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Rapid technological advancement in solar applications requires accurately determined daily global solar radiation (DGSR). The independent models to predict DGSR are super cited as they do not require any other climatological or geographical parameter. In this study, nine day-of-the-year based (DYB) independent models are developed to estimate daily global solar radiation in Pakistan. The meteorological data from the year 2000–2017 is used while covering thirty locations from five climatic zones of Pakistan. The models’ performance is statistically assessed in terms of normalized mean bias error (nMBE) and normalized root mean square error (nRMSE). The results indicate that the two Gaussian function model estimates DGSR with a satisfactory performance at most stations in different climatic zones. On average, the correlation coefficient and index of agreement between day-of-the-year and DGSR are 0.934 and 0.956, respectively. The two Gaussian function model is then further compared with four existing best claimed models found in literature. Results show that the nMBE and nRMSE ranges from 0.87 to 3.00 and 0.95 to 3.21, respectively. Thus, it shows that the existing models overestimate the DGSR and are not applicable for long-term planning. In comparison, for the present study, nMBE and nRMSE take values between −0.05 to 0.17 and 0.09 to 0.24, respectively. Furthermore, Global Performance Indicator (GPI) is used to rank the models based upon their prediction performance which ranges between −3.5626 and 4.1998. The study revealed that DYB models are best suited for hot climatic regions of Pakistan as compared to cold climatic zones. Also, the locations within the China Pakistan Economic Corridor (CPEC) highway network have maximum accuracy. This study can help energy system designers to predict DGSR values at any location in Pakistan. [ABSTRACT FROM AUTHOR]

In the present study, stabilizer caged fluorescent rhodamine B mesoporous silica particles with special shapes were prepared. The prepared particles have a pore volume of 1.92 cm3/g and a pore diameter of 12 nm. The abundant hydroxyl functional groups of mesoporous silica are responsible for the superior loading capacity of target molecular specie. The appearance of bands due to –COOH, –CH3, –CH2, –NH etc. indicated that the fluorescent rhodamine B could be encaged with the stabilizer inside the mesoporous channels. The performance of mesostructured origami silica matrix was evaluated by in vitro release experiments. From the in vitro release results, this material is suggested to have appropriate features for almost no release at pH = 1.2 and very slow release at neutral pH value. The same material could be best employed at pH 4.5 and at high pH values. It is concluded that mesostructured origami silica matrix is a smart nano-platform and can be utilized for high retention of cargo molecules. [ABSTRACT FROM AUTHOR]

The over expression of melanogenic enzymes like tyrosinase caused many hyperpigmentaion disorders. The present work describes the synthesis of hydroxy substituted 2-[(4-acetylphenyl)amino]-2-oxoethyl derivatives 3a–e and 5a–e as antimelanogenic agents. The tyrosinase inhibitory activity of synthesized derivatives 3a–e and 5a–e was determined and it was found that derivative 5c possesses excellent activity with IC50 = 0.0089 µM compared to standard kojic acid (IC50 = 16.69 µM). The presence of hydroxyl groups at the ortho and the para position of cinnamic acid phenyl ring in compound 5c plays a vital role in tyrosinase inhibitory activity. The compound 5d also exhibited good activity (IC50 = 8.26 µM) compared to standard kojic acid. The enzyme inhibitory kinetics results showed that compound 5c is a competitive inhibitor while 5d is a mixed-type inhibitor. The mode of binding for compounds 5c and 5d with tyrosinase enzyme was also assessed and it was found that both derivatives irreversibly bind with target enzyme. The molecular docking and molecular dynamic simulation studies were also performed to find the position of attachment of synthesized compounds at tyrosinase enzyme (PDB ID 2Y9X). The results showed that all of the synthesized compounds bind well with the active binding sites and most potent derivative 5c formed stable complex with target protein. The cytotoxicity results showed that compound 5c is safe at a dose of 12 µg/mL against murine melanoma (B16F10) cells. The same dose of 5c was selected to determine antimelanogenic activity; the results showed that it produced antimelenogenic effects in murine melanoma (B16F10) cells. Based on our investigations, it was proposed that compound 5c may serve as a lead structure to design more potent antimelanogenic agents. [ABSTRACT FROM AUTHOR]

