Impacts of future urban expansion on urban heat island effects during heatwave events in the city of Melbourne in southeast Australia

The city of Melbourne in southeast Australia is planning to expand urban areas substantially by the year 2050 and this expansion has the potential to alter the Urban Heat Island (UHI), that is, higher temperatures in urban areas as compared to surrounding rural areas. Moreover, Melbourne has been experiencing more frequent heatwaves for last two decades, and the intensity and duration of heatwaves is expected to increase in the future, which could exacerbate the UHI. This study evaluates the potential impacts of future urban expansion on the urban meteorology in Melbourne city during four of the most severe heatwave events during the period 2000–2009. Urban expansion is implemented as high‐density urban with a high urban fraction of 0.9 to investigate the maximum possible impact. Simulations are carried out using the Weather Research and Forecasting model coupled with the Single‐Layer Urban Canopy Model with current land‐use and future urban expansion scenarios. Urban expansion increases the near‐surface (2‐m) UHI (UHI2) by 0.75 to 2.80 °C and the skin‐surface UHI (UHIsk) by 1.9 to 5.4 °C over the expanded urban areas during the night, with no changes in existing urban areas. No substantial changes in UHI2 and UHIsk occur during the day over both existing and expanded urban areas. This is largely driven by changes in the storage heat flux, with an increase in storage heat at night and a decrease during the day; that is, excess storage heat accumulated during the day is released at night, which causes a slower decrease of near‐surface temperature and increase in the UHI. Urban expansion did not affect human thermal comfort (HTC) in existing urban areas and there were no marked differences in HTC between existing and expanded urban areas

Academic freedom: in justification of a universal ideal

This paper examines the justification for, and benefits of, academic freedom to academics, students, universities and the world at large. The paper surveys the development of the concept of academic freedom within Europe, more especially the impact of the reforms at the University of Berlin instigated by Wilhelm von Humboldt. Following from this, the paper examines the reasons why the various facets of academic freedom are important and why the principle should continue to be supported

SARS-CoV-2 infects the human kidney and drives fibrosis in kidney organoids

Kidney failure is frequently observed during and after COVID-19, but it remains elusive whether this is a direct effect of the virus. Here, we report that SARS-CoV-2 directly infects kidney cells and is associated with increased tubule-interstitial kidney fibrosis in patient autopsy samples. To study direct effects of the virus on the kidney independent of systemic effects of COVID-19, we infected human-induced pluripotent stem-cell-derived kidney organoids with SARS-CoV-2. Single-cell RNA sequencing indicated injury and dedifferentiation of infected cells with activation of profibrotic signaling pathways. Importantly, SARS-CoV-2 infection also led to increased collagen 1 protein expression in organoids. A SARS-CoV-2 protease inhibitor was able to ameliorate the infection of kidney cells by SARS-CoV-2. Our results suggest that SARS-CoV-2 can directly infect kidney cells and induce cell injury with subsequent fibrosis. These data could explain both acute kidney injury in COVID-19 patients and the development of chronic kidney disease in long COVID

Factors Associated with Revision Surgery after Internal Fixation of Hip Fractures

Background: Femoral neck fractures are associated with high rates of revision surgery after management with internal fixation. Using data from the Fixation using Alternative Implants for the Treatment of Hip fractures (FAITH) trial evaluating methods of internal fixation in patients with femoral neck fractures, we investigated associations between baseline and surgical factors and the need for revision surgery to promote healing, relieve pain, treat infection or improve function over 24 months postsurgery. Additionally, we investigated factors associated with (1) hardware removal and (2) implant exchange from cancellous screws (CS) or sliding hip screw (SHS) to total hip arthroplasty, hemiarthroplasty, or another internal fixation device. Methods: We identified 15 potential factors a priori that may be associated with revision surgery, 7 with hardware removal, and 14 with implant exchange. We used multivariable Cox proportional hazards analyses in our investigation. Results: Factors associated with increased risk of revision surgery included: female sex, [hazard ratio (HR) 1.79, 95% confidence interval (CI) 1.25-2.50; P = 0.001], higher body mass index (fo

Self-equalization of cell voltages to prolong the life of VRLA batteries in standby applications

10.1109/TIE.2009.2017094IEEE Transactions on Industrial Electronics5662115-2120ITIE

Optimized transformer design: inclusive of high-frequency effects

Switching circuits, operating at high frequencies, have led to considerable reductions in the size of magnetic components and power supplies, Nonsinusoidal voltage and current waveforms and high-frequency skin and proximity effects contribute to transformer losses. Traditionally, transformer design has been based on sinusoidal voltage and current waveforms operating at low frequencies. The physical and electrical properties of the transformer form the basis of a new design methodology while taking full account of the current and voltage waveforms and high-frequency effects. Core selection is based on the optimum throughput of energy with minimum losses. The optimum core is found directly from the transformer specifications: frequency, power output, and temperature rise. The design methodology is illustrated with a detailed design of a push-pull converter

An improved battery characterization method using a two-pulse load test

It is very important to have the ability to determine the available capacity, the state of charge (SoC), and the state of health (SoH) of a battery; this ensures that the battery has the available power for the system requirements. A battery is aged by charging and discharging cycles; this process degrades the chemical composition of the battery. An undercharged battery has sulphation and stratification effects that shorten the lifetime of the battery. Overcharging causes gassing and water loss. This paper describes a novel two-pulse test to determine the AHC, SoC, and SoH of a valve regulated lead acid (VRLA) and a lithium ion battery. These parameters are related to the voltage drop after each pulse of current discharge. The first pulse stabilizes the battery relative to its previous history, and the second pulse establishes the parameters. The new approach is fully validated by experiment