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Abstract Differentiation of cardiac progenitor cells (CPC) into cardiomyocytes is a fundamental step in cardiogenesis, which is marked by changes in gene expression responsible for remodeling of the cytoskeleton and in altering the mechanical properties of cells. Here we have induced the differentiation of CPC derived from human pluripotent stem cells into immature cardiomyocytes (iCM) which we compare with more differentiated cardiomyocytes (mCM). Using atomic force microscopy and real‐time deformability cytometry, we describe the mechanodynamic changes that occur during the differentiation process and link our findings to protein expression data of cytoskeletal proteins. Increased levels of cardiac‐specific markers as well as evolution of cytoskeletal morphology and contractility parameters correlated with the expected extent of cell differentiation that was accompanied by hypertrophic growth of cells. These changes were associated with switching in the balance of the different actin isoforms where β‐actin is predominantly found in CPC, smooth muscle α‐actin is dominant in iCM cells and sarcomeric α‐actin is found in significantly higher levels in mCM. We link these cytoskeletal changes to differences in mechano‐dynamic behavior of cells that translate to changes in Young's modulus that depend on the cell adherence. Our results demonstrate that the intracellular balance of actin isoform expression can be used as a sensitive ruler to determine the stage of differentiation during early phases of cardiomyocyte differentiation that correlates with an increased expression of sarcomeric proteins and is accompanied by changes in cellular elasticity.

Robotics is emerging as one of the most prominent research areas in the world and is recently attracting the Vietnamese research community. For the purpose of determining an entrance for a Vietnamese human interacting robotics system, this paper is aimed at proposing a service-oriented architecture for location assistance robotic systems made out of loosely-coupled and distributed web services. The proposed platform consists of two major components: a Speech Processing System (SPS) and a Service Manipulating System (SMS). This architecture allows our robot to meet three critical human interaction robotic systems requirements: flexibility, scalability and reliability. [ABSTRACT FROM AUTHOR]

The article discusses the cobalt catalyst for electrochemical water oxidation which has garnered attention due to its efficiency at neutral pH and self-assembly from low-cost materials. It notes that the catalyst assembles as an amorphous layer on inert cathodes by electrodeposition from an aqueous solution of cobalt and phosphate salts. It suggests that further studies are needed to address the functional relations in the biological and artificial water-oxidation catalysts.

The development and comprehensive understanding of nickel chalcogenides are critical since they constitute a class of efficient electro(pre)catalysts for the oxygen evolution reaction (OER) and value-added organic oxidations. This study introduces a knowledge-based facile approach to analogous NiE (E = S, Se, Te) phases, originating from molecular β-diketiminato [Ni 2 E 2 ] complexes and their application for OER and organic oxidations. The recorded activity trends for both target reactions follow the order NiSe > NiS > NiTe. Notably, NiSe displayed efficient performance for both OER and the selective oxidation of benzyl alcohol and 5-hydroxymethylfurfural, exhibiting stability in OER for 11 days under industrially pertinent conditions. Comprehensive analysis, including quasi in situ X-ray absorption and Raman spectroscopy, in combination with several ex situ techniques, revealed a material reconstruction process under alkaline OER conditions, involving chalcogen leaching. While NiS and NiSe experienced full chalcogen leaching and reconstruction into Ni III/IV oxyhydroxide active phases with intercalated potassium ions, the transformation of NiTe is incomplete. This study highlights the structure-activity relationship of a whole series of analogous nickel chalcogenides, directly linking material activity to the availability of active sites for catalysis. Such findings hold great promise for the development of efficient electrocatalysts for a wide range of applications, impacting various industrial processes and sustainable energy solutions.

In oxygen-evolving photosystem II (PSII), the multi-phasic electron transfer from a redox-active tyrosine residue (TyrZ) to a chlorophyll cation radical (P680 + ) precedes the water-oxidation chemistry of the S-state cycle of the Mn 4 Ca cluster. Here we investigate these early events, observable within about 10 ns to 10 ms after laser-flash excitation, by time-resolved single-frequency infrared (IR) spectroscopy in the spectral range of 1310-1890 cm -1 for oxygen-evolving PSII membrane particles from spinach. Comparing the IR difference spectra at 80 ns, 500 ns, and 10 µs allowed for the identification of quinone, P680 and TyrZ contributions. A broad electronic absorption band assignable P680 + was used to trace largely specifically the P680 + reduction kinetics. The experimental time resolution was taken into account in least-square fits of P680 + transients with a sum of four exponentials, revealing two nanosecond phases (30-46 ns and 690-1110 ns) and two microsecond phases (4.5-8.3 µs and 42 µs), which mostly exhibit a clear S-state dependence, in agreement with results obtained by other methods. Our investigation paves the road for further insight in the early events associated with TyrZ oxidation and their role in the preparing the PSII donor side for the subsequent water oxidation chemistry., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2023. The Author(s).)

