Mike Matthews wrote several sexist and racist blog posts a decade ago that were recently unearthed.

The state's board of education had renewed Commissioner Pam Stewart's contract for a year before the midterm election but after the election of a new Republican governor, she said she'd leave in January instead.

Florida's governor signed a bill that will allow schools to arm classroom teachers, part of a longer list of school safety changes made after a school shooting in Parkland, Fla., last year.

Idaho officials asked a U.S. Supreme Court justice to block an injunction that allows a group backing an education ballot initiative to collect electronic signatures because of COVID-19.

The U.S. Supreme Court blocked an injunction that had allowed a group backing an Idaho education spending measure to collect electronic signatures because of the coronavirus pandemic.

Alexandria Area High School was created to accommodate changes in education and technology.

State Education Secretary Rebecca Holcombe has been officiating over the state's politically thorny district consolidation process, and many are asking for it to be placed on hold until the state board replaces her.

30-year-old was acquired in a trade for Timothy Liljegren, was pointless in seven games with San Jose this season

Michael Martirano led the state's schools through dramatic budget cuts, academic challenges, and a state-versus-local battle over school construction.

In the aftermath of this spring's teacher protests, more educators are running for state office—and the National Education Association is seizing on the political moment.

Nov. 12—The Gonzaga women's basketball team has much to learn after a challenging loss at Stanford on Sunday. Losses have a way of exposing a team's shortcomings. And there is much to learn from the worst loss (89-58) in coach Lisa Fortier's 11 seasons. Stanford, unranked in the preseason poll for the first time since 1999-2000, is unranked no more. The Cardinal (3-0) entered at No. 24 in the ...

Robbert Havekes
Dec 12, 2012; 32:18137-18149
BehavioralSystemsCognitive

Prithviraj Rajebhosale
Oct 23, 2024; 44:e0063242024-e0063242024
Cellular

Mitchell G. Spring
Oct 9, 2024; 44:e0602242024-e0602242024
BehavioralSystemsCognitive

Serotonin modulates diverse phenotypes and functions including depressive, aggressive, impulsive, and feeding behaviors, all of which have reward-related components. To date, research has focused on understanding these effects by measuring and manipulating dorsal raphe serotonin neurons and using single-receptor approaches. These studies have led to a better understanding of the heterogeneity of serotonin actions on behavior; however, they leave open many questions about the timing and location of serotonin's actions modulating the neural circuits that drive these behaviors. Recent advances in genetically encoded fluorescent biosensors, including the GPCR activation-based sensor for serotonin (GRAB-5-HT), enable the measurement of serotonin release in mice on a timescale compatible with a single rewarding event without corelease confounds. Given substantial evidence from slice electrophysiology experiments showing that serotonin influences neural activity of the striatal circuitry, and the known role of the dorsal medial striatal (DMS) in reward-directed behavior, we focused on understanding the parameters and timing that govern serotonin release in the DMS in the context of reward consumption, external reward value, internal state, and cued reward. Overall, we found that serotonin release is associated with each of these and encodes reward anticipation, value, approach, and consumption in the DMS.

Abnormal neuronal morphological features, such as dendrite branching, axonal branching, and spine density, are thought to contribute to the symptoms of depression and anxiety. However, the role and molecular mechanisms of aberrant neuronal morphology in the regulation of mood disorders remain poorly characterized. Here, we show that neuritin, an activity-dependent protein, regulates the axonal morphology of serotonin neurons. Male neuritin knock-out (KO) mice harbored impaired axonal branches of serotonin neurons in the medial prefrontal cortex and basolateral region of the amygdala (BLA), and male neuritin KO mice exhibited depressive and anxiety-like behaviors. We also observed that the expression of neuritin was decreased by unpredictable chronic stress in the male mouse brain and that decreased expression of neuritin was associated with reduced axonal branching of serotonin neurons in the brain and with depressive and anxiety behaviors in mice. Furthermore, the stress-mediated impairments in axonal branching and depressive behaviors were reversed by the overexpression of neuritin in the BLA. The ability of neuritin to increase axonal branching in serotonin neurons involves fibroblast growth factor (FGF) signaling, and neuritin contributes to FGF-2-mediated axonal branching regulation in vitro. Finally, the oral administration of an FGF inhibitor reduced the axonal branching of serotonin neurons in the brain and caused depressive and anxiety behaviors in male mice. Our results support the involvement of neuritin in models of stress-induced depression and suggest that neuronal morphological plasticity may play a role in controlling animal behavior.

