Manual pressing of nannochloropsis oculata dried biomass for enhanced lipid extraction

Microalgae offer significant potential to produce high value products and biofuels, whilst simultaneously being used to bio-remediate water or capture carbon dioxide (CO2). Microalgal cell disruption processes are often necessary to increase lipid extraction from microalgae before conventional solvent extraction processes are used to isolate lipids. The extracted lipids can be processed to produce biofuels. The combinations of hydraulic pressing with liquid nitrogen (LN2) treatment were applied to samples of dried Nannochloropsis oculata in the presented study to enhance the cellular destruction and lipid yields. The results indicated higher lipid extraction with LN2 treatment (0.159 g/g dry algae) compared to the LN2 untreated samples (0.070 g/g dry algae). The corresponding cell disruptions were found to be seventy-eight and fifty percent, respectively, at the same 10 bar (145 psi) pressure level. The control sample (without any treatment) lipid yield was 0.006 g/g dry algae, while the lipid yield varied between 0.192-0.213 g/g dry algae with LN2 treated biomass with pressure loadings of 70-100 bar (1015-1450 psi) and with a corresponding cell disruption of 93-98 percent. The presence of palmitate, oleate and linoleate found in the fatty acid methyl ester composition of the extracted lipids, shows a favourable profile to produce biodiesel

Potential for Blue-Gray Water Trade-offs for Irrigation in Small Towns of Pakistan: A Case Study of Farmers' Costs and Benefits in Haroonabad

The growing demand and the competition for fresh water in various sectors suggest that the irrigated agriculture will have to release freshwater for more important and valuable uses. This implies that other options would need to be identified to meet water demands for agriculture. Meeting irrigation requirements through non-conventional water sources is one of the options for agricultural uses. Gray water use for irrigation, a pervasive practice in urban and peri-urban areas of many developing countries, could be one of the solutions. The debate on wastewater irrigation from an environmental point of view is already on, focussing more on human and environmental “safety” aspects. The “value” aspect of the wastewater irrigation remains neglected, however. The irrigation users of untreated wastewater in many parts of the world had already traded off and revealed their preference for gray over blue water decades ago, when the water supply systems in towns and cities were set up. Why they would do it despite the high environmental and health risks associated with its use needs an answer. The paper documents the costs and benefits of wastewater irrigation from users’ point of view, and assesses the potential for real blue water savings in a small town setting in the southern Punjab, Pakistan. The data presented in the paper suggest that wastewater irrigation does lead to blue water savings, and it is profitable for farmers. While its potential is not fully exploited, more focus on appropriate approaches to physical and institutional aspects of wastewater disposal planning and management could make wastewater irrigation more productive, profitable, and safe for individuals as well as for the society as a whole.

Cancer biomarker development from basic science to clinical practice

The amount of published literature on biomarkers has exponentially increased over the last two decades. Cancer biomarkers are molecules that are either part of tumour cells or secreted by tumour cells. Biomarkers can be used for diagnosing cancer (tumour versus normal and differentiation of subtypes), prognosticating patients (progression free survival and overall survival) and predicting response to therapy. However, very few biomarkers are currently used in clinical practice compared to the unprecedented discovery rate. Some of the examples are: carcino-embryonic antigen (CEA) for colon cancer; prostate specific antigen (PSA) for prostate; and estrogen receptor (ER), progesterone receptor (PR) and HER2 for breast cancer. Cancer biomarkers passes through a series of phases before they are used in clinical practice. First phase in biomarker development is identification of biomarkers which involve discovery, demonstration and qualification. This is followed by validation phase, which includes verification, prioritisation and initial validation. More large-scale and outcome-oriented validation studies expedite the clinical translation of biomarkers by providing a strong ‘evidence base’. The final phase in biomarker development is the routine clinical use of biomarker. In summary, careful identification of biomarkers and then validation in well-designed retrospective and prospective studies is a systematic strategy for developing clinically useful biomarkers

