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1.
RSC Adv ; 14(38): 27831-27842, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39234527

RESUMEN

In this study, a simple in situ technique followed by hydrothermal method is used to synthesize a novel tremella-like structure of ZIF-67Co(OH)F@Co3O4/CC metal-organic framework (MOF) derived from zeolite imidazole. The in situ synthesis of metal-organic frameworks (MOFs) increases their conductivity and produces more active sites for ion insertion. Their unique, scalable design not only provides more space to accommodate volume change but also facilitates electrolyte penetration into the electrode resulting in more active materials being utilized and ion-electron transfer occurring faster during the cycle. As a result, the binder-free ZIF-67Co(OH)F@Co3O4/CC supercapacitor electrode exhibits typical pseudo-capacitance behaviour, with a specific capacitance of 442 F g-1 and excellent long-term cycling stability of 90% after 5000 cycles at 10 A g-1.

2.
RSC Adv ; 14(36): 26556-26567, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39175682

RESUMEN

To achieve efficient and cost-effective electrochemical water splitting, highly active and affordable nanostructured catalysts are the key requirement. The current study presents the investigations of the efficacy of metal (Mn, Fe and Ni)-doped Co(OH)2 nanofibers towards oxygen evolution via water splitting. Notably, Ni-doped Co(OH)2 demonstrates superior OER performance in KOH electrolyte, surpassing standard IrO2 with a modest potential of 1.62 V at 10 mA cm-2. The remarkable activity is attributed to the nanofiber structure, facilitating faster conduction and offering readily available active sites. Ni-doped Co(OH)2 nanofibers displayed enduring stability even after 1000 cycles. This work underscores the importance of transition-metal based catalysts as effective electrocatalysts, providing the groundwork for the development of cutting-edge catalysts. Additionally, the electrochemical sensing capability towards ascorbic acid is evaluated, with Ni-doped Co(OH)2 showing the most promising response, characterized by the lowest LOD and LOQ values. These findings highlight the potential of Ni-doped Co(OH)2 nanofibers for upcoming diagnostic detection devices.

4.
J Coll Physicians Surg Pak ; 34(8): 985-988, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39113521

RESUMEN

OBJECTIVE: To evaluate presentations, aetiologies, interventions, and outcomes of patients presenting with acute limb ischaemia (ALI). STUDY DESIGN: An observational study. Place and Duration of the Study: Department of Surgery, The Aga Khan University Hospital, Karachi, Pakistan, from January 2000 to December 2020. METHODOLOGY: Record of 104 patients who underwent surgical interventions for ALI was retrospectively evaluated. The diagnosis was confirmed on imaging (ultrasound / CTA / conventional angiography). Demographic characteristics, co-morbidities, aetiologies, and outcomes were analysed using descriptive statistics and logistic regression. RESULTS: The cohort's mean age was 58.89 ± 12.6 years, with (54.8%, n = 57) females and (45.2%, n = 47) males. Hypertension (54.8%, n = 57), diabetes (46.2%, n = 48), and atrial fibrillation (34.6%, n = 36) were common comorbidities. Thromboembolism (67.3%, n = 70) and thrombotic occlusion (32.7%, n = 34) were primary aetiologies, predominantly affecting the lower limb (66.3%, n = 58) and femoral artery (51.9%, n = 54). The majority of cases were classified as Rutherford classification 2A (53.8%; 56 cases) and 2B (44.2%; 46 cases); 58 (55.8%) patients were classified as ASA Class III, while 36 (34.6%) patients were categorised as ASA Class IV. Embolectomy (80.8%, n = 84) was the prevailing intervention, with an amputation rate (17.3%, n = 18) and a mortality rate (5.8%, n = 6). CONCLUSION: Most patients with ALI presented with Rutherford Class II and had thromboembolism aetiology. Embolectomy was the most commonly performed procedure with a high amputation rate and mortality. KEY WORDS: Acute limb ischaemia, Embolectomy, Amputation, Thromboembolism.


