Highly acid-durable carbon coated Co3O4 nanoarrays as efficient oxygen evolution electrocatalysts

Most oxygen evolution reaction (OER) electrocatalysts are not stable in corrosive acids. Even the expensive RuO2 or IrO2, the most acid-resistant oxides, can be dissolved at an oxidative potential. Herein, we realize that the failures of OER catalysts are mostly caused by the weak interface between catalysts and the substrates. Hence, the study of the interface structure between catalysts and substrates is critical. In this work, we observe that the cheap OER catalysts Co3O4 can be more durable than the state-of-the-art RuO2 if the interface quality is good enough. The Co3O4 nanosheets deposited on carbon paper (Co3O4/CP) is prepared by electroplating of Co-species and followed by a two-step calcination process. The 1st step occurs in vacuum in order to maintain the surface integrity of the carbon paper and converts Co-species to Co(II)O. The 2nd step is a calcination in ambient conditions which enables the complete transformation of Co(II)O to Co3O4 without degrading the mechanical strength of the Co3O4-CP interface. Equally important, an in situ formation of a layer of amorphous carbon on top of Co3O4 further enhances the OER catalyst stability. Therefore, these key advances make the Co3O4 catalyst highly active toward the OER in 0.5 M H2SO4 with a small overpotential (370 mV), to reach 10 mA/cm2. The observed long lifetime for 86.8 h at a constant current density of 100 mA/cm2, is among the best of the reported in literature so far, even longer than the state-of-art RuO2 on CP. Overall, our study provides a new insight and methodology for the construction of a high-performance and high stability OER electrocatalysts in corrosive acidic environments

Predictors of institutional delivery service utilization among women of reproductive age in Senegal: a population-based study

Background: In Senegal, sub-Saharan Africa, many women continue to die from pregnancy and childbirth complications. Even though health facility delivery is a key intervention to reducing maternal death, utilization is low. There is a dearth of evidence on determinants of health facility delivery in Senegal. Therefore, this study investigated the predictors of health facility-based delivery utilization in Senegal. Methods: Data from the 2017 Senegal Continuous Survey were extracted for this study, and approximately 11,487 ever-married women aged 15–49 years participated. Chi-square test was used to select significant variables and multivariable logistic regression analysis was performed to identify statistically significant predictors at a 95% confidence interval with a 0.05 p-value using Stata version 14 software. Results: Facility-based delivery utilization was 77.7% and the main predictors were maternal educational status (primary school Adjusted Odds Ratio [aOR] = 1.44, 95% CI; 1.14–1.83; secondary school aOR = 1.62, 95% CI; 1.17– 2.25), husband’s educational status (primary school aOR = 1.65, 95% CI; 1.24–2.20, secondary school aOR = 2.17, 95% CI; 1.52–3.10), maternal occupation (agricultural-self-employed aOR = 0.77, 95% CI; 0.62–0.96), ethnicity (Poular aOR = 0.74, 95% CI; 0.56–0.97), place of residence (rural aOR = 0.57, 95% CI; 0.43, 0.74), media exposure (yes aOR = 1.26, 95% CI; 1.02–1.57), economic status (richest aOR = 5.27, 95% CI; 2.85–9.73), parity (seven and above aOR =0.46, 95% CI; 0.34–0.62), wife beating attitude (refuse aOR =1.23, 95% CI; 1.05–1.44) and skilled antenatal care (ANC) (yes aOR = 4.34, 95% CI; 3.10–6.08). Conclusion: Uptake of health facility delivery services was seen among women who were educated, exposed to media, wealthy, against wife-beating, attended ANC by skilled attendants and had educated husbands. On the other hand, women from ethnic groups like Poular, those working in agricultural activities, living in rural setting, and those who had more delivery history were less likely to deliver at a health facility. Therefore, there is the need to empower women by encouraging them to use skilled ANC services in order for them to gain the requisite knowledge they need to enhance their utilization of health facility delivery, whiles at the same time, removing socio-economic barriers to access to health facility delivery that occur from low education, poverty and rural dwelling

Predictors of institutional delivery service utilization among women of reproductive age in Senegal: a population-based study

Background: In Senegal, sub-Saharan Africa, many women continue to die from pregnancy and childbirth complications. Even though health facility delivery is a key intervention to reducing maternal death, utilization is low. There is a dearth of evidence on determinants of health facility delivery in Senegal. Therefore, this study investigated the predictors of health facility-based delivery utilization in Senegal. Methods: Data from the 2017 Senegal Continuous Survey were extracted for this study, and approximately 11,487 ever-married women aged 15–49 years participated. Chi-square test was used to select significant variables and multivariable logistic regression analysis was performed to identify statistically significant predictors at a 95% confidence interval with a 0.05 p-value using Stata version 14 software. Results: Facility-based delivery utilization was 77.7% and the main predictors were maternal educational status (primary school Adjusted Odds Ratio [aOR] = 1.44, 95% CI; 1.14–1.83; secondary school aOR = 1.62, 95% CI; 1.17– 2.25), husband’s educational status (primary school aOR = 1.65, 95% CI; 1.24–2.20, secondary school aOR = 2.17, 95% CI; 1.52–3.10), maternal occupation (agricultural-self-employed aOR = 0.77, 95% CI; 0.62–0.96), ethnicity (Poular aOR = 0.74, 95% CI; 0.56–0.97), place of residence (rural aOR = 0.57, 95% CI; 0.43, 0.74), media exposure (yes aOR = 1.26, 95% CI; 1.02–1.57), economic status (richest aOR = 5.27, 95% CI; 2.85–9.73), parity (seven and above aOR =0.46, 95% CI; 0.34–0.62), wife beating attitude (refuse aOR =1.23, 95% CI; 1.05–1.44) and skilled antenatal care (ANC) (yes aOR = 4.34, 95% CI; 3.10–6.08). Conclusion: Uptake of health facility delivery services was seen among women who were educated, exposed to media, wealthy, against wife-beating, attended ANC by skilled attendants and had educated husbands. On the other hand, women from ethnic groups like Poular, those working in agricultural activities, living in rural setting, and those who had more delivery history were less likely to deliver at a health facility. Therefore, there is the need to empower women by encouraging them to use skilled ANC services in order for them to gain the requisite knowledge they need to enhance their utilization of health facility delivery, whiles at the same time, removing socio-economic barriers to access to health facility delivery that occur from low education, poverty and rural dwelling