Neuregulin1 (Nrg1) signaling is critical for neuronal development and function from fate specification to synaptic plasticity. Type III Nrg1 is a synaptic protein which engages in bidirectional signaling with its receptor ErbB4. Forward signaling engages ErbB4 phosphorylation, whereas back signaling engages two known mechanisms: (1) local axonal PI3K-AKT signaling and (2) cleavage by -secretase resulting in cytosolic release of the intracellular domain (ICD), which can traffic to the nucleus (Bao et al., 2003; Hancock et al., 2008). To dissect the contribution of these alternate signaling strategies to neuronal development, we generated a transgenic mouse with a missense mutation (V₃₂₁L) in the Nrg1 transmembrane domain that disrupts nuclear back signaling with minimal effects on forward signaling or local back signaling and was previously found to be associated with psychosis (Walss-Bass et al., 2006). We combined RNA sequencing, retroviral fate mapping of neural stem cells, behavioral analyses, and various network analyses of transcriptomic data to investigate the effect of disrupting Nrg1 nuclear back signaling in the dentate gyrus (DG) of male and female mice. The V₃₂₁L mutation impairs nuclear translocation of the Nrg1 ICD and alters gene expression in the DG. V₃₂₁L mice show reduced stem cell proliferation, altered cell cycle dynamics, fate specification defects, and dendritic dysmorphogenesis. Orthologs of known schizophrenia (SCZ)-susceptibility genes were dysregulated in the V₃₂₁L DG. These genes coordinated a larger network with other dysregulated genes. Weighted gene correlation network analysis and protein interaction network analyses revealed striking similarity between DG transcriptomes of V₃₂₁L mouse and humans with SCZ.

Neuroinflammation can positively influence axon regeneration following injury in the central nervous system. Inflammation promotes the release of neurotrophic molecules and stimulates intrinsic proregenerative molecular machinery in neurons, but the detailed mechanisms driving this effect are not fully understood. We evaluated how microRNAs are regulated in retinal neurons in response to intraocular inflammation to identify their potential role in axon regeneration. We found that miR-383-5p is downregulated in retinal ganglion cells in response to zymosan-induced intraocular inflammation. MiR-383-5p downregulation in neurons is sufficient to promote axon growth in vitro, and the intravitreal injection of a miR-383-5p inhibitor into the eye promotes axon regeneration following optic nerve crush. MiR-383-5p directly targets ciliary neurotrophic factor (CNTF) receptor components, and miR-383-5p inhibition sensitizes adult retinal neurons to the outgrowth-promoting effects of CNTF. Interestingly, we also demonstrate that CNTF treatment is sufficient to reduce miR-383-5p levels in neurons, constituting a positive-feedback module, whereby initial CNTF treatment reduces miR-383-5p levels, which then disinhibits CNTF receptor components to sensitize neurons to the ligand. Additionally, miR-383-5p inhibition derepresses the mitochondrial antioxidant protein peroxiredoxin-3 (PRDX3) which was required for the proregenerative effects associated with miR-383-5p loss-of-function in vitro. We have thus identified a positive-feedback mechanism that facilitates neuronal CNTF sensitivity in neurons and a new molecular signaling module that promotes inflammation-induced axon regeneration.

