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2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a potent and environmentally persistent endocrine disrupting chemical. Our previous work demonstrated the latent reproductive maladies of early-life TCDD exposure in zebrafish. Zebrafish acutely exposed to low, environmentally relevant levels of TCDD (50 pg/mL) during two windows of sexual differentiation in development (1 hour of exposure at 3 and 7 weeks postfertilization) were later infertile, showed a reduction in sperm, and exhibited gene expression consistent with an altered microenvironment, even months after exposure. Due to the highly heterogeneous cell- type and -stage landscape of the testes, we hypothesized various cell types contribute markedly different profiles toward the pathology of TCDD exposure. To investigate the contributions of the diverse cell types in the adult zebrafish testes to TCDD-induced pathology, we utilized single-cell RNA-seq and the 10x Genomics platform. The method successfully captured every stage of testicular germ cell development. Testes of adult fish exposed during sexual differentiation to TCDD contained sharply decreased populations of late spermatocytes, spermatids, and spermatozoa. Spermatogonia and early spermatocyte populations were, in contrast, enriched following exposure. Pathway analysis of differentially expressed genes supported previous findings that TCDD exposure resulted in male infertility, and suggested this outcome is due to apoptosis of spermatids and spermatozoa, even years after exposure cessation. Increased germ cell apoptosis was confirmed histologically. These results provide support for an environmental exposure explanation of idiopathic male infertility.

In this report, we compare the outcomes and limitations of two methods of transcriptomic inquiry on adult zebrafish testes exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) during sexual differentiation: conventional or bulk RNA-seq (bulk-seq) and single cell RNA sequencing (scRNA-seq) data. scRNA-seq has emerged as a valuable tool for uncovering cell type-specific transcriptome dynamics which exist in heterogeneous tissue. Our lab previously showed the toxicological value of the scRNA-seq pipeline to characterize the sequelae of TCDD exposure in testes, demonstrating that loss of spermatids and spermatozoa, but not other cell types, contributed to the pathology of infertility in adult male zebrafish exposed during sexual differentiation. To investigate the potential for technical artifacts in scRNA-seq such as cell dissociation effects and reduced transcriptome coverage, we compared bulk-sequenced and scRNA-seq-paired samples from control and TCDD-exposed samples to understand what is gained and lost in scRNA-seq vs bulk-seq, both transcriptomically and toxicologically. We hypothesized that the testes may be sensitive to tissue disruption as they contain multiple cell types under constant division and/or maturation, and that TCDD exposure may mediate the extent of sensitivity. Thus, we sought to understand the extent to which this dissociation impacts the toxicological value of data returned from scRNA-seq. We confirm that the required dissociation of individual cells from intact tissue has a significant impact on gene expression, affecting gene pathways with the potential to confound toxicogenomics studies on exposures if findings are not well-controlled and well-situated in context. Additionally, a common scRNA-seq method using cDNA amplified from the 3’ end of mRNA under-detects low-expressing transcripts including transcription factors. We confirm this, and show TCDD-related genes may be overlooked by scRNA-seq, however, this under-detection effect is not mediated by TCDD exposure. Even so, scRNA-seq generally extracted toxicologically relevant information better than the bulk-seq method in the present study. This report aims to inform future experimental design for transcriptomic investigation in the growing field of toxicogenomics by demonstrating the differential information extracted from sequencing cells—despite being from the same tissue and exposure scheme—is influenced by the specific protocol used, with implications for the interpretation of exposure-induced risk.

Developability considerations should be integrated with lead engineering of antibody drug candidates in interest of their cost effective translations into medicines. To explore feasibility of this imperative, we have performed rational mutagenesis studies on a monoclonal antibody (MAB1) whose development was discontinued owing to manufacturability hurdles. Seven computationally designed variants of MAB1 containing single point (V44K, E59S, E59T and E59Y) and double (V44KE59S, V44KE59T and V44KE59Y) mutations in its light chain were produced in Chinese Hamster Ovary (CHO) cells and purified by using platform processes employed during commercial scale production of monoclonal antibodies. MAB1 and its variants were formulated in the same platform buffer and subjected to a battery of experiments to assess their solution behaviors, and biological activities. Five of the seven (71%) variants of MAB1 demonstrated improved biophysical attributes in multiple experimental testings. Contrary to the commonly expressed reservations about potential biological activity loss upon developability optimizations, the improvements in solution behavior of MAB1 also increased its biological activity up to ~180%. In particular, concentrate-ability and apparent solubility of V44KE59S improved to ~150% and ~160%, respectively. Its diffusion interaction parameter (kD) reduced to 28% and viscosity at ~100 mg/ml decreased to less than half of the corresponding values for MAB1. V44KE59S is also slightly more active and its transfections in CHO cells were more productive. It also degraded slower than MAB1 in three month long 25°C and 40°C formulation stability studies. These results open doors to an exciting realm of structure-based biologic drug design where developability and biological activity can be simultaneously optimized at the molecular engineering stages.