Asunto(s)
Amputación Quirúrgica , Isquemia , Humanos , Femenino , Masculino , Persona de Mediana Edad , Isquemia/cirugía , Estudios Retrospectivos , Pakistán/epidemiología , Anciano , Enfermedad Aguda , Amputación Quirúrgica/estadística & datos numéricos , Extremidad Inferior/irrigación sanguínea , Extremidad Inferior/cirugía , Embolectomía/métodos , Recuperación del Miembro/métodos , Adulto
5.
J Coll Physicians Surg Pak ; 34(7): 817-821, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38978247

RESUMEN

OBJECTIVE: To determine the frequency and pattern of different aetiologies of leg pain among patients visiting vascular surgery clinics. STUDY DESIGN: Cross-sectional study. Place and Duration of the Study: Vascular Surgery Clinics of the Aga Khan University Hospital, Karachi, Pakistan, between February 2021 and June 2023. METHODOLOGY: This study examined patients presenting with leg pain for the first time at vascular surgery clinics. The socio-demographic and clinical data including the clinical symptoms, physical examination findings, and management of leg pain were noted using a specially designed proforma. RESULTS: In a total of 142 patients (200 limbs), 82 (57.7%) were females and 60 (42.3%) were males, with a mean age of 46.8 ± 15.1 years. The patients' mean body mass index (BMI) was 30.2 ± 7.9 kg/m2. Ninety-one (64.1%) patients had a predominantly standing job compared to 51 (35.9%) patients who had a predominantly sitting job. The most common aetiology of leg pain was chronic venous insufficiency (CVI), diagnosed in 107 (53.5%) patients, followed by neurogenic pain [41 (20.5%)], musculoskeletal pain including knee osteoarthritis [30 (15.0%)], and arterial insufficiency [22 (11.0%)].  Conclusion: CVI followed by neuropathic pain was the leading cause of leg pain in vascular surgery clinics at a tertiary care hospital. KEY WORDS: Chronic venous insufficiency, Arterial insufficiency, Vascular surgery, Leg pain, Musculoskeletal pain, Neuralgia.


Asunto(s)
Pierna , Humanos , Femenino , Masculino , Persona de Mediana Edad , Estudios Transversales , Pakistán/epidemiología , Adulto , Pierna/irrigación sanguínea , Procedimientos Quirúrgicos Vasculares , Dolor/etiología , Dolor/epidemiología , Neuralgia/etiología , Neuralgia/epidemiología , Anciano , Dolor Musculoesquelético/epidemiología , Dolor Musculoesquelético/etiología
6.
Biomolecules ; 14(6)2024 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-38927114

RESUMEN

Incidences of drug-resistant tuberculosis have become common and are rising at an alarming rate. Aminoacyl t-RNA synthetase has been validated as a newer target against Mycobacterium tuberculosis. Leucyl t-RNA synthetase (LeuRS) is ubiquitously found in all organisms and regulates transcription, protein synthesis, mitochondrial RNA cleavage, and proofreading of matured t-RNA. Leucyl t-RNA synthetase promotes growth and development and is the key enzyme needed for biofilm formation in Mycobacterium. Inhibition of this enzyme could restrict the growth and development of the mycobacterial population. A database consisting of 2734 drug-like molecules was screened against leucyl t-RNA synthetase enzymes through virtual screening. Based on the docking scores and MMGBSA energy values, the top three compounds were selected for molecular dynamics simulation. The druggable nature of the top three hits was confirmed by predicting their pharmacokinetic parameters. The top three hits-compounds 1035 (ZINC000001543916), 1054 (ZINC000001554197), and 2077 (ZINC000008214483)-were evaluated for their binding affinity toward leucyl t-RNA synthetase by an isothermal titration calorimetry study. The inhibitory activity of these compounds was tested against antimycobacterial activity, biofilm formation, and LeuRS gene expression potential. Compound 1054 (Macimorelin) was found to be the most potent molecule, with better antimycobacterial activity, enzyme binding affinity, and significant inhibition of biofilm formation, as well as inhibition of the LeuRS gene expression. Compound 1054, the top hit compound, has the potential to be used as a lead to develop successful leucyl t-RNA synthetase inhibitors.


