NCEPNational Centers for Environmental Prediction. A part of the National Weather Service which provides nationwide computerized and manual guidance to…
Neap TideA minimum tide occurring at the first and third quarters of the moon.
Near Real TimeWhen referred to in textual references, the ARM conception of "near-real time" is "with a few hours delay."
near-surface soil heat fluxA quantity measured near the surface of the soil, according to the formula B = λ(dT/dz), where λ is the conductivity of the soil that the heat or…
near-surface soil moisture fluxA quantity measured near the surface of the soil, according to the formula B = λ(dq/dz), where λ is the conductivity of the soil that the heat or…
Nearshore Forecast(NSH) - National Weather Service seasonal marine forecasts for an areas of the Great Lakes extending from a line approximating mean low water datum along…
Neat fuelFuel that is free from admixture or dilution with other fuels.
Neatlines (of structure)A line which defines the limits of work, such as an excavation, cut stone, etc.
negative autogenous regulationInhibition of the expression of a gene or set of co-ordinately regulated genes by the product of the gene or the product of one of the genes.
negative control systemA mechanism by which a regulatory protein is required to turn off gene expression.
Negative Energy BalanceWhen producing a fuel takes more energy than the amount of energy the fuel provides.
negative feedbackthe process by which an initial change brings about an additional change in the opposite direction.
Negative pressurePressure within a pipe that is less than atmospheric pressure.
negative selectionSelection against individuals possessing a certain character. Opposite: positive selection.
Neo-Traditional DevelopmentA traditional neighborhood, where a mix of different types of residential and commercial developments form a tightly knit unit.
neomycin phosphotransferase II(Abbreviation: npt-II). An enzyme which detoxifies the antibiotic neomycin, used as a marker gene to select for successfully transformed cells in plant…
neoplasm(NEE-oh-PLA-zum) An abnormal mass of tissue that results when cells divide more than they should or do not die when they should.
NeopreneA synthetic rubber with superior resistance to oils; often used as gasket and washer material.
NESDISNational Environmental Satellite, Data, and Information Service. NESDIS collects, processes, stores, analyzes, and disseminates various types of…
NestinAn intermediate filament protein found in cells such as neural and pancreatic precursors.
Net (Lower) Heating Value (NHV)The potential energy available in a fuel as received, taking into account the energy loss in evaporating and superheating the water in the fuel.
Net All-Wave RadiationThe net or resultant value of the upward and downward longwave and shortwave radiative fluxes through a plane at the earth-atmosphere interface; a…
Net billingThe arrangement by which the Bonneville Power Administration financed the cost of nuclear power plants.
Net capabilityThe maximum load-carrying ability of the equipment, exclusive of station use, under specified conditions for a given time interval, independent of the…
Net cutThe cut required, less the fill required, at a particular station or part of a road.
Net emissionsApplied to greenhouse gas emissions inventory in this report. "Net emissions" means gross emissions (including all industrial activities, mostly fossil…
Net Energy Production (or Balance)The amount of useful energy produced by a system less the amount of energy required to produce the fuel.
Net fillThe fill required, less the cut required, at a particular station or part of a road.
Net GenerationEqual to gross generation less electricity consumption of a power plant.
Net heating value (NHV)The potential energy available in the fuel as received, taking into account the energy loss in evaporating and superheating the water in the sample.
Net MeteringThe practice of using a single meter to measure consumption and generation of electricity by a small generation facility (such as a house with a wind or…
net photosynthesisPhotosynthetic activity minus respiratory activity, measured by the net absorption of carbon dioxide.
Net Present ValueThe value of a personal portfolio, product, or investment after depreciation and interest on debt capital are subtracted from operating income.
net radiationThe difference between upwelling and downwelling, covering longwave and shortwave radiation.
Net RainfallThe portion of rainfall which reaches a stream channel or the concentration point as direct surface flow.
Net terrestrial radiationNet terrestrial radiation Difference between the downward and upward terrestrial radiation fluxes; net flux of terrestrial radiation.
Network of MPAsA set of discrete MPAs within a region or ecosystem that are connected through complementary purposes and synergistic protections.
Neural crestA band of cells that extend lengthwise along the neural tube of an embryo and give rise to cells that form the cranial, spinal, and autonomic ganglia, as…
Neural plateA thickened band of ectoderm along the dorsal surface of an embryo. The nervous system develops from this tissue.
Neural stem cellA type of stem cell that resides in the brain, which can make new nerve cells (called neurons) and other cells that support nerve cells (called glia).
Neural stem cell (NSC)A stem cell found in adult neural tissue that can give rise to neurons, astrocytes, and oligodendrocytes.
Neural tubeThe embryological forerunner of the central nervous system.
NeuroectodermThe central region of the early embryonic ectoderm, which later forms the brain and spinal cord, as well as evolving into nerve cells of the peripheral…
NeuroepitheliumA specialized epithelial structure that forms the termination of a nerve of a special sense, i.e.
neurofibromatosisAn inherited progressive disorder in which tumors form on peripheral nerves. The tumors can be severely disfiguring and can also result in loss of hearing…
NeuronsNerve cells, the structural and functional unit of the nervous system. A neuron consists of a cell body and its processes-an axon and one or more…
NeurosphereA primitive neural tissue that arises when embryonic stem cells are grown in certain culture conditions.
neutral detergent fiberOrganic matter that is not solubilized after one hour of refluxing in a neutral detergent consisting of sodium lauryl sulfate and EDTA at pH 7.
Neutral LineThe line that separates longitudinal magnetic fields of opposite polarity.
neutral mutationA mutation that changes the nucleotide sequence of a gene, but has no observable effect on the fitness of the organism.
Neutral StabilityAn atmospheric condition that exists in unsaturated air when the environmental lapse rate equals the dry adiabatic rate, or in saturated air when the…
neutral theoryThe theory that much of evolution has been primarily due to random drift of neutral mutations.
NeutrinoA lepton with no electric charge. Neutrinos participate only in weak and gravitational interactions and are therefore very difficult to detect.
NeutronA baryon with electric charge zero; it has the basic structure of two down quarks and one up quark (held together by gluons).
Neutron probeAn instrument used to estimate soil moisture. Relates the rate of attenuation in pulsed neutron emissions to soil water content.
neutropenia(noo-troh-PEE-nee-uh) An abnormal decrease in the number of neutrophils, a type of white blood cell.
neutrophil(NOO-tro-fil) A type of white blood cell.
New UrbanismNeighborhood design trend used to promote community and livability. Characteristics include narrow streets, wide sidewalks, porches, and homes located…
New York Mercantile Exchange (Nymex)The centralized exchange where CFTC–sanctioned natural gas and electricity futures are traded in the United States.
New York rodA leveling rod marked with narrow lines, ruler-fashion.
NHCNational Hurricane Center - one of three branches of the Tropical Prediction Center (TPC).
NHOP(National Hurricane Operations Plan) - The NHOP is issued annually by the Federal Coordinator for Meteorological Services and Supporting Research.
nickTo break (or a break in) a phosphodiester bond in one of the strands of a double-stranded DNA molecule.
Nick translationA procedure for making a DNA probe in which a DNA fragment is treated with DNase to produce single-stranded nicks, followed by incorporation of…
nicked circleDuring the extraction of plasmid DNA from a bacterial cell, one strand of the DNA often becomes nicked.