155,060 Works

Physical Activity, Diet, and Risk of Alzheimer Disease

Nikolaos Scarmeas, Jose A. Luchsinger, Nicole Schupf, Adam M. Brickman, Stephanie Cosentino, Mingxin Tang & Yaakov Stern
CONTEXT: Both higher adherence to a Mediterranean-type diet and more physical activity have been independently associated with lower Alzheimer disease (AD) risk but their combined association has not been investigated. OBJECTIVE: To investigate the combined association of diet and physical activity with AD risk. DESIGN, SETTING, AND PATIENTS: Prospective cohort study of 2 cohorts comprising 1880 community-dwelling elders without dementia living in New York, New York, with both diet and physical activity information available. Standardized...

Texas Architecture: A Vistual History

Beth Dodd

Examining the Multifactorial Nature of Cognitive Aging with Covariance Analysis of Positron Emission Tomography Data

Karen L. Siedlecki, Christian G. Habeck, Adam M. Brickman, Yunglin Gazes & Yaakov Stern
Research has indicated that there may be age-related and Alzheimer's disease (AD) -related reductions in regional cerebral blood flow (rCBF) in the brain. This study explored differences in age- and AD-related rCBF patterns in the context of cognitive aging using a multivariate approach to the analysis of H215O PET data. First, an rCBF covariance pattern that distinguishes between a group of younger and older adults was identified. Individual subject's expression of the identified age-related pattern...

Pengaruh Penggunaan Media Penyerap Gas Buang Pada Alat Pengendali Pencemaran Udara Untuk Kendaraan Bermesin Diesel

Purwo Subekti
EFFECT OF USE OF GAS EYE INFLAMATION MADE IN AIR DISTROL POLLING CONTROL FOR DIESEL ENGINE VEHICLES Air pollution that was caused by motorized vehicle, which came from the emission of the vehicle, has produced bad impact on human health. This study has objectives to study the effect of the application of air pollution control device, whice was equipped with fiber optic, glass wool and active carbon, to emission of diesel motor vehicles. That control...

Pengaruh Penggunaan Media Penyerap Gas Buang Pada Alat Pengendali Pencemaran Udara Untuk Kendaraan Bermesin Diesel

Purwo Subekti
EFFECT OF USE OF GAS EYE INFLAMATION MADE IN AIR DISTROL POLLING CONTROL FOR DIESEL ENGINE VEHICLES Air pollution that was caused by motorized vehicle, which came from the emission of the vehicle, has produced bad impact on human health. This study has objectives to study the effect of the application of air pollution control device, whice was equipped with fiber optic, glass wool and active carbon, to emission of diesel motor vehicles. That control...

Charge-spin excitations of the Ising-type fractional quantum Hall ferromagnets

Karel Výborný, Annelene F. Dethlefsen, Rolf J. Haug & Arkadiusz Wójs
We study the low-lying excitations from the fractional quantum Hall states at filling factors 2/3 and 2/5 and argue that the charge-carrying excitations involve spin flips, and, in particular, possibly more than one. Energies obtained by exact diagonalization and transport activation gaps measured over a wide range of magnetic fields are invoked. We discuss the relevance of the noninteracting composite-fermion picture where both fractions correspond to the same filling factor 2 of the composite fermions....

Piezoelectric screening in single InAs/AlAs quantum dots

D. Sarkar, H.P. Van Der Meulen, J.M. Calleja, J.M. Meyer, Rolf J. Haug & Klaus Pierz
Micro-photoluminescence spectroscopy for varying temperature, excitation intensity and energy was performed on a single InAs/AlAs self-assembled quantum dot. A broad sideband at 1.2 meV of the zero phonon line is attributed to the exciton-acoustic phonon interaction via deformation potential coupling. The piezoelectric coupling of the exciton to long-wavelength phonons is also observed and gives rise to a narrow low-energy sideband at about 0.25 meV of the zero-phonon line. This band strengthens with decreasing density of...