It is well established that holding information in working memory (WM) elicits sustained stimulus-specific patterns of neural activity. Nevertheless, here we provide evidence for a distinct class of neural activity that tracks the number of individuated items in working memory, independent of the type of visual features stored. We present two EEG studies of young adults of both sexes that provide robust evidence for a signal tracking the number of individuated representations in working memory, regardless of the specific feature values stored. In Study 1, subjects maintained either colors or orientations across separate blocks in a single session. We found near-perfect generalization of the load signal between these two conditions, despite being able to simultaneously decode which feature had been voluntarily stored. In Study 2, participants attended to two features with very distinct cortical representations: color and motion coherence. We again found evidence for a neural load signal that robustly generalized across these distinct visual features, even though cortically disparate regions process color and motion coherence. Moreover, representational similarity analysis provided converging evidence for a content-independent load signal, while simultaneously showing that unique variance in EEG activity tracked the specific features that were stored. We posit that this load signal reflects a content-independent "pointer" operation that binds objects to the current context while parallel but distinct neural signals represent the features that are stored for each item in memory.

Odor information arrives first in the main olfactory bulb and is then broadcasted to the olfactory cortices and striatum. Downstream regions have unique cellular and connectivity architectures that may generate different coding patterns to the same odors. To reveal region-specific response features, tuning and decoding of single-unit populations, we recorded responses to the same odors under the same conditions across regions, namely, the main olfactory bulb (MOB), the anterior olfactory nucleus (AON), the anterior piriform cortex (aPC), and the olfactory tubercle of the ventral striatum (OT), of awake male mice. We focused on chemically closely related aldehydes that still create distinct percepts. The MOB had the highest decoding accuracy for aldehydes and was the only region encoding chemical similarity. The MOB had the highest fraction of inhibited responses and narrowly tuned odor-excited responses in terms of timing and odor selectivity. Downstream, the interconnected AON and aPC differed in their response patterns to the same stimuli. While odor-excited responses dominated the AON, the aPC had a comparably high fraction of odor-inhibited responses. Both cortices share a main output target that is the MOB. This prompted us to test if the two regions convey also different net outputs. Aldehydes activated AON terminals in the MOB as a bulk signal but inhibited those from the aPC. The differential cortical projection responses generalized to complex odors. In summary, olfactory regions reveal specialized features in their encoding with AON and aPC differing in their local computations, thereby generating inverse net centrifugal and intercortical outputs.

Key event-related potentials (ERPs) of perceptual decision-making such as centroparietal positivity (CPP) elucidate how evidence is accumulated toward a given choice. Furthermore, this accumulation can be impacted by visual target selection signals such as the N2 contralateral (N2c). How these underlying neural mechanisms of perceptual decision-making are influenced by the spatial congruence of distractors relative to target stimuli remains unclear. Here, we used electroencephalography (EEG) in humans of both sexes to investigate the effect of distractor spatial congruency (same vs different hemifield relative to targets) on perceptual decision-making. We confirmed that responses for perceptual decisions were slower for spatially incongruent versus congruent distractors of high salience. Similarly, markers of target selection (N2c peak amplitude) and evidence accumulation (CPP slope) were found to be lower when distractors were spatially incongruent versus congruent. To evaluate the effects of congruency further, we applied drift diffusion modeling to participant responses, which showed that larger amplitudes of both ERPs were correlated with shorter nondecision times when considering the effect of congruency. The modeling also suggested that congruency's effect on behavior occurred prior to and during evidence accumulation when considering the effects of the N2c peak and CPP slope. These findings point to spatially incongruent distractors, relative to congruent distractors, influencing decisions as early as the initial sensory processing phase and then continuing to exert an effect as evidence is accumulated throughout the decision-making process. Overall, our findings highlight how key electrophysiological signals of perceptual decision-making are influenced by the spatial congruence of target and distractor.