Personal State and Emotion Monitoring by Wearable Computing and Machine Learning

One of the major scientific undertakings over the past few years has been exploring the interaction between humans and machines in mobile environments. Wearable computers, embedded in clothing or seamlessly integrated into everyday devices, have an incredible advantage to become the main gateway to personal health management. Current state of the art devices are capable in monitoring basic physical or physiological parameters. Traditional health systems procedures depend on the physical presence of the patient and a medical specialist that not only is a reason of overall costs but also reduces the quality of patients' lives, particularly elderly patients. Usually, patients have to go through the following steps for the traditional procedure: Firstly, patients need to visit the clinic, get registered at reception, wait for the turn, go to the lab for the physiological measurement, wait for the medical experts call, to finally receive feedback from the medical expert. In this work, we examined how to utilize existing technology in order to develop an e-health monitoring system especially for heart patients. This system should support the interaction between the patient and the physician even when the patient is not in the clinic. The supporting wearable health monitoring system WHMS should recognize physical activities, emotional states and transmit this information to the physician along with relevant physiological data; in this way patients do not need to visit the clinic every time for the physician's feed-back. After the discussion with medical experts, we identified relevant physical activities, emotional states and physiological data needed for the patients' examinations. A prototype of this concept for a health monitoring system of the proposed solution was implemented taking into account physical activities, emotional states and physiological data

Hard congestion limit of the dissipative Aw-Rascle system with a polynomial offset function

We study the Aw-Rascle system in a one-dimensional domain with periodic boundary conditions, where the offset function is replaced by the gradient of the function $\rho_{n}^{\gamma}$, where $\gamma \to \infty$. The resulting system resembles the 1D pressureless compressible Navier-Stokes system with a vanishing viscosity coefficient in the momentum equation and can be used to model traffic and suspension flows. We first prove the existence of a unique global-in-time classical solution for $n$ fixed. Unlike the previous result for this system, we obtain global existence without needing to add any approximation terms to the system. This is by virtue of a $n-$uniform lower bound on the density which is attained by carrying out a maximum-principle argument on a suitable potential, $W_{n} = \rho_{n}^{-1}\partial_{x}w_{n}$. Then, we prove the convergence to a weak solution of a hybrid free-congested system as $n \to \infty$, which is known as the hard-congestion model

Prospects of microalgal biodiesel production in Pakistan – a review

Biodiesel is an alternative, renewable, biodegradable and environmentally friendly fuel for transportation, with properties like petroleum-derived diesel, and can be used directly in a compression ignition engine without any modifications. The world's fossil fuel and crude oil reserves are going to dry up in the next few decades, but, contrariwise, an attractive, high quality, readily available and economically extractable oil from microalgae is a substitute feedstock to produce alternative biodiesel fuel for the transportation sector in the future. Microalgae have a higher biomass productivity (tons/hectare/year) and lipid yield (kg/kg of algal biomass) as compared to vegetable oil crops. To overcome the problem of energy deficiency in developing countries, like Pakistan, and boost their economic growth, alternative fuels are proving very important for environment-friendly and sustainable development, especially in the last few decades. Different research studies on microalgae cultivation, characterization of microalgae oil (lipids), and evaluations of its socio-economic feasibility to produce renewable biodiesel have been conducted in the past in Pakistan for its future prospects. This review paper includes the overall summary and compilation of the microalgae research conducted in Pakistan on biodiesel production and includes the algal biodiesel production cost analysis. The studies showed promising results for harnessing microalgae and using its lipids to produce biodiesel with favourable properties that were comparable to the conventional diesel in Pakistan. The information related to the microalgae research will help stakeholders and governmental organisations working in the renewable energy sector to consider its cultivation on a large scale, using waste water as a feedstock to produce biodiesel to meet the target set by the Government of Pakistan of using 10% blended biodiesel by the year 2025 in Pakistan

Mild pyrolysis of manually pressed and liquid nitrogen treated de‐lipid cake of nannochloropsis oculata for bioenergy utilisation

