Linear Self-Motion Cues Support the Spatial Distribution and Stability of Hippocampal Place Cells

The vestibular system provides a crucial component of place-cell and head-direction cell activity [1-7]. Otolith signals are necessary for head-direction signal stability and associated behavior [8, 9], and the head-direction signal's contribution to parahippocampal spatial representations [10-14] suggests that place cells may also require otolithic information. Here, we demonstrate that self-movement information from the otolith organs is necessary for the development of stable place fields within and across sessions. Place cells in otoconia-deficient tilted mice showed reduced spatial coherence and formed place fields that were located closer to environmental boundaries, relative to those of control mice. These differences reveal an important otolithic contribution to place-cell functioning and provide insight into the cognitive deficits associated with otolith dysfunction

Long-term deficits in cortical circuit function after asphyxial cardiac arrest and resuscitation in developing rats

AbstractCardiac arrest is a common cause of global hypoxic-ischemic brain injury. Poor neurologic outcome among cardiac arrest survivors results not only from direct cellular injury but also from subsequent long-term dysfunction of neuronal circuits. Here, we investigated the long-term impact of cardiac arrest during development on the function of cortical layer IV (L4) barrel circuits in the rat primary somatosensory cortex. We used multielectrode single-neuron recordings to examine responses of presumed excitatory L4 barrel neurons to controlled whisker stimuli in adult (8 ± 2-mo-old) rats that had undergone 9 min of asphyxial cardiac arrest and resuscitation during the third postnatal week. Results indicate that responses to deflections of the topographically appropriate principal whisker (PW) are smaller in magnitude in cardiac arrest survivors than in control rats. Responses to adjacent whisker (AW) deflections are similar in magnitude between the two groups. Because of a disproportionate decrease in PW-evoked responses, receptive fields of L4 barrel neurons are less spatially focused in cardiac arrest survivors than in control rats. In addition, spiking activity among L4 barrel neurons is more correlated in cardiac arrest survivors than in controls. Computational modeling demonstrates that experimentally observed disruptions in barrel circuit function after cardiac arrest can emerge from a balanced increase in background excitatory and inhibitory conductances in L4 neurons. Experimental and modeling data together suggest that after a hypoxic-ischemic insult, cortical sensory circuits are less responsive and less spatially tuned. Modulation of these deficits may represent a therapeutic approach to improving neurologic outcome after cardiac arrest.</jats:p

Affirmative Action and Utility Theory

Blacks have been discriminated against for many decades in the United States. In 1964, the Equal Employment Opportunity Commission was created to eliminate discrimination in hiring practices. Affirmative action plans were later implemented to create equity in places of employment. Both affirmative action and the EEOC were designed to create equality of the races and eliminate racial tension in the United States

Ageism And The Baby Boomers: Issues, Challenges And The TEAM Approach

This paper considers the issues and challenges associated with ageism relating to the Baby Boomer generation in Corporate America.&nbsp; Stereotypes about older workers are examined along with types of discrimination facing Boomers.&nbsp; The TEAM approach is proposed to combat ageism in the workplace.&nbsp; The strategy includes using intergenerational teams, education and training, awareness, accountability, and accommodation and mentoring as key components

Tooth loss patterns in older adults with special needs: a Minnesota cohort

This study was conducted to detail tooth loss patterns in older adults with special needs. A total of 491 elderly subjects with special needs were retrospectively selected and followed during 10/1999-12/2006. Medical, dental, cognitive, and functional assessments were abstracted from dental records and used to predict risk of tooth loss. Tooth loss events were recorded for subjects during follow-up. Chi-squared tests were used to study the association between tooth loss and the selected risk factors. Logistic, poisson, and negative binomial regressions were developed to study tooth loss patterns. Overall, 27% of the subjects lost at least one tooth during follow-up. Fourteen subjects had tooth loss events per 100 person-years. Tooth loss pattern did not differ significantly among different special-needs subgroups (i.e. community-dwelling vs. long-term care, physically disabled vs. functionally independent). Special-needs subjects with three or more active dental conditions at arrival had more than twice the risk of losing teeth than those without any existing conditions. After adjusting other factors, the number of carious teeth or retained roots at arrival was a significant predictor of tooth loss for older adults with special needs (P=0.001). These findings indicate that appropriately managing active caries and associated conditions is important to prevent tooth loss for older adults with special needs

Optical Characterization of Chromophoric Dissolved Organic Matter (CDOM) and Fe(II) Concentrations in Soil Porewaters Along a Channel-Bank Transect in a Salt Marsh

Chromophoric dissolved organic matter (CDOM) optical properties were measured in surface and porewaters as a function of depth and distance from the channel in a transect up the bank in a southern California salt marsh. Higher absorbance coefficients and fluorescence intensities in porewaters at depth vs. surface waters and shallower porewaters suggest soil porewater is a reservoir of CDOM in the marsh. Higher values were observed at the marsh sites compared to the channel site, suggesting increased production and storage in the marsh sites, and reduced leaching into overlying surface waters, is occurring. Spectral slope ratios decreased with depth, consistent with more aromatic, higher molecular weight material in the deeper porewaters, possibly due to different bacterial processing in the anaerobic vs. aerobic zones. Fe(II) concentrations, indicative of anaerobic bacterial processing, increased significantly at depth to values \u3e 1000 μM, consistent with active anaerobic microbial processing occurring at depth. The transitions to higher reduced iron concentrations correlated with increased absorbance and fluorescence, suggesting processing by anaerobic iron-reducing bacteria in these deeper zones may not mineralize as much carbon as in the shallower aerobic zones. Alternatively, this may be due to reduction of solid iron oxides coated with organic matter releasing both DOM and Fe(II). The ratio of humic-like fluorescence to the absorption coefficient decreased with increasing iron concentration, possibly due to optical interference by iron species. Taken together, the data indicate that marsh sites in the salt marsh act as a reservoir for higher molecular weight, more aromatic organic matter

University Crime Alerts: Do They Contribute to Institutional Betrayal and Rape Myths?

