Abstract: A device for monitoring the expiration of goods includes a substrate and an unreacted composition affixed thereto which is intrinsically reactive to one or both of its thermal environment and the length of time following activation. The reactivity results in a color formation of the composition with the color formation being a single color upon reaction to one of said thermal environment or length of time and multiple colors upon reaction to both. The device may be a label affixed to a container containing the goods to be monitored or may be printed directly on a container.

Abstract: A molecular sensor for detecting small concentrations of a target molecular even in the presence of other molecules having similar shape and chemistry. Two QCM sensors are provided, both of which are covered with polymeric coatings having essentially the same chemistry. One of the QCM sensors is molecularly imprinted while the other is not. The output of the two QCM signals is compared to indicate the presence of the target molecule.

Abstract: A motor vehicle wiper includes a wiper blade mounted on the free end of a wiper arm and pressing a wiping stem against the glass to be wiped. The wiper is provided with a wear indicator using a substance based at least on an azo compound.

Abstract: Embodiments of the present invention are directed to providing a leakage detecting method for use in an oxidizing system of forming an oxide layer so as to shorten leakage detecting time period. In one embodiment, a leakage detecting method for use in an oxidizing system of forming an oxide layer comprises performing oxidizing processes on a plurality of test wafers in a plurality of test runs under a specified operating condition in an oxidizing system having an oxidizing chamber to form oxide layers on the test wafers having a plurality of oxide thicknesses for the plurality of test runs by flowing an oxidizing gas through the oxidizing chamber containing the test wafers. An oxygen concentration of the oxidizing gas exiting the oxidizing chamber is measured in each of the plurality of test runs.

Abstract: The present invention relates to a method for the analysis of a gaseous component or of a component that can be transformed into gaseous form (23) of a sample (5) which provides that the sample (5) is filled into a sample receptacle (2) through a receptacle opening (4), and an analysis receptacle (7), which was previously supplied with a tracer reagent, is then by way of its receptacle opening (4) connected with the receptacle opening (4) of sample receptacle (2) via an adapter (10), after which step the component (23) is expelled from the sample receptacle (2) and into the analysis receptacle (7) wherein the analysis receptacle (7) is connected with the outside atmosphere in such a manner that a pressure compensation can take place. The invention further relates to a test kit, in particular, a test kit for implementing the method.

Abstract: A comparator for use with a time-temperature indicator wherein the time-temperature indicator includes an active portion having an initial color and which undergoes chemical changes as time elapses and at a rate related to the temperature of the surrounding environment and wherein the chemical changes produce changes in the color of the active portion. The comparator comprises a substantially planar support member, and a plurality of comparator stages located on the support member. Each comparator stage comprises a first portion having a reference color and a second portion having a predetermined color that is the same as one of the colors to which the active portion of the time-temperature indicator changes.

Abstract: The present invention relates to bacterial luciferase expression cassettes suitable for conferring bioluminescence properties on Gram-positive bacteria, cells transformed with such cassettes, and methods of making and using such cassettes.

Abstract: Non-destructive systems and methods for temperature measurements are described so that the remaining operational life and accumulated damage of high temperature gas turbine components can be assessed. Alloy-based witness coupons and diffusion couple witness coupons are attached to, or directly applied onto, high temperature components so that they experience the same high temperature operation and shut down as the components themselves. The witness coupons are later removed from the components and analyzed, or are analyzed on the component, to determine the change to their microstructure, metallurgy, and/or diffusion characteristics. Since the time each component spends in operation is known, the operating temperatures of the components can be back-calculated from the microstructural, metallurgical, and/or diffusion characteristic changes of the witness coupons. Therefrom, the remaining operational life of the component can be assessed, as can the accumulated damage to the component.

Abstract: The present invention provides an object, which, in its outer surface contains a color-forming composition which comprises a solvent-absorbing material that is generally a polymer; a color-former compounded with the solvent-absorbing material, where the color-former functions as a metal chelating agent; and metal ions capable of forming a chelate complex with the color-former as the solvent-absorbing material absorbs a solvent, resulting in a detectable color change of the composition. The present invention also provides a method for indicating exposure of the color-forming composition to a solvent, wherein the color-forming composition is to be used on the outside surface of objects.

