Conceptual, self-assembling graphene nanocontainers

We show that graphene nano-sheets, when appropriately functionalised, can form self-assembling nanocontainers which may be opened or closed using a chemical trigger such as pH or polarity of solvent. Conceptual design rules are presented for different container structures, whose ability to form and encapsulate guest molecules is verified by molecular dynamics simulations. The structural simplicity of the graphene nanocontainers offers considerable scope for scaling the capacity, modulating the nature of the internal environment, and defining the trigger for encapsulation or release of the guest molecule(s). This design study will serve to provide additional impetus to developing synthetic approaches for selective functionalisation of graphene

Cholesterol-cholate-butterfat diet offers multi-organ dysfunction in rats

Background: Comparable to commercial expensive high-fat diets, cholesterol-cholate-butterfat (CCB) diet has also been used to induce hyperlipidemia in rats. Our objective was to explore its influence on multiple organs. Consequence of fasting was also analysed.Methods: Rats in groups 1 and 2 received normal diet (ND) whereas groups 3 and 4 received CCB-diet. Food was withdrawn daily for two hours from groups 2 (ND-F) and 4 (CCB-F). Blood was collected at fourth and sixth week for biochemical estimation; Morris water maze was done in the sixth week for learning ability and memory; after which aortae were isolated for vascular reactivity.Results: Apart from hyperlipidemia, CCB also induced hyperglycemia with marked increase in hepatic enzymes: gamma-glutamyl transferase (GGT), alanine and aspartate aminotransferase (ALT and AST); and vascular biomarkers: uric acid (UA), phosphorus and alkaline phosphatase (ALP). Isolated aortae, pre-contracted with phenylephrine, were less responsive to acetylcholine indicating endothelial dysfunction--serum nitric oxide (NO) production was limited with subsequent inhibition of endothelial NO synthase. CCB diet also compromised learning ability. CCB-coupled fasting potentiated hyperlipidemia but prevented memory-loss.Conclusion: We introduce CCB-diet for multi-organ dysfunction in rats, and propose its use for research on cardiovascular diseases and associated manifestations involving immense interplay of integrated pathways

Solubility prediction for a soluble organic molecule via chemical potentials from density of states

While the solubility of a substance is a fundamental property of widespread significance, its prediction from first principles (starting from only the knowledge of the molecular structure of the solute and solvent) remains a challenge. Recently, we proposed a robust and efficient method to predict the solubility from the density of states of a solute-solvent system using classical molecular simulation. The efficiency, and indeed the generality, of the method has now been enhanced by extending it to calculate solution chemical potentials (rather than probability distributions as done previously), from which solubility may be accessed. The method has been employed to predict the chemical potential of Form 1 of urea in both water and methanol for a range of concentrations at ambient conditions and for two charge models. The chemical potential calculations were validated by thermodynamic integration with the two sets of values being in excellent agreement. The solubility determined from the chemical potentials for urea in water ranged from 0.46 to 0.50 mol kg−1, while that for urea in methanol ranged from 0.62 to 0.85 mol kg−1, over the temperature range 298–328 K. In common with other recent studies of solubility prediction from molecular simulation, the predicted solubilities differ markedly from experimental values, reflecting limitations of current forcefields

Polymorphic Phase Transitions:Macroscopic Theory and Molecular Simulation

Transformations in the solid state are of considerable interest, both for fundamental reasons and because they underpin important technological applications. The interest spans a wide spectrum of disciplines and application domains. For pharmaceuticals, a common issue is unexpected polymorphic transformation of the drug or excipient during processing or on storage, which can result in product failure. A more ambitious goal is that of exploiting the advantages of metastable polymorphs (e.g. higher solubility and dissolution rate) while ensuring their stability with respect to solid state transformation. To address these issues and to advance technology, there is an urgent need for significant insights that can only come from a detailed molecular level understanding of the involved processes. Whilst experimental approaches at best yield time- and space-averaged structural information, molecular simulation offers unprecedented, time-resolved molecular-level resolution of the processes taking place. This review aims to provide a comprehensive and critical account of state-of-the-art methods for modelling polymorph stability and transitions between solid phases. This is flanked by revisiting the associated macroscopic theoretical framework for phase transitions, including their classification, proposed molecular mechanisms, and kinetics. The simulation methods are presented in tutorial form, focusing on their application to phase transition phenomena. We describe molecular simulation studies for crystal structure prediction and polymorph screening, phase coexistence and phase diagrams, simulations of crystal-crystal transitions of various types (displacive/martensitic, reconstructive and diffusive), effects of defects, and phase stability and transitions at the nanoscale. Our selection of literature is intended to illustrate significant insights, concepts and understanding, as well as the current scope of using molecular simulations for understanding polymorphic transitions in an accessible way, rather than claiming completeness. With exciting prospects in both simulation methods development and enhancements in computer hardware, we are on the verge of accessing an unprecedented capability for designing and developing dosage forms and drug delivery systems in silico, including tackling challenges in polymorph control on a rational basis