Universal oscillations of high-order cumulants

Christian Flindt, Christian Fricke, Frank Hohls, Tomas Novotny, Karel Netocny, Tobias Brandes & Rolf J. Haug
We discuss our recent measurement of high-order cumidants of charge transport through a quantum dot. The cumulants were found to oscillate as functions of measurement time before reaching their linear-in-time asymptotics. A theoretical analysis revealed that such oscillations in fact constitute a universal phenomenon: for a large class of stochastic processes the high-order cumulants are predicted to oscillate as functions of basically any parameter. Here, we give an overview of these recent results, provide an...

Noise characterization of a single parameter quantized charge pump

Frank Hohls, Niels Maire, B. Kaestner, Klaus Pierz, Hans W. Schumacher & Rolf J. Haug
The shot noise of a single parameter quantized charge pump is studied. The pumped current can be varied using a control gate. Quantized current plateaus / = nefp with fp the pumping frequency and e the electron charge are observed. The shot noise is minimal for each current plateau and maximal in between. Interestingly the first expected quantized current plateau at n = 1 is missing for certain control gate voltages. We use the measured...

Economic evolution from a system theory perspective

Peter Rassidakis
Marburg economist Peter Rassidakis’ dissertation illustrates by means of system-theoretical tools how evolution as a process of increasing diversity takes place in different systems. Individual evolution processes are considered following a presentation of basic system-theoretical proposals: From a system theory perspective individuals are operatively closed systems which can increase their diversity through autopoietic reproduction of consciousness. Environmental stimuli lead to an awareness of unconscious incompetence and trigger learning processes which take place at several learning...

Computational physics from simple to complex systems

Edgar Martin
Diese Arbeit befasst sich mit Computersimulationen und analytischen Rechnungen in einfachen und komplexen Systemen. In den letzten Jahrzehnten ist viel auf dem Gebiet der Komplexitätstheorie geforscht worden, und es gibt zahlreiche Definitionen von Komplexität. In dieser Arbeit wird das Attribut komplex aufgrund zweier Aspekte vergeben: Einerseits sprechen wir von einem komplexen System, wenn es sich aus vielen untereinander wechselwirkenden einfachen Systemen zusammensetzt. Aus dieser Perspektive ist jedes von uns betrachtete System komplex, allerdings ist die...

IAM-Bernet-Studie Journalisten im Internet 2009 : eine repräsentative Befragung von Schweizer Medienschaffenden zum beruflichen Umgang mit dem Internet

Marcel Bernet & Guido Keel
Für Schweizer Journalistinnen und Journalisten sind Webseiten mittlerweile wichtiger als Tageszeitungen oder das persönliche Gespräch. Google dominiert die Online-Suche und beeinflusst damit auch die Themenfindung der Medien. Die «IAM/Bernet-Studie Journalisten im Internet 2009» zeigt eine überraschend hohe Akzeptanz Sozialer Netzwerke: Bereits über 40 Prozent der Schweizer Medienschaffenden nutzen Plattformen wie Facebook für ihre Arbeit. Unter den benutzten Online-Werkzeugen dringt Wikipedia auf den fünften Wichtigkeits-Platz vor. Noch keine Relevanz erreicht Twitter. Schweizer Medienschaffende glauben, dass der...

Construct Validity of Cognitive Reserve in a Multiethnic Cohort: The Northern Manhattan Study

Karen L. Siedlecki, Yaakov Stern, Aaron Reuben, Ralph L. Sacco, Mitchell S. Elkind & Clinton B. Wright
Cognitive reserve is a hypothetical construct that has been used to inform models of cognitive aging and is presumed to be indicative of life experiences that may mitigate the effects of brain pathology. The purpose of this study was to evaluate the construct validity of cognitive reserve by examining both its convergent and its discriminant validity across three different samples of participants using structural equation modeling. The cognitive reserve variables were found to correlate highly...

Comparison of Patient and Caregiver Reports of Patient Activity Participation and Its Relationship to Mental Health in Patients with Alzheimer's Disease

Karen L. Siedlecki, Oksana Tatarina-Nulman, Linda Sanders, Marilyn Albert, Deborah Blacker, Bruno Dubois, Jason Brandt & Yaakov Stern
The relationship between engagement in pleasant activities as rated by the patient and as rated by the caregiver from the patient's perspective was examined using structural equation modeling in a sample of patients (N = 277) diagnosed with mild to moderate Alzheimer's disease. The two activity participation ratings were only moderately related to one another. Furthermore, depression was the only significant predictor of the patient-rated activity participation, whereas severity of depression, degree of personality change,...

