Medgar Evers College

PKMζ, a persistently active atypical PKC (aPKC) isoform, is thought to maintain late-phase long-term potentiation (late-LTP) and long-term memory. However, PKMζ-knockout mice still exhibit hippocampal LTP and spatial memory while lacking neocortical LTP, questioning whether this kinase is fundamental to enduring synaptic potentiation and memory. Tsokas et al. (2016) showed the other aPKC, PKCι/λ, likely compensates for PKMζ during maintenance in the hippocampus of PKMζ-null mice. In wild-type mice, PKCι/λ drives early-LTP and short-term memory, while PKMζ compensates for PKCι/λ knockout by supporting both early- and late-phase processes. Here we show PKCι/λ persistently increases during maintenance in two mouse models: PKMζ-conditional knockout (cKO) mice, and double-knockout mice carrying both conditional deletion of PKCι/λ and constitutive loss of PKMζ. In the double-knockout mice, PKCι/λ was measured while the kinase was still present, prior to its inducible ablation, to characterize its compensatory upregulation in late-LTP before removal. To test whether this compensation was functional, we ablated PKCι/λ in the hippocampus of the double-knockout mice. The double-knockout eliminated late-LTP, whereas individual knockout of either aPKC alone showed normal-appearing LTP. Double-knockout also abolished spatial long-term memory without affecting short-term memory. Thus, when PKMζ is absent, PKCι/λ persists to maintain hippocampal late-LTP and long-term memory.

Is long-term memory maintained by stable synaptic structures or persistent biochemical action? PKMζ, a persistently active atypical PKC (aPKC), is thought to be crucial for maintaining the late phase of long-term potentiation (late-LTP) and long-term memory through sustained kinase action. However, PKMζ-knockout mice express hippocampal LTP and spatial memory while lacking neocortical LTP, calling into question whether persistent kinases and PKMζ are fundamental to LTP and memory. In Tsokas et al., 2016, we showed PKCι/λ, the other aPKC, is the most likely compensating PKC isoform in PKMζ-knockout mice. In wild-type mice, PKCι/λ is critical to the initial generation of early-LTP and short-term memory, and PKMζ compensates for genetic deletion of PKCι/λ by supporting both early- and late-phase processes. Here, we found PKCι/λ persists in LTP and long-term memory when PKMζ is genetically deleted. We tested whether PKCι/λ functionally compensates for the loss of PKMζ by genetically ablating both aPKCs. Whereas deleting PKMζ and PKCι/λ individually induces compensation, deleting both aPKCs abolishes hippocampal late-LTP. Hippocampal ι/λ-ζ-double-knockout eliminates spatial long-term memory but not short-term memory. Thus, in the absence of PKMζ, a second persistent biochemical process compensates to maintain late-LTP and long-term memory.

The impact of energy consumption on sustainable development remains a critical global concern that is deeply influenced by the progress and effectiveness of the ongoing energy transition. The primary objective of this study is to examine the impact of the energy transition (ET) an institutional quality index (IQI) on sustainable development (SD), along with other control variables, including globalization (GLOB), trade openness (TO), gross domestic product per capita (GDP), and economic structure (EcoStru), in E-7 economies from 1990 to 2022. To fulfill this objective, we employ the cross-sectional autoregressive distributive lags (CS-ARDL) technique to tackle issues such as heteroscedasticity, cross-sectional dependence, and interaction across sections caused by variations in slope. Similarly, for the robustness analysis and based on the results of cointegration tests, we employed the Fully Modified Ordinary Least Square (FMOLS) and Canonical Cointegrating Regression (CCR) cointegration models. The empirical findings reveal that the ET, TO, and IQI significantly influence improving sustainable development in the E-7 countries. Meanwhile, GLOB and GDP have been shown to have a detrimental environmental impact. To move toward truly sustainable development, E-7 countries should emphasize the transition to renewable energy and reinforce institutional governance to lessen their dependence on fossil fuels.

Abstract Prenatal exposure to metals is a significant concern, particularly in urban settings where environmental factors and maternal characteristics may contribute to varying exposure levels. Understanding the factors influencing metal concentrations in newborns is crucial for developing targeted interventions. This study assessed the association between maternal characteristics, including country of origin and residential factors, and prenatal metal exposure in newborns delivered at public hospitals in New York City. A cross-sectional analysis was conducted on 301 mother-newborn dyads. Meconium samples were collected and analyzed for ten metals using inductively coupled plasma mass spectrometry (ICP-MS). Concentrations of metals, including aluminum, iron, manganese, nickel, and lead, varied based on demographic variables in the study population. Asian and Spanish-speaking mothers had significantly higher lead concentrations compared to White and English-speaking mothers. No significant associations were found between maternal housing characteristics and metal concentrations, potentially due to participants predominantly residing in environmental justice areas. The findings suggest that prenatal metal exposure in this population may be influenced by prior exposures in the country of origin and socio-economic factors post-immigration. These insights highlight the need for targeted public health interventions to reduce prenatal metal exposure in vulnerable urban populations.

New solvent-free polymer electrolytes are proposed based on a linear perfluorinated copolymer synthesized by enzymatic methods. The system is biphasic and exhibits two distinct conductivity pathways for long-range Na+-cation migration.