Cyclic oxygen exchange capacity of Ce-doped V2O5 materials for syngas production via high-temperature thermochemical-looping reforming of methane

Synthesis gas production via solar thermochemical reduction-oxidation reactions is a promising pathway towards sustainable carbon-neutral fuels. The redox capability of oxygen carriers with considerable thermal and chemical stability is highly desirable. In this study, we report Ce-doped V₂O₅ structures for high-temperature thermochemical-looping reforming of methane coupled to H₂O and CO₂ splitting reactions. Incorporation of fractional amounts of large cerium cations induces a V⁵⁺ to V³⁺ transition and partially forms a segregated CeVO₄ phase. More importantly, the effective combination of efficient ion mobility of cerium and high oxygen exchange capacity of vanadia achieves synergic and cyclable redox performance during the thermochemical reactions, whereas the pure vanadia powders undergo melting and show non-cyclic redox behaviour. These materials achieve noteworthy syngas production rates of up to 500 mmol mol_V⁻¹ min⁻¹ during the long-term stability test of 100 CO₂ splitting cycles. Interestingly, the cerium ions are mobile between the lattice and the surface of the Ce-doped vanadia powders during the repeated reduction and oxidation reactions and contribute towards the cyclic syngas production. However, this also causes the formation of the CeVO₄ phase in Ce-rich powders, which increases the H₂/CO ratios and lowers fuel selectivity, which can be controlled by optimizing the cerium concentration. These findings are noteworthy towards the experimental approach of evaluating the oxygen carriers with the help of advanced characterization techniques.

Cerium doping into the V₂O₅ lattice forms a reversible V₂O₃/VO redox pair after sequential methane partial oxidation and CO₂/H₂O splitting reactions and produces syngas (H₂, CO) with fast rates and high oxygen exchange capacity.

Circulating and Endometrial Regulatory T Cell and Related Populations in Endometriosis and Infertility: Endometriosis Is Associated with Blunting of Endometrial Cyclical Effects and Reduced Proportions in Moderate-Severe Disease

Evidence to date supports regulatory T cell (Treg) alterations in endometriosis; however, the relationship remains unclear, and Tregs have not previously been investigated with respect to infertility in endometriosis. This prospective cross-sectional cohort study details circulating and endometrial tissue-specific disturbances in Tregs and broader gated populations in women of reproductive age with and without endometriosis (n = 57 and 29, respectively) using flow cytometry and immunohistochemistry. Participants were characterised by menstrual cycle phase, r-ASRM endometriosis disease stage and fertility status.In the endometrium of women with endometriosis, endometrial Tregs and CD4+ lymphocyte proportions did not change between the proliferative and secretory phases, while in women without the disease, they significantly decreased (p = 0.045 and p = 0.039, respectively). In women with endometriosis, endometrial Tregs were lower than in women without endometriosis overall (p = 0.050 as a proportion of all CD45+ immune cells). We have shown for the first time that proportions of CD4+ lymphocytes (p = 0.021), overall lymphocytes (p = 0.034) and non-granulocytes (p = 0.027) were significantly decreased in the endometrium of women with moderate-severe (r-ASRM stages III and IV) compared to minimal-mild (r-ASRM stages I and II) endometriosis. During the secretory phase, circulating Treg proportions were significantly increased in infertile compared to fertile women (p = 0.049). This study confirms differences in endometrial Tregs in women with endometriosis, with blunting of normal menstrual cyclical variations, reduced proportions during the proliferative phase and disease stage-specific relationships.

55 Donor age has the least influence on recovery, quality, and in vitro developmental competence of ovum pickup–based Holstein Friesian oocytes under subtropical conditions

