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Access status: Open Access ,
High-throughput sperm DNA analysis at the single-cell and population levels
(Royal Society of Chemistry, 2023-07-13) Simchi, Mohammad; Riordon, Jason; Wang, Yihe; McCallum, Christopher; You, Jae Bem; Jarvi, Keith; Nosrati, Reza; Sinton, David
Clinical semen quality assessment is critical to the treatment of infertility. Sperm DNA integrity testing provides critical information that can steer treatment and influence outcomes and offspring health. Flow cytometry is the gold standard approach to assess DNA integrity, but it is not commonly applied at the clinical level. The sperm chromatin dispersion (SCD) assay provides a simpler and cheaper alternative. However, SCD is low-throughput and non-quantitative – sperm assessment is serial, manual and suffers inter- and intra-observer variations. Here, an automated SCD analysis method is presented that enables quantitative sperm DNA quality assessment at the single-cell and population levels. Levering automated optical microscopy and a chromatin diffusion-based analysis, a sample of thousands of sperm that would otherwise require 5 hours is assessed in under 10 minutes – a clinically viable workflow. The sperm DNA diffusion coefficient (DDNA) measurement correlates (R2 = 0.96) with DNA fragmentation index (DFI) from the cytometry-based sperm chromatin structure assay (SCSA). The automated measurement of population-level sperm DNA fragmentation (% sDF) prevents inter-observer variations and shows a good agreement with the SCSA % DFI (R2 = 0.98). This automated approach standardizes and accelerates SCD-based sperm DNA analysis, enabling the clinical application of sperm DNA integrity assessment.
Access status: Open Access ,
Cationic-group-functionalized electrocatalysts enable stable acidic CO2 electrolysis
(Springer Nature, 2023-08-21) Fan, Mengyang; Huang, Jianan Erick; Miao, Rui Kai; Mao, Yu; Ou, Pengfei; Li, Feng; Li, Xiao-Yan; Cao, Yufei; Zhang, Zishuai; Zhang, Jinqiang; Yan, Yu; Ozden, Adnan; Ni, Weiyan; Wang, Ying; Zhao, Yong; Chen, Zhu; Khatir, Behrooz; O’Brien, Colin P.; Xu, Yi; Xiao, Yurou Celine; Waterhouse, Geoffrey I. N.; Golovin, Kevin; Wang, Ziyun; Sargent, Edward H.; Sinton, David
Acidic electrochemical CO2 reduction (CO2R) addresses CO2 loss and thus mitigates the energy penalties associated with CO2 recovery; however, acidic CO2R suffers low selectivity. One promising remedy—using a high concentration of alkali cations—steers CO2R towards multi-carbon (C2+) products, but these same alkali cations result in salt formation, limiting operating stability to <15 h. Here we present a copper catalyst functionalized with cationic groups (CG) that enables efficient CO2 activation in a stable manner. By replacing alkali cations with immobilized benzimidazolium CG within ionomer coatings, we achieve over 150 h of stable CO2R in acid. We find the water-management property of CG minimizes proton migration that enables operation at a modest voltage of 3.3 V with mildly alkaline local pH, leading to more energy-efficient CO2R with a C2+ Faradaic efficiency of 80 ± 3%. As a result, we report an energy efficiency of 28% for acidic CO2R towards C2+ products and a single-pass CO2 conversion efficiency exceeding 70%.
Access status: Open Access ,
Pickering phase change slurries
(Elsevier, 2023-07-29) Saber, Sepehr; Zargartalebi, Mohammad; Kazemi, Amin; Sinton, David
Hypothesis Phase change slurries (PCS) have emerged as a promising class of oil-in-water emulsions for energy applications, but stability remains an issue. Pickering phase change slurries (PPCS) stabilized solely by nanoparticles could offer enhanced stability. We hypothesize that stability in PPCS can be achieved by tuning environmental variables of salinity and temperature. Experiments A paraffin-based PPCS stabilized using fumed silica nanoparticles was developed and assessed under varying NaCl concentrations (up to 150 mM) and temperatures (up to 70 °C). Extended-DLVO modeling, confocal, and cryogenic electron microscopy analyzed the silica-paraffin interactions. Rheological experiments examined the impact of effective volume fraction, thermal expansion, and salinity on the viscosity and shear stability of PPCS. The stability of the resulting formulation was assessed under high pressure and temperature conditions. Findings Increased salinity did not change the packing density of the silica at the oil–water interface (82% ± 6%) but did increase the adsorbed layer thickness and network formation, enhancing the formulation's resistance to shear-induced instability. A critical volume fraction of 0.51 ± 0.01 was identified, beyond which viscosity increased significantly. The resulting formulations remained stable under high pressures and temperatures, regardless of salinity. These findings offer insights into the variables affecting PPCS properties, assisting in designing stable PPCS formulations for diverse applications.
