Assessment of the potential impacts of climate change on the hydrology at catchment scale: modelling approach including prediction of future drought events using drought indices

Abstract: In this study, the Distributed Catchment-Scale Model, DiCaSM, was used to study the impact of climate change on the hydrology of the Eden catchment, north east of Scotland. As a first step, the model was successfully calibrated and validated for a 42 years period. The DiCaSM model was then used to study the impact of climate change on the water availability. Data from the UKCP09 Climate change scenarios for the 2010–2039, 2040–2069 and 2070–2099 periods, considering three gas emission scenarios (low, medium and high), were applied. The results indicated that the greatest decrease in streamflow and groundwater recharge was projected to happen under the high emission scenarios towards the end of the century, i.e. between 2070 and 2099. This would mainly be due to the summers becoming drier. Meanwhile, the projected increase in winter precipitation did not contribute much towards groundwater recharge due the projected increases in evapotranspiration and soil moisture deficit. The following drought indices were calculated and were found to be effective in predicting different types of droughts: the Standardized Precipitation Index, SPI, and the Standardized Precipitation Evaporation Index, SPEI, the Reconnaissance Drought Index, RDI, the modified adjusted RDI, the Soil Moisture Deficit, SMD and the Wetness Index, WI. The findings of the study have broader implications in water resources management considering the future changes in climate

Drop size in a liquid pulsed sieve-plate extraction column

Peer reviewedPublisher PD

Solubility enhancement of poorly water soluble drugs using liposome technology

The aim of this work is to investigate the various parameters that could control the encapsulation of lipophilic drugs and investigate the influence of the physical properties of poorly water-soluble drugs on bilayer loading. Initial work investigated on the solubilisation of ibuprofen, a model insoluble drug. Drug loading was assessed using HPLC and UV spectrophotometric analysis. Preliminary studies focused on the influence of bilayer composition on drug loading to obtain an optimum cholesterol concentration. This was followed up by studies investigating the effect of longer alkyl chain lipids, unsaturated alkyl chain lipids and charged lipids. The studies also focused on the effects of pH of the hydration medium and addition of the single chain surfactant a-tocopherol. The work was followed up by investigation of a range of insoluble drugs including flurbiprofen, indomethacin, sulindac, mefenamic acid, lignocaine and progesterone to investigate the influence of drugs properties and functional group on liposomal loading. The results show that no defined trend could be obtained linking the drug loading to the different drug properties including molecular weight, log P and other drug specific characteristics. However, the presence of the oppositely charged lipids improved the encapsulation of all the drugs investigated with a similar effect obtained with the substitution of the longer chain lipids. The addition of the single chain surfactant a-tocopherol resulted in enhancement of drug loading and possibly is governed by the log P of the drug candidate. Environmental scanning-electron microscopy (ESEM) was used to dynamically follow the changes in liposome morphology in real time during dehydration thereby providing a alternative assay of liposome formulation and stability. The ESEM analysis clearly demonstrated ibuprofen incorporation enhanced the stability of PC:Chol liposomes

Functionalised particles using dry powder coating in pharmaceutical drug delivery:promises and challenges

Introduction: Production of functionalised particles using dry powder coating is a one-step, environmentally friendly process that paves the way for the development of particles with targeted properties and diverse functionalities. Areas covered: Applying the first principles in physical science for powders, fine guest particles can be homogeneously dispersed over the surface of larger host particles to develop functionalised particles. Multiple functionalities can be modified including: flowability, dispersibility, fluidisation, homogeneity, content uniformity and dissolution profile. The current publication seeks to understand the fundamental underpinning principles and science governing dry coating process, evaluate key technologies developed to produce functionalised particles along with outlining their advantages, limitations and applications and discusses in detail the resultant functionalities and their applications. Expert opinion: Dry particle coating is a promising solvent-free manufacturing technology to produce particles with targeted functionalities. Progress within this area requires the development of continuous processing devices that can overcome challenges encountered with current technologies such as heat generation and particle attrition. Growth within this field requires extensive research to further understand the impact of process design and material properties on resultant functionalities

Characterisation and surface-profiling techniques for composite particles produced by dry powder coating in pharmaceutical drug delivery

The production of composite particles using dry powder coating is a one-step, environmentally friendly, process for the fabrication of particles with targeted properties and favourable functionalities. Diverse functionalities, such flowability enhancement, content uniformity, and dissolution, can be developed from dry particle coating. In this review, we discuss the particle functionalities that can be tailored and the selection of characterisation techniques relevant to understanding their molecular basis. We address key features in the powder blend sampling process and explore the relevant characterisation techniques, focussing on the functionality delivered by dry coating and on surface profiling that explores the dynamics and surface characteristics of the composite blends. Dry particle coating is a solvent- and heat-free process that can be used to develop functionalised particles. However, assessment of the resultant functionality requires careful selection of sensitive analytical techniques that can distinguish particle surface changes within nano and/or micrometre ranges

Mass transfer efficiency of a tall and low plate free area liquid pulsed sieve-plate extraction column

Acknowledgements The authors would like to acknowledge Chakwal group of industries for funding the project. Ms. Madiha, Ms. Zona, Mr. Sohaib, Mr. Abdullah, Mr. Mudassar, and Mr. Salahuddin also deserve our acknowledgements for their assistance in different ways.Peer reviewedPublisher PD