The diiron(II) complex, [(OCO)Fe(MeCN)] 2 ( 1 , MeCN = acetonitrile), supported by the bis-phenolate carbene pincer ligand, 1,3-bis(3,5-di- tert -butyl-2-hydroxyphenyl)benzimidazolin-2-ylidene (OCO), was synthesized and characterized by single-crystal X-ray diffraction, 1 H nuclear magnetic resonance, infrared (IR) vibrational, ultraviolet/visible/near-infrared (UV/vis/NIR) electronic absorption, 57 Fe Mössbauer, X-band electron paramagnetic resonance (EPR) and SQUID magnetization measurements. Complex 1 activates dioxygen to yield the diferric, μ-oxo-bridged complex [(OCO)Fe(py)(μ-O)Fe(O(C═O)O)(py)] ( 2 ) that was isolated and fully characterized. In 2 , one of the iron-carbene bonds was oxidized to give a urea motif, resulting in an O(C NHC ═O)O binding site, while the other Fe(OCO) unit remained unchanged. When the reaction is performed at -80 °C, an intensively colored, purple intermediate is observed ( INT , λ max = 570 nm; ε = 5600 mol L -1 cm -1 ). INT acts as a sluggish oxidant, reacting only with easily oxidizable substrates, such as PPh 3 or 2-phenylpropionic aldehyde (2-PPA). The identity of INT can be best described as a dinuclear complex containing a closed diamond core motif [(OCO)Fe IV (μ-O) 2 Fe IV (OCO)]. This proposal is based on extensive spectroscopic [UV/vis/NIR electronic absorption, 57 Fe Mössbauer, X-band EPR, resonance Raman (rRaman), X-ray absorption, and nuclear resonance vibrational (NRVS)] and computational studies. The conversion of the diiron(II) complex 1 to the oxo diiron(IV) intermediate INT is reminiscent of the O 2 activation process in soluble methane monooxygenases (sMMO). Most importantly, the low reactivity of INT supports the consensus that the [Fe IV (μ-O) 2 Fe IV ] diamond core in sMMO is kinetically inert and needs to open up to terminal Fe IV ═O cores to react with the strong C-H bonds of methane.

Objective: Cervical cancer is the leading cause of cancer in low- and middle-income countries, despite being preventable. Uganda, which lacks an effective screening program, has one of the highest global cervical cancer incidence rates. Mobile health (mHealth) technology has the potential to improve healthcare-seeking behaviors and access. The present study describes the connection between mobile phone access and healthcare-seeking behaviors in rural Uganda., Methods: Women were eligible for this cross-sectional study if they had no prior screening or treatment for cervical cancer in the past 5 years, were aged 30 to 49 years old, and were residents of the South Busoga Forest reserve. Survey data was analyzed using descriptive statistics and chi-square tests., Results: Of the 1434 participants included in the analysis, 91.4% reported having access to a mobile phone. Most respondents were aged 30-40 years, had a partner, had ≤primary education, and were farmers. Participants with mobile phone access were significantly more likely to report attending a healthcare outreach visit (access = 87.3%, no access = 72.6%, P < 0.001) or visiting a health center (access = 96.9%, no access = 93.5%, P < 0.001). Participants in both groups had largely positive attitudes around and good knowledge of cervical cancer screening., Conclusion: While attendance to healthcare services was high amongst participants, those with mobile phone access were more likely to seek healthcare services. Further inquiry into this association between mobile phone access and healthcare-seeking behavior is needed to optimize the improvements to cervical cancer screening when implementing interventions such as mHealth technology., (© 2024 International Federation of Gynecology and Obstetrics.)

