The Role of the Spleen in Lymphocyte Migration

In all species studied so far it was found that more lymphocytes migrate to the spleen than to all the lymph nodes together. Specific molecules on lymphocytes and endothelial cells regulate their entry into lymph nodes, but none of the known molecules play a role in homing to the spleen. The splenic compartments, comprising the red pulp, marginal zone, periarterial lymphatic sheath (PALS) and follicles, all show different kinetics for migrating lymphocytes. By combining 51Cr lymphocyte labeling with morphometry and two color immunohistochemistry, the migratory route of lymphocyte subsets can be followed through the spleen and absolute numbers of lymphocytes calculated in each compartment. T lymphocytes home preferentially to the PALS and B lymphocytes home not only to follicles but also in large numbers to the marginal zone and red pulp. CD4+ and CD8+ lymphocytes migrate similarly at early time points, but at 24 hours CD4+ lymphocytes are preferentially found in the PALS with CD8+ lymphocytes in the red pulp and marginal zone. The functional significance of the different routes of lymphocytes through the spleen has yet to be defined in relationship to specific immune functions and regulatory factors on splenic lymphocyte homing

Weed seed predation in organic and conventional cereal fields

Granivores can consume a large proportion of newly produced weed seeds in crop fields each year. If substantial, granivores can help to exhaust the seed bank and thus contribute to long-term weed control. In northern Germany, however, annual seed losses tend to be smaller and granivore density lower than elsewhere. To investigate if high land-use intensity could be involved, seed predation rates were measured using Lolium multiflorum Lam. as a model seed in three organic and three conventional cereal fields located close to each other. In addition, seed predation was measured at different distances from the field edge and exclosure cages were used to determine the relative contributions of vertebrates and invertebrates to seed consumption.As expected for cereal crops, seed predation rates increased from early spring to early summer and then decreased again. Seed predation by invertebrates was comparable to that in other studies, but seed predation by vertebrates, mainly rodents, was much lower, suggesting that low seed predation rates in northern Germany may have been caused by lower mouse activity, concurring with low mouse density. Results with regard to the effect of distance to the field edge were variable and difficult to interpret. Observed responses may be linked to predator identity, with rodents foraging preferentially near field edges, and invertebrates away from field edges or indifferently. Farming system (organic vs. conventional) had little or no effect on seed predation rates.Reasons for the low density of seed predators and low seed predation rates observed are unknown, but it is likely that some unidentified detrimental factor is involved in the organic fields or the impoverished landscape as a whole. Keywords: Biological weed control, carabid beetles, distance to field edge, farming system, miceSamenfraß in Getreide auf ökologisch und konventionell bewirtschafteten FeldernSamenfraß durch Granivoren kann zu hohem Verlust neuproduzierter Unkrautsamen führen. Falls dies in beträchtlichem Maße geschieht, verringert Samenfraß den Samenbankeintrag substantiell und trägt damit zur langfristigen Unkrautregulierung bei. In Norddeutschland scheinen die jährlichen Samenverluste und die Prädatorendichten jedoch geringer zu sein als anderenorts. Um zu untersuchen, ob die hohe Landnutzungsintensität hierfür ursächlich sein könnte, wurden Samenfraßraten unter Nutzung von Lolium multiflorum Lam. als Modellsamen auf drei ökologisch und drei konventionell bewirtschafteten, räumlich nah beieinander liegenden Getreidefeldern ermittelt. Darüber hinaus wurde der Samenfraß in unterschiedlichen Abständen zum Feldrand erfasst. Ausschlusskäfige wurden genutzt, um zwischen dem Samenfraß durch Vertebraten und Invertebraten unterscheiden zu können.Wie im Getreideanbau zu erwarten, stieg die Samenfraßrate vom Frühling bis zum Sommer an und sank dann wieder. Der Samenfraß durch Invertebraten war vergleichbar mit dem anderer Studien. Die Samenprädation durch Vertebraten, hier hauptsächlich Nagetiere, war hingegen deutlich niedriger, ebenso die erfasste Aktivitätsdichte. Die zu beobachtenden niedrigen Samenfraßraten in Norddeutschland könnten demnach durch niedrige Vertebraten-Aktivitätsdichten beeinflusst sein. Die Ergebnisse bezüglich der Wirkung des Feldrandabstands waren unterschiedlich und schwer zu interpretieren. Die beobachteten Unterschiede könnten mit der Prädatorenart zusammenhängen, da Nagetiere bei der Nahrungssuche Feldränder und Invertebraten mehr die Feldmitte bevorzugen oder überall zu finden sind. Die Bewirtschaftungsform (ökologisch vs. konventionell) hatte wenig oder keinen Einfluss auf die Samenfraßraten.Die Gründe für die beobachteten geringen Samenprädatorendichten und Samenfraßraten sind unbekannt,aber es ist wahrscheinlich, das gegenteilig wirkende Einflüsse auf den ökologischen Feldern oder die verarmte Landschaft als Ganzes als Ursache in Frage kommen.Stichwörter: Abstand zum Feldrand, Bewirtschaftungsformen, Biologische Unkrautbekämpfung, Laufkäfer, Mäus

