate-based customized ink is printed on top of the electrode, which, upon reaction with hydrogen sulphide gas (H₂S) changes, both the optical and the electrical properties of the electrode. A fast response time of 3 min is achieved at room temperature for a H₂S concentration of 10 ppm at a relative humidity (RH) of 45%. The passive wireless sensing is enabled through an antenna in which the inner loop takes care of conductivity changes in the 4-5 GHz band, whereas the outer-dipole arm is used for chipless identification in the 2-3 GHz band.
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http://dx.doi.org/10.3390/s16122073DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5191054PMC
December 2016