9 research outputs found
Modeling and Forecasting of Energy Scenario in Pakistan with Application of Decentralized Energy Planning
Get PDFThe global energy demand has enlarged in recent years as a result of industrial development and population growth. This scenario has even intensified in Pakistan affecting industrial as well as domestic and agriculture sectors, causing 2-3% of GDP loss annually. According to Pakistan Energy Year Book 2012, Pakistan generation capacity being 95365GWh is far greater than the consumption 76,761GWh, indicating that these power-outages are not because of lack of generation capacity but improper energy management. The current pattern of centralized electricity based on costly imported oil, has resulted in inequities, debts and high transmission losses. Therefore, a change in overall energy mix has to be made considering requirements and regional availability of competent resources which can be possible by introducing Decentralized Energy Planning in power policy. In the present research work a comprehensive energy model for Pakistan has been created using LEAP, identifying the loop-holes in system and presenting possible remedies for the current energy crunch
A 3-D printed mini-hydrocyclone for high throughput particle separation: application to primary harvesting of microalgae
No full textThe separation of micro-sized particles in a continuous flow is crucial part of many industrial processes, from biopharmaceutical manufacturing to water treatment. Conventional separation techniques such as centrifugation and membrane filtration are largely limited by factors such as clogging, processing time and operation efficiency. Microfluidic based techniques have been gaining great attention in recent years as efficient and powerful approaches for particle-liquid separation. Yet the production of such systems using standard micro-fabrication techniques is proven to be tedious, costly and have cumbersome user interfaces, which all render commercialization difficult. Here, we demonstrate the design, fabrication and evaluation based on CFD simulation as well as experimentation of 3D printed miniaturized hydrocyclones with smaller cut-size for high-throughput particle/cell sorting. The characteristics of the mini-cyclones were numerically investigated using computational fluid dynamics (CFD) techniques previously revealing that reduction in the size of the cyclone results in smaller cut-size of the particles. To showcase its utility, high-throughput algae harvesting from the medium with low energy input is demonstrated for the marine microalgae Tetraselmis suecica. Final microalgal biomass concentration was increased by 7.13 times in 11 minutes of operation time using our designed hydrocyclone (HC-1). We expect that this elegant approach can surmount the shortcomings of other microfluidic technologies such as clogging, low-throughput, cost and difficulty in operation. By moving away from production of planar microfluidic systems using conventional microfabrication techniques and embracing 3D printing technology for construction of discrete elements, we envision 3D-printed mini-cyclones can be part of a library of standardized active and passive microfluidic components, suitable for particle-liquid separation.sponsorship: D. Vandamme is a postdoctoral Researcher funded by the Research Foundation - Flanders Belgium (FWO - 12D8917N). This work was performed (in part) at the NSW and South Australian node of the Australian National Fabrication Facility under the National Collaborative Research Infrastructure Strategy to provide nano- and micro-fabrication facilities for Australia's researchers. (Research Foundation - Flanders Belgium|FWO - 12D8917N)status: Publishe
Optimizing the phosphorus use in cotton by using CSM-CROPGRO-cotton model for semi-arid climate of Vehari-Punjab, Pakistan
Get PDFRahman, Muhammad Habib ur/0000-0002-2823-9959; Jabran, Khawar/0000-0001-8512-3330; Hakeem, Khalid Rehman/0000-0001-7824-4695; Amin, Asad/0000-0003-2242-8377; Ata-Ul-Karim, Syed Tahir/0000-0001-5233-4502; Jatoi, Ghulam Hussain/0000-0002-7266-1567; Rehmani, M.I.A./0000-0001-7922-1233; Bajwa, Ali/0000-0002-7171-3118; Nadeem, Muhammad/0000-0002-7426-1196; Ata-Ul-Karim, Syed Tahir/0000-0001-5233-4502; Ameen, Asif/0000-0002-3982-7000; Islam, Faisal/0000-0002-1471-1570WOS: 000397013000067PubMed: 28054268Crop nutrient management is an essential component of any cropping system. With increasing concerns over environmental protection, improvement in fertilizer use efficiencies has become a prime goal in global agriculture system. Phosphorus (P) is one of the most important nutrients, and strategies are required to optimize its use in important arable crops like cotton (Gossypium hirsutum L.) that has great significance. Sustainable P use in crop production could significantly avoid environmental hazards resulting from over-P fertilization. Crop growth modeling has emerged as an effective tool to assess and predict the optimal nutrient