The use of oocytes obtained from younger donors for invitro fertilization followed by embryo transfer represents an opportunity to accelerate genetic gain by reducing generation interval. The present study was designed to evaluate the effect of age of donor on the follicular population, recovery, quality and invitro developmental competence of ovum pickup based Holstein Friesian oocytes under subtropical conditions. A total of eight (n=8) Holstein Friesian (with proper oestrus cyclicity) were selected for the study and divided into 2 groups based on animal age: (1) heifers (n=4), 1.5 to 2 years of age, and (2) adults (n=4), 5 to 6 years of age. The study was conducted near Lahore (31°33′ N, 74°19′ E), Punjab, Pakistan, from November 2019 to February 2020. The animals were wave synchronized using the physiological method of wave synchronization. After 4 days of second dominant follicle puncture, the first ovum pickup was carried out and a total of nine (n=9) OPU sessions were held for each group. The COCs from the follicles were aspirated using a transvaginal ultrasound–guided needle. Following searching and grading, COCs of grade A, B and C were processed for IVM in 100-µL droplets of BO-IVM under mineral oil at 37°C, 5% CO2, and 95% humidity for 24h. The frozen semen of a high-pedigree bull was thawed at 37°C and observed for post-thaw sperm motility. The semen samples of the same bull having motility >50% were processed using the sperm swim-up method throughout the study. The IVF was carried out by placing the COCs and required amount of sperm in 100-µL droplets of BO-IVF at similar conditions for a maximum of 18h. The presumptive zygotes were denuded by gentle pipetting and cultured for a period of 7 days after placing in 100-µL drops of BO-IVC at 37°C, 5% CO2, 5% O2, and maximum humidity. The presumptive zygotes were observed for cleavage rate and blastocyst rate on Days 2 and 7 following COCs-sperm co-incubation. Data on the follicular population, oocytes recovered, and viable oocytes were analysed by the PROC GLIMMIX of SAS (SAS Institute Inc.), and proportional data were analysed by the Chi-squared method using SAS 9.1. COCs of grade AB (35.2 vs. 25.4%) were higher (P>0.05) in the adult group than in the heifer group, respectively. Similarly, COCs with grade CD (57.5 vs. 71.9%) were lower (P<0.05) in the adult group compared with the heifer group, respectively. However, the total follicles (6.55±0.42 vs. 6.39±0.39), number of COCs recovered (3.33±0.32 vs. 3.17±0.41), viable oocytes (3.08±0.29 vs. 3.08±0.39), cleavage rate (60.3 vs. 68.7%), and blastocyst rate (38.7 vs. 48.8%) did not differ (P>0.05) between the groups. To conclude, donor age up to third lactation, under subtropical conditions, does not affect invitro embryo production in Holstein Friesian undergoing repeated OPU.

54 Effect of clinical endometritis on the follicle growth dynamics, oocyte recovery, oocyte quality, and invitro developmental competence of oocytes using ovum pickup in Sahiwal cattle

Sahiwal cattle is the premium quality milk breed of cattle in Pakistan. Uterine infections often lead to culling of valuable animals from a herd, resulting in genetic drain. The genetic potential of problematic females could be reaped by invitro embryo production. The objective of the present study was to evaluate the effect of clinical endometritis on follicle growth dynamics, recovery, quality, and invitro developmental competence of oocytes using ovum pickup (OPU) in Sahiwal cattle. The animals, 5–7 years of age, third or fourth parity, and 160 to 170 days in milk (DIM), were inspected for any discharge at the vulva or inside the vagina. Then, B-mode ultrasonography was performed to measure the diameter of cervix and to examine the uterus for the presence of pus. The animals (n=12) were divided into 2 groups: (1) healthy (n=6), and (2) clinical endometritis (n=6), based on the presence or absence of pus at the vulva or in the vagina. The first OPU was performed after 7 days of dominant follicle puncture and subsequently repeated OPUs (54 and 50), after every 7 days over 9 OPU sessions, were performed in the healthy group and clinical endometritis group, respectively. Follicles were aspirated using transvaginal ultrasound–guided needle. Viable COCs were considered for further processing only and were placed in the 100-µL droplets of BO-IVM medium and incubated at 37°C, 5% CO2, and 95% humidity for 24h. Nuclear maturation was estimated by staining the oocytes with Hoechst 33342. Frozen semen from the same Sahiwal bull was thawed and processed for IVF throughout the study. Sperm were prepared using swim-up protocol. Sperm and COCs were co-incubated in 100-µL droplets of BO-IVF for 18h. Finally, presumptive zygotes were cultured in 100-µL drops of BO-IVC medium at 37°C, 5% CO2, 5% O2, and 95% humidity for a period of 7 days. Cleavage rate and blastocyst rate were recorded on Day 2 and 7 following IVF, respectively. The data were analysed using the GLIMMIX procedure of SAS (SAS Institute Inc.). The results revealed that the number of medium-sized follicle (1.32±0.11 vs. 0.56±0.11) and total follicles (9.14±0.70 vs. 6.58±0.72) were higher (P<0.05) in the healthy group than in the clinical endometritis group, respectively. Similarly, the number of oocytes recovered (5.05±0.39 vs. 2.78±0.41), viable oocytes (2.87±0.25 vs. 1.46±0.26), COCs with grade AB, having minimum of 2 cumulus cell layers and homogeneous cytoplasm, (33 vs. 20%) and nuclear maturation (68 vs. 55%) were also higher (P<0.05) in the healthy group than in the clinical endometritis group, respectively. However, cleavage rate (55 vs. 46%) and blastocyst rate (29 vs. 26%) did not differ (P>0.05) between the groups. In conclusion, clinical endometritis has a negative effect on follicle growth dynamics, oocyte recovery, oocyte quality, and nuclear maturation; however, the developmental competence of COCs is not compromised by it.