Cognitive Reserve

Yaakov Stern
The concept of reserve has been proposed to account for the disjunction between the degree of brain damage and its clinical outcome. This paper attempts to produce a coherent theoretical account the reserve in general and of cognitive reserve in particular. It reviews epidemiologic data supporting the concept of cognitive reserve, with a particular focus of its implications for aging and dementia. It then focuses on methodologic issues that are important when attempting to elucidate...

Bridging from Clinical Endpoints to Estimates of Treatment Value for External Decision Makers

Carolyn W. Zhu, Christopher Leibman, Raymond Townsend, Trent McLaughlin, Nikolaos Scarmeas, Marilyn Albert, Jason Brandt, Deborah Blacker, Mary Sano & Yaakov Stern
AIM: While clinical endpoints provide important information on the efficacy of treatment in controlled conditions, they often are not relevant to decision makers trying to gauge the potential economic impact or value of new treatments. Therefore, it is often necessary to translate changes in cognition, function or behavior into changes in cost or other measures, which can be problematic if not conducted in a transparent manner. The Dependence Scale (DS), which measures the level of...

Bias Effects in the Possible/Impossible Object Decision Test with Matching Objects

Anja Soldan, John Hilton & Yaakov Stern
In the possible/impossible object decision test, priming has consistently been found for structurally possible, but not impossible, objects, leading Schacter, Cooper, and Delaney (1990) to suggest that priming relies on a system that represents the global 3-D structure of objects. Using a modified design with matching objects to control for the influence of episodic memory, Ratcliff and McKoon (1995) and Williams and Tarr (1997) found negative priming for impossible objects (i.e., lower performance for old...

Age Effects on Load-Dependent Brain Activations in Working Memory for Novel Material

Roee Holtzer, Brian C. Rakitin, Jason Steffener, Joseph Flynn, Arjun Kumar & Yaakov Stern
Three competing models of cognitive aging (neural compensation, capacity limitations, neural inefficiency) were examined in relation to working memory for novel non-verbal material. To accomplish this goal young (n = 25) and old (n = 25) participants performed a delayed item recognition (DIR) task while being scanned with bold fMRI. The stimuli in the DIR task consisted of computer-generated closed-curve shapes with each shape presented only once in the testing conditions of each participant. This...

Extracurricular participation and favorable academic outcomes : a correlational study comparing the relationship for students with and without educational disabilities

Jeffrey A Reiser
Ronald E. Reeve, Advisor This study examines the predictive value ofschool-based extracurricular activity participation for academic engagement, attendance, attitude towards school, school connectedness, and educational aspirations, with particular ·emphasis on this relationship for students with educational disabilities. The results indicated extracurricular involvement as associated with a significant percentage ofthe variance and as significantly improving the strength ofprediction for all 5 outcome variables beyond the predictive strength of socioeconomic status. Results suggest increased extracurricular involvement predicts...

William Weeks and the ephemeral temple at Nauvoo

Steven Daniel Cornell
(:unav)

La República Argentina: El Debate Sobre La Guerra Civil Y La Inmigración

Lidia Bocanegra Barbecho
El presente capítulo planteará cuestiones del porqué Argentina no fue un país de acogida para el exilio republicano, salvaguardándose detrás de una política restrictiva inmigratoria en consonancia con el rol de su neutralismo con ambas guerras: tanto la española como, prácticamente, todo el desarrollo de la Segunda Guerra Mundial. Del porqué la figura del refugiado se convierte en un inmigrante indeseable, en una sociedad en donde la gran mayoría de su población lo consideraba precisamente...

La República Argentina: El Debate Sobre La Guerra Civil Y La Inmigración

Lidia Bocanegra Barbecho
El presente capítulo planteará cuestiones del porqué Argentina no fue un país de acogida para el exilio republicano, salvaguardándose detrás de una política restrictiva inmigratoria en consonancia con el rol de su neutralismo con ambas guerras: tanto la española como, prácticamente, todo el desarrollo de la Segunda Guerra Mundial. Del porqué la figura del refugiado se convierte en un inmigrante indeseable, en una sociedad en donde la gran mayoría de su población lo consideraba precisamente...

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