requirements for different crops. In present study, Decision Support System for Agro-technology Transfer (DSSAT) sub-model CSM-CROPGRO- Cotton-P was evaluated to estimate the observed and simulated P use in two cotton cultivars grown at three P application rates under the semi-arid climate of southern Punjab, Pakistan. The results revealed that both the cultivars performed best at medium rate of P application (57 kg ha(-1)) in terms of days to anthesis, days to maturity, seed cotton yield, total dry matter production, and harvest index during 2013 and 2014. Cultivar FH-142 performed better than MNH-886 in terms of different yield components. There was a good agreement between observed and simulated days to anthesis (0 to 1 day), days to maturity (0 to 2 days), seed cotton yield, total dry matter, and harvest index with an error of -4.4 to 15%, 12-7.5%, and 13-9.5% in MNH-886 and for FH-142, 4-16%, 19-11%, and 16-8.3% for growing years 2013 and 2014, respectively. CROPGRO-Cotton-P would be a useful tool to forecast cotton yield under different levels of P in cotton production system of the semi-arid climate of Southern Punjab.Government of Australia [4915_2015]; Higher Education Commission (HEC) of PakistanHigher Education Commission of PakistanThe first author is grateful to the International Global Change Institute (IGCI) Hamilton, New Zealand, for providing the software (SimCLIM2013) and the required climatic dataset for future projections with for southern Punjab, Pakistan. The first author is thankful to Prof. Dr. Gerrit Hoogenboom (Ex-Director, AgWeatherNet, Washington State University, USA; Currently: University of Florida-USA), for his technical guidance and support during the entire period of study and modeling work. Furthermore, first author is highly thankful from NASA for weather data of respective years (which was obtained from website http://power.larc.nasa.gov/cgi-bin/cgiwrap). The corresponding author (Wajid NASIM) is highly thankful to Government of Australia, for Endeavor Research Award/Fellowship (No. 4915_2015) to The Commonwealth Scientific and Industrial Research Organization (CSIRO), Sustainable Agriculture, National Research Flagship, Toowoomba-QLD 4350, Australia. Furthermore, co-authors (Wajid NASIM and Shakeel AHMAD) are highly thankful for Higher Education Commission (HEC) of Pakistan for partial funding
Author Correction: Influence of natural and non‑natural diets on the fitness and rearing of Pectinophora gossypiella Saunders
No full textMicrofluidic Actuation via 3D-Printed Molds toward Multiplex Biosensing of Cell Apoptosis
No full textMultiplexed analysis of biochemical
analytes such as proteins,
enzymes, and immune products using a microfluidic device has the potential
to cut assay time, reduce sample volume, realize high-throughput,
and decrease experimental error without compromising sensitivity.
Despite these huge benefits, the need for expensive specialized equipment
and the complex photolithography fabrication process for the multiplexed
devices have, to date, prevented widespread adoption of microfluidic
systems. Here, we present a simple method to fabricate a new microfluidic-based
multiplexed biosensing device by taking advantage of 3D-printing.
The device is an integration of normally closed (NC) microfluidic
valving units which offer superior operational flexibility by using
PDMS membrane (E ∼ 1–2 MPa) and require
minimized energy input (1–5 kPa). To systematically engineer
the device, we first report on the geometrical and operational analysis
of a single 3D-printed valving unit. Based on the characterization,
we introduce a full prototype multiplexed chip comprising several
microfluidic valves. The prototype offersfor the first time
in a 3D-printed microfluidic devicethe capability of on-demand
performce of both a sequential and a parallel biochemical assay. As
a proof of concept, our device has been used to simultaneously measure
the apoptotic activity of 5 different members of the caspase protease
enzyme family. In summary, the 3D-printed valving system showcased
in this study overcomes traditional bottlenecks of microfabrication,
enabling a new class of sophisticated liquid manipulation required
in performing multiplexed sensing for biochemical assays
Microfluidic Actuation via 3D-Printed Molds toward Multiplex Biosensing of Cell Apoptosis
No full textMultiplexed analysis of biochemical
analytes such as proteins,
enzymes, and immune products using a microfluidic device has the potential
to cut assay time, reduce sample volume, realize high-throughput,
and decrease experimental error without compromising sensitivity.
Despite these huge benefits, the need for expensive specialized equipment
and the complex photolithography fabrication process for the multiplexed
devices have, to date, prevented widespread adoption of microfluidic
systems. Here, we present a simple method to fabricate a new microfluidic-based
multiplexed biosensing device by taking advantage of 3D-printing.
