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Nanotechnology has recently appeared as an important study subject in modern material sciences. Greener synthesis of nanoparticles has gained the attention of many scientists because of its integral characteristics such as effectiveness, eco-friendly, and low cost. In the present study by following the green synthesis approach, zinc oxide nanoparticles (ZnO NPs) were formed for the very first time by using Senecio chrysanthemoides leaf extract as a reducing agent. The UV-Vis spectrophotometer was used to study the synthesized ZnO NPs, and the specific peak was found to be at 349 nm. The characteristic Fourier transform infrared (FTIR) peak was found to be at 449 cm-1 which displays the peak of ZnO molecules. The surface morphology of the ZnO NPs was determined via scanning electron microscopy (SEM). The energy-dispersive X-ray spectroscopy (EDX) study showed that the synthesized ZnO NPs are present at the weight percentage of 66.38%. The X-ray diffraction (XRD) spectrum confirmed the hexagonal phase wurtzite structure, with the average particle size of 31 nm, and demonstrated the crystalline structure of ZnO NPs. Additionally, to all these experiments, we compared the anti-inflammatory properties of biogenic ZnO NPs to a standard drug. Biosynthesized ZnO NPs have revealed an effective anti-inflammatory activity at a higher concentration (100 mL-1) and showed 73% inhibition in comparison with diclofenac sodium drug. Zinc oxide was shown to be compatible with diclofenac sodium, according to the results. The ZnO NPs produced using the greener synthesis process have the potential to be used in a broad range of fields and also used as a good anti-inflammatory agent.

A 105-day experimental trial was conducted to assess different levels of dietary Aleo vera extract supplementation on water quality parameters, proximate composition, growth performance and haematological parameters of fry Oreochromis niloticus. Four different percentages of dietary leaf extract powder of Aleo vera (ALE) with a basal feed, designated as, i.e., T0 (Control group; without ALE), T1 (1% ALE), T2 (2% ALE), and T3 (3% ALE). Fish fry was reared in concrete tanks (7.0 m, 1.6 m, 1.0: L, W, H; water volume 11.2 m3/tank), with an average initial weight 4.04 ± 0.03 g/ fry, and each treatment was triplicated. Fry was randomly distributed at a stocking rate of 450 individuals/ tanks. The water quality parameters revealed that temperature, pH, salinity, dissolved oxygen (DO) and nitrates were found in a promising range as given by FAO/WHO limits. However, the record values obtained for Electric Conductivity (EC), Total dissolved solids (TDS), and alkalinities were not found in all tanks' suitable range according to FAO/WHO limits. The results revealed a significant impact of different percentages of dietary ALE supplementation on fry's body composition and haematological parameters. Moreover, the final body weight, final body length, average daily weight gain (g), net weight gain (g) and specific growth rate (%) were significantly higher (p

Development and calibration of distance attenuation curve for local seismic data are requisite for better seismo-tectonic modeling and seismic hazard estimation. Local magnitude scale developed for Northern Punjab (Potwar Plateau and Salt Range) has been tested against different geometrical spreading values. Trade-off or linear inter dependence has been observed between local magnitude scale parameters. To address this issue, either nonparametric approach with proper smoothing factor or parametric approach with single parameter (a) as constant may be used. In this study, we fixed geometrical spreading parameter to eliminate parameters dependency and hence reduction in error was achieved. Geometrical spreading was observed to be distance-dependent factor rather than a constant parameter. A variance reduction of 11%, with zero error in anelsatic attenuation parameter was achieved by fixing geometrical parameter and performing parametric inversion. The new magnitude scale with distance correction factor is given by the expression; $$-{\mathrm{log}}A_o = {\mathrm{log}}(R)+0.0006(R)-1.7419$$ , where R is hypocentral distance, valid for $$R < 130$$ km and depth < 30 km. Lower attenuation (i.e., $$b = 0.0006$$ ) was observed in new magnitude scale as compared to previously developed magnitude scale (i.e., $$b = 0.00115$$ ) for the same area. The pronounced lower attenuation of seismic waves beneath the intraplate region of Northern Punjab is apparently owes to regional tectonics. Northern Punjab is relatively stable part of the Indian shield with Precambrian basement rock overlaid by varying thickness of salt diapirs and thick sedimentary cover.