Genetic study of phenylthiocarbamide (PTC) taste perception among six human populations of Jammu and Kashmir (India)

Background: The ability to taste phenylthiocarbamide (PTC), a bitter chemical has long been known to be a bimodal autosomal trait inherited in a simple Mendelian recessive pattern which is being widely used for both genetic and anthropological studies. The frequency of taster and non-taster allele is found to vary in different populations. The present paper deals with the distribution of PTC tasting ability as a marker to study the genetic structure among Muslim populations of Jammu; as no detailed information is available.Aim: To investigate the prevalence and gene frequencies of PTC taste sensitivity among male and females.Subjects and methods: We have undertaken a survey of gene frequencies of PTC taste ability for six different endogamous groups including tribal population. PTC serial dilution method was used to assess the PTC taster and non-taster phenotypes. Hardy–Weinberg method was used to determine allele frequencies.Results: Gujjar and Bakarwal population showed highest PTC threshold while Syed had the least. The phenotypic frequency for PTC taste ability varies within six populations; Syed were observed with highest taster frequency while Gujjar and Bakarwal had lowest taster frequency. The taster frequency of six different populations showed that the percentage of taster frequency was more frequent than that of the non-tasters. Also, females (x2= 4.563, df =5, p= 0.471) had more PTC tasters than males (x2= 5.254, df =5, p= 0.385), being statistically significant. The allelic frequencies in Gujjar and Bakarwal for non-taster (t) males and females were 55.86 and 54.55, respectively. In Syed population, t-allele frequencies for males and females were 45.75 and 37.79, respectively, while the other four populations showed intermediate t-allele frequencies. The heterozygosity showed little variation among all of the six populations.Keywords: Phenylthiocarbamide (PTC); PTC threshold; Gene frequency; Genotype frequency; Heterozygosity; Human populatio

Prevalence and gene frequencies of A1A2BO and Rh(D) blood group alleles among some Muslim populations of North India

Background: Research on ABO group system has been of immense interest, due to its medical importance in different diseases. Till date only a few studies have been done on the prevalence and gene frequencies of A1A2BO and Rh(D) blood groups among the Muslim populations ofUttar Pradesh, North India. The data generated in the present work may be useful for health planners while making efforts to face the future health challenges in the region.Aim: This study was conducted to determine the prevalence and gene frequencies of A1A2BO and Rh(D) blood groups among six Muslim populations of Aligarh district, Uttar Pradesh, North India.Subjects and methods: Blood samples from a total of 724 healthy, unrelated individuals were drawn at random from the six different endogamous groups of Muslim populations of Uttar Pradesh, North India. A1A2BO and Rh blood grouping were carried out by standard slide agglutination method and allele frequencies were determined.Results: In total 724 samples analyzed, the most frequent blood group was found to be group O 29.97% (n= 217), followed by A1 26.52% (n=192), B 20.03% (n= 145), A1B 19.34% (n= 140), A2 2.90% (n= 21) and A2B 1.24% (n= 9). The overall phenotypic frequencies of A1A2BO blood groups were O >A1>B> A1B>A2>A2B. The calculated allelic frequencies were 0.5619, 0.2214, 0.1973 and 0.0259 for group Io, Ib, Ia1 and Ia2, respectively. The Chi-square differences for A1A2BO blood groups among different Muslim populations were found to be significant (v2 =41.22, df= 25, p <0.02). Out of total 724 samples, 613 (84.67%) samples were Rh+ve and 111 (15.33%) were Rhve

Multimodal role of amino acids in microbial control and drug development

Amino acids are ubiquitous vital biomolecules found in all kinds of living organisms including those in the microbial world. They are utilised as nutrients and control many biological functions in microorganisms such as cell division, cell wall formation, cell growth and metabolism, intermicrobial communication (quorum sensing), and microbial‐host interactions. Amino acids in the form of enzymes also play a key role in enabling microbes to resist antimicrobial drugs. Antimicrobial resistance (AMR) and microbial biofilms are posing a great threat to the world’s human and animal population and are of prime concern to scientists and medical professionals. Although amino acids play an important role in the development of microbial resistance, they also offer a solution to the very same problem i.e., amino acids have been used to develop antimicrobial peptides as they are highly effective and less prone to microbial resistance. Other important applications of amino acids include their role as anti‐biofilm agents, drug excipients, drug solubility enhancers, and drug adjuvants. This review aims to explore the emerging paradigm of amino acids as potential therapeutic moieties

Biochar from microwave pyrolysis of selected feedstocks

This is a brief summary of work carried out by a team of researchers to produce biochar using microwave pyrolysis system developed at Bioenergy, Bioproducts Research Lab (BBRL), at UNB. Various feedstocks such as corn stalk, spruce, maple, switchgrass, and wood pellets were used to produce biochar. A batch type microwave reactor with a frequency of 2.45 GHz and a power generator of 3 kW was used in the pyrolysis experiments. The amount of biochar obtained depends on the microwave pyrolysis conditions and type of feedstock. For corn stalk briquettes, the yield of biochar ranged from 30.9 to 41.1 wt%. The average biochar yield for spruce, maple, and switchgrass was found to be 22.2 wt%, 22.0 wt%, and 24.4 wt% respectively. Please click on the file below for full content of the abstract