All articles starting with E
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Effective potential
The effective potential in general relativity is a function of the radial coordinate that reduces the Schwarzschild orbital motion of a test particle to a one-dimensional energy equation.
Effective radiated power
Effective radiated power (ERP) is a standardized measure of a transmitter's directional radio-frequency power: the antenna input power multiplied by the antenna's gain relative to a half-wave dipole.
Effective radiative forcing
Effective radiative forcing (ERF) is the change in Earth's energy balance from a climate perturbation after rapid atmospheric adjustments, measured in watts per square meter.
Effective radius (cloud physics)
The effective radius in cloud physics is a characteristic droplet radius, defined as the ratio of the third to the second moment of the particle size distribution.
Effective rainfall
Effective rainfall, also called effective precipitation, is the portion of total rainfall useful for a stated purpose, most often crop water supply in the root zone.
Effective sample size
Effective sample size (ESS) is a diagnostic for Markov chain Monte Carlo expressing how many independent draws would carry the same estimation information as autocorrelated draws obtained.
Effective SNR mapping
Effective SNR mapping (ESM) is a physical-layer abstraction in wireless communications that compresses per-subcarrier SINR values into one effective SNR, used in LTE, 5G NR, and WiMAX simulators.
Effective tax rate
The effective tax rate is the share of income actually paid in tax, typically a corporation's tax expense divided by pretax book income, and it often differs from the statutory rate.
Effective temperature
Effective temperature is the temperature at which a blackbody would radiate the same total power as a source; Earth's is 254.0 K against a surface mean of 15°C.
Effectiveness factor
The effectiveness factor is a dimensionless number in heterogeneous catalysis, the ratio of a porous pellet's actual reaction rate to the rate without internal diffusion limitation.
Effector protein Avr2-like
Avr2-like (A2l) is an allelic RXLR effector variant of Phytophthora infestans that evades recognition by the potato R2 immune receptor, unlike AVR2; distinct from the unrelated fungal Avr2 protease inhibitors of Cladosporium fulvum and Fusarium oxysporum.
Effector T cell
Effector T cell: antigen-activated T lymphocyte (Teff) that performs immediate immune action via cytotoxicity and cytokines, marked by T-bet, EOMES, BLIMP-1, high glycolysis, no self-renewal; distinct from central and effector memory subsets.
eFFECTOR Therapeutics
eFFECTOR Therapeutics was a clinical-stage biopharmaceutical company in Solana Beach, California, founded in 2012, whose cancer drugs tomivosertib and zotatifin failed to save it from winding down in 2024.
Effector TSP1
Effector TSP1 (Tsp1) is a small secreted cysteine-rich effector protein of the fungus Trichoderma virens, structurally a dimeric beta-barrel related to Alt a1 and PevD1, that induces salicylic acid mediated susceptibility in maize.
Effects and aftermath of rape
Effects and aftermath of rape: immediate medical care (STI prophylaxis, emergency contraception within 120 hours, hepatitis B and HPV vaccination), rape trauma syndrome and PTSD, long-term health effects, and secondary victimization in legal systems.
Effects of cannabis
Effects of cannabis (marijuana): THC and CBD act on the endocannabinoid system's CB1/CB2 receptors, causing euphoria, increased heart rate, memory impairment, addiction risk (3 in 10 users), and limited FDA-approved therapeutic uses like Epidiolex.
Effects of climate change
The effects of climate change are the consequences of human-caused global warming: rising temperatures, melting ice, sea level rise, and extreme weather that disrupt health, food systems, and economies.
Effects of climate change on small island countries
Climate change severely affects small island countries, which contribute little to global emissions but face sea-level rise, stronger cyclones, drought, and food and water insecurity.
Effects of divorce
Effects of divorce cover consequences of marital dissolution for adults and children. US research links parental divorce to lower adult earnings, higher incarceration, teen births, and mortality, mediated by income loss, neighborhood change, and reduced parent proximity.
Effects of domestic violence on children
Children's exposure to domestic violence, also called witnessing domestic violence, is when children see, hear, or are otherwise involved in home violence between adults, now recognized as a form of child abuse with psychological, behavioral, health, and intergenerational effects.
Effects of electric current
Effects of electric current, also indexed as electric shock and electrocution, is the ICD-11 medical category covering electrical injuries ranging from skin burns to fatal organ damage.
Effects of heat
Effects of heat (ICD-11 NF01): adverse effects from failure to maintain normal core temperature in excessive heat, spanning heat syncope, heat exhaustion, and heat stroke (core temperature ≥40°C with CNS dysfunction).
Effects of high altitude on humans
Effects of high altitude on humans: hypobaric hypoxia above ~2,500 m lowers oxygen partial pressure, driving acclimatization, altitude illness (AMS, HACE, HAPE), sleep disturbance, and performance limits near Everest's 8,848 m summit.
Effects of hunger
Effects of hunger (ICD-11 NF07.0): health consequences of lacking food, from metabolic shutdown, organ wasting, and infection risk to famine; 645 million people faced hunger in 2025.
Effects of Hurricane Beryl in Texas
Hurricane Beryl struck the Texas coast near Matagorda on July 8, 2024 as a Category 1 storm, killing at least 36 people and knocking out power to nearly 2.8 million customers.
Effects of Hurricane Helene in Georgia
Hurricane Helene struck Georgia on September 26 and 27, 2024, causing over 1.5 million power outages, about 34 deaths, and at least $5.5 billion in agricultural losses.
Effects of Hurricane Helene in North Carolina
Hurricane Helene struck western North Carolina on September 26–27, 2024, bringing record rainfall, catastrophic flooding, over 2,000 landslides, 107 deaths, and an estimated $59.6 billion in damage, the costliest storm in state history.
Effects of Hurricane Katrina in New Orleans
The effects of Hurricane Katrina in New Orleans, also called the Great Flood of New Orleans, began when levee failures on August 29, 2005 flooded 80 percent of the city, killing hundreds.
Effects of Hurricane Maria in Puerto Rico
Hurricane Maria struck Puerto Rico as a Category 4 storm on September 20, 2017, causing the longest blackout in U.S. history, an estimated 2,975 deaths, and a mass migration to the mainland.
Effects of Hurricane Sandy in New York
The effects of Hurricane Sandy in New York began on October 29, 2012, when a record storm tide flooded subways and homes, killing 43 people and causing $19 billion in damage.