The alarming energy crises has forced the scientific community to work for sustainable energy modules to meet energy requirements. As for this, ZnO/g-C3N4 nanocomposites with proper heterojunction were fabricated by coupling a proper amount of ZnO with 2D graphitic carbon nitride (g-C3N4) nanosheets and the obtained nanocomposites were applied for photocatalytic hydrogen generation from water under visible light illumination (λ > 420 nm). The morphologies and the hydrogen generation performance of fabricated photocatalysts were characterized in detail. Results showed that the optimized 5ZnO/g-C3N4 nanocomposite produced 70 µmol hydrogen gas in 1 h compare to 8 µmol by pure g-C3N4 under identical illumination conditions in the presence of methanol without the addition of cocatalyst. The much improved photoactivities of the nanocomposites were attributed to the enhanced charge separation through the heterojunction as confirmed from photoluminescence study, capacity of the fabricated samples for •OH radical generation and steady state surface photovoltage spectroscopic (SS-SPS) measurements. We believe that this work would help to fabricate low cost and effective visible light driven photocatalyst for energy production.

Present study was conducted to get information on helminth parasites of zoonotic importance among the black rats of district Swat, Pakistan. Two hundred and sixty nine rats were captured from agricultural ecosystem of the district using live captured traps from 2011 to 2013. Captured rats were anesthetized and surveyed for the presence of ectoparasites, then were carefully dissected for investigation of endoparsites. Helminth parasites of 8 species were identified. Presence of parasite was noticed in 23.7% of sampled rats. The infection rates of sampled rats was given in order of their infectivity as Syphacia obvelata 13(4.83%), Aspiculuris tetraptera 13(4.83%), Heterakis spumosa 12 (4.46%), Hymenolepis spp. 9(3.34%), H.diminuta 8(2.97%), Hymenolepis fusa 4(1.48%), Lutziella microacetabularae 4(1.48%) and Lutziella spp. 1 (0.37%). No significant difference (P

Pakistan and its surroundings are among the most seismically active regions in the world. Occurrence of major earthquakes in Pakistan is a real hazard for life. In this study, an attempt has been made to estimate the seismic hazard in terms of earthquake occurrence conditional probabilities in different zones of Pakistan. We assumed that the temporal data of earthquakes, that occurred in different regions of Pakistan follow a certain probability distribution. In present study, the 10 probability models that include the exponential, gamma, generalized Pareto, inverse Pareto, kappa, log-logistic, lognormal, Pareto, transformed gamma and Weibull are used to analyze the interevent times of the earthquakes with $$M_{w}\ge 5.5$$ in different regions of Pakistan. In current study, Pakistan territory has been divided into five different seismic zones based on their tectonic settings. Parameters of the considered distributions are estimated by using the maximum likelihood method using the reviewed earthquake catalogue compiled by Centre for Earthquake Studies (CES), Pakistan. The best suitable model in each seismic zone is selected through various model selection criteria. The results show that the log-logistic distribution provides the best representation of earthquake temporal data of plate convergence zones; while the gamma distribution best explains the temporal seismicity of other tectonic regimes including the transform plate boundary, fold and thrust belts and stable plains. The most suitable gamma and log-logistic models are used for the earthquake occurrence probabilities in different regions of Pakistan. The highest $$(>96\%)$$ and the least $$(>30\%)$$ earthquake occurrence conditional probabilities are respectively observed for Zones I and V among five seismic zones for different combinations of elapsed time $$(\tau )$$ and time interval $$(\upsilon )$$ . The estimated probability of $$M_{w}\ge 5.5$$ event reaches (60–98)% in next (3–9) years time interval without any elapsed time $$(\tau =0)$$ in Zones II to IV (the time periods corresponding to 3–9 years time interval are 2016–2022, 2020–2026 and 2019–2025 in Zones I, II and III respectively) since the last event occurrence time in each of these seismic zone. The mean values of the interevent time for an earthquake occurrence of $$M_{w}\ge 5.5$$ in Zone-I to Zone-V are respectively calculated as 0.90, 1.78, 4.52, 3.35 and 11.76 years, respectively. The results of the present study indicate that Zone-I has potential capability of producing an earthquake of magnitude 5.5 or higher in next 3 years (2019–2021) time interval since the last event occurrence in May 2018. The earthquake hazard curves associated with earthquake occurrence probabilities are also developed in order to understand the current and future earthquake mechanism in the study region.