Almond supplementation reduces serum uric acid in coronary artery disease patients: a randomized controlled trial.

Objective Elevated serum uric acid (UA), a biomarker of renal insufficiency, is also an independent prognostic marker for morbidity in coronary artery disease (CAD) and poses serious health risks. This study reports the effect of almond consumption on UA in CAD patients. Study design A randomized controlled clinical trial was conducted with three groups: no-intervention (NI), Pakistani almonds (PA) or American almonds (AA). Patients were recruited from the Cardiology Clinics, Aga Khan University Hospital. Two follow-ups were scheduled at week-6 and week-12. 150 patients were randomly divided in three groups (50 per group). NI was not given almonds, whereas the PA and AA were given Pakistani and American almond varieties (10 g/day), respectively; with instruction to soak overnight and eat before breakfast. Results Almonds supplementation significantly reduced (p \u3c 0.05) serum UA among groups, and over time. At week-6, UA concentrations were -13 to -16 % less in PA and AA; at week-12 the concentrations were -14 to -18 % less, compared to NI. Systolic and diastolic blood pressure and body weights of the participants remained fairly constant among all the groups. Conclusion Almonds (10 g/day), eaten before breakfast, reduces serum UA in CAD patients. Prevention of hyperuricemia can confer protection from kidney and vascular damage and if extrapolated for general population, dietary almonds can offer grander health benefit. Trial is registered at Australian New Zealand Clinical trial registry as ACTRN12614000036617

Frequency of types of parturition and their relationship with maternal characteristics: a cross-sectional analysis

Background: The pathways that are involved for the duration of pregnancy and type of parturition are extremely complex, involving maternal as well as fetal systems. The objective of this study was to determine the frequency of types of parturition and their relationship with maternal characteristics among pregnant female patients.Methods: A cross-sectional survey using a non-probability convenient sampling technique was conducted among 195 healthy pregnant females at Obstetrics and Gynaecological Department of Hamdard Hospital, Karachi, from 1st March 2019 to 31st August 2019. After taking written informed consent from the participants, the relevant data were gathered with the help of a structured questionnaire designed specifically for the study. Statistical package for social sciences was used for data entry while the chi-square test was applied for inferential analysis. The duration of the study was six months. Data were entered and analyzed using Statistical Package for Social Sciences version 20.0. Descriptive analysis was performed by generating means and standard deviations for continuous variables while frequencies and percentages for categorical variables. A Chi-square test was applied to perform the inferential analysis while the significance level was set at 0.05.Results: A total of 195 pregnant females were included in the study, whose mean age was 29.29±5.22 years. The study results showed that BMI before pregnancy (p=0.021), rest is taken during pregnancy (p=0.034) and gravida status (p=0.047) were all significantly associated with the type of parturition among the study participants, but spacing in pregnancies and parity were not.Conclusions: Maternal characteristics were found to be significantly associated with the type of parturition among pregnant females. For gynecologists the maternal characteristics identified in this study may serve as a useful indicator of the type of parturition expected in their patients

Directing self-assembly to grow adaptive physical structures

Additive manufacturing technologies offer exciting opportunities to rethink the process of designing and fabricating physical structures. This paper outlines initial work that seeks to extend existing AM capabilities, creating physically adaptive structures by exploiting processes of self-assembling materials. The paper details an investigation of self-assembling structures that can respond to different conditions by adapting their physical properties over time. The process uses electrolysis of seawater to demonstrate a proof-of concept of tuneable material structures, via crystal growth. Results demonstrate an aggregation-based multi-material system that is sensitive to changing environmental conditions. Material properties of grown structures have been analysed and illustrate that different materials can be created from an abundant base material (seawater) by manipulating environmental conditions (i.e. electrical current). It is found that turbulence is a useful property within these kinds of systems and that the physical properties of cathode scaffold structures have a significant impact in controlling material properties and resolution