Cytochrome c oxidase (CcO) is a heme copper oxidase (HCO) that catalyzes the natural reduction of oxygen to water. A profound understanding of some of the elementary steps leading to the intricate 4e - /4H + reduction of O 2 is presently lacking. A total spin S t = 1 Fe III -(O 2 2- )-Cu II ( I P ) intermediate is proposed to reduce the overpotentials associated with the reductive O-O bond rupture by allowing electron transfer from a tyrosine moiety without the necessity of any spin-surface crossing. Direct evidence of the involvement of I P in the CcO catalytic cycle is, however, missing. A number of heme copper peroxido complexes have been prepared as synthetic models of I P , but all of them possess the catalytically nonrelevant S t = 0 ground state resulting from antiferromagnetic coupling between the S = 1/2 Fe III and Cu II centers. In a complete nonheme approach, we now report the spectroscopic characterization and reactivity of the Fe III versus -H substituent on the central amine of the tridentate ligands binding to copper. Complex 2 2- )-Cu II intermediates 1 centers performs H-bonding-mediated O-O bond cleavage in the presence of phenol to generate oxoiron(IV) and exchange-coupled copper(II) and PhO 2 , which differ only by a single -CH 3 versus -H substituent on the central amine of the tridentate ligands binding to copper. Complex 1 with an end-on peroxido core and ferromagnetically ( S t = 1) coupled Fe III and Cu II centers performs H-bonding-mediated O-O bond cleavage in the presence of phenol to generate oxoiron(IV) and exchange-coupled copper(II) and PhO • moieties. In contrast, the μ-η 2 :η 1 peroxido complex 2 , with a S t = 0 ground state, is unreactive toward phenol. Thus, the implications for spin topology contributions to O-O bond cleavage, as proposed for the heme Fe III -(O 2 2- )-Cu II intermediate in CcO, can be extended to nonheme chemistry.

Merely all transition-metal-based materials reconstruct into similar oxyhydroxides during the electrocatalytic oxygen evolution reaction (OER), severely limiting the options for a tailored OER catalyst design. In such reconstructions, initial constituent p-block elements take a sacrificial role and leach into the electrolyte as oxyanions, thereby losing the ability to tune the catalyst's properties systematically. From a thermodynamic point of view, indium is expected to behave differently and should remain in the solid phase under alkaline OER conditions. However, the structural behavior of transition metal indium phases during the OER remains unexplored. Herein, are synthesized intermetallic cobalt indium (CoIn 3 ) nanoparticles and revealed by in situ X-ray absorption spectroscopy and scanning transmission microscopy that they undergo phase segregation to cobalt oxyhydroxide and indium hydroxide. The obtained cobalt oxyhydroxide outperforms a metallic-cobalt-derived one due to more accessible active sites. The observed phase segregation shows that indium behaves distinctively differently from most p-block elements and remains at the electrode surface, where it can form lasting interfaces with the active metal oxo phases., (© 2024 The Authors. Small published by Wiley‐VCH GmbH.)

Developing Mn-based water-oxidation reaction (WOR) catalysts is key for renewable energy storage, utilizing Mn's abundance, cost-effectiveness, and natural role. Cerium(IV) ammonium nitrate (CAN) has been widely utilized as a sacrificial oxidant in the exploration of WOR catalysts. In this study, advanced techniques, such as X-ray absorption spectroscopy (XAS), in situ Raman spectroscopy, and in situ electron paramagnetic resonance (EPR), to delve into the WOR facilitated by CAN and birnessite were employed. XANES analysis has demonstrated that the average oxidation states (AOSs) of Mn in birnessite, a birnessite/CAN mixture, and in the birnessite/CAN mixture postwater addition are 3.7, 3.8, and 3.9, respectively. In situ Raman spectroscopy performed in the presence of birnessite and CAN revealed a distinct peak at 784 cm -1 , which is attributed to Mn(IV)═O. A shift of this peak to 769 cm -1 in H 2 18 O confirms its association with Mn(IV)═O. No change in this peak was observed in D 2 O, further supporting the notion that it is linked to Mn(IV)═O rather than Mn-OH (D). Furthermore, EPR spectroscopy shows the presence of Mn(IV). It is suggested that the WOR mechanism initiates with the oxidation of birnessite by CAN, which enhances the concentration of Mn(IV) sites in the birnessite structure. Under acidic conditions, birnessite, enriched in Mn(IV), facilitates oxygen evolution and subsequently transitions into a form with reduced Mn(IV) levels. This process highlights the critical function of the Mn (hydr)oxide structure, similar to its role in the water-oxidizing complex of Photosystem II, where it serves as charge storage for oxidizing equivalents from CAN, paving the way for a four-electron reaction that drives the WOR.

