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An ALS diagnosis is devastating. The harsh realities of the disease reinforce the need for innovative research and a stronger Canadian health-care system. But Claudette Sturk, diagnosed with ALS in [...]

In December 2015, Tings Chak stood among protesters outside the Toronto Police Service's headquarters, holding a banner that read, 'NO STATUS CHECKS IN A SANCTUARY CITY.' The protest--organized after an [...]

In order to find an economic and effective water control method for horizontal wells in deep sea bottom-water gas reservoirs, we prepared modified coated gravel. Based on this, wear resistance, temperature resistance and water plugging capacity (WPC) tests were carried out on the coated gravel. Then, experiments were carried out using the 3D simulation device for the development of large-scale bottom-water gas reservoirs to compare the development effects of horizontal wells packed with conventional gravel and coated gravel in deepsea bottom-water gas reservoirs. And the following research results were obtained. First, the upper limit of temperature resistance of the gravel coating is 240 °C and the gravel packing speed can reach 4.48 m/s, which is 8 times the average flow velocity of gravel packing in actual open hole sections. Second, as the permeability of the coated gravel packing layer increases, its WPC gets weak. When the permeability is lower than 1500 mD and the displacement pressure difference is lower than 0.6 MPa, the WPC of the coated gravel packing layer is between 0.17 and 0.68. Third, the coated gravel layer functions as gas permeability and water plugging, so the horizontal well technology with coated gravel packing can reduce the flow capacity of water phase breaking into the dominant flow passage, so as to delay the rise of water production of gas well and prolong the gas production time. In this way, the gas recovery factor of bottom-water gas reservoir can be increased effectively. In conclusion, this technology has the function of spontaneous selective water plugging, i.e., “water plugging in case of water and gas permeability in case of gas”, and its technical and economic advantages are remarkable, which can provide a new idea for the water-control development of deepsea bottom-water gas reservoirs.

Idiopathic pulmonary fibrosis, an idiopathic interstitial lung disease with high mortality, remains challenging to treat due to the lack of clinically approved lung-targeting drugs. Herein, we present PDIC-DPC, a perylenediimide derivative that exhibits superior lung-selective enrichment. PDIC-DPC forms nanocomposites with plasma proteins, including fibrinogen beta chain and vitronectin, which bind to pulmonary endothelial receptors for lung-specific accumulation. Moreover, PDIC-DPC significantly suppresses transforming growth factor beta1 and activates adenosine monophosphate-activated protein kinase. As a result, compared to existing therapeutic drugs, PDIC-DPC achieves superior therapeutic outcomes, evidenced by the lowest Ashcroft score, significantly improved pulmonary function, and an extended survival rate in a bleomycin-induced pulmonary fibrosis model. This study elucidates the lung-selective enrichment of assembled prodrug from biological perspectives and affords a platform enabling therapeutic efficiency on idiopathic pulmonary fibrosis.

Heavy oil reservoirs generally have strong non-homogeneity. In this paper, firstly, physical simulation experiments of steam stimulation in straight wells were carried out to analyze the effects of the composite system of foaming agents and CO2on the temperature field, oil production and water content. Secondly, the effects of foaming agents and CO2on the steam stimulation efficiency of horizontal wells were analyzed using the horizontal well sand filling model. Finally, steam drive physical simulation experiments were conducted to analyze the effects of foaming agent and CO2segment plug on formation pressure, recovery and water content. Results show that: after injecting CO2+ foaming agent into the vertical well for several cycles, the temperature field affected area increased significantly; Compared with foaming agent: CO2= 2:1, for foaming agent: CO2= 1:1, the swept area is more uniform and the recovery factor is higher.

Tight oil is an important and potential reservoir in future China. Drawn from the successful exploration of tight oil in North America, tight oil exploration is now in progress in China. In this paper, we surveyed the tight oil exploration status and challenges, as well as the tight reservoir properties in China, including source rocks, lithology, physical properties and pressure coefficient. The process of pilot test and key technologies are analyzed, while it is still urgent to improve tight oil study and the production mode. We concluded that there are 4 aspects, which are geological features, energy supplement for formation, engineering and technical management innovation, should be improved, and national policy support for tight oil is another key point for successful exploration.