Background Clostridioides difficile infection and colonization are common in pediatric Crohn’s disease (CD). Our aims were to test the relationship between C. difficile positivity and bowel resection surgery and to characterize microbial shifts associated with C. difficile carriage and surgery. Methods A retrospective single-center study of 75 pediatric CD patients tested for association between C. difficile carriage and bowel resection surgery. A prospective single-center study of 70 CD patients utilized C. difficile testing and shotgun metagenomic sequencing of fecal samples to define microbiota variation stratified by C. difficile carriage or history of surgery. Results The rate of bowel resection surgery increased from 21% in those without C. difficile to 67% in those with (P = 0.003). From a Kaplan-Meier survival model, the hazard ratio for time to first surgery was 4.4 (95% CI, 1.2–16.2; P = 0.00) in patients with positive C. difficile testing in the first year after diagnosis. Multivariable logistic regression analysis confirmed this association (odds ratio 16.2; 95% CI, 2.2–120; P = 0.006). Larger differences in microbial abundance and metabolic pathways were observed in patients with prior surgery than in those with C. difficile carriage. Depletion of Alistipes and Ruminococcus species and reduction in methionine biosynthesis were noted in patients with both C. difficile carriage and past surgery. Conclusions A positive C. difficile test during the first year after diagnosis is associated with decreased time to first bowel resection surgery in pediatric Crohn’s disease. Depletion of beneficial commensals and methionine biosynthesis in patients with C. difficile carriage may contribute to increased risk for surgery.

The aviation industry has been one of the biggest beneficiaries of the major rise in electric power system technology for the past several decades. With more electric aircraft now the industry standard, the new future vision is toward all-electric aircraft, wherein conventional power systems and propulsion sources are electrified. This paper compares and analyzes the Electric Power Systems (EPS) of all-electric vehicles, all-electric ships and more electric aircraft to help predict future development of all-electric aircraft EPS. It is concluded that gravimetric energy density, weight, cost of current battery, and propulsion systems for aircraft are the main limitations preventing the transition to all-electric aircraft. Furthermore, lithium-air batteries show promise for closing the energy density gap between gasoline and batteries. Finally, some recent advancements in small-scale all-electric aircraft development illustrate the bright future of all-electric aircraft.

The penetration level of Plug-in Electric Vehicles (PEVs) is projected to rise in the future, which will lead to significant stress to the power grid due to frequent charging behaviors and their high power demand. While many studies have demonstrated the static stress caused by PEVs for specific scenarios, there is no software platform available for the visualization of the PEVs’ dynamic impacts at the distribution level of the power grid. This paper presents a software prototype that fills this gap. The prototype allows for easy parameter definition, including driving habits, and PEV types. Its back end allows fast integration and data processing for scattered PEV charging over wide areas. The prototype also considers mitigation efforts by providing built-in algorithms for coordinated charging and location planning of charging stations. The prototype is demonstrated on the IEEE 8500 node test case and power systems within Columbus, OH ranging from 81 to 1230 nodes.

More Electric Aircraft (MEA) promise many benefits (e.g., reduced weight, decreased fuel consumption, and high reliability), and their development continues to be the trend. Hybrid Unmanned Aerial Vehicles (UAVs) are an ideal prototype to implement concepts of electrification to aircraft due to their small size and the DC nature of their power systems. This paper proposes an energy optimization method to enhance the energy durability of a UAV. Compared to existing methods for hybrid electric platforms, e.g., ground electric vehicles and electric ships, the proposed method enhances accurate representation of load characteristics and high computation speed, which are critical for aerial vehicles. This is accomplished with a dynamic program containing an inner mixed-integer linear program and a detailed UAV simulation model containing physical circuitry characteristics, reflecting complex and nonlinear behavior within a real system. The efficacy of this method is validated on a realistic UAV system.