The development of catalysts for an economical and efficient oxygen evolution reaction (OER) is critical for clean and sustainable energy storage and conversion. Nickel-iron-based (NiFe) nanostructures are widely investigated as active OER catalysts and especially shape-controlled nanocrystals exhibit optimized surface structure and electronic properties. However, the structural control from amorphous to well-defined crystals is usually time-consuming and requires multiple stages. Here, a universal two-step precipitation-hydrothermal approach is reported to prepare a series of NiFe-based nanocrystals (e.g., hydroxides, sulfides, and molybdates) from amorphous precipitates. Their morphology and evolution of atomic and electronic structure during this process are studied using conclusive microscopy and spectroscopy techniques. The short-term, additive-free, and low-cost method allows for the control of the crystallinity of the materials and facilitates the generation of nanosheets, nanorods, or nano-octahedra with excellent water oxidation activity. The NiFe-based crystalline catalysts exhibit slightly compromised initial activity but more robust long-term stability than their amorphous counterparts during electrochemical operation. This facile, reliable, and universal synthesis method is promising in strategies for fabricating NiFe-based nanostructures as efficient and economically valuable OER electrocatalysts., (© 2023 Wiley‐VCH GmbH.)

Despite their industrial ubiquity, polyolefin-polyacrylate block copolymers are challenging to synthesize due to the distinct polymerization pathways necessary for respective blocks. This study utilizes MILRad, metal-organic insertion light-initiated radical polymerization, to synthesize polyolefin-b-poly(methyl acrylate) copolymer by combining palladium-catalyzed insertion-coordination polymerization and atom transfer radical polymerization (ATRP). Brookhart-type Pd complexes used for the living polymerization of olefins are homolytically cleaved by blue-light irradiation, generating polyolefin-based macroradicals, which are trapped with functional nitroxide derivatives forming ATRP macroinitiators. ATRP in the presence of Cu(0), that is, supplemental activators and reducing agents , is used to polymerize methyl acrylate. An increase in the functionalization efficiency of up to 71% is demonstrated in this study by modifying the light source and optimizing the radical trapping condition. Regardless of the radical trapping efficiency, essentially quantitative chain extension of polyolefin-Br macroinitiator with acrylates is consistently demonstrated, indicating successful second block formation., (© 2024 The Authors. Macromolecular Rapid Communications published by Wiley‐VCH GmbH.)

Oxide-derived copper (OD-Cu) materials exhibit extraordinary catalytic activities in the electrochemical carbon dioxide reduction reaction (CO 2 RR), which likely relates to non-metallic material constituents formed in transitions between the oxidized and the reduced material. In time-resolved operando experiment, we track the structural dynamics of copper oxide reduction and its re-formation separately in the bulk of the catalyst material and at its surface using X-ray absorption spectroscopy and surface-enhanced Raman spectroscopy. Surface-species transformations progress within seconds whereas the subsurface (bulk) processes unfold within minutes. Evidence is presented that electroreduction of OD-Cu foams results in kinetic trapping of subsurface (bulk) oxide species, especially for cycling between strongly oxidizing and reducing potentials. Specific reduction-oxidation protocols may optimize formation of bulk-oxide species and thereby catalytic properties. Together with the Raman-detected surface-adsorbed *OH and C-containing species, the oxide species could collectively facilitate *CO adsorption, resulting an enhanced selectivity towards valuable C 2+ products during CO 2 RR., (© 2024. The Author(s).)