Unravelling Site-Specific Photo-Reactions of Ethanol on Rutile TiO2(110)

Finding the active sites of catalysts and photo-catalysts is crucial for an improved fundamental understanding and the development of efficient catalytic systems. Here we have studied the photo-activated dehydrogenation of ethanol on reduced and oxidized rutile TiO2(110) in ultrahigh vacuum conditions. Utilizing scanning tunnelling microscopy, various spectroscopic techniques and theoretical calculations we found that the photo-reaction proceeds most efficiently when the reactants are adsorbed on regular Ti surface sites, whereas species that are strongly adsorbed at surface defects such as O vacancies and step edges show little reaction under reducing conditions. We propose that regular Ti surface sites are the most active sites in photo-reactions on TiO2

The prevalence, antibiotic resistance and mecA characterization of coagulase negative staphylococci recovered from non-healthcare settings in London, UK

Background Coagulase negative staphylococci (CoNS) are important reservoirs of antibiotic resistance genes and associated mobile genetic elements and are believed to contribute to the emergence of successful methicillin resistant Staphylococcus aureus (MRSA) clones. Although, these bacteria have been linked to various ecological niches, little is known about the dissemination and genetic diversity of antibiotic resistant CoNS in general public settings. Methods Four hundred seventy-nine samples were collected from different non-healthcare/general public settings in various locations (n = 355) and from the hands of volunteers (n = 124) in London UK between April 2013 and Nov 2014. Results Six hundred forty-three staphylococcal isolates belonging to 19 staphylococcal species were identified. Five hundred seventy-two (94%) isolates were resistant to at least one antibiotic, and only 34 isolates were fully susceptible. Sixty-eight (11%) mecA positive staphylococcal isolates were determined in this study. SCCmec types were fully determined for forty-six isolates. Thirteen staphylococci (19%) carried SCCmec V, followed by 8 isolates carrying SCCmec type I (2%), 5 SCCmec type IV (7%), 4 SCCmec type II (6%), 1 SCCmec type III (2%), 1 SCCmec type VI (2%), and 1 SCCmec type VIII (2%). In addition, three isolates harboured a new SCCmec type 1A, which carried combination of class A mec complex and ccr type 1. MLST typing revealed that all S. epidermidis strains possess new MLST types and were assigned the following new sequence types: ST599, ST600, ST600, ST600, ST601, ST602, ST602, ST603, ST604, ST605, ST606, ST607 and ST608. Conclusions The prevalence of antibiotic resistant staphylococci in general public settings demonstrates that antibiotics in the natural environments contribute to the selection of antibiotic resistant microorganisms. The finding of various SCCmec types in non-healthcare associated environments indicates the complexity of SCCmec. We also report on new MLST types that were assigned for all S. epidermidis isolates, which demonstrates the genetic variability of these isolates

Back on track – On the role of the microtubule for kinesin motility and cellular function

The evolution of cytoskeletal filaments (actin- and intermediate-filaments, and the microtubules) and their associated motor- and non-motor-proteins has enabled the eukaryotic cell to achieve complex organizational and structural tasks. This ability to control cellular transport processes and structures allowed for the development of such complex cellular organelles like cilia or flagella in single-cell organisms and made possible the development and differentiation of multi-cellular organisms with highly specialized, polarized cells. Also, the faithful segregation of large amounts of genetic information during cell division relies crucially on the reorganization and control of the cytoskeleton, making the cytoskeleton a key prerequisite for the development of highly complex genomes. Therefore, it is not surprising that the eukaryotic cell continuously invests considerable resources in the establishment, maintenance, modification and rearrangement of the cytoskeletal filaments and the regulation of its interaction with accessory proteins. Here we review the literature on the interaction between microtubules and motor-proteins of the kinesin-family. Our particular interest is the role of the microtubule in the regulation of kinesin motility and cellular function. After an introduction of the kinesin–microtubule interaction we focus on two interrelated aspects: (1) the active allosteric participation of the microtubule during the interaction with kinesins in general and (2) the possible regulatory role of post-translational modifications of the microtubule in the kinesin–microtubule interaction.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/42588/1/10974_2005_Article_9052.pd