Both wettability alteration and low interfacial tension (IFT) are important mechanisms of surfactants for enhancing oil recovery. In the imbibition process, surfactant solution invades the matrix, lowering IFT and altering the contact angle; these factors change the distribution of oil as well as the magnitude and direction of capillary force. Although a lot of research has been done in modeling countercurrent imbibition, less attention has been paid to comparing which effect plays a more important role in the imbibition process. A mechanistic model was used to study the surfactant solution imbibition process in porous media with subnanometer and nanometer capillaries, and the approximated diffusion coefficient was used to simplify the calculation. The simulated calculation demonstrates that, in contrast to low IFT, the change in wettability is the major mechanism for improving tight rock imbibition recovery, and this confirms that the change in wettability contributes more than lower IFT to the ultimate imbibition recovery.

Underground coal gasification (UCG) is widely regarded as a clean coal technology that holds enormous potential to decarbonize the world's coal industry. It converts coal underground into combustible syngas through a set of complex physiochemical events. Experimental and numerical efforts over the past century have contributed to the development of UCG around the world; however, tapping the world's deep-situated coal resources with UCG requires substantial contributions from numerous high-quality researchers. To facilitate effective engagement, this paper will provide a background on where to start if one wishes to undertake UCG modelling. First, a brief description of the fundamental phenomena involved in UCG is given. Then, a succinct introduction of the widely used modelling software is rendered, followed by a description of UCG studies to provide insight how to tune the various software packages for modelling UCG and where their strengths lie. This paper shall serve as guidance to new UCG modellers.

Renewable osmotic energy shows great potential in mitigating the global energy crisis for its huge reserves. Ionic polymer hydrogels with intrinsic low resistance are promising candidates for osmotic energy harvesting in membrane-based process. However, ionic polymer hydrogels are prone to over-expand in aqueous solution, resulting in poor mechanical strength and ionic selectivity. Here, we propose a physically confined strategy with wood vessel to inhibit the swelling of ionic polymer hydrogel, to construct highly stable hydrogel-based ion-selective membrane. This anti-swelling membrane shows high ionic selectivity of 0.857 and corresponding generator delivers an efficiency of 25.5% with the power density of 8.5 W m−2under a 50-fold salinity gradient (NaCl) simulating sea/river junction environment. This work provides a new strategy for preparing hydrogel-based ion-selective membrane, which has broad application prospects in the fields of osmotic energy collection, electrodialysis, liquid flow battery and so on.

The article presents profile and efforts of artist Tings Chak to raise issues of migrant detentions with overstayed visa and without migration documents in Toronto, Ontario. Topics discussed include Chak's novel, "Undocumented: The Architecture of Migrant Detention," the hunger strike by detainees regarding the conditions in which they were held at Central East Correctional Centre in Lindsay, Ontario in 2013 and the criticism of the criminal justice system of Canada by Chak.

Solar desalination shows great potential in dealing with global water scarcity. A multistage passive solar distiller with thermal localization is especially attractive for its high-water yield. However, achieving long-term stability in large-scale devices remains a challenge because of the easy accumulation of crystallized salt inside the distiller. Here, we reported that the Marangoni effect can drive crystallized salt away along a long distance in a capillary wick, which endow the multistage passive solar distiller with the ability of salt-rejecting. In a 36 h continuous testing, the salinity of the distillation zone is limited below 12 wt % and crystallized salt only accumulates outside the device. The water yield is about 1.7 kg m–2h–1in a three-stage device, with a solar-to-vapor conversion efficiency of 114% under one sun. This novel design proves a new principle for high efficiency and long-term stable solar desalination.

Passive solar multistage stiller with heat localization has shown great potential in wastewater purification and seawater desalination due to its ultrahigh solar-to-vapor conversion ability. However, achieving high water yield with long stability remains a great challenge because of the salt clog. Here, we demonstrated a photovoltaic-multistage stiller (PV-MS) with excellent salt-rejecting ability, even when dealing with hypersaline waters. The solar energy is converted to electricity and heat by a commercial photovoltaic panel and the waste heat subsequently drives the passive multistage stiller. The capillary wick and the crystalized salt at the edge of the wick form a siphon channel and the crystalized salt was rinsed intermittently by the siphon action, thereby avoiding salt clog. Thus, we achieved simultaneous electricity, water and salt collection in the integrated photovoltaic-thermal utilization system with long-term stability. Under one sun, the water yield of a five-stage stiller was about 1.17 kg m−2h−1with electricity output of 97 W m−2and salt collection of 1.02 kg m−2d−1when desalinating hypersaline NaCl solution of 170 g/L. We envision that such a technology can help full use of solar energy in desalinating high-salinity waters with long term stability and is greatly promising at the water-energy nexus.