There is limited research on how a cervical cancer diagnosis financially impacts women and their families in Uganda. This analysis aimed to describe the economic impact of cervical cancer treatment, including how it differs by socio-economic status (SES) in Uganda. We conducted a cross-sectional study from September 19, 2022 to January 17, 2023. Women were recruited from the Uganda Cancer Institute and Jinja Regional Referral Hospital, and were eligible if they were ≥ of 18 years and being treated for cervical cancer. Participants completed a survey that included questions about their out-of-pocket costs, unpaid labor, and family's economic situation. A wealth index was constructed to determine their SES. Descriptive statistics were reported. Of the 338 participants, 183 were from the lower SES. Women from the lower SES were significantly more likely to be older, have ≤ primary school education, and have a more advanced stage of cervical cancer. Over 90% of participants in both groups reported paying out-of-pocket for cervical cancer. Only 15 participants stopped treatment because they could not afford it. Women of a lower SES were significantly more likely to report borrowing money (higher SES n = 47, 30.5%; lower SES n = 84, 46.4%; p-value = 0.004) and selling possessions (higher SES n = 47, 30.5%; lower SES n = 90, 49.7%; p-value = 0.006) to pay for care. Both SES groups reported a decrease in the amount of time that they spent caring for their children since their cervical cancer diagnosis (higher SES n = 34, 31.2%; lower SES n = 36, 29.8%). Regardless of their SES, women in Uganda incur out-of-pocket costs related to their cervical cancer treatment. However, there are inequities as women from the lower SES groups were more likely to borrow funds to afford treatment. Alternative payment models and further economic support could help alleviate the financial burden of cervical cancer care in Uganda., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Dau et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Microsecond time-resolved step-scan FTIR difference spectroscopy was used to study photosystem I (PSI) from Thermosynechococcus vestitus BP-1 (T. vestitus, formerly known as T. elongatus) at 77 K. In addition, photoaccumulated (P700 + -P700) FTIR difference spectra were obtained at both 77 and 293 K. The FTIR difference spectra are presented here for the first time. To extend upon these FTIR studies nanosecond time-resolved infrared difference spectroscopy was also used to study PSI from T. vestitus at 296 K. Nanosecond infrared spectroscopy has never been used to study PSI samples at physiological temperatures, and here it is shown that such an approach has great value as it allows a direct probe of electron transfer down both branches in PSI. In PSI at 296 K, the infrared flash-induced absorption changes indicate electron transfer down the B- and A-branches is characterized by time constants of 33 and 364 ns, respectively, in good agreement with visible spectroscopy studies. These time constants are associated with forward electron transfer from A 1 - to F X on the B- and A-branches, respectively. At several infrared wavelengths flash-induced absorption changes at 296 K recover in tens to hundreds of milliseconds. The dominant decay phase is characterized by a lifetime of 128 ms. These millisecond changes are assigned to radical pair recombination reactions, with the changes being associated primarily with P700 + rereduction. This conclusion follows from the observation that the millisecond infrared spectrum is very similar to the photoaccumulated (P700 + -P700) FTIR difference spectrum., (© 2023. The Author(s).)