International Nosocomial Infection Control Consortium (INICC) report, data summary of 45 countries for 2012-2017: Device-associated module

BACKGROUND

We report the results of International Nosocomial Infection Control Consortium (INICC) surveillance study from January 2012 to December 2017 in 523 intensive care units (ICUs) in 45 countries from Latin America, Europe, Eastern Mediterranean, Southeast Asia, and Western Pacific.

METHODS

During the 6-year study period, prospective data from 532,483 ICU patients hospitalized in 242 hospitals, for an aggregate of 2,197,304 patient days, were collected through the INICC Surveillance Online System (ISOS). The Centers for Disease Control and Prevention-National Healthcare Safety Network (CDC-NHSN) definitions for device-associated health care-associated infection (DA-HAI) were applied.

RESULTS

Although device use in INICC ICUs was similar to that reported from CDC-NHSN ICUs, DA-HAI rates were higher in the INICC ICUs: in the medical-surgical ICUs, the pooled central line-associated bloodstream infection rate was higher (5.05 vs 0.8 per 1,000 central line-days); the ventilator-associated pneumonia rate was also higher (14.1 vs 0.9 per 1,000 ventilator-days,), as well as the rate of catheter-associated urinary tract infection (5.1 vs 1.7 per 1,000 catheter-days). From blood cultures samples, frequencies of resistance, such as of Pseudomonas aeruginosa to piperacillin-tazobactam (33.0% vs 18.3%), were also higher.

CONCLUSIONS

Despite a significant trend toward the reduction in INICC ICUs, DA-HAI rates are still much higher compared with CDC-NHSN's ICUs representing the developed world. It is INICC's main goal to provide basic and cost-effective resources, through the INICC Surveillance Online System to tackle the burden of DA-HAIs effectively.

Concentration-Dependent Solar Thermochemical CO2/H2O Splitting Performance by Vanadia-Ceria Multiphase Metal Oxide Systems

The effects of V and Ce concentrations (each varying in the 0–100% range) in vanadia–ceria multiphase systems are investigated for synthesis gas production via thermochemical redox cycles of CO₂ and H₂O splitting coupled to methane partial oxidation reactions. The oxidation of prepared oxygen carriers is performed by separate and sequential CO₂ and H₂O splitting reactions. Structural and chemical analyses of the mixed-metal oxides revealed important information about the Ce and V interactions affecting their crystal phases and redox characteristics. Pure CeO₂ and pure V₂O₅ are found to offer the lowest and highest oxygen exchange capacities and syngas production performance, respectively. The mixed-oxide systems provide a balanced performance: their oxygen exchange capacity is up to 5 times higher than that of pure CeO₂ while decreasing the extent of methane cracking. The addition of 25% V to CeO₂ results in an optimum mixture of CeO₂ and CeVO₄ for enhanced CO₂ and H₂O splitting. At higher V concentrations, cyclic carbide formation and oxidation result in a syngas yield higher than that for pure CeO₂.