Universities are mandated by the Clery Act (20 USC § 1092(f)) to publicize the occurrence of certain campus crimes. Many universities rely on “Crime Alert” emails to quickly and effectively communicate when a crime has occurred. However, communications of sexual crimes are often narrow (e.g., limited to stranger-perpetrated crimes) and misleading (e.g., containing safety tips that are not applicable to most types of sexual violence). The current paper presents the results of two studies that test the effects of reading crime alert emails on subsequent endorsement of rape myths and institutional betrayal. In Study 1, participants read a typical crime alert email describing a stranger-perpetrated crime, an alternative email describing an acquaintance-perpetrated crime, or a control email describing an event unrelated to interpersonal violence. Men were significantly more likely to endorse rape myths than were women in the control condition, but not in the typical or alternative email condition. In addition, results from Study 1 indicate that issuing crime alert emails following stranger-perpetrated sexual violence leads to a sense of institutional betrayal among students who have experienced acquaintance-perpetrated violence. In Study 2, participants read a typical crime alert email or an alternative digest email. Participants who read the typical email reported higher rape myth acceptance, but not institutional betrayal, than those who read the digest email. There were also significant gender differences in student opinions of each email that suggest the digest email format may serve as a useful tool for engaging male students in the issue of campus sexual violence. Taken together, these studies provide converging evidence that university communication regarding sexual violence can either perpetuate or positively influence attitudes towards sexual violence

Differential involvement of the microtubule cytoskeleton in insulin receptor substrate 1 (IRS-1) and IRS-2 signaling to AKT determines the response to microtubule disruption in breast carcinoma cells

The insulin receptor substrate (IRS) proteins serve as essential signaling intermediates for the activation of PI3K by both the insulin-like growth factor 1 receptor (IGF-1R) and its close family member, the insulin receptor (IR). Although IRS-1 and IRS-2 share significant homology, they regulate distinct cellular responses downstream of these receptors and play divergent roles in breast cancer. To investigate the mechanism by which signaling through IRS-1 and IRS-2 results in differential outcomes, we assessed the involvement of the microtubule cytoskeleton in IRS-dependent signaling. Treatment with drugs that either stabilize or disrupt microtubules reveal that an intact microtubule cytoskeleton contributes to IRS-2- but not IRS-1-mediated activation of AKT by IGF-1. Proximal IGF-1R signaling events, including IRS tyrosine phosphorylation and recruitment of PI3K, are not inhibited by microtubule disruption, indicating that IRS-2 requires the microtubule cytoskeleton at the level of downstream effector activation. IRS-2 colocalization with tubulin is enhanced upon Taxol-mediated microtubule stabilization, which, together with the signaling data, suggests that the microtubule cytoskeleton may facilitate access of IRS-2 to downstream effectors such as AKT. Of clinical relevance is that our data reveal that expression of IRS-2 sensitizes breast carcinoma cells to apoptosis in response to treatment with microtubule-disrupting drugs, identifying IRS-2 as a potential biomarker for the response of breast cancer patients to Vinca alkaloid drug treatment

Pledged into Harm: Sorority and Fraternity Members Face Increased Risk of Sexual Assault and Sexual Harassment

The purpose of this manuscript is to examine the risk of sexual exploitation (both assault and harassment) associated with sorority and fraternity membership on U.S. college campuses. The results from this study come from data collected through an online survey. Participants (N=883) at a large Pacific Northwestern university provided information related to their sorority or fraternity membership, experiences of sexual violence (i.e., assault and harassment), and alcohol use. We both replicated and extended past research. Corroborating prior research, Greek-affiliated students experienced higher rates of sexual assault than non-affiliated students. We extended past research by focusing on sexual harassment experiences within the Greek life culture. Both male and female Greek-affiliated students reported higher rates of sexual harassment particularly unwanted sexual attention, compared to their non-Greek-affiliated peers. We also found that both sorority membership and alcohol-related problems predicted unique variance in women’s exposure to nonconsensual sexual contact, attempted/completed rape, and unwanted sexual attention. Fraternity membership but not alcohol-related problems predicted unique variance in men’s exposure to nonconsensual sexual contact and unwanted sexual attention. Implications discussed include the short- and long-term consequences of Greek-affiliation, institutional betrayal, and addressing sexual exploitation within this culture. Also identified are limitations of the current study and future directions for research on sexual exploitation within Greek life

RASSF1A and the rs2073498 Cancer Associated SNP

RASSF1A is one of the most frequently inactivated tumor suppressors yet identified in human cancer. It is pro-apoptotic and appears to function as a scaffolding protein that interacts with a variety of other tumor suppressors to modulate their function. It can also complex with the Ras oncoprotein and may serve to integrate pro-growth and pro-death signaling pathways. A SNP has been identified that is present in approximately 29% of European populations [rs2073498, A(133)S]. Several studies have now presented evidence that this SNP is associated with an enhanced risk of developing breast cancer. We have used a proteomics based approach to identify multiple differences in the pattern of protein/protein interactions mediated by the wild type compared to the SNP variant protein. We have also identified a significant difference in biological activity between wild type and SNP variant protein. However, we have found only a very modest association of the SNP with breast cancer predisposition