Background: The World Health Organization (WHO) call for cervical cancer elimination includes increasing global cervical screening coverage. HPV-based self-collection (HPV-SC) is a promising screening model for low- and middle-income countries (LMICs), and while digital technology, such as cellphones, can be used to streamline HPV-SC, there is limited data on digital technology penetration in LMICs. Determining women's cellphone access is critical to understanding the feasibility of using cellphones to support HPV-SC., Methods: This study is a secondary analysis of a larger clinical trial. Participants of a cluster-randomized trial comparing HPV-SC models in Uganda completed a survey, including questions about demographics, cellphone access/ownership, prior cervical cancer screening (CCS), and willingness to receive CCS information by text. A logistic regression model was used to determine adjusted rates of cellphone ownership using survey variables as factors., Results: Of 2019 participants, 76.1% owned a cellphone. In non-cellphone owners (n = 483), 82.4% had daily cellphone access and 7.3% had no access. Compared to non-cellphone owners, cellphone owners were significantly older, more educated, closer to major health centers, more likely to have prior CCS, and more willing to receive a CCS text. In the logistic regression model, the aforementioned variables were all significantly associated with the odds of owning a cellphone., Conclusions: As health care systems consider adopting HPV-SC, it is imperative to understand digital technology penetration. The majority of participants were cellphone owners and were willing to receive CCS information by text; however, significant socioeconomic and demographic differences remain between cellphone owners and non-owners. Further investigation is needed to understand whether HPV-SC using cellphones is feasible in similar settings., Trial Registration: ISRCTN, 12767014 ., Clinicaltrials: gov, NCT04000503 ., Competing Interests: Declarations. Ethics approval and consent to participate: Ethics approval was obtained from all partner institutions. Approval was obtained from the University of British Columbia Children and Women’s Research Ethics Board (UBC C&W REB H17-03332), Uganda Cancer Institute (UCIREC REF 08–2018), and the Uganda National Council for Science and Technology (UNCST HS 2517). Participants provided either written informed consent or a stamped fingerprint (for those unable to provide written signatures). The study conformed to the principles outlined in the Declaration of Helsinki. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Background: Uganda has one of the highest rates of cervical cancer in the world. Many women are diagnosed and treated with advanced stages of the disease. With only one facility offering comprehensive cervical cancer care in Uganda, many women are required to travel significant distances and spend time away from their homes to receive cervical cancer care. It is important to understand the burden of time away from home while attending treatment because it can inform the expansion of cervical cancer treatment programmes. The aim of this mixed-methods paper is to describe how the distance to cervical cancer treatment locations impacts women in Uganda., Methods: Women were recruited from 19 September, 2022, to 17 January, 2023, at the Uganda Cancer Institute (UCI) and the cancer clinic at Jinja Regional Referral Hospital (JRRF). Women were eligible for the study if they were (i) aged ≥18 years with a histopathologic diagnosis of cervical cancer; (ii) being treated at the UCI or JRRF for cervical cancer; and (iii) able to provide consent to participate in the study in English, Luganda, Lusoga, Luo, or Runyankole. All participants completed a quantitative survey and a selected group was sampled for semi-structured interviews. Data were analysed using the convergent parallel mixed-methods approach. Descriptive statistics were reported for the quantitative data and qualitative data using an inductive-deductive thematic analysis approach., Results: In all, 351 women participated in the quantitative section of the study and 24 in the qualitative. The quantitative and qualitative findings largely aligned and supported one another. Women reported travelling up to 14 h to receive treatment and 20% noted that they would spend three or more nights away from home during their current visit. Major themes of the qualitative include means of transportation, spending the night away from home, and financial factors., Conclusion: Our findings show that travelling to obtain cervical cancer care can be a significant burden for women in Uganda. Approaches should be considered to reduce this burden such as additional satellite cervical cancer clinics or subsidised transportation options., (© 2023 The Authors Tropical Medicine & International Health Published by John Wiley & Sons Ltd.)