Asunto(s)
Antituberculosos , Inhibidores Enzimáticos , Leucina-ARNt Ligasa , Simulación del Acoplamiento Molecular , Mycobacterium tuberculosis , Mycobacterium tuberculosis/enzimología , Mycobacterium tuberculosis/efectos de los fármacos , Ligandos , Antituberculosos/farmacología , Antituberculosos/química , Leucina-ARNt Ligasa/antagonistas & inhibidores , Leucina-ARNt Ligasa/metabolismo , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Calorimetría , Simulación de Dinámica Molecular , Tuberculosis/tratamiento farmacológico , Tuberculosis/microbiología , Simulación por Computador , Unión Proteica , Humanos
7.
Mol Cells ; 47(6): 100068, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38759887

RESUMEN

The coordinated movement of germ layer progenitor cells reaches its peak at the dorsal side, where the Bmp signaling gradient is low, and minimum at the ventral side, where the Bmp gradient is high. This dynamic cell movement is regulated by the interplay of various signaling pathways. The noncanonical Wnt signaling cascade serves as a pivotal regulator of convergence and extension cell movement, facilitated by the activation of small GTPases such as Rho, Rab, and Rac. However, the underlying cause of limited cell movement at the ventral side remains elusive. To explore the functional role of a key regulator in constraining gastrulation cell movement at the ventral side, we investigated the Bmp4-direct target gene, sizzled (szl), to assess its potential role in inhibiting noncanonical Wnt signaling. In our current study, we demonstrated that ectopic expression of szl led to gastrulation defects in a dose-dependent manner without altering cell fate specification. Overexpression of szl resulted in decreased elongation of Activin-treated animal cap and Keller explants. Furthermore, our immunoprecipitation assay unveiled the physical interaction of Szl with noncanonical Wnt ligand proteins (Wnt5 and Wnt11). Additionally, the activation of small GTPases involved in Wnt signaling mediation (RhoA and Rac1) was diminished upon szl overexpression. In summary, our findings suggest that Bmp4 signaling negatively modulates cell movement from the ventral side of the embryo by inducing szl expression during early Xenopus gastrulation.


Asunto(s)
Proteína Morfogenética Ósea 4 , Movimiento Celular , Gastrulación , Proteínas de Xenopus , Xenopus laevis , Animales , Proteína Morfogenética Ósea 4/metabolismo , Ligandos , Proteínas Wnt/metabolismo , Vía de Señalización Wnt , Xenopus laevis/embriología , Xenopus laevis/metabolismo , Proteínas de Xenopus/metabolismo , Proteínas de Xenopus/genética
8.
Environ Sci Pollut Res Int ; 31(24): 34881-34895, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38714613

RESUMEN

The structural, mechanical, vibrational, electronic, optical, SLME, thermoelectric, and thermodynamic properties of X2GaAgCl6 (X = Cs, Rb), a double perovskite material, were computed by employing Density Functional Theory (DFT). CASTEP and Quantum ESPRESSO were used to perform first-principles calculations. X2GaAgCl6 possesses a cubic structure with the space-group symmetry Fm-3 m. The lattice parameters of Cs2GaAgCl6 and Rb2GaAgCl6 were optimized using the energy-volume curves, resulting in values of 7.357 Å and 7.365 Å, respectively. The population analysis confirmed the charge transfer among transition metals and halogen atoms. The stability of crystal X2GaAgCl6 (X = Cs, Rb) is effectively demonstrated by analyzing phonon dispersion curves with no negative frequencies. The band structure calculations indicated the semiconducting nature of compounds with energy gaps of 0.96 eV and 0.88 eV for Cs2GaAgCl6 and Rb2GaAgCl6, respectively. The optical characteristics results confirm that the examined materials are suitable for devices working, primarily in the electromagnetic spectrum's visible region. SLME results showed that Cs2GaAgCl6 has 30% and Rb2GaAgCl6 has 27% efficiency, respectively, suggesting their use in photovoltaics. The thermoelectric properties of X2GaAgCl6 (X = Cs, Rb) were calculated by using the BoltzTraP code in the temperature range of 300 to 800 K. The quasi-harmonic Debye model was applied to calculate the thermodynamic characteristics.