Abstract: The invention provides method for the evaluation of washing or cleaning techniques on a substrate comprising:

Abstract: The present invention relates to a method for the selected chemical activation of photo-activatable cross-linker molecules around ligand binding pockets and fluorescent groups in macromolecules, especially biological macromolecules, by using fluorescent ligands of the macromolecule and by selecting photo-activatable cross-linker molecules having specific activation energies so that a radiationless energy transfer (Förster transfer) from the fluorescent ligands to the cross-linker molecules, which become activated thereby, takes place.

Abstract: Devices and methods are disclosed that are effective to produce reliable vapor measurements in the presence of drift. In certain instances the sensor module is mounted externally on a housing. In other instances, the sensor module contains a first sensor element incorporating a first array of sensors and a second sensor element incorporating a second array of sensors wherein both sensor elements are mounted externally on the housing. In other embodiments, the present invention relates to mapping an x-y surface for detection of an analyte, the method includes moving in tandem at least two sensor arrays separated by a distance “d” across an x-y surface to produce a plurality of responses and analyzing the responses to map the x-y surface for detection of an analyte. Moreover, the present invention provides a sensor module, such as in a handheld device, comprising at least two pneumatic vapor paths and at least two sensor arrays.

Abstract: Methods, systems, kits for carrying out a wide variety of different assays that comprise providing a first reagent mixture which comprises a first reagent having a fluorescent label. A second reagent is introduced into the first reagent mixture to produce a second reagent mixture, where the second reagent reacts with the first reagent to produce a fluorescently labeled product having a substantially different charge than the first reagent. A polyion is introduced into at least one of the first and second reagent mixtures, and the fluorescent polarization in the second reagent mixture relative to the first reagent mixture is determined, this fluorescent polarization being indicative of the rate or extent of the reaction.

Abstract: The invention provides a cDNA which encodes tapasin-like protein. It also provides for the use of the cDNA, protein, and antibody in the diagnosis, prognosis, treatment and evaluation of therapies for cancer. The invention further provides vectors and host cells for the production of the protein and transgenic model systems.

Abstract: A method for the production of a holographic sensor wherein the holographic recording material forming the sensitive element is a polymer matrix, which comprises diffusing into the matrix one or more soluble salts that undergo reaction in situ to form an insoluble sensitive precipitate; and recording a holographic image. This method allows the production of a holographic sensor wherein the holographic recording material forming the sensitive element is an insoluble polymer film.

Abstract: A method of authenticating products or packaging by analyzing key ingredients on products or on product packaging is disclosed. Light-sensitive compounds can be used to identify the product or product packaging. The product or product package may include visible or invisible ink containing a particular light-sensitive compound. One or more light-sensitive compounds and ink, if used, may be printed in one or more locations on the product or product packaging to produce an authentication mark to inhibit inadvertent or intentional removal of the mark, thereby rendering the mark tamper-resistant. The mark is sealed to isolate the mark from the environment. A device may be used to irradiate the mark and read light absorption or emission. A controller determines the authenticity of the mark by comparing the emitted or absorbed properties to a standard.

Abstract: A sensor device is disclosed, as well as methods and systems for determining a barrier property of each coating of an array of barrier coatings deposited onto a fluid-permeable or fluid-impermeable substrate. The systems and methods include the sensor device having a sensing layer responsive to a fluid of interest for which the barrier property of the array of coatings are desired to be determined. The sensor device further includes an overlayer disposed between the array of barrier coatings and the sensing layer. The overlayer protects the sensing layer from being damaged by the coatings.

Abstract: A weathering test method comprising making active oxygen and light simultaneously act on a test piece, a weathering test method comprising successive and/or alternate steps of making active oxygen and light simultaneously act on a test piece and making at least one of light, oxygen, and water to act on the test piece, and apparatus for carrying out the methods are disclosed. In evaluating weatherability of organic materials, articles made of organic materials or articles coated with organic materials, the methods and apparatus achieve acceleration of deterioration of test pieces to greatly reduce the testing time.

Abstract: The invention relates to a method for detecting a double-stranded region in a nucleic acid by (1) providing two separate, adjacent pools of a medium and a interface between the two pools, the interface having a channel so dimensioned as to allow sequential monomer-by-monomer passage of a single-stranded nucleic acid, but not of a double-stranded nucleic acid, from one pool to the other pool; (2) placing a nucleic acid polymer in one of the two pools; and (3) taking measurements as each of the nucleotide monomers of the single-stranded nucleic acid polymer passes through the channel so as to differentiate between nucleotide monomers that are hybridized to another nucleotide monomer before entering the channel and nucleotide monomers that are not hybridized to another nucleotide monomer before entering the channel.

