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Additive manufacturing has become an important tool for fabricating advanced systems and devices for visible nanophotonics. However, the lack of simulation and optimization methods taking into account the essential physics of the optimization process leads to barriers for greater adoption. This issue can often result in sub-optimal optical responses in fabricated devices on both local and global scales. We propose that physics-informed design and optimization methods, and in particular physics-informed machine learning, are particularly well-suited to overcome these challenges by incorporating known physics, constraints, and fabrication knowledge directly into the design framework.

Doped semiconductors can exhibit metallic-like properties ranging from superconductivity to tunable localized surface plasmon resonances. Diamond is a wide-bandgap semiconductor that is rendered electronically active by incorporating a hole dopant, boron. While the effects of boron doping on the electronic band structure of diamond are well-studied, any link between charge carriers and plasmons has never been shown. Here, we report intervalence plasmons in boron-doped diamond, defined as collective electronic excitations between the valence subbands, opened up by the presence of holes. Evidence for these low-energy excitations is provided by valence electron energy loss spectroscopy and near-field infrared spectroscopy. The measured spectra are subsequently reproduced by first-principles calculations based on the contribution of intervalence band transitions to the dielectric function. Our calculations also reveal that the real part of the dielectric function exhibits a crossover characteristic of metallicity. These results suggest a new mechanism for inducing plasmon-like behavior in doped semiconductors, and the possibility of attaining such properties in diamond, a key emerging material for quantum information technologies. Doping diamond with boron is well known to change its electronic structure. Here, the authors reveal low-energy collective excitations in boron-doped diamond, which originate from intervalence band transitions. [ABSTRACT FROM AUTHOR]

Targeted nanoparticles offer potential to selectively deliver therapeutics to cells; however, their subcellular fate following endocytosis must be understood to properly design mechanisms of drug release. Here we describe a nanoparticle platform and associated cell-based assay to observe lysosome trafficking of targeted nanoparticles in live cells. The nanoparticle platform utilizes two fluorescent dyes loaded onto PEG-poly(glutamic acid) and PEG-poly(Lysine) block co-polymers that also comprise azide reactive handles on PEG termini to attach antibody-based targeting ligands. Fluorophores were selected to be pH-sensitive (pHrodo Red) or pH-insensitive (Alexafluor 488) to report when nanoparticles enter low pH lysosomes. Dye-labelled block co-polymers were further assembled into polyion complex micelle nanoparticles and crosslinked through amide bond formation to form stable nano-scaffolds for ligand attachment. Cell binding and lysosome trafficking was determined in live cells by fluorescence imaging in 96-well plates and quantification of red- and green-fluorescence signals over time. The platform and assay was validated for selection of optimal antibody-derived targeting ligands directed towards CD22 for nanoparticle delivery. Kinetic analysis of uptake and lysosome trafficking indicated differences between ligand types and the ligand with the highest lysosome trafficking efficiency translated into effective DNA delivery with nanoparticles bearing the optimal ligand. IMPACT STATEMENT: The ability of this pH-sensitive reporter platform to rapidly screen ligands in nanoparticle format will enable identification and production of targeted NPs with desired lysosome trafficking properties. [ABSTRACT FROM AUTHOR]

Fentanyl overdose is a survivable condition that commonly resolves without chronic overt changes in phenotype. While the acute physiological effects of fentanyl overdose, such as opioid-induced respiratory depression (OIRD) and Wooden Chest Syndrome, represent immediate risks of lethality, little is known about longer-term systemic or organ-level impacts for survivors. In this study, we investigated the effects of a single, bolus fentanyl overdose on components of the cardiopulmonary system up to one week post. SKH1 mice were administered subcutaneous fentanyl at the highest non-lethal dose (62 mg/kg), LD10 (110 mg/kg), or LD50 (135 mg/kg), before euthanasia at 40 min, 6 h, 24 h, or 7 d post-exposure. The cerebral cortex, heart, lungs, and plasma were assayed using an immune monitoring 48-plex panel. The results showed significantly dysregulated cytokine, chemokine, and growth factor concentrations compared to time-matched controls, principally in hearts, then lungs and plasma to a lesser extent, for the length of the study, with the cortex largely unaffected. Major significant analytes contributing to variance included eotaxin-1, IL-33, and betacellulin, which were generally downregulated across time. The results of this study suggest that cardiopulmonary toxicity may persist from a single fentanyl overdose and have wide implications for the endurance of the expanding population of survivors. [ABSTRACT FROM AUTHOR]

Fentanyl exposure and overdose are growing concerns in public health and occupational safety. This study aimed to establish parameters of fentanyl lethality in SKH1 mice for future overdose research. Lethality was determined using the up‐down procedure, with subjects monitored post‐administration using pulse oximetry (5 min) and then whole‐body plethysmography (40 min). Following the determination of subcutaneous dose–response, [18F]Fluorodeoxyglucose positron emission tomography (18F‐FDG PET) was performed after LD10 fentanyl at 40 min, 6 h, 24 h or 7 days post‐dose. LD10 and LD50 were observed to be 110 and 135 mg/kg, respectively, and consistent with four‐parameter logistic fit values of 111.2 and 134.6 mg/kg (r2 = 0.9996). Overdose (LD10 or greater) yielded three distinct cardiovascular groups: survival, non‐survival with blood oxygen saturation (SpO2) minimum ≥37% and non‐survival with SpO2 <37%. Breaths per minute, minute volume and inspiratory quotient were significantly different between surviving and non‐surviving animals for up to 40 min post‐injection. 18F‐FDG PET revealed decreased glucose uptake in the heart, lungs and brain for up to 24 h. These findings provide critical insights into fentanyl lethality in SKH1 mice, including non‐invasive respiratory effects and organ‐specific impacts that are invaluable for future translational studies investigating the temporal effects of fentanyl overdose. Fentanyl exposure and overdose are growing concerns in public health and occupational safety. This study aimed to establish parameters of fentanyl lethality in SKH1 mice for future overdose research. After a single subcutaneous injection of fentanyl, subjects were monitored via pulse oximetry for 5 min, respiration for 40 min, then imaged for glucose uptake using positron emission tomography (PET). Pulse oximetry revealed a cardiac phenomenon determining acute lethality, respiratory data exhibited significant differences associated with survival, and PET showed decreased glucose uptake for up to 24 h. These non‐invasive, organ‐specific findings are critical for future temporal studies on fentanyl overdose. [ABSTRACT FROM AUTHOR]

This essay reviews the Geographical section of the "International Handbook of Jewish Education" published in 2011. The differences between countries, their unique histories and cultures, are important, but their similarities are arguably more revealing. Indeed, on occasions when similar phenomena are examined in different places by different authors, the comparisons have the potential to shine new light on the challenges individuals see in their local contexts, and to deepen their understanding and insights about how to address them. In this article, the author attempts to identify those patterns, first, in terms of the common issues of Jewish educational practice, and second, in search of a common underlying or foundational challenge that permeates all Jewish space. Finally, the author includes a few remarks on Jewish space itself, and explores how a more nuanced understanding of it might inform educational thought and practice. (Contains 1 figure, 11 footnotes and 1 table.)