Asunto(s)
Compuestos de Calcio , Energía Solar , Termodinámica , Titanio , Titanio/química , Compuestos de Calcio/química , Óxidos/química
9.
J Pak Med Assoc ; 74(4 (Supple-4)): S170-S174, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38712428

RESUMEN

This study focuses on the current applications, potential, and challenges to Artificial Intelligence (AI) integration in vascular surgery with specific emphasis on its relevance in Pakistan. Despite the benefits of AI in vascular surgery, there is a substantial gap in its adoption in Pakistan compared to global standards. In our context with limited resources and a scarcity of vascular surgeons, AI can serve as a promising solution. It can enhance healthcare accessibility, improve diagnostic accuracy, and alleviate the workload on vascular surgeons. However, hurdles including the absence of a comprehensive vascular surgery database, a shortage of AI experts, and potential algorithmic biases pose significant challenges to AI implementation. Despite these obstacles, the study underscores the imperative for continued research, collaborative efforts, and investments to unlock the full potential of AI and elevate vascular healthcare standards in Pakistan.


Asunto(s)
Inteligencia Artificial , Procedimientos Quirúrgicos Vasculares , Pakistán , Humanos , Procedimientos Quirúrgicos Vasculares/métodos
10.
Arch Microbiol ; 206(4): 149, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38466437

RESUMEN

Domestic yak (Bos grunniens) is an economically important feature of the mountainous region of Gilgit-Baltistan in Pakistan where agriculture is restricted and yaks play multiple roles which includes being a source of milk, meat, hides, fuel and power. However little is known about the parasitic infections in Pakistani yaks. Aim of this research was to report the prevalence and genetic diversity of protozoa parasite (Theileria ovis, 18 S rDNA gene was targeted) and an obligate bacterium (Anaplasma marginale, msp-1 gene was amplified) in the blood that was sampled from 202 yaks collected from four districts in Gilgit-Baltistan during January 2023 till January 2024. Results revealed that 6/202 (3%) yaks were of Theileria ovis while 8/202 (4%) were Anaplasma marginale infected. Positive PCR products of both parasites were confirmed by DNA sequencing and their similarity with previously available pathogen sequences was determined by BLAST analysis. Phylogenetic tree indicated that isolates of both parasites displayed genetic. Anaplasma marginale infection varied with the sampling districts and Shigar district had the highest rate of bacterial infection. Cows were significantly more prone to Theileria ovis infection than bulls. Calf and hybrid yaks were more prone to Anaplasma marginale infection. In conclusion, this is the first report that yaks residing the Gilgit-Baltistan region in Pakistan are infected with Theileria ovis and Anaplasma marginale. Similar larger scales studies are recommended in various regions of Gilgit-Baltistan to document the infection rates of these parasites to formulate strategies that will lead to the effective control of these pathogens.


Asunto(s)
Anaplasma marginale , Anaplasmosis , Theileria , Garrapatas , Femenino , Bovinos , Animales , Ovinos , Anaplasma marginale/genética , Theileria/genética , Pakistán/epidemiología , Anaplasma/genética , Prevalencia , Garrapatas/microbiología , Garrapatas/parasitología , Filogenia , Anaplasmosis/epidemiología , Anaplasmosis/microbiología
11.
J Biomol Struct Dyn ; : 1-21, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38385444