The present study was conducted to evaluate the effects of storage time and temperature on physicochemical and sensory properties and to measure the spoilage of pasteurized fluid milk stored at different temperatures via nanoparticles on pasteurized fluid milk. The mean values for pH of milk samples decreased (from 6.81 to 6, 5.46, and 4.37), acidity increased (10%, 21%, and 35%), fat contents decreased (13%, 24%, and 32%), protein contents decreased (7%, 18%, and 24%), lactose contents decreased (5%, 7%, and 12%), and total free fatty acids increased (14%, 19%, and 27%) respectively at 4°C, 7°C, and 10°C. Similarly, the score of sensory parameters like aroma, taste, and overall acceptability decreased 16%, 23%, and 45%; 31%, 43%, and 52%; and 33%, 42%, and 53% respectively in linear pattern along with increasing the time and temperature. The L* values were non-significantly changed or decreased with mean values of 64.82 ± 0.08 to 64.13 ± 0.07 at 4°C and significantly with 64.81 ± 0.03 to 63.87 ± 0.07 and 64.77 ± 0.02 to 61.43 ± 0.05 at 7°C and 10°C respectively at 0–19th day of milk storage. During storage, the pasteurized milk stored at all temperatures 4°C, 7°C, and 10°C showed that a* value non-significantly decreased from 48.69 ± 0.18 to 48.63 ± 0.18, 48.74 ± 0.14 to 48.57 ± 0.11, and 48.68 ± 0.18 to 47.97 ± 0.07 respectively. Values of b* decreased non-significantly at 4°C and 7°C with the values of −17.56 ± 0.23 to −18.58 and −17.54 ± 0.25 to −19.85 ± 0.85 but significantly decreased at 10°C from −17.56 ± 0.23 to −43.22 ± 0.11. The results suggested that pasteurized milk can be kept for 17–19 days at 4°C but this shelf life drastically reduced at 7°C and 10°C. Color of nanoparticles was significantly changed from pink to dark blue from 14th day of storage onwards to the end at 10°C. Conclusively, nanoparticles can be used for the rapid and at the post-spoilage measurement of pasteurized milk. [ABSTRACT FROM AUTHOR]

The proper designing and monitoring of solar application require accurate estimation of solar diffuse radiations. In this study, new empirical models are developed from for four selected cities: Karachi, Multan, Quetta, and Peshawar, representing four provinces of Pakistan with the help of recently measured data under Energy Sector Management Assistance Program (ESMAP) of World Bank. Sky-clearness index is selected as an input parameter because of close correlation with the diffuse fraction. Models are developed from six different groups available in the literature for daily radiations. Nine statistical indicators are analyzed to select the best-suited model. Results show that the best-suited model for Karachi, Multan, Quetta, and Peshawar is cubic, exponential, cubic, and quadratic, respectively. In general, polynomial models show better estimate, whereas logarithmic models show the worst results for every case. This study would be helpful for proper design, evaluation, and parametric studies of solar applications throughout the country as well as useful for locations with similar climatic conditions. [ABSTRACT FROM AUTHOR]

The anti-inflammatory potential of extracts of all parts of Caesalpinia pulcherrima and fractions of fresh pods were explored. Each part of C. pulcherrima was extracted with methanol, acetone, and water. Fresh pods were further processed for fractionation. Methanol extract of pods (CP-Pods-M, 292 g) was subjected to solvent-solvent separation, which gave hexane (PE), ethyl acetate (EA), butanol (BUT), and aqueous (AQ) phases separately. EA phase (EA INSOLUBLE) was washed with water (EA AQ WASH) and dried with anhydrous Na2SO4 then treated with charcoal. It was further filtered and termed as EA 1 + 2 and EA 1. Hexane (P.E) phase was evaporated to give fraction PE 1 + 2. Aqueous phase provided aqueous fractions (AF) and the residue left after freeze-drying was termed as aqueous deposit (AD). The effect of all extracts of the plant and fractions of fresh pods were studied for oxidative burst activity of whole blood phagocytes, neutrophils, and murine macrophages J 774.2 by using chemiluminescence technique. Antioxidant potential was also evaluated by DPPH radical scavenging assays. Inhibition on reactive oxygen species (ROS) production of whole blood phagocytes was observed with IC50 values ranging between 1.6 ± 0.78-8.0 ± 0.8 µg mL−1, which was lower than the standard ibuprofen as assessed by methanolic extracts of fresh fruit and flower, acetone and aqueous extracts of dry fruits and their coat, aqueous and acetone extracts of fresh fruit and their coat. The fractions EA INSOLUBLE, EA AQ WASH, EA 1 + 2, PE 1 + 2, AF, AD, and EA 1 exhibited inhibition on ROS by whole blood cells, IC50 values ranges (1.62-9.18 µg mL−1). Extracts of the plant and fractions from fresh pods also inhibited intracellular and extracellular ROS production in the isolated human neutrophils and murine macrophage cells J774.2. [ABSTRACT FROM AUTHOR]

Objectives: One of the most common non-motor symptoms in Parkinson's disease (PD) is nocturia. This paper seeks to address the prevalence of nocturia in PD and correlate it to various factors such as gender, Hoehn and Yahr (H&Y) stage, age, and ethnicities. Methods: In particular, 332 PD patients were seen in a community movement disorders clinic and their charts were analyzed from 2005 to 2010. Within this population, more than one-third (34.9%) patients were diagnosed with nocturia. Results: Age, gender, and PD stage were significant predictors of nocturia in PD. With every one-year increase in age, the odds of developing nocturia in PD increases by 3.1% while an increase in H&Y stage increases the odds of nocturia in PD by 1.645 times. Also, males had greater odds of experiencing nocturia in PD. Ethnicities alone were of no significant importance. However, after performing interaction analyses, Asian and Indian males, especially, were at significantly greater risk than other ethnicities. Discussion: Future research is indeed required to understand why certain ethnicities are especially at risk. Clinicians must also be aware of the epidemiology of nocturia in PD to prevent and treat this debilitating symptom. [ABSTRACT FROM AUTHOR]