The device is an integration of normally closed (NC) microfluidic
valving units which offer superior operational flexibility by using
PDMS membrane (E ∼ 1–2 MPa) and require
minimized energy input (1–5 kPa). To systematically engineer
the device, we first report on the geometrical and operational analysis
of a single 3D-printed valving unit. Based on the characterization,
we introduce a full prototype multiplexed chip comprising several
microfluidic valves. The prototype offersfor the first time
in a 3D-printed microfluidic devicethe capability of on-demand
performce of both a sequential and a parallel biochemical assay. As
a proof of concept, our device has been used to simultaneously measure
the apoptotic activity of 5 different members of the caspase protease
enzyme family. In summary, the 3D-printed valving system showcased
in this study overcomes traditional bottlenecks of microfabrication,
enabling a new class of sophisticated liquid manipulation required
in performing multiplexed sensing for biochemical assays
Microfluidic Actuation via 3D-Printed Molds toward Multiplex Biosensing of Cell Apoptosis
No full textMultiplexed analysis of biochemical
analytes such as proteins,
enzymes, and immune products using a microfluidic device has the potential
to cut assay time, reduce sample volume, realize high-throughput,
and decrease experimental error without compromising sensitivity.
Despite these huge benefits, the need for expensive specialized equipment
and the complex photolithography fabrication process for the multiplexed
devices have, to date, prevented widespread adoption of microfluidic
systems. Here, we present a simple method to fabricate a new microfluidic-based
multiplexed biosensing device by taking advantage of 3D-printing.
The device is an integration of normally closed (NC) microfluidic
valving units which offer superior operational flexibility by using
PDMS membrane (E ∼ 1–2 MPa) and require
minimized energy input (1–5 kPa). To systematically engineer
the device, we first report on the geometrical and operational analysis
of a single 3D-printed valving unit. Based on the characterization,
we introduce a full prototype multiplexed chip comprising several
microfluidic valves. The prototype offersfor the first time
in a 3D-printed microfluidic devicethe capability of on-demand
performce of both a sequential and a parallel biochemical assay. As
a proof of concept, our device has been used to simultaneously measure
the apoptotic activity of 5 different members of the caspase protease
enzyme family. In summary, the 3D-printed valving system showcased
in this study overcomes traditional bottlenecks of microfabrication,
enabling a new class of sophisticated liquid manipulation required
in performing multiplexed sensing for biochemical assays
Performance Analysis of a Directly Coupled Solar Powered Thermoelectric Refrigeration System
No full textFood items, medicines and other perishables are considerably sensitive to temperature and environmental conditions. Storage and transportation of these items without affecting their quality is one of the acute challenges all over the world. The method of refrigeration is used to keep these items below atmospheric temperature. It is an energy intensive process and to meet these energy requirements, electric power is commonly used. As the electricity crisis and prices are increasing day by day, it has established a thought provoking ideology to utilize solar energy for refrigeration processes and improving their performance in this regard. Photovoltaic Powered Thermoelectric Refrigerator is a special type of refrigerator which uses solar energy instead of conventional electrical energy and is based on the principles Peltier effect to create a cold side and a hot side. The cold side of the module is used for the cooling of refrigerator space while the heat from the hot side is rejected to ambient by using heat sinks and fans. The present work for the experimentation of Solar Thermoelectric Refrigeration unit was carried out at the Department of Mechanical Engineering, University of Engineering & Technology Lahore-Pakistan at KSK Campus. The results showed that at an ambient temperature below that of 25ºC, the unit could maintain the temperature in the refrigerator space at about 0ºC. The maximum COP recorded was about 0.65. It has been further analyzed that the temperature gradient of hot and cold sides of the thermoelectric module and solar irradiance greatly affects the system performance. An optimum value of solar insolation rate let the cooling production and COP to achieve maximum value. The refrigerator would be potential for cold storage in remote and outdoor conditions where electric power supply is absent. It has the advantages of being portable, small, reliable, lightweight, noiseless and low cost in mass production
SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study
No full textBackground: Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling.
Methods: The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18-49, 50-69, 70 or more years) and type of surgery. Best- and worst-case scenarios were used to describe uncertainty.
Results: NNVs were more favourable in surgical patients than the general population. The most favourable NNVs were in patients aged 70 years or more needing cancer surgery (351; best case 196, worst case 816) or non-cancer surgery (733; best case 407, worst case 1664). Both exceeded the NNV in the general population (1840; best case 1196, worst case 3066). NNVs for surgical patients remained favourable at a range of SARS-CoV-2 incidence rates in sensitivity analysis modelling. Globally, prioritizing preoperative vaccination of patients needing elective surgery ahead of the general population could prevent an additional 58 687 (best case 115 007, worst case 20 177) COVID-19-related deaths in 1 year.
Conclusion: As global roll out of SARS-CoV-2 vaccination proceeds, patients needing elective surgery should be prioritized ahead of the general population