RESUMEN

Programmed cell death ligand 1 (PD-L1) is a crucial target for cancer therapy. Here, an in silico study investigates PD-L1 to inhibit its interaction with PD1, thereby promoting an immune response to eliminate cancer cells. The study employed machine learning (ML) -based QSAR to detect PDL1 inhibitors. Morgan's fingerprint with docking score showed a 0.83 correlation with the experimental IC50, enabling the screening of 3200 natural compounds. The top three compounds, considered 2819, 2821 and 3188, were selected from the ML-based QSAR and subjected to molecular docking and simulation. The binding scores for 2819, 2821 and 3188 were -7.0, -9.0 and -8.9 kcal/mol, respectively. The stability of the ligands during a 100 ns simulation was assessed using RMSD, showing that 2819 and 2821 maintained stable patterns comparable to the control inhibitor. Notably, 2819 exhibited a consistent stable pattern throughout the simulation, while 2821 showed stability in the last 40 ns. The control compound showed the highest number of hydrogen bonds with proteins, whereas compounds 2819 and 2821 formed continuous H-bonds. 3188 was separated from the protein in later phases and is not regarded as a potential PD-L1-binding molecule. MMGBSA binding free energy for complexes was computed. Control had the lowest binding free energy, while 2819 and 2821 also had lower binding energies. In contrast, 3188 showed poor binding free energy, causing protein separation. Principal component analysis showed a loss of entropy and reduced protein conformational variation. Overall, 2819 and 2821 are potential binders for PD-L1 inhibition and immune response triggering.Communicated by Ramaswamy H. Sarma.

12.
J Biomol Struct Dyn ; : 1-18, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38407246

RESUMEN

One of the viral diseases that affect millions of people around the world, particularly in developing countries, is Japanese encephalitis (JE). In this study, the conserved protein of this virus, that is, non-structural protein 5 (NS5), was used as a target protein for this study, and a compound library of 749 antiviral molecules was screened against NS5. The current study employed machine learning-based virtual screening combined with molecular docking. Here, three hits (24360, 123519051 and 213039) had lower binding energies (< -8 kcal/mol) than the control, S-Adenosyl-L-homocysteine (SAH). All the compounds showed significant H-bond interactions with functional residues, which were also observed by the control. Molecular dynamics simulation, MM/GBSA for binding free energy analysis, principal component analysis and free energy landscape were also performed to study the stability of the complex formation. All three compounds had similar root mean square deviation trends, which were comparable to the control, SAH. Post-MD, the 123519051-receptor complex had the highest number of H-bonds (4 to 5) after the control, out of which three exhibited the highest percentage occupancy (50%, 24% and 79%). Both docking and MD, 123519051 showed an H-bond with the residue Gly111, which was also found for the control-protein complex. 123519051 showed the lowest binding free energy with ΔGbind of -89 kJ/mol. Steered molecular dynamics depicted that 123519051 had the maximum magnitude of dissociation (1436.43 kJ/mol/nm), which was more than the control, validating its stable complex formation. This study concluded that 123519051 is a binder and could inhibit the protein NS5 of JE.Communicated by Ramaswamy H. Sarma.

13.
Cells ; 13(3)2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38334616

RESUMEN

Fundamental functions of the intestinal epithelium include the digestion of food, absorption of nutrients, and its ability to act as the first barrier against intruding microbes. Campylobacter jejuni is a major zoonotic pathogen accounting for a substantial portion of bacterial foodborne illnesses. The germ colonizes the intestines of birds and is mainly transmitted to humans through the consumption of contaminated poultry meat. In the human gastrointestinal tract, the bacterium triggers campylobacteriosis that can progress to serious secondary disorders, including reactive arthritis, inflammatory bowel disease and Guillain-Barré syndrome. We recently discovered that C. jejuni serine protease HtrA disrupts intestinal epithelial barrier functions via cleavage of the tight and adherens junction components occludin, claudin-8 and E-cadherin. However, it is unknown whether epithelial damage is mediated by the secreted soluble enzyme, by HtrA contained in shed outer-membrane vesicles (OMVs) or by another mechanism that has yet to be identified. In the present study, we investigated whether soluble recombinant HtrA and/or purified OMVs induce junctional damage to polarized intestinal epithelial cells compared to live C. jejuni bacteria. By using electron and confocal immunofluorescence microscopy, we show that HtrA-expressing C. jejuni bacteria trigger efficient junctional cell damage, but not soluble purified HtrA or HtrA-containing OMVs, not even at high concentrations far exceeding physiological levels. Instead, we found that only bacteria with active protein biosynthesis effectively cleave junctional proteins, which is followed by paracellular transmigration of C. jejuni through the epithelial cell layer. These findings shed new light on the pathogenic activities of HtrA and virulence strategies of C. jejuni.