Abstract: Systems and methods for analyzing a viscoelastic property of a combinatorial library of materials including a plurality of full bridge devices operable for measuring a temperature-modulated elongation property of each of a plurality of combinatorial materials, wherein each of the plurality of full bridge devices comprises a plurality of strain gauges operable for measuring a temperature-modulated elongation property of each of the plurality of combinatorial materials, and wherein each of the plurality of combinatorial materials is disposed on a surface of the plurality of full bridge devices. The systems and methods also including an algorithm disposed within a computer, the algorithm operable for equating the temperature-modulated elongation property of the combinatorial materials with a thermal property of the combinatorial materials.

Abstract: The use of semiconductor nanocrystals as detectable labels in various chemical and biological applications is disclosed. The methods find use for detecting a single analyte, as well as multiple analytes by using more than one semiconductor nanocrystal as a detectable label, each of which emits at a distinct wavelength.

Abstract: A sterilant challenge device (1), for use in testing the efficiency of the air removal stage of a sterilization cycle in a sterilizer, includes a tube (2) of thermally-insulating material, the bore of which is closed at one end (3) and open at the other for the entry of sterilant. A plurality of thermally-conductive masses (4) is located around the tube (2) and thermally-separated from one another by air gaps (14), and a temperature sensor is located in an opening (16) in one of the masses adjacent the closed end of the tube. An outer casing (5) defines an air space around the thermally-conductive masses and thermally insulates the masses from the heat in the sterilizer.

Abstract: The present invention relates to new color compositions which are especially suitable to be used in oxygen indicators. The compositions comprise iron(II), an agent containing pyrogallol entities and an organic acid.

Abstract: The present invention provides an evaluation method and an evaluation system of free halogen concentration which eliminate the necessity of early exchanging or recycling of catalysts, as compared with a conventional method or system. In the present evaluation method of free halogen concentration, a main flow path of a sample liquid for evaluation and a sub-region that communicates with the main flow path are formed, a potential-measuring electrode is installed in the main path, while a reference electrode is installed in the sub-region at a position where free halogen in the sample liquid has been decomposed. Moreover, free halogen in the sample liquid is decomposed by a free-halogen decomposing substance in the sub-region, and the free halogen concentration is evaluated from the electric potential difference between the reference electrode and the potential-measuring electrode.

Abstract: Methods for determining the presence of double stranded nucleic acids in a sample are provided. In the subject methods, nucleic acids present in a fluid sample are translocated through a nanopore, e.g. by application of an electric field to the fluid sample. The current amplitude through the nanopore is monitored during the translocation process and changes in the amplitude are related to the passage of single- or double-stranded molecules through the nanopore. The subject methods find use in a variety of applications in which the detection of the presence of double-stranded nucleic acids in a sample is desired, e.g. in hybridization assays, such as Northern blot assays, Southern blot assays, array based hybridization assays, etc.

Abstract: A solid state device is formed through thin film deposition techniques which results in a self-supporting thin film layer that can have a precisely defined channel bored therethrough. The device is useful in the chacterization of polymer molecules by measuring changes in various electrical characteristics as molecules pass through the channel. To form the device, a thin film layer having various patterns of electrically conductive leads are formed on a silicon substrate. Using standard lithography techniques, a relatively large or micro-scale aperture is bored through the silicon substrate which in turn exposes a portion of the thin film layer. This process does not affect the thin film. Subsequently, a high precision material removal process is used (such as a focused ion beam) to bore a precise nano-scale aperture through the thin film layer that coincides with the removed section of the silicon substrate.

Abstract: The antioxidant power of an organic or inorganic liquid is determined by causing it to enter into competition with bathocuproine (BC) in a copper sulphate solution. Bathocuproine (BC) forms stable complexes with the monovalent Cu. Such a reaction is specific for Cu(I) and not for divalent Cu(II). Cu(II) in solution can be reduced to Cu(I) by a number of reducing compositions belonging to a class of compositions consisting prevailingly of both liposoluble and water soluble non-enzymatic antioxidants. When the reaction occurs in a bathocuproine (BC) buffer, the complex being formed is characterized by the concentration of the reducing agents and then, by good approximation, of the antioxidants present in the system. The quantitative analysis of such a reaction can be easily made by spectrophotometry at 480 nm both by macro- and micromethods with the use of a number of reducing standard compositions with known concentrations.