Rare Complication of Percutaneous Nephrolithotomy: Nephrostomy Tube in Renal Vein and Inferior Vena Cava

Percutaneous nephrolithotomy (PCNL) is considered as the gold standard treatment for renal stones > 2cm. We encountered a patient who underwent PCNL and inadvertently placement ofpercutaneous nephrostomy tube in the inferior vena cava through the left renal vein from the left Kidney.There was profuse bleeding during the procedure (PCNL), and the procedure was abandoned by placing a nephrostomy tube. PNT was removed after 04 days in two steps without any bleeding

Study abroad benefits and graduates employability: Asian International Mobility for Students Programme (AIMS): Malaysia

The multitude of existing research conducted within the field of study abroad generally reinforces the popular understanding that the practice not only broadens the mind, provides valuable experiences and enhances stagnating perspectives, but also contributes to a skillset that is becoming increasingly necessary for success in the globally focused world of today. Despite the evidence supporting their effectiveness, relatively few undergraduate students of Malaysia choose to participate in some form of study abroad programmes especially to the ASEAN countries. The following analysis will examine the potential reasoning of why this is so. In this context the focus is on the mobility programme on the short-term exchange and study abroad issues. Through the survey, this research examined the attitudes and inhibitions of undergraduate university students as they relate to studying abroad and to what extent these perceptions fall in line with the escalating importance of employability. Used as an exemplifying case of Asian Mobility for Students Programmes (AIMS), ten participating public universities under the AIMS-Malaysia furnished the sample of participants used in this study. Factors such as a student’s previous international travel experience and awareness of available programmes are seen to influence these perceptions to some degree. The students highlighted the benefits of studying abroad as to have better understanding of cultural differences and new friends share the same highest mean. The students also developed their soft skills by being more independent, confident and improve their problem-solving skills. In addition, they also have better communication, self-assessment and personal skills. The finding also showed that the most important criteria that the alumni being hired for their first job after graduation are communication skills, high adaptability, analytical thinking and problem solving. These findings corroborate international student mobility programmes whilst providing additional insight through student testimony. Indeed, AIMS programme leverages the competency and employability of students, hence contributes to producing global citizens and ASEAN harmonization

Study Abroad Benefits and Graduates Employability: Asian International Mobility for Students Programme (AIMS): Malaysia Kebaikan Pengajian di Luar Negara dan Kebolehpasaran Graduan: Asian International Mobility for Students (AIMS): Malaysia

The multitude of existing research conducted within the field of study abroad generally reinforces the popular understanding that the practice not only broadens the mind, provides valuable experiences and enhances stagnating perspectives, but also contributes to a skillset that is becoming increasingly necessary for success in the globally focused world of today. Despite the evidence supporting their effectiveness, relatively few undergraduate students of Malaysia choose to participate in some form of study abroad programmes especially to the ASEAN countries. The following analysis will examine the potential reasoning of why this is so. In this context the focus is on the mobility programme on the short-term exchange and study abroad issues. Through the survey, this research examined the attitudes and inhibitions of undergraduate university students as they relate to studying abroad and to what extent these perceptions fall in line with the escalating importance of employability. Used as an exemplifying case of Asian Mobility for Students Programmes (AIMS), ten participating public universities under the AIMS-Malaysia furnished the sample of participants used in this study. Factors such as a student’s previous international travel experience and awareness of available programmes are seen to influence these perceptions to some degree. The students highlighted the benefits of studying abroad as to have better understanding of cultural differences and new friends share the same highest mean. The students also developed their soft skills by being more independent, confident and improve their problem-solving skills. In addition, they also have better communication, self-assessment and personal skills. The finding also showed that the most important criteria that the alumni being hired for their first job after graduation are communication skills, high adaptability, analytical thinking and problem solving. These findings corroborate international student mobility programmes whilst providing additional insight through student testimony. Indeed, AIMS programme leverages the competency and employability of students, hence contributes to producing global citizens and ASEAN harmonization