Systemic study of pathogenic pathways and interrelationships underlying genes associated with Alzheimer's disease (AD) facilitates the identification of new targets for effective treatments. Recently available large-scale multiomics datasets provide opportunities to use computational approaches for such studies. Here, we devised a novel disease gene identification (digID) computational framework that consists of a semi-supervised deep learning classifier to predict AD-associated genes and a protein–protein interaction (PPI) network-based analysis to prioritize the importance of these predicted genes in AD. digID predicted 1,529 AD-associated genes and revealed potentially new AD molecular mechanisms and therapeutic targets including GNAI1 and GNB1, two G-protein subunits that regulate cell signaling, and KNG1, an upstream modulator of CDC42 small G-protein signaling and mediator of inflammation and candidate coregulator of amyloid precursor protein (APP). Analysis of mRNA expression validated their dysregulation in AD brains but further revealed the significant spatial patterns in different brain regions as well as among different subregions of the frontal cortex and hippocampi. Super-resolution STochastic Optical Reconstruction Microscopy (STORM) further demonstrated their subcellular colocalization and molecular interactions with APP in a transgenic mouse model of both sexes with AD-like mutations. These studies support the predictions made by digID while highlighting the importance of concurrent biological validation of computationally identified gene clusters as potential new AD therapeutic targets.

The precise regulation of Ca²⁺ signals plays a crucial role in the physiological functions of neurons. Here, we investigated the rapid effect of glucocorticoids on Ca²⁺ signals in cultured hippocampal neurons from both female and male rats. In cultured hippocampal neurons, glucocorticoids inhibited the spontaneous somatic Ca²⁺ spikes generated by Kv2.1-organized Ca²⁺ microdomains. Furthermore, glucocorticoids rapidly reduced the cell surface expressions of Kv2.1 and Ca_V1.2 channels in hippocampal neurons. In HEK293 cells transfected with Kv2.1 alone, glucocorticoids significantly reduced the surface expression of Kv2.1 with little effect on K⁺ currents. In HEK293 cells transfected with Ca_V1.2 alone, glucocorticoids inhibited Ca_V1.2 currents but had no effect on the cell surface expression of Ca_V1.2. Notably, in the presence of wild-type Kv2.1, glucocorticoids caused a decrease in the surface expression of Ca_V1.2 channels in HEK293 cells. However, this effect was not observed in the presence of nonclustering Kv2.1S586A mutant channels. Live-cell imaging showed that glucocorticoids rapidly decreased Kv2.1 clusters on the plasma membrane. Correspondingly, Western blot results indicated a significant increase in the cytoplasmic level of Kv2.1, suggesting the endocytosis of Kv2.1 clusters. Glucocorticoids rapidly decreased the intracellular cAMP concentration and the phosphorylation level of PKA in hippocampal neurons. The PKA inhibitor H89 mimicked the effect of glucocorticoids on Kv2.1, while the PKA agonist forskolin abrogated the effect. In conclusion, glucocorticoids rapidly suppress Ca_V1.2-mediated Ca²⁺ signals in hippocampal neurons by promoting the endocytosis of Kv2.1 channel clusters through reducing PKA activity.

Impaired inhibitory synapse development is suggested to drive neuronal hyperactivity in autism spectrum disorders (ASD) and epilepsy. We propose a novel mechanism by which astrocytes control the development of parvalbumin (PV)-specific inhibitory synapses in the hippocampus, implicating ephrin-B/EphB signaling. Here, we utilize genetic approaches to assess functional and structural connectivity between PV and pyramidal cells (PCs) through whole-cell patch–clamp electrophysiology, optogenetics, immunohistochemical analysis, and behaviors in male and female mice. While inhibitory synapse development is adversely affected by PV-specific expression of EphB2, a strong candidate ASD risk gene, astrocytic ephrin-B1 facilitates PV->PC connectivity through a mechanism involving EphB signaling in PV boutons. In contrast, the loss of astrocytic ephrin-B1 reduces PV->PC connectivity and inhibition, resulting in increased seizure susceptibility and an ASD-like phenotype. Our findings underscore the crucial role of astrocytes in regulating inhibitory circuit development and discover a new role of EphB2 receptors in PV-specific inhibitory synapse development.