Rainbow trout

Good-quality water and food are the basic needs of humans, plants, and animals. Polluted groundwater and soil directly and indirectly affect organisms, which is the main environmental concern. In the current study, standard protocols of atomic absorption spectrometry were adopted for the investigation of selected metals (lead, chromium, and iron) in the collected groundwater and soil samples. The Pearson correlation coefficient (r) applied to groundwater and soil samples shows a positive perfect correlation among water parameters (conductivity and total dissolved solids) in all three sources. In the hand pump samples between water table (WT) and water source depth (WSD), Pearson correlation coefficient (r) value was found (r = 0.87) while between EC and TDS, it was r = 1. Similarly, in the bore hole samples between WT and WSD (r = 0.66), EC and TDS (r = 1), EC and Cr (r = 0.70), and TDS and Cr (r = 0.70), which showed weaker correlation. In the tube well samples, correlation between EC and TDS was high (r = 1). The correlation coefficient (r) values of the soil parameters in the hand pump (soil) samples between Fe and Cr (r = 0.86), in bore hole samples between Fe and Cr (r = 0.77), in tube well samples between Fe and Cr (r = 0.69), while all the other parameter correlations were found lower (r = 0.60). Between electrical conductivity and total dissolved solids, high relation has been observed between them (r = 1). Overall, results showed that in most of the studied samples, contents of the target metals were found above the allowable limit set by the World Health Organization (WHO) and the United States Environmental Protection Agency (USEPA).

The photocatalytic activities of g-C3N4 can be significantly improved by increasing life time of the photogenerated charges. Here, in this work we introduced TiO2 as proper energy platform to accept the photogenerated electrons from g-C3N4 during photocatalysis. The nanophotocatalysts formed from the combination of a suitable amount of TiO2 nanoparticles and g-C3N4 nanosheets showed 8.75 and 4.22% enhancement in photocatalytic activities for CO2 reduction and 2-chlorophenol (2-CP) degradation under visible light illumination as compared to bare g-C3N4. Based on the surface photovoltage spectra, photoluminescence spectra and examination of formed hydroxyl radicals, it was confirmed that these enhanced photoactivities were attributed to the much-improved charge separation via the electron transfer from g-C3N4 to TiO2. From trapping experiments, it was found that hydroxyl radicals were the major species involved in the photocatalytic degradation of 2-CP. This study is helpful to synthesize efficient photocatalysts to cope with energy and environmental issues. Keywords: Nanophotocatalyst, Charge separation, CO2 reduction, Pollutant degradation

The probabilistic models achieved considerable attention in the field of seismology due to their dynamic properties. In this study, an attempt has been made to quantify the uncertainty observed in the earthquake data of the Hindu Kush region by using probabilistic models. The conditional probabilities of major earthquake (Mw ≥ 5.5) occurrence in the Hindu Kush region are estimated by using the Weibull, lognormal, gamma, and log-logistic probability distributions. The maximum likelihood estimation method has been used to estimate the model parameters. Results based on the three model selection criteria suggest that the Weibull and log-logistic distributions provide the most appropriate fit, while the lognormal and gamma distributions appeared as the second and third appropriate fitted distributions to the elapsed time data of the Hindu Kush region. Using the most appropriate fitted Weibull and log-logistic distributions, it has been observed that the estimated earthquake occurrence probability of magnitude 5.5 or greater in the Hindu Kush region reaches 0.94–0.99 within next 3 to 6 (2021–2024) years since the last event occurred in 2018 in the study region. The conditional probability values are continuously increasing with increasing time interval and it approximately reaches to one in next 6 to 12 (2024–2030) years without any elapsed time, i.e., (T = 0) years. The estimated earthquake conditional probability curves for different elapsed time and time interval values are also presented to understand the earthquake genesis in the study region. The earthquake mean recurrence interval is 0.68, 0.81, 0.68, and 1.11 years by using the Weibull, lognormal, gamma, and log-logistic models respectively. According to the obtained results, the earthquake of magnitude Mw ≥ 5.5 occurrence probability in the study region is significantly high. The obtained results provide important information’s regarding the underlying physical mechanism of earthquake generation process in the Hindu Kush region.

The applications of nanotechnology in different fields of medical science have revolutionized the healthcare sector for the diagnosis and treatment of several lethal diseases including cancer. Magnetic nanoparticles (MNPs) are one of the most used nanomaterials in disease diagnosis, targeted drug delivery, and biomedical imaging, such as magnetic resonance imaging (MRI). The unparalleled magnetic properties of the MNPs assigned certain characteristic features such as they can be used at the cellular and molecular level in a biological system and are also suitable materials to be used in drug delivery and MRI. The MNPs are in the front line, providing an attractive platform as alternative agents, as carriers in drug delivery and MRI. To better address the specific biomedical needs, MNPs with higher magnetic moments, specific size and surfaces, with enhanced functionalities, have great applications in the detection, diagnosis, targeted drug delivery, and treatment of different diseases such as cardiovascular disease, different types of malignant tumors, and neurological ailments. To date, various types of MNPs have been designed and synthesized according to their applications in detection of diseases, targeted drug delivery to various disease sites and different body parts, monitoring drug delivery, and also disease treatment. This chapter will provide an insight view of the design, synthesis, and applications of MNPs in disease diagnosis, targeted drug delivery, and MRI.