Asunto(s)
Campylobacter jejuni , Humanos , Campylobacter jejuni/metabolismo , Serina Proteasas/metabolismo , Serina Endopeptidasas/metabolismo , Bacterias/metabolismo , Células Epiteliales/metabolismo , Uniones Intercelulares/metabolismo
14.
J Coll Physicians Surg Pak ; 34(1): 105-108, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38185971

RESUMEN

OBJECTIVE: To evaluate the presentations, aetiologies, and outcomes (survival and morbidity) of patients who underwent abdominal aortic aneurysm (AAA) repair at a tertiary care centre in a low middle-income country (LMIC). STUDY DESIGN: Case-series study. Place and Duration of the Study: Section of Vascular Surgery, Department of Surgery, The Aga Khan University Hospital, Karachi, Pakistan, from January 2000 till April 2022. METHODOLOGY: All patients who underwent elective open repair for AAA were identified using ICD coding 10. Patients' demographics, presentations, treatment options, and outcomes were recorded on a specially designed proforma. Outcomes were measured in terms of 30-day survival and perioperative complications. RESULTS: Forty-two patients were included in the study. Thirty-nine (92.9%) of them were males. The mean age was 63.8 + 12.6 years. Thirty-four (81%) patients had an infrarenal aortic aneurysm. The average aneurysm diameter was 8.0 + 2.73 cm. The in-hospital survival rate was 95.2% whereas 2 (4.8%) patients had in-hospital mortality. Acute kidney injury (AKI) was the most common complication, seen in 5 (11.9%) patients. Adverse outcomes were seen more in diabetic patients whereas increased incidence of AKI was noted in operations with supra-renal clamping (p<0.05). CONCLUSION: Most patients presented with symptoms and large aneurysm size. Open AAA repair was performed safely with 4.8% in-hospital mortality and acceptable morbidity in the LMIC setting. KEY WORDS: Abdominal aortic aneurysm repair, Low middle-income country.


Asunto(s)
Lesión Renal Aguda , Aneurisma de la Aorta Abdominal , Masculino , Humanos , Persona de Mediana Edad , Anciano , Femenino , Aneurisma de la Aorta Abdominal/cirugía , Mortalidad Hospitalaria , Hospitales Universitarios , Riñón
15.
J Biomol Struct Dyn ; : 1-18, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38197579

RESUMEN

The Dengue virus (DENV) has been increasingly recognized as a prevalent viral pathogen responsible for global transmission of infection. It has been established that DENV's NS5 methyltransferase (MTase) controls viral replication. As a result, NS5 MTase is considered a potentially useful drug target for DENV. In this study, the two phases of virtual screening were conducted using the ML-based QSAR model and molecular docking to identify potential compounds against NS5 of DENV. Four medicinal plants [Aloe vera, Cannabis sativa (Hemp), Ocimum sanctum (Holy Basil; Tulsi), and Zingiber officinale (Ginger)] that showed anti-viral properties were selected for sourcing the phytochemicals and screening them against NS5. Additionally, re-docking at higher exhaustiveness and interaction analysis were performed which resulted in the identification of the top four hits (135398658, 5281675, 119394, and 969516) which showed comparable results with the control Sinefungin (SFG). Post molecular dynamics simulation, 135398658 showed the lowest RMSD (0.4-0.5 nm) and the maximum number of hydrogen bonds (eight hydrogen bonds) after the control while 5281675 and 969516 showed comparable hydrogen bonds to the control. These compounds showed direct interactions with the catalytic site residues GLU111 and ASP131, in addition to this these compounds showed stable complex formation as depicted by principal component analysis and free energy landscape. 135398658 showed lower total binding free energy (ΔGTotal = -36.56 kcal/mol) than the control, while 5281675 had comparable values to the control (ΔGTotal = -34.1 kcal/mol). Overall, the purpose of this study was to identify phytochemicals that inhibit NS5 function, that could be further tested experimentally to treat dengue virus (DENV).Communicated by Ramaswamy H. Sarma.