FAO Director-General José Graziano da Silva today expressed confidence that “significant progress against hunger, food insecurity and malnutrition,” will be achieved in the next four years. He made the [...]

The Publications branch now offers monthly publications updates in French to ensure you get the most up-to-date FAO’s knowledge products.   

The newsletter highlights the key publications available in French and [...]

The monthly publications updates produced by the Publications branch of the FAO Office of Communications are now available in English, Chinese and French.  

The newsletters highlight key publications available in the respective [...]

Three sites in China - an ancient tea-producing area, a nomadic livestock-rearing region and a rain-fed stone terrace farming system - were formally recognised  as Globally Important Agricultural Heritage [...]

Rome - Two new sites in Japan - an inland fisheries and associated paddy farming system centred on the country’s largest lake and a traditional fruit-growing area  believed to have been the [...]

The monthly FAO publications updates produced by the Publications Branch of the FAO Office of Communications are available in English, French and Chinese.

The newsletters highlight key publications available [...]

The monthly FAO publications updates produced by the Publications Branch of the FAO Office of Communications are available in English, French and Chinese.

The newsletters highlight key publications available [...]

Interpretive exhibits coordinator Steven Madewells demonstrates a few experiments at Spark!Lab, an interactive exhibit at the National Museum of American History. Read more at: https://www.smithsonianmag.com/smithsonian-institution/theres-nothing-like-a-sparklab-to-ignite-the-imagination-1-180949007/

We're over here making podcasts, and you're over there listening. Let's bridge that gap! We want to know more about you, like: why you're listening, what your favorite topics are, and what Smithsonian magazine can do to make "There's More to That" even better. Tell us what you think at  smithsonianmag.com/podcastsurvey (https://www.smithsonianmag.com/podcastsurvey) .

The curators at the American History museum delve into the archives to show artifacts from the 1960 election.

More on biomimicry: http://j.mp/RI3OOB Scientists believe the iridescent wings of the morphos butterfly could be used in technology to benefit humans.

A melting glacier caused a mountain in Greenland to collapse into a narrow fjord, setting off an oscillating wave that rattled seismic detectors around the world

Archaeologists unearthed a series of mudbrick rooms filled with religious tributes, soldiers' personal effects, engraved weaponry and animal bones

The vertical sign stretched across three stories of the Manhattan hotel, which once welcomed the likes of Bob Dylan, Patti Smith, Andy Warhol and Janis Joplin

Researchers recently identified James Fitzjames, a captain on the ill-fated HMS Erebus that went looking for the Northwest Passage in 1845

Scientists sent bioengineered heart tissue samples to the ISS to study how to keep astronauts safe during future long-term space travel

An increasing number of people in France espouse a clothing-free lifestyle

Monday marks the first Remembrance Day ceremony at the National War Memorial in St. John's to include the tomb of the Unknown Soldier. We're proud to present again two documentaries that tell a remarkable story.

Elections Nova Scotia is investigating PC candidate Susan Corkum-Greek's campaign to determine whether it broke the law by handing out gift cards on Saturday outside a Tim Hortons in Lunenburg, N.S. 

Atlantic salmon returns were at their lowest level ever this year, say researchers, who are nevertheless refusing to give up hope that the population can rebound.

Inflation, an increase to the debt limit, and a series of mega-projects have been focuses of the municipal election in Regina.

The apartment once occupied by the author of Les Miserables is now a museum dedicated to his life and to 19th century Paris

P.E.I.'s capital budget has allocated $2.5 million to build up to five provincially owned cellphone towers, but so far no telecommunications companies have committed to using them.

The Town of Kensington, P.E.I., has committed to implementing a new campaign to end gender-based violence.