Abstract: A fluorescent probe is applied to bind to a metal oxide on a substrate and the substrate is exposed to an ultraviolet light to identify the metal oxide. A chemical cleaning or stripping solution is selected by combinatorial high throughput screening (CHTS). In the method, an array of regions is defined on a substrate, a candidate cleaning/stripping solution is deposited onto the regions to effect cleaning/stripping of the regions; a fluorescent probe is applied to bind to a metal oxide on the substrate; the substrate is exposed to an ultraviolet light to identify the metal oxide and a product of the cleaning/stripping is evaluated according to the identified metal oxide. An activated metal substrate composition is provided that comprises a metal substrate with a contaminant metal oxide coating and a fluorescent activator bound to the substrate by reaction with the metal oxide coating.

Abstract: Workstation, apparatuses and methods for the high-throughput synthesis, screening and/or characterization of combinatorial libraries. The invention relates to an array, which permits various high-throughput methods for synthesis, screening and/or characterization in the same array, without requiring sample transfer from the array. In a preferred embodiment, the synthesis, screening, and/or characterization steps are carried out in a highly parallel fashion, where more than one compound is synthesized, screened, and/or characterized at the same time. The invention may be practiced at the microscale. The array may comprise thermal channels, for regulating the temperature of the wells in the array. The wells of the array may comprise a membrane, which is used in various screening and characterization methods. The invention also relates to a covered array, comprising the array and an array cover, as well as an apparatus comprising the array, which comprises the array, an array cover and a stage.

Abstract: The present invention provides methods of identifying hot-spot residues for one or both members of a receptor-ligand complex of interest. Further provided are methods of using receptor hot-spot residues to identify compounds that functionally bind a receptor in a manner that mimics the binding of a known ligand for the receptor.

Abstract: A weathering test method comprising making active oxygen and light simultaneously act on a test piece, a weathering test method comprising successive and/or alternate steps of making active oxygen and light simultaneously act on a test piece and making at least one of light, oxygen, and water to act on the test piece, and apparatus for carrying out the methods are disclosed. In evaluating weatherability of organic materials, articles made of organic materials or articles coated with organic materials, the methods and apparatus achieve acceleration of deterioration of test pieces to greatly reduce the testing time.

Abstract: A detector for monitoring an analyte includes an analyte-sensing composition. The analyte-sensing composition has a visible color intensity or emission intensity (e.g., fluorescence intensity) that changes as the analyte concentration contacting the detector changes. The intensity changes can be visible to the human eye, or identified by an instrument. The analyte can include carbon dioxide, a volatile amine or a volatile carboxylic acid.

Abstract: A polymeric food spoilage sensor comprises a polymer containing a polyazamacrocyclic transition metal complex. The complex selectively binds biogenic amines, such as cadaverine, putrescine and histamine, which are released by food spoilage microorganisms. The polymer undergoes a detectable color change upon exposure to biogenic amine, thus indicating that food spoilage has probably occurred. In one embodiment, the polymer is molecularly imprinted with the biogenic amine to impart selective binding affinity. The polymer is easily incorporated in common food containers and can be employed in fiber optic detection devices.

Abstract: An insulating glass pane (1) has at least two glass plates (10, 12) which are spaced apart from one another, and an edge joining strip (14) which surrounds and joins together the glass plates (10, 12) in the region of their edges. The edge joining strip (14) seals and delimits an insulating cavity (16) which is located between the glass plates (10, 12) and which is filled with a fill gas which is not air. A sensor (18) is provided in the insulating cavity (16) of the insulating glass pane (1), which sensor reacts and gives a signal if the composition of the fill gas changes.

Abstract: Described herein are assays and components for encoding and decoding microspheres. Each assay or component described utilizes at least one nanocrystal.

Abstract: An irreversible temperature indicating paint comprises 29 wt % to 37 wt % cobalt chromite spinel, alumina, gold purple and frit, 35 wt % to 45 wt % acrylic resin and 20 wt % to 30 wt % silicone resin excluding solvent. The solvent comprises a mixture of 80% 1-methoxy-2-propanol and 20% dipropylene glycol monomethyl ether. A particular irreversible temperature indicating paint comprises 34.9 wt % cobalt chromite spinel, alumina, gold purple and frit, 42.5 wt % acrylic resin and 22.6 wt % silicone resin excluding solvent. The irreversible temperature indicating paint has four or more colour changes in the temperature range 500° C. to 900° C. The irreversible temperature indicating paint is used to determine the temperatures to which various parts of turbine blades, turbine vanes or other component are subjected in operation of a gas turbine engine.