Recently, Ni molecular catalysis has been extensively applied in oxygenation reactions. This work is underpinned by the characterization techniques and the discovered instability of the Ni-bipyridine/phenanthroline system, which results in Ni (hydr)oxide production under oxidative conditions. The practical applications of this mechanism by employing a prepared Ni (hydr)oxide-based electrode specifically in the oxygenation of sulfides, achieving noteworthy yields in contrast to noncatalyst control experiments, are explored. Thus, a Ni (hydr)oxide-based material is proposed as a candidate for the true catalyst for sulfide oxidation in the presence of the Ni-bipyridine/phenanthroline system. The findings of this study are expected to stimulate discussion and encourage new viewpoints within the chemical community regarding the potential applications and mechanisms of molecular catalysts in oxidation reactions.

The N 3 O macrocycle of the 12-TMCO ligand stabilizes a high spin ( S = 5/2) [Fe III (12-TMCO)(OO t Bu)Cl] + (3-Cl) species in the reaction of [Fe II (12-TMCO)(OTf) 2 ] (1-(OTf) 2 ) with tert -butylhydroperoxide ( t BuOOH) in the presence of tetraethylammonium chloride (NEt 4 Cl) in acetonitrile at -20 °C. In the absence of NEt 4 Cl the oxo-iron(iv) complex 2 [Fe IV (12-TMCO)(O)(CH 3 CN)] 2+ is formed, which can be further converted to 3-Cl by adding NEt 4 Cl and t BuOOH. The role of the cis -chloride ligand in the stabilization of the Fe III -OO t Bu moiety can be extended to other anions including the thiolate ligand relevant to the enzyme superoxide reductase (SOR). The present study underlines the importance of subtle electronic changes and secondary interactions in the stability of the biologically relevant metal-dioxygen intermediates. It also provides some rationale for the dramatically different outcomes of the chemistry of iron(iii)peroxy intermediates formed in the catalytic cycles of SOR (Fe-O cleavage) and cytochrome P450 (O-O bond lysis) in similar N 4 S coordination environments., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Cervical cancer is a leading cause of cancer among women in low- and middle-income countries. Women in Rwanda have high rates of cervical cancer due to limited access to effective screening methods. Research in other low-resource settings similar to Rwanda has shown that HPV-based self-collection is an effective cervical cancer screening method. This study aims to compare the preferences of Rwandan women in urban and rural settings toward self-collection and to report on factors related to self-collection amenability. A cross-sectional survey was conducted from June 1-9, 2022. Women were recruited from one urban and one rural clinic in Rwanda. Women were eligible for the study if they were ≥ 18 years and spoke Kinyarwanda or English. The survey consisted of 51 questions investigating demographics and attitudes towards self-collection for cervical cancer screening. We reported descriptive statistics stratified by urban and rural sites. In total, 169 urban and 205 rural women completed the survey. The majority of respondents at both sites had a primary school or lower education and were in a relationship. Both urban and rural respondents were open to self-collection; however, rates were higher in the rural site (79.9% urban and 95.6% rural; p-value<0.001). Similarly, women in rural areas were more likely to report feeling unembarrassed about self-collection (65.3% of urban, 76.8% of rural; p-value<0.001). Notably, almost all urban and rural respondents (97.6% urban and 98.5% rural) stated they would go for a cervical cancer pelvic examination to a nearby health center if their self-collected results indicated any concern (p-value = 0.731). Rwandan women in both urban and rural areas largely support self-collection for cervical cancer screening. Further research is needed to better understand how to implement self-collection screening services in Rwanda., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Nair et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Cervical cancer is the leading cause of cancer mortality in Rwandan women. There is a limited understanding of the barriers that women face to obtain cervical cancer screening in Rwanda. It is important to understand the barriers in order to implement effective screening programs. The goal of this study is to describe the barriers to cervical cancer screening among women in Rwanda and how they differ among women in rural and urban areas., Methods: This cross-sectional study recruited women from June 1 to 9, 2022, at Muhima and Nyamata District Hospitals in Rwanda. Women were eligible for the study if they were ≥ 18 years and spoke Kinyarwanda or English. Women completed a 15-min survey which included questions on the participants' demographics, knowledge of cervical cancer, cervical cancer screening history, and barriers to healthcare. Women were stratified by survey location (urban vs rural). Descriptive statistics were reported., Results: A total of 374 women completed the survey with 169 participants from Muhima and 205 from Nyamata. Most women were in a relationship and had a primary school or less education. The most common barriers to accessing general healthcare services were long wait times at the facility (Muhima 26%; Nyamata 30%), low quality of care (Muhima 15%; Nyamata 12%), and transportation costs (Muhima 13%; Nyamata 9.3%). However, women from Nyamata were significantly more likely to report distance to the health center as a barrier (p-value < 0.001), and women from Muhima were significantly more likely to report transportation method as a barrier (p-value = 0.004). The primary reason reported for not obtaining cervical cancer screening was that women did not know how or where to get tested (Muhima 57%; Nyamata 51%)., Conclusions: The most common barriers to cervical cancer screening in Rwanda were the quality of clinical care and issues with traveling to the clinic. Implementing a cervical cancer self-collection program could help eliminate many barriers that women face to obtain health services in Rwanda. More research is needed to better understand the acceptability of cervical cancer screening in Rwanda and how it could be integrated into the healthcare system., Competing Interests: Declarations. Ethics approval and consent to participate: Ethical approval was obtained from the University of British Columbia (H22-01335) and Rwanda National Ethics Committee (125/RNEC/2022). Written informed consent was obtained from all participants. Research conformed to the principles of the Helsinki Declaration. Additionally, each hospital was provided with 150,000 Rwanda Franc ($140 USD) by the study team as a token of appreciation for their participation in the study. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2023. The Author(s).)

Metal complexes are extensively explored as catalysts for oxidation reactions; molecular-based mechanisms are usually proposed for such reactions. However, the roles of the decomposition products of these materials in the catalytic process have yet to be considered for these reactions. Herein, the cyclohexene oxidation in the presence of manganese(III) 5,10,15,20-tetra(4-pyridyl)-21H,23H-porphine chloride tetrakis(methochloride) (1) in a heterogeneous system via loading the complex on an SBA-15 substrate is performed as a study case. A molecular-based mechanism is usually suggested for such a metal complex. Herein, 1 was selected and investigated under the oxidation reaction by iodosylbenzene or (diacetoxyiodo)benzene (PhI(OAc) 2 ). In addition to 1, at least one of the decomposition products of 1 formed during the oxidation reaction could be considered a candidate to catalyze the reaction. First-principles calculations show that Mn dissolution is energetically feasible in the presence of iodosylbenzene and trace amounts of water., (© 2023. The Author(s).)

