Enzymatic Synthesis of Palm Based Amino Acid Esters

Acyllysines were successfully prepared from reactions of free fatty acids (FFAs) (palmitic acid, PA; oleic acid, OA), triglycerides (TGs) (tripalmitin, TP ; triolein, TO) and palm oil fractions (palm olein, PO; palm kernel olein, PK O) with the unprotected amino acid, L-lysine, using enzymes as biocatalyst in an organic solvent system. Such a selective enzymatic route obviates the fastidious regime of substrate activation/protection required in chemical synthesis. Preliminary detection and identification of reaction products were facilitated by thin layer chromatography (TLC) while subsequent quantitative studies on main and interactive effects of parameters governing the reactions were conducted with TLC-photodensitometry. Enzyme screening revealed Lipozyme IM to be the most efficient biocatalyst for the reactions. By varying one-parameter-at-a-time, 70°C was shown to be the optimal temperature, hexane, the most suitable solvent, and, 5:1 (PA:L-lysine), 3:1 (OA:L-lysine), 1:1 (TP:L-lysine), 1:3 (TO:L-lysine), 1:1 (pO:L-lysine) and 1:I(PKO:L-lysine) the respective optimal substrate molar ratios. To reach equilibrium, reactions of FF As and TGs with L-lysine required 4 days while those of the more complex PO and PKO required 6 days. Higher biocatalyst amounts improved all reactions (except that of TP with L-lysine), as did higher amounts of molecular sieves added to reactions ofOA and TO with L-lysine

The relationship between perceived parenting styles and stress levels among Malaysian secondary school students

This research aimed to investigate the relationship between parenting styles and stress level among Malaysian adolescents. A final sample of 140 participants with equal number of males and females, with ages ranging from 13 to 16 years old were recruited. Data collection was conducted in two public secondary schools in Pahang. This survey included three instruments: Parental Authority Questionnaire (PAQ), Adolescent Stress Questionnaire (ASQ) and demographic questionnaire. The results showed mothers prefer authoritative parenting compared to fathers and that parenting styles are not related to adolescents? stress level. There was also no gender difference in adolescents? stress level in home-life, peer pressure and school performance. Recommendations for future studies and implications of study are discussed

Effects of family functioning and family hardiness on self-efficacy among college students

Family functioning has been related to numerous developmental problems. Although there are other factors affecting a student?s self-efficacy, this research focused on the effects of family functioning and family hardiness. The implications that family functioning plays a great role in shaping one?s self belief systems will help to emphasize the need to resolve a growing cycle of social issues. The objectives of this study is to find out whether family functioning and family hardiness will have an influence on students? self-efficacy and also to determine the level of difference in self-efficacy of male and female students. Participants involved in this study were made up of a random sample of 120 students from a few colleges in the state of Selangor. Results obtained from this research study showed that there is a correlation amongst all three variables used, namely, family functioning, family hardiness and self-efficacy are interrelated. In addition, the results also showed that more males than females have been categorized in the category of clinical group for family functioning and selfefficacy

Estimation of subsurface porosities and thermal conductivities of polygonal tundra by coupled inversion of electrical resistivity, temperature, and moisture content data

Studies indicate greenhouse gas emissions following permafrost thaw will amplify current rates of atmospheric warming, a process referred to as the permafrost carbon feedback. However, large uncertainties exist regarding the timing and magnitude of the permafrost carbon feedback, in part due to uncertainties associated with subsurface permafrost parameterization and structure. Development of robust parameter estimation methods for permafrost-rich soils is becoming urgent under accelerated warming of the Arctic. Improved parameterization of the subsurface properties in land system models would lead to improved predictions and a reduction of modeling uncertainty. In this work we set the groundwork for future parameter estimation (PE) studies by developing and evaluating a joint PE algorithm that estimates soil porosities and thermal conductivities from time series of soil temperature and moisture measurements and discrete in-time electrical resistivity measurements. The algorithm utilizes the Model-Independent Parameter Estimation and Uncertainty Analysis toolbox and coupled hydrological-thermal-geophysical modeling. We test the PE algorithm against synthetic data, providing a proof of concept for the approach. We use specified subsurface porosities and thermal conductivities and coupled models to set up a synthetic state, perturb the parameters, and then verify that our PE method is able to recover the parameters and synthetic state. To evaluate the accuracy and robustness of the approach we perform multiple tests for a perturbed set of initial starting parameter combinations. In addition, we varied types and quantities of data to better understand the optimal dataset needed to improve the PE method. The results of the PE tests suggest that using multiple types of data improve the overall robustness of the method. Our numerical experiments indicate that special care needs to be taken during the field experiment setup so that (1) the vertical distance between adjacent measurement sensors allows the signal variability in space to be resolved and (2) the longer time interval between resistivity snapshots allows signal variability in time to be resolved

Secondary metabolites from two garcinia species and their biological activities.