16.
Environ Sci Pollut Res Int ; 31(2): 3014-3030, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38079035

RESUMEN

In terms of achieving sustainable development goals (SDGs), the developing economies are facing many issues, and one of the key issues is environmental degradation. Being a developing economy, Pakistan is also experiencing thought-provoking impacts of global warming and still far away from the ideal track of sustainable development. For addressing environment-related issue and achieving the targets of SDGs, a policy-level reorientation might be necessary. In this view, this study investigates the impact of economic growth, transport infrastructure, urbanization, financial development, and renewable energy consumption on CO2 emissions by using the data of Pakistan during 1990-2020. For this purpose, we use novel wavelet quantile correlation approach. The empirical results of wavelet quantile correlation approach demonstrate that economic growth, transport infrastructure, urbanization, and financial development are responsible for environmental pollution. Whereas, result also claims that renewable energy consumption is a useful tool for reducing environmental pollution in Pakistan. Moreover, the results of FMOLS approach show that 1% increase in economic growth, transportation infrastructure, urbanization, and financial development increases CO2 emissions by 0.240, 0.010, 0.478, and 0.102%, respectively. However, 1% increase in renewable energy usage reduces CO2 emission by 1.083%. Based on the empirical outcomes, this study proposes comprehensive policy framework for achieving the targets of SDG 7 (clean energy), SDG 8 (economic growth), SDG 11 (sustainable cities and communities), and SDG 13 (climate action).


Asunto(s)
Dióxido de Carbono , Urbanización , Dióxido de Carbono/análisis , Contaminación Ambiental/análisis , Desarrollo Económico , Energía Renovable
17.
Environ Sci Pollut Res Int ; 30(53): 113889-113902, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37858013

RESUMEN

Renewable energy systems are vital for a sustainable future, where solid-state hydrogen storage can play a crucial role. Perovskite hydride materials have attracted the scientific community for hydrogen storage applications. The current work focuses on the theoretical study using density functional theory (DFT) to evaluate the characteristics of MgXH3 (X = Co, Cu, Ni) hydrides. The structural, vibrational, electronic, mechanical, thermodynamic, and hydrogen storage properties of these hydrides were investigated. The equilibrium lattice parameters were calculated using the Birch-Murnaghan equation of state-to-energy volume curves. The elastic constants (Cij) and relevant parameters, such as Born criteria, were calculated to confirm the mechanical stability of the hydrides. The Cauchy pressure (Cp) revealed brittle or ductile behavior. The outcomes of the Pugh ratio, Poisson ratio, and anisotropy were also calculated and discussed. The absence of negative lattice vibrational frequencies in phonon dispersion confirmed the lattice's dynamic stability. The heat capacity curves of thermodynamic properties revealed that hydrides can conduct thermal energy. The metallic character and ample interatomic distances of hydrides were confirmed by the band structure and population analysis, which confirmed that hydrides can conduct electrical energy and adsorb hydrogen. The density of state (DOS) and partial DOS unveiled the role of specific atoms in the DOS of the crystal. The calculated gravimetric hydrogen storage capacity of MgCoH3, MgCuH3, and MgNiH3 hydrides was 3.64, 3.32, and 3.49wt%, respectively. Our results provide a deeper understanding of its potential for hydrogen storage applications through a detailed analysis of MgXH3 (X = Co, Cu, Ni) perovskite hydride material.