Abstract: An irreversible temperature indicating paint comprise 15 to 18 wt % cobalt ammonium phosphate, 5.0 to 6.0 wt % sodium alumino sulpho silicate, 8.5 to 10.5 wt % silica, 7.0 to 8.5 wt % alumina, 0.5 to 0.7 wt % toluidine red, 35 to 43 wt % acrylic resin and 19 to 23 wt % silicone resin excluding solvent. A particular irreversible temperature indicating paint comprising 16.4 wt % cobalt ammonium phosphate, 5.5 wt % sodium alumino sulpho silicate, 9.4 wt % silica, 7.8 wt % alumina, 0.6 wt % toluidine red, 39.1 wt % acrylic resin and 21.1 wt % silicone resin excluding solvent. The irreversible temperature indicating paint has at least six colour changes in the temperature range 550° C. to 1250° C. The irreversible temperature indicating paint is used to determine the temperatures to which various parts of turbine blades, turbine vanes or other components are subjected in operation of a gas turbine engine.

Abstract: An irreversible temperature indicating paint comprises 29 wt % to 37 wt % cobalt zinc silicon blue phenacite and a frit, 35 wt % to 45 wt % acrylic resin and 20 wt % to 30 wt % silicone resin excluding solvent. The solvent comprises a mixture of 80% 1-methoxy-2-propanol and 20% dipropylene glycol monomethyl ether. A particular irreversible temperature indicating paint comprises 34.9 wt % cobalt zinc silicon blue phenacite and a frit, 42.5 wt % acrylic resin and 22.6 wt % silicone resin excluding solvent. The irreversible temperature indicating paint is used to determine the temperatures to which various parts of turbine blades, turbine vanes or other components are subjected in operation of a gas turbine engine.

Abstract: Immunoassay methods for measuring the concentration of an analyte in a test specimen are described. The methods use an immunoreagent, where one of the analyte and the immunoreagent is an antigen, and the other of the analyte and the immunoreagent is an antibody which specifically binds to the antigen. An important feature distinguishing these immunoassays over conventional immunoassays is that the standard sample containing a known concentration of analyte is measured in the same reaction vessel as the test specimen containing an unknown amount of analyte.

Abstract: A method for observing and determining the size of individual molecules and for determining the weight distribution of a sample containing molecules of varying size, which involves placing a deformable or nondeformable molecule in a medium, subjecting the molecule to an external force, thereby causing conformational and/or positional changes, and then measuring these changes. Preferred ways to measure conformational and positional changes include: (1) determining the rate at which a deformable molecule returns to a relaxed state after termination of the external force, (2) determining the rate at which a molecule becomes oriented in a new direction when the direction of the perturbing force is changed, (3) determining the rate at which a molecule rotates, (4) measuring the length of a molecule, particularly when it is at least partially stretched, or (5) measuring at least one diameter of a spherical or ellipsoidal molecule.

Abstract: A sensor device is disclosed, as well as methods and systems for determining a barrier property of each coating of an array of barrier coatings deposited onto a fluid-permeable or fluid-impermeable substrate. The systems and methods include the sensor device having a sensing layer responsive to a fluid of interest for which the barrier property of the array of coatings are desired to be determined. The sensor device further includes an overlayer disposed between the array of barrier coatings and the sensing layer. The overlayer protects the sensing layer from being damaged by the coatings.

Abstract: A method of obtaining physical and/or chemical characteristics of a biological medium, comprising submitting said medium to at least two currents Ii of different strength and frequency fi, by means of a first group of electrodes, measuring the voltage drop Ui in said medium by means of a second group of electrodes, positioning a first element of the first group of electrodes and a second element of the second group of electrodes in a first zone of said medium, and positioning a third element of the first group of electrodes and a fourth element of the second group of electrodes in a second zone of said medium.

Abstract: In the present invention, a temperature indicating material is prepared by incorporating, in a rewritable base system which comprises an electron donating compound, an electron accepting compound and a reversal material and undergoes color changes with temperature and time, a thermochromism controller which changes a rate of crystal to amorphous or phase-separation to non-phase-separation rate. Upon color changes with an environmental temperature, the thermochromism controller undergoes crystallization or phase separation to have a function as a place for reaction and contributes to the color changes of the temperature indicating material. The incorporation of the thermochromism controller therefore makes it possible to impart the resulting temperature indicating material with improved sensitivity to temperature at around an environmental temperature and a high S/N ratio.