Detail chemical studies on Garcinia maingayi have yielded one xanthone, 1,3,7-trihydroxy-2-(3-methylbut-2-enyl)xanthone, one benzophenone, isoxanthochymol, one benzoic acid derivative 3,4-dihydroxy-methylbenzoate and two triterpenoids, stigmasterol and sitosterol. Meanwhile, investigations on Garcinia parvifolia have afforded one triterpenoid, α-amyrin and two xanthones, cowanin and rubraxanthone. Their structures were derived based on spectroscopic evidence, mainly 1D and 2D NMR spectroscopy. Acetylation reaction was carried out on rubraxanthone to yield triacetate rubraxanthone. It was found that the pure rubraxanthone was strongly active against the larvae of Aedes aegypti with LC50 value of 15.49 μg/mL and HL-60 cell line with an IC50 value of 7.5 μg/mL

Skyrmion fluctuations at a first-order phase transition boundary

Magnetic skyrmions are topologically protected spin textures with promising prospects for applications in data storage. They can form a lattice state due to competing magnetic interactions and are commonly found in a small region of the temperature - magnetic field phase diagram. Recent work has demonstrated that these magnetic quasi-particles fluctuate at the μeV energy scale. Here, we use a coherent x-ray correlation method at an x-ray free-electron laser to investigate these fluctuations in a magnetic phase coexistence region near a first-order transition boundary where fluctuations are not expected to play a major role. Surprisingly, we find that the relaxation of the intermediate scattering function at this transition differs significantly compared to that deep in the skyrmion lattice phase. The observation of a compressed exponential behavior suggests solid-like dynamics, often associated with jamming. We assign this behavior to disorder and the phase coexistence observed in a narrow field-window near the transition, which can cause fluctuations that lead to glassy behavior

International Veterinary Epilepsy Task Force Consensus Proposal: Diagnostic approach to epilepsy in dogs

This article outlines the consensus proposal on diagnosis of epilepsy in dogs by the International Veterinary Epilepsy Task Force. The aim of this consensus proposal is to improve consistency in the diagnosis of epilepsy in the clinical and research settings. The diagnostic approach to the patient presenting with a history of suspected epileptic seizures incorporates two fundamental steps: to establish if the events the animal is demonstrating truly represent epileptic seizures and if so, to identify their underlying cause. Differentiation of epileptic seizures from other non-epileptic episodic paroxysmal events can be challenging. Criteria that can be used to make this differentiation are presented in detail and discussed. Criteria for the diagnosis of idiopathic epilepsy (IE) are described in a three-tier system. Tier I confidence level for the diagnosis of IE is based on a history of two or more unprovoked epileptic seizures occurring at least 24 h apart, age at epileptic seizure onset of between six months and six years, unremarkable inter-ictal physical and neurological examination, and no significant abnormalities on minimum data base blood tests and urinalysis. Tier II confidence level for the diagnosis of IE is based on the factors listed in tier I and unremarkable fasting and post-prandial bile acids, magnetic resonance imaging (MRI) of the brain (based on an epilepsy-specific brain MRI protocol) and cerebrospinal fluid (CSF) analysis. Tier III confidence level for the diagnosis of IE is based on the factors listed in tier I and II and identification of electroencephalographic abnormalities characteristic for seizure disorders. The authors recommend performing MRI of the brain and routine CSF analysis, after exclusion of reactive seizures, in dogs with age at epileptic seizure onset 6 years, inter-ictal neurological abnormalities consistent with intracranial neurolocalisation, status epilepticus or cluster seizure at epileptic seizure onset, or a previous presumptive diagnosis of IE and drug-resistance with a single antiepileptic drug titrated to the highest tolerable dose

Unravelling the pathogenesis of type 2 diabetes

PhD ThesisType 2 diabetes has become a worldwide epidemic. It is characterised by insulin resistance in major metabolic tissues, and failure of -pancreatic cells to compensate for this abnormality. Insulin resistance is recognised as an early event in the pathogenesis of type 2 diabetes. Although the precise factors that lead to insulin resistance have not been elucidated fully, there is strong association between insulin resistance and lipid accumulation, in particular lipotoxic fatty acid metabolites in insulin-target tissues. Most recently, evidence has been presented to link abnormal fatty acid accumulation in muscle with reduced mitochondrial activity. However it was unclear if these aberrations are causally related to the development of insulin resistance and type 2 diabetes. The two major pathophysiological abnormalities that underlie type 2 diabetes have long been viewed to require two separate pathogenic processes. The resolution of type 2 diabetes after bariatric surgery has allowed the elucidation of the sequence of events that lead to the restoration of normal metabolism, paving the way for a new understanding of type 2 diabetes as a metabolic state precipitated by a single cause of chronic excess intra-organ lipid accumulation. Magnetic resonance technique provides a non-invasive way to evaluate metabolism in both normal and pathological states. Specifically, 31P magnetic resonance spectroscopy allows the observation of real-time ATP synthesis as a direct measurement of mitochondrial activity. 13C magnetic resonance spectroscopy can be applied to assess muscle glycogen concentration. Both 1H magnetic resonance spectroscopy and magnetic resonance imaging can be used to evaluate intra-organ lipid concentration. Collectively, these innovative techniques offer safe and powerful approaches to study the role of skeletal muscle oxidative capacity and intra-organ fatty acid accumulation and metabolism in the pathogenesis of type 2 diabetes. This thesis presents data which lead to a simplified understanding of the aetiology and pathogenesis of type 2 diabetes.The Wellcome Trust, Newcastle upon Tyne, MRC Biomedical Research Centre and Diabetes UK

Service Oriented Big Data Management for Transport

International audienceThe increasing power of computer hardware and the sophistication of computer software have brought many new possibilities to information world. On one side the possibility to analyse massive data sets has brought new insight, knowledge and information. On the other, it has enabled to massively distribute computing and has opened to a new programming paradigm called Service Oriented Computing particularly well adapted to cloud computing. Applying these new technologies to the transport industry can bring new understanding to town transport infrastructures. The objective of our work is to manage and aggregate cloud services for managing big data and assist decision making for transport systems. Thus this paper presents our approach to propose a service oriented architecture for big data analytics for transport systems based on the cloud. Proposing big data management strategies for data produced by transport infra‐ structures, whilst maintaining cost effective systems deployed on the cloud, is a promising approach. We present the advancement for developing the Data acquisition service and Information extraction and cleaning service as well as the analysis for choosing a sharding strategy