Access status: Open Access ,
Electrified Cement Production via Anion-Mediated Electrochemical Calcium Extraction
(American Chemical Society, 2023-10-16) Miao, Rui Kai; Wang, Ning; Hung, Sung-Fu; Huang, Wen-Yang; Zhang, Jinqiang; Zhao, Yong; Ou, Pengfei; Wang, Sasa; Edwards, Jonathan P.; Tian, Cong; Han, Jingrui; Xu, Yi; Fan, Mengyang; Huang, Jianan Erick; Xiao, Yurou Celine; Ip, Alexander H.; Liang, Hongyan; Sargent, Edward H.; Sinton, David
Cement production is a carbon-intensive industrial process, with the sector contributing ∼8% of global anthropogenic CO2 emissions. On average, producing each kilogram of cement leads to the emission of 1 kg of CO2─the combination of fuel combustion emissions and carbon released from the feedstock, limestone (CaCO3). Here we report electrochemical cement production based on anion-mediated electrochemical calcium extraction (ECE) that addresses both feedstock and energy emissions. The in situ-generated acidic electrolytes release the feedstock CO2 emissions at high purity, enabling direct carbon utilization or sequestration without costly capture and purification steps. Energy embodied within a separate H2 output stream is sufficient to sinter Ca(OH)2 to produce portland cement, thus removing the CO2 emissions associated with fuel combustion. We then replace CaCO3 with a carbon-free calcium feedstock, gypsum, thereby removing the CO2 emissions embodied in the feedstock. Technoeconomic analysis forecasts that this method could provide a viable, decarbonized cement alternative.
Access status: Open Access ,
Developmental trajectories predictive of stillbirth in a longitudinal mouse model of fetal growth restriction
(American Physiological Society, 2025-11-03) Smolina, Anastasia; Rahman, Anum; Cahill, Lindsay; Macgowan, Christopher K.; Seed, Mike; Kingdom, John; Sled, John G.
Fetal growth restriction (FGR) secondary to placental insufﬁciency often leads to morbidity and mortality in the perinatal period.Fetal adaptations such as “brain sparing” blood ﬂow redistribution offer some protection, but predicting whether a fetus in thisstate will survive is challenging. The goal of this research was to identify vascular responses predictive of stillbirth or hypoxia based on serial Doppler ultrasound measurement in a mouse model of FGR. We performed serial Doppler ultrasound observations of fetal blood ﬂow redistribution in a murine model of FGR, where prolongation of pregnancy was induced pharmacologically with progesterone in 56 CD-1 mice. Observations were made at E18.5 (physiologic term), E19.5 (term þ 1), and E20.5 (termþ 2). Flow velocity waveforms were obtained from the middle cerebral artery (MCA), ductus arteriosus (DA), main pulmonary artery (MPA), ductus venosus (DV), umbilical artery (UA), and umbilical vein (UV). Following euthanasia, pimonidazole immunohistochemistry quantiﬁed tissue hypoxia. Among 56 pregnancies, the strongest predictor of stillbirth was low DA peak systolic velocity at E19.5 (<217 mm/s, p=0.021, R2=0.52). Among survivors, cerebral hypoxia was predicted by elevated MCA peak systolic (>26.6 mm/s, p=0.022, R2=0.59) and end-diastolic velocity (>10.1 mm/s, p=0.043, R2=0.53, whereas high MPA ﬂow (>0.73 mL/min, p=0.029, R2=0.51) predicted hepatic hypoxia. Overall, fetuses with a weaker pulmonary blood ﬂow redistribution response were found to have worse outcomes, despite cerebral vasodilation. This minimally invasive murine model offers valuable insights into this pathophysiology of FGR-related stillbirth and highlights the prognostic potential of assessing fetal brain ﬂow and pulmonary perfusion in tandem during sonographic surveillance of high-risk pregnancies.