Abstract: A device composed of (1) a color changing indicator, (2) an optional polymeric binder, preferably having gel forming capability, and (3) an activator solvent system which induces a color change in the indicator when device is frozen, in the region of about 0 to −30° C. An example of the device is an indicator of a fine dispersion of partially polymerized diacetylene of the formula: R—C═C—C═C—R, where R is a substituent group, e.g., 4BCMU where R=—(CH2)OCONHCH2COO(CH2)4H, dispersed in a mixture of solvents, e.g., 96:4 water:ED (ethylene glycol diacetate), with or without a polymeric binder. When the temperature of the device is lowered to the freezing point of water, the activator solvent phase separates out of the mixture and induces a color change in the indicator. The device can undergo an irreversible color change, e.g., from blue to red, when the activator mixture is frozen in the region of about 0 to 30° C.

Abstract: A system to detect spoilage of a food product is described in this invention. The present invention can be used to see if a food product is spoiled, by mixing a part of the food product with an indicator of food spoilage within a separate transparent compartment of the food container, which is visible to the consumer.

Abstract: The invention lies in a method and an apparatus for controlling the regeneration of an NOx, storage converter disposed in the exhaust-gas system of an internal-combustion engine and can be operated in an absorption mode and a regeneration mode, with operating parameters of the internal-combustion engine being changed as a function of the operating state of the NOx storage converter. The NOx concentration in the exhaust gas is measured downstream of the NOx storage converter. For determining the operating state, particularly damage to the NOx storage converter, when the NOx storage converter switches from the absorption mode to the regeneration mode, the values of characteristic features of an NOx desorption peak in the time curve of the NOx concentration are ascertained and compared to predetermined test patterns, with a comparison result being formed, from which a converter-state signal that characterizes the operating state of the NOx converter is determined.

Abstract: A solubility reporter for measuring a protein's solubility in vivo or in vitro is described. The reporter, which can be used in a single living cell, gives a specific signal suitable for determining whether the cell bears a soluble version of the protein of interest. A pool of random mutants of an arbitrary protein, generated using error-prone in vitro recombination, may also be screened for more soluble versions using the reporter, and these versions may be recombined to yield variants having further-enhanced solubility. The method of the present invention includes “irrational” (random mutagenesis) methods, which do not require a priori knowledge of the three-dimensional structure of the protein of interest. Multiple sequences of mutation/genetic recombination and selection for improved solubility are demonstrated to yield versions of the protein which display enhanced solubility.

Abstract: A liquid chemical stripping or cleaning solution is selected by combinatorial high throughput screening. A high throughput screening well array assembly includes (A) a metal substrate and (B) a mask that defines an array of wells on the substrate. A combinatorial high throughput screening system includes (A) a metal substrate and (B) a mask that defines an array of wells on the substrate and a reaction vessel to receive the well array assembly.

Abstract: Methods for determining the presence of double stranded nucleic acids in a sample are provided. In the subject methods, nucleic acids present in a fluid sample are translocated through a nanopore, e.g. by application of an electric field to the fluid sample. The current amplitude through the nanopore is monitored during the translocation process and changes in the amplitude are related to the passage of single- or double-stranded molecules through the nanopore. The subject methods find use in a variety of applications in which the detection of the presence of double-stranded nucleic acids in a sample is desired, e.g. in hybridization assays, such as Northern blot assays, Southern blot assays, array based hybridization assays, etc.

Abstract: A method of screening a subject for risk of developing Alzheimer's disease comprises determining the presence of at least one ApoE4 allele in a subject, and determining the presence or absence of decreased estrogen levels in said subject (e.g., due to previous or impending menopause or hysterectomy). The presence of at least one ApoE4 allele (and particularly two ApoE4 alleles) in combination with decreased estrogen levels in said subject indicating said subject is at greater risk of developing Alzheimer's disease (e.g., as compared to subjects with at corresponding number of ApoE4 alleles, but who do not have decreased estrogen levels), and that the subject will receive greater benefit from estrogen replacement therapy in treating Alzheimer's disease than a subject who does not carry one or two ApoE4 alleles.