With increasing penetration and improving fast charging technologies, Plug-in Electric Vehicles (PEV) exert a disruptive influence on power delivery systems. The impulsive and high-power-density characteristics of PEV make conventional assessment methods of load impact unsuitable. This paper proposes an integrated method to investigate the long-term impact of PEV charging on temporal response and depreciation of grid assets in sub-transmission and distribution grid levels (below 69kV). Compared to conventional methods, the proposed method embeds dynamical system models of grid assets in Time-Series (TS) analysis and captures stochastic charging behavior through Monte-Carlo simulation, promising more robust and accurate assessment. Under the proposed method, the Total Cost of Ownership (TCO) of grid assets formulation is re-established. The results of this paper will enable utilities to quantify the capital and operation cost of grid assets induced under various PEV's penetration level and during any time span of interest.

Electric Vehicle (EV) sales continue to increase, making a preexisting need for updating current infrastructure even more important. Public charging, in particular, fast DC charging technologies can cause stress to the grid, including voltage deviations and increased loading, leading to issues including a degradation of power quality, power equipment loss of life, and brownouts. Literature has shown that distributed generation (DG) can serve as a solution to these stresses to the distribution grid. DG, however, have not been combined with EV charging stations as a method to offset to these stresses. The presented study quantifies the requirements of DG's location and output power in a distribution system with public EV charging stations. This pairing is particularly appealing as it increases generation capacity to meet the needs of EVs in a way which counters grid stress and increases the “green” nature of the grid, furthering the goal of lower emissions. The proposed benefits are demonstrated through three cases in the IEEE-37 bus system.

Counseling is a risky and rewarding business. While counseling invites mental health counselors to participate with their clients in the awesome process of human growth and healing, it also may threaten their well being through exposure to their clients' trauma and its painful consequences.The authors present a metaphor of a healthy tree to organize an overview of recent research regarding the risk and protective factors of vicarious traumatization of counselors. Implications for the practice, supervision, and management of counseling are presented.

Yin Yang 1 (YY1) is a multifunctional transcription factor that acts as an activator, repressor, or initiator of transcription of numerous cellular and viral genes. Previous studies in tissue culture model systems suggest YY1 plays a role in development and differentiation in multiple cell types, but the biological role of YY1 in vertebrate oocytes and embryos is not well understood. Here we analyzed expression, activity, and subcellular localization profiles of YY1 during Xenopus laevis development. Abundant levels of YY1 mRNA and protein were detected in early stage oocytes and in all subsequent stages of oocyte and embryonic development through to swimming larval stages. The DNA binding activity of YY1 was detected only in early oocytes (stages I and II) and in embryos after the midblastula transition (MBT), which suggested that its potential to modulate gene expression may be specifically repressed in the intervening period of development. Experiments to determine transcriptional activity showed that addition of YY1 recognition sites upstream of the thymidine kinase promoter had no stimulatory or repressive effect on basal transcription in oocytes and post-MBT embryos. Although the apparent transcriptional inactivity of YY1 in oocytes could be explained by the absence of DNA binding activity at this stage of development, the lack of transcriptional activity in post-MBT embryos was not expected given the ability of YY1 to bind its recognition elements. Subsequent Western blot and immunocytochemical analyses showed that YY1 is localized in the cytoplasm in oocytes and in cells of developing embryos well past the MBT. These findings suggest a novel mode of YY1 regulation during early development in which the potential transcriptional function of the maternally expressed factor is repressed by cytoplasmic localization.

It is time to retire the current Age Pension and give people the choice of continuing to work beyond 65 if they find value in doing so. A flexible pension age also has benefits for society as a whole. People who are physically fit and productive beyond the age of 65 increase the pool of available skills and may continue to pay taxes while they are employed. Continued employment might also have benefits in increasing the health of people in this group and thus reduce the cost of health care on the public purse.Failure to apply for a pension at the earliest possible date results in the loss of any entitlement to the forgone payments. This arrangement produces a strong incentive for eligible persons to cease employment immediately once pensionable age has been reached, thus introducing distortions into the country’s productive capacity. This paper examines the extent to which pensioners can be compensated for delaying access the Age Pension in Australia.