Selenium (Se) is a dietary essential trace element with important biological roles. It is a nutrient related to the complex metabolic and enzymatic functions. Organoselenium compounds have been reported to have anti-ulcer activity and used as drug for the treatment of gastrointestinal disorders. The antiulcer activity of binapthyl diselenide (NapSe)2 was investigated in ethanol-induced gastric lesions in rats. A number of markers of oxidative stress were examined in rats stomach including thiobarbituric acid reactive species (TBARS), catalase (CAT), superoxide dismutase (SOD), non-protein thiol groups (NPSH) and ascorbic acid. (NapSe)2 was found to be significantly restoring the deficits in the antioxidant defense mechanisms (CAT, SOD, NPSH and ascorbic acid), and suppressed lipid peroxidation in rat stomach resulting from EtOH administration. It is experimentally concluded that ethanol exposure causes alterations in the antioxidant defense system and induces oxidative stress in rat stomach. These studies establish a promising foundation for investigating and understanding the beneficial effects of organoselenium compounds on human health. Moreover, (NaPSe)2 deserves further investigation as a therapeutic and preventive agent against gastric ulcer in humans.

Identification of metal cluster catalysis is a topic that is being investigated since a long time. Here, we report a Pd3 metal cluster catalytic reaction investigated by means of operando studies. We discovered that atomically defined tri-nuclear palladium (Pd3) is a surprisingly active catalyst for the cycloisomerization of 2-phenylethynylaniline. Operando 1H NMR spectroscopy and X-ray extended absorption fine structure (EXAFS) measurements have indicated that the structural integrity of such a catalyst remains intact throughout the reaction, which has also been confirmed by an ex situ X-ray photoelectron spectroscopy (XPS) study and catalyst recycling experiments. Kinetic data derived from operando IR spectroscopy measurements have shown that Pd3 is the active catalytic species. Density functional theory calculations have revealed a reaction pathway consistent with the kinetic data, further supported by NMR titration and X-ray crystal structure studies. Overall, the present study presents a clear example of metal cluster catalysis.

The introduction of a 4-mercaptan substituent was recently reported to be effective to improve the reactivity of C-terminal prolyl thioesters in native chemical ligation (NCL). To elucidate the origin of the high reactivity of 4-mercaptoprolyl thioesters, a theoretical study was performed on the transthioesterification of NCL herein with the aid of density functional theory (DFT) methods. The calculation results support a transthioesterification mechanism involving two stages. The first stage is the intramolecular transthioesterification of 4-mercaptoprolyl thioesters to form a bicyclic thiolactone intermediate and the second stage is the intermolecular transthioesterification of the thiolactone intermediate with N-terminal cysteine. The two stages proceed both via nucleophilic attack of the thiolate and proton-donor-assisted thiolate release. The thiolate release in the first stage is the rate-determining step of the whole transthioesterification of 4-mercaptoprolyl thioesters. Based on the mechanistic details, further analysis was conducted to gain a deeper insight with natural bond orbital (NBO) analysis, non-covalent interaction plots (NCIplots), distortion analysis, etc. The n → π* interaction between the N-carbonyl oxygen and thioester carbonyl was found to be detrimental to the first stage while a previously unnoticed n → π* interaction between the amide nitrogen and the thiolactone carbonyl slightly benefits the second stage. The entropy effect was the main driving force for the first stage because this stage is an intramolecular one-to-two process overall. On the other hand, the release of the ring stain precluded in the bicyclic thiolactone intermediate is mainly responsible for the high reactivity of the thiolactone in the second stage compared with other prolyl thioesters. Meanwhile, the intramolecular hydrogen bond between the thiolactone carbonyl oxygen and the protonated amine of N-terminal cysteine also contributes to the transthioesterification.

In the molecule of the title compound, C14H18N2O2S2, the 1,3,5-thiadiazinane-2-thione ring adopts an envelope conformation with one of the N atoms at the flap position. The plane throught the five co-planar atoms of the heterocycle is oriented at a dihedral angle of 80.59 (8)° with respect to the aromatic ring. In the crystal structure, weak intermolecular O—H...S interactions link the molecules into chains along the b axis.

In the title compound, C(14)H(20)N(2)S(2), the 1,3,5-thia-diazinane-2-thione ring adopts an envelope conformation. The S=C bond length is 1.6776 (15) Å, whereas the S-C bond lengths are 1.7470 (15) and 1.8479 (17) Å. The intramolecular C-H⋯S hydrogen bond between the thione and the benzyl units along with the C-H⋯π interaction between the butyl group and the centroid of the benzene ring may be effective in stabilizing the molecule.