193 Effect of clinical metritis on oocyte recovery, oocyte quality, and early invitro developmental competence of embryos in Bos indicus dairy cattle

Unhygienic practices at the time of parturition or AI lead to uterine infections. The uterine infections ultimately result in genetic drain by culling the elite animals. The invivo developmental competence of embryos is compromised in clinically metritic animals. The genetic potential of problematic females could be harvested by invitro embryo production (IVEP). Therefore, the objective of the present study was to evaluate the effect of clinical metritis on oocyte recovery, oocyte quality, and early invitro developmental competence of embryos in Bos indicus dairy cattle. This experiment was carried out from December 2017 to April 2018. Ovaries were collected from a local abattoir (Bos indicus; 5- to 8-year-old dairy cattle, body condition score 2.75±0.25, mixed parity). These ovaries (n=982) were divided into two groups: (1) clinically metritic (n=184), and (2) healthy (n=798), based upon the presence or absence of pus in the uterine lumen. Oocytes were aspirated from follicles using an 18G needle attached to a 10-mL syringe. Cumulus-oocyte complexes (COCs) were categorized into A, B, C, and D grades based on the number of layers of cumulus cells and integrity of ooplasm. The oocytes of grades A and B were subsequently transferred in groups (10/group) in four-well plates containing 100-μL droplets. The droplets with oocytes were covered with prewarmed mineral oil and incubated for 24h at 38.5°C, 5% CO2, and 95% relative humidity. The oocytes were evaluated for IVM on the basis of cumulus expansion. Frozen semen was thawed and prepared using the sperm swim-up procedure for each group. Spermatozoa and oocytes were incubated together for a period of 18h. The presumptive zygotes were invitro cultured for 4 days in a CO2 incubator under similar culture conditions. The cleavage rate, 4-cell, and 8-cell stages were recorded on Days 2, 3, and 4 after the day of insemination, respectively. Data on oocyte recovery, oocyte quality, IVM, cleavage rate, and 4-cell and 8-cell stages were analysed by Chi-squared test using SPSS software (version 20; IBM Corp.) for Windows. Results demonstrated that recovery rate was lower (63.8% vs. 71.7%; P<0.05) in clinically metritic compared with healthy cattle. Similarly, oocytes of grade A and B quality were lower (41.0% vs. 51.1%; P<0.05), whereas those of C and D quality were higher (59.0% vs. 48.9%; P<0.05) in clinically metritic compared with the healthy group. Moreover, 4-cell (38.2% vs. 54.8%) and 8-cell stage embryos (11.3% vs. 29.1%), were lower (P<0.05) in the clinically metritic compared with the healthy group, respectively. However, maturation rate and cleavage rate did not differ (P>0.05) between groups. In conclusion, metritis in slaughterhouse ovaries negatively affects oocyte recovery rate, oocyte quality, and early invitro developmental competence of embryos in Bos indicus dairy cattle.

Fractionation of Lignocellulosic Biomass over Core-Shell Ni@Al2 O3 Catalysts with Formic Acid as a Cocatalyst and Hydrogen Source

Highly dispersed, core-shell Ni@Al₂ O₃ on activated carbon (AC) catalysts were prepared to develop an effective, external-hydrogen-free fractionation process for various types of lignocellulosic biomass. In a mixture of formic acid, ethanol, and water at 190 °C, the conversion of oak wood produced 23.4 C% lignin-derived phenolic monomers (LDPMs) and highly delignified pulp-rich solid. At an early stage, formic acid acted as a cocatalyst to enhance the delignification by solvolysis, and at a later stage, it acted as a hydrogen source to stabilize the phenolic monomers by hydrodeoxygenation and hydrogenation. Based on the positive correlation between spillover hydrogen on the catalysts and LDPM yields, a new suite of catalyst design criteria was proposed to develop highly active, non-noble-metal based catalysts for realizing economically viable biorefineries. Enzymatic saccharification of the pulp-rich solid indicated that the pulp-rich solid is an excellent source of fermentable sugars.