Asunto(s)
Compuestos de Calcio , Óxidos , Termodinámica , Hidrógeno
18.
Appl Opt ; 62(19): 5189-5194, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37707222

RESUMEN

Air breakdown is generated by a 1064 nm nanosecond pulsed laser beam, and laser energy deposited in the breakdown (E d), transmitted through the plasma region (E t) and carried away by the shock wave (E s) is estimated for the incident laser energy (E i) range of 60-273 mJ. The E d is approximately 85% of E i at 60 mJ, rapidly increasing to 92% at 102 mJ. The shock wave front velocity and radius are measured as a function of E i and propagation distance. The shock wave velocity nicely follows the v∝E i0.3 trend predicted by the laser-supported detonation wave model. The Sedov-Taylor theory is used to estimate E s, which rapidly increases with E i, but E i to E s conversion linearly decreases from 83% to 48%. At lower values of E i, most of the laser energy is carried away by the shock wave, whereas the laser energy used in plasma heating or released in the form of electromagnetic and thermal radiation becomes important at higher laser energies. This implies that laser energy partitioning is highly dependent on the value of incident laser energy. These findings provide important insights into the fundamental physics of air breakdown and will be useful in a variety of applications such as laser-induced breakdown spectroscopy, laser ignition, and laser propulsion.

19.
J Biomol Struct Dyn ; : 1-21, 2023 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-37707987

RESUMEN

In humans, Epidermal Growth Factor Receptor (EGFR) is linked to small-cell lung cancer, breast cancer, and glioblastoma. Receptor kinase inhibitors against EGFR have become a standard treatment option for non-small cell lung cancer (NSCLC), breast cancer patients, and even for those with EGFR mutations or resistance. About 2734 FDA-approved medication compounds were subjected to virtual screening for EGFR kinase inhibitory activity. The top 30 molecules were chosen based on the binding affinity scores and subjected to extra-precision docking and binding free energy analysis. The ADMET profile of the top three hit molecules was verified to confirm their druggability nature. Top three hits- compound 1047 (ZINC000001550477), 1302 (ZINC00003781952), and 2332 (ZINC000019632618) were identified on account of their MMGBSA binding affinity values. The top three hit compounds were subjected to molecular dynamics (MD) simulation for 100 ns. The dynamic nature of the ligand-protein complex was analyzed which corroborated the results of molecular docking and MMGBSA analysis studies. All the top three hits were further subjected to steered MD studies for testing the strength of these ligand-receptor binding in the presence of an external force. Compound 2332 (ZINC000019632618) was identified as the best hit molecule that can be used as a lead to develop newer derivatives of EGFR kinase inhibitors.Communicated by Ramaswamy H. Sarma.

20.
J Appl Genet ; 64(4): 667-678, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37749479

RESUMEN

Wheat powdery mildew possesses a significant threat to wheat crops not only on a global scale but also in the northern region of Pakistan. Recognizing the need for effective measures, the exploration and utilization of exotic germplasm take on critical importance. To address this, a series of trials were made to investigate the response of 30 European (EU) lines, in addition to the local checks (Siran, Atta-Habib (AH) and Ghanimat-e-IBGE) against wheat powdery mildew at the Himalayan region of Pakistan. The study involved field testing from 2018 to 2022 across multiple locations, resulting in 38 different environments (location × year). In addition to field evaluations, molecular genotyping was also performed. The disease was absent on the tested lines during 2018, 2019, and 2020 whereas it ranged from 0 to 100% at Chitral location during 2021, where 100% was observed only for one EU wheat line "Matrix." The disease prevailed only at Gilgit location (0-60% for EU wheat line "F236") and at Nagar location (0-10% for EU wheat lines Substance and Nelson) during the disease season of 2022. Most of the EU wheat lines showed very low ACI values, due to an overall low disease pressure. Matrix showed the maximum ACI (1.54) followed by Ritter (1.25) and Bli_autrichion (0.87), whereas the minimum (0.1) was for Substance, JB_Asano, and KWS_Loft followed by Canon (0.19), all exhibiting partial resistance. The molecular marker-based screening revealed that Pm38 was the most prevalent and detected in 100% of wheat lines followed by Pm39 (60%) and Pm8 (30%). Six wheat lines (20%) possessed all three Pm genes (Pm8, Pm38, and Pm39) concurrently. The variability observed in this study can be utilized in future breeding efforts aimed at developing resistant wheat varieties.


Asunto(s)
Ascomicetos , Triticum , Triticum/genética , Resistencia a la Enfermedad/genética , Pakistán , Fitomejoramiento , Enfermedades de las Plantas/genética
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