The Social Media Affinity Scale: Implications For Education

In recent years, males and females have demonstrated fairly equal amounts of internet usage, but females have demonstrated higher usage of social media sites. These observed differences served as the impetus for the current study. A survey was conducted in early 2010 among college students to assess whether differences still occur between males and females, and specifically with regard to social media usage. In order to assess these phenomena, the Social Media Affinity Scale was created and deployed. Results of the study showed that, among the students surveyed, no significant differences exist between males and females in their internet usage, social media usage, and also beliefs about social media sites in general. Given that students have overwhelmingly adopted social media, we propose that there is now an opportunity to leverage social media in college courses to deliver content and engage students in ways not previously possible

Is Tasting Believing? The Effect Of Peel-And-Taste Advertising On Product Feelings And Likelihood Of Purchase

Scratch-and-sniff product samples have been used as surrogate methods of inducing product trial since the 1990s, but to date tasting a product required either in-store or in-home interactions with actual products. Peel-and-Taste flavor strips were introduced in 2007 as a means of putting product sample substitutes in the hands of many by virtue of being attached to advertising pieces in magazines, newspaper blow-ins, and direct mail. This study utilized a sample of female consumers (the targeted recipients of the ads) to allow them to interact with advertising samples using Peel-and-Taste, and measuring various resulting attitudes. Results showed that ratings of flavor pleasantness and the Peel-and-Taste method itself were positive significant predictors of Feelings Toward the Product (FTP), and that  FTP and the participant’s resulting mood state were positive significant predictors of Likelihood To Purchase (LTP) the product. In aggregate, though, FTP was modest at best, and LTP was virtually indifferent. It was concluded that the Peel-and-Taste method, while favorably linked to FTP and LTP, was not so strong as to be a significant stimulus to purchase the product

Ive Got The Music In Me: A Study Of Peak Musical Memory Age And The Implications For Future Advertising

Neuropsychologists have demonstrated the effect music has on the human brain, and that a peak “musical memory age” occurs around 14, when normal bodily maturation is in progress. A group of 114 college students between the ages of 19 and 25 was exposed to short clips of the top 20 songs from each of the 11 years during their youth; participants were asked to rate their liking of each song sample on a 0-10 scale. Data analysis showed that the peak musical memory age of these students was not as precise as prior research had shown, and that overall there was difference in degree of musical affinity between age groups in the sample. This deviation from prior findings may have resulted from changes in how music is available today. Whereas specifically targeted music was once standard procedure in past TV advertising, these findings produce new implications for future TV advertising

Growth and saturation of the Kelvin-Helmholtz instability with parallel and anti-parallel magnetic fields