Due to the damaging impacts of continued use of fossil fuels, there is global interest in developing sustainable biofuel production to reduce society's dependency on carbon based energy resources. Microalgae cultivation can contribute to CO2 fixation from the atmosphere, while simultaneously producing a source of lipids from the biomass for third generation biodiesel fuel production. The residual de‐lipid cake left after lipid extraction can be treated with thermochemical techniques (such as mild pyrolysis) to produce solid biochar as an end product with a higher energy density and lower moisture content offering advantages for downstream processing or carbon sequestration. De‐lipid cake was produced by solvent extraction from Nannochloropsis oculata that had been manually pressed and/or treated with liquid nitrogen (LN2). The de‐lipid cake was thermally treated at 200 °C or 300 °C under partial vacuum in an oxygen free atmosphere. The solid biochar produced had a reduced moisture content (MC) resulting in a mass reduction of 25 and 66 wt % of de‐lipid cake without LN2 and treatment at 200 °C and 300 °C, respectively, while with LN2 treated cake the mass reduction was 23 and 67 wt % at 200 °C and 300 °C. The higher heating value of the control sample (without any manual pressing or LN2 treatment) was 23.35 MJ kg−1, while for the control sample it was enhanced to 26.82 and 30.56 MJ kg−1 with treatment at 200 °C and 300 °C, respectively. With LN2 treated samples with pressing the HHV was 21.98 MJ kg−1 for control sample as compared to 25.90 and 28.72 MJ kg−1 at 200 and 300 °C respectively, where the lower values were observed because of the lipid removal. The measured gas pressure developed, likely due to the production of CO2 and CH4 as major gases,, was 0.19 and 0.53 bars without LN2 treatment samples, while it was 0.13 and 0.58 bars with LN2. The torrefaction process (mild pyrolysis) energy analysis showed that the ER (energy ratio) without LN2 treatment sample with 0.485 at 200 °C was the highest and the lowest 0.407 energy ratio was found with LN2 treated sample at the higher treatment temperature (300 °C)

Potential for Blue-Gray Water Trade-offs for Irrigation in Small Towns of Pakistan: A Case Study of Farmers’ Costs and Benefits in Haroonabad

The growing demand and the competition for fresh water in various sectors suggest that the irrigated agriculture will have to release freshwater for more important and valuable uses. This implies that other options would need to be identified to meet water demands for agriculture. Meeting irrigation requirements through non-conventional water sources is one of the options for agricultural uses. Gray water use for irrigation, a pervasive practice in urban and peri-urban areas of many developing countries, could be one of the solutions. The debate on wastewater irrigation from an environmental point of view is already on, focussing more on human and environmental “safety” aspects. The “value” aspect of the wastewater irrigation remains neglected, however. The irrigation users of untreated wastewater in many parts of the world had already traded off and revealed their preference for gray over blue water decades ago, when the water supply systems in towns and cities were set up. Why they would do it despite the high environmental and health risks associated with its use needs an answer. The paper documents the costs and benefits of wastewater irrigation from users’ point of view, and assesses the potential for real blue water savings in a small town setting in the southern Punjab, Pakistan. The data presented in the paper suggest that wastewater irrigation does lead to blue water savings, and it is profitable for farmers. While its potential is not fully exploited, more focus on appropriate approaches to physical and institutional aspects of wastewater disposal planning and management could make wastewater irrigation more productive, profitable, and safe for individuals as well as for the society as a whole

THE USE OF BLOCKCHAIN IN THE MANAGEMENT OF COVID-19 VACCINE DATA

ABSTRACT - The ongoing COVID-19 pandemic has disrupted nearly every sector of the world economy. The recently discovered vaccine has promised a return to normalcy. Since traditional database storage systems can be tampered with quickly, the incorporation of blockchain would preclude the limitations of conventional database systems. This paper thus discusses the use of blockchain technology in managing the COVID-19 vaccine data to ensure credibility, safety, security, and transparency. Keywords - Blockchain technology, COVID-19 vaccine data, and vaccine supply chain

Measurement of NO2 indoor and outdoor concentrations in selected public schools of Lahore using passive sampler

Higher levels of NO2 are a danger to human health especially for children. A seven day study was carried to find out the ambient concentrations of NO2in 27 schools of Lahore with the help of passive samplers. In each school three sites were selected, viz: laboratory, corridor and outdoors. After 7 days exposure the tubes were subjected to spectrophotometric analysis. Results showed that the maximum values measured in laboratory, outdoor and corridors were 376µg/m3 , 222µg/m3 and 77µg/m3 . Minimum values for laboratory, outdoor and corridors were 10µg/m3 , 20µg/m3 and 8µg/m3 . Factors affecting these values were laboratory activities and proximity to main roads. These values were significantly higher than the standard values defined by EPA. Therefore children in schools were at risk of developing health complications