We investigate the Kelvin-Helmholtz instability occuring at the interface of a shear flow configuration in 2D compressible magnetohydrodynamics (MHD). The linear growth and the subsequent non-linear saturation of the instability are studied numerically. We consider an initial magnetic field aligned with the shear flow, and analyze the differences between cases where the initial field is unidirectional everywhere (uniform case), and where the field changes sign at the interface (reversed case). We recover and extend known results for pure hydrodynamic and MHD cases with a discussion of the dependence of the non-linear saturation on the wavenumber, the sound Mach number, and the Alfvenic Mach number for the MHD case. A reversed field acts to destabilize the linear phase of the Kelvin-Helmholtz instability compared to the pure hydrodynamic case, while a uniform field suppresses its growth. In resistive MHD, reconnection events almost instantly accelerate the buildup of a global plasma circulation. They play an important role throughout the further non-linear evolution as well, since the initial current sheet gets amplified by the vortex flow and can become unstable to tearing instabilities forming magnetic islands. As a result, the saturation behaviour and the overall evolution of the density and the magnetic field is markedly different for the uniform versus the reversed field case

Rubber friction: role of the flash temperature

When a rubber block is sliding on a hard rough substrate, the substrate asperities will exert time-dependent deformations of the rubber surface resulting in viscoelastic energy dissipation in the rubber, which gives a contribution to the sliding friction. Most surfaces of solids have roughness on many different length scales, and when calculating the friction force it is necessary to include the viscoelastic deformations on all length scales. The energy dissipation will result in local heating of the rubber. Since the viscoelastic properties of rubber-like materials are extremely strongly temperature dependent, it is necessary to include the local temperature increase in the analysis. At very low sliding velocity the temperature increase is negligible because of heat diffusion, but already for velocities of order 0.01 m/s the local heating may be very important. Here I study the influence of the local heating on the rubber friction, and I show that in a typical case the temperature increase results in a decrease in rubber friction with increasing sliding velocity for v > 0.01 m/s. This may result in stick-slip instabilities, and is of crucial importance in many practical applications, e.g., for the tire-road friction, and in particular for ABS-breaking systems.Comment: 22 pages, 27 figure

Insular cortex activity and the evocation of laughter

The insular cortex is fundamentally involved in the processing of interoceptive information. It has been postulated that the integrative monitoring of the bodily responses to environmental stimuli is crucial for the recognition and experience of emotions. Because emotional arousal is known to be closely coupled to functions of the anterior insula, we suspected laughter to be associated primarily with neuronal activity in this region. An anatomically constrained re-analysis of our imaging data pertaining to ticklish laughter, to inhibited ticklish laughter, and to voluntary laughter revealed regional differences in the levels of neuronal activity in the posterior and mid-/anterior portions of the insula. Ticklish laughter was associated specifically with right ventral anterior insular activity, which was not detected under the other two conditions. Hence, apparently, only laughter that is evoked as an emotional response bears the signature of autonomic arousal in the insular cortex

A mitochondrial-focused genetic interaction map reveals a scaffold-like complex required for inner membrane organization in mitochondria.

To broadly explore mitochondrial structure and function as well as the communication of mitochondria with other cellular pathways, we constructed a quantitative, high-density genetic interaction map (the MITO-MAP) in Saccharomyces cerevisiae. The MITO-MAP provides a comprehensive view of mitochondrial function including insights into the activity of uncharacterized mitochondrial proteins and the functional connection between mitochondria and the ER. The MITO-MAP also reveals a large inner membrane-associated complex, which we term MitOS for mitochondrial organizing structure, comprised of Fcj1/Mitofilin, a conserved inner membrane protein, and five additional components. MitOS physically and functionally interacts with both outer and inner membrane components and localizes to extended structures that wrap around the inner membrane. We show that MitOS acts in concert with ATP synthase dimers to organize the inner membrane and promote normal mitochondrial morphology. We propose that MitOS acts as a conserved mitochondrial skeletal structure that differentiates regions of the inner membrane to establish the normal internal architecture of mitochondria

Soil management practices

Soil management practices affect soil resources obviously, but those practices also affect water and air resources and the plants and animals that depend upon those resources. Good soil management builds soil quality, maintains or improves water and air quality, and supports plant, animal, and human life (NRCS, 1996a). Minimizing soil erosion, increasing water infiltration, and promoting biological activity through good management ultimately produces a soil with physical and chemical characteristics consistent with parent material, topography, and climat