Objective: The study objective was to assess mental and social health outcomes for individuals with rheumatic disease during the COVID-19 pandemic and evaluate the relationship of loneliness and social isolation with depression and anxiety., Methods: We administered an international cross-sectional online survey to individuals with rheumatic disease(s) (≥18 years) between April 2020 and September 2020, with a follow-up survey from December 2020 to February 2021. We used questionnaires to evaluate loneliness (3-item UCLA Loneliness Scale [UCLA-3]), social isolation (Lubben Social Network Scale [LSNS-6]), depression (Patient Health Questionnaire [PHQ-9]), and anxiety (Generalized Anxiety Disorder 7-item [GAD-7] Scale). We used multivariable linear regression models to evaluate the cross-sectional associations of loneliness and social isolation with depression and anxiety at baseline., Results: Seven hundred eighteen individuals (91.4% women, mean age: 45.4 ± 14.2 years) participated in the baseline survey, and 344 completed the follow-up survey. Overall, 51.1% of participants experienced loneliness (UCLA-3 score ≥6) and 30.3% experienced social isolation (LSNS-6 score <12) at baseline. Depression (PHQ-9 score ≥10) and anxiety (GAD-7 score ≥10) were experienced by 42.8% and 34.0% of participants at baseline, respectively. Multivariable models showed that experiencing both loneliness and social isolation, in comparison to experiencing neither, was significantly associated with an average 7.27 higher depression score (ß = 7.27; 95% confidence interval [CI]: 6.08-8.47) and 5.14 higher anxiety score (ß = 5.14; 95% CI: 4.00-6.28)., Conclusion: Aside from showing substantial experience of loneliness and social isolation during the COVID-19 pandemic, our survey showed significant associations with depression and anxiety. Patient supports to address social health have potential implications for also supporting mental health., (© 2023 The Authors. ACR Open Rheumatology published by Wiley Periodicals LLC on behalf of American College of Rheumatology.)

Photosynthesis fuels life on Earth by storing solar energy in chemical form. Today's oxygen-rich atmosphere has resulted from the splitting of water at the protein-bound manganese cluster of photosystem II during photosynthesis. Formation of molecular oxygen starts from a state with four accumulated electron holes, the S 4 state-which was postulated half a century ago 1 and remains largely uncharacterized. Here we resolve this key stage of photosynthetic O 2 formation and its crucial mechanistic role. We tracked 230,000 excitation cycles of dark-adapted photosystems with microsecond infrared spectroscopy. Combining these results with computational chemistry reveals that a crucial proton vacancy is initally created through gated sidechain deprotonation. Subsequently, a reactive oxygen radical is formed in a single-electron, multi-proton transfer event. This is the slowest step in photosynthetic O 2 formation, with a moderate energetic barrier and marked entropic slowdown. We identify the S 4 state as the oxygen-radical state; its formation is followed by fast O-O bonding and O 2 release. In conjunction with previous breakthroughs in experimental and computational investigations, a compelling atomistic picture of photosynthetic O 2 formation emerges. Our results provide insights into a biological process that is likely to have occurred unchanged for the past three billion years, which we expect to support the knowledge-based design of artificial water-splitting systems., (© 2023. The Author(s).)

Purpose: There is currently no information on how caregivers for women diagnosed with cervical cancer in Guatemala, particularly daughters, are affected by their supportive role. This study's objective was to describe the support role of caregivers in the country, with a focus on daughters with a mother diagnosed with cervical cancer., Methods: This analysis utilizes data from a cross-sectional study which aimed to understand pathways to cervical cancer care. Women seeking cervical cancer treatment at the Instituto de Cancerologia (INCAN) in Guatemala City, Guatemala and their companions were surveyed. Descriptive statistics were calculated., Results: One hundred forty-five women seeking treatment and 71 companions participated in the study. Patient's daughters were most frequently reported as the person who provided the most support (51%) and as the most reported to have encouraged the patient to seek care. Furthermore, daughters were noted as the person most reported to fulfill the major household and livelihood roles of the patient while they were seeking or receiving treatment (38.0%). Most daughters reported that they were missing housework (77%), childcare (63%), and income-earning activities (60%) to attend the appointment with their mothers., Conclusion: Our study suggests that in Guatemala cervical cancer patient's daughters have a significant support role in their mother's cancer diagnosis. Furthermore, we found that while caring for their mothers, daughters in Guatemala are often unable to participate in their primary labor activities. This highlights the additional burden that cervical cancer has on women in Latin America., (© 2023. The Author(s).)

In class Ib ribonucleotide reductases (RNRs) a dimanganese(II) cluster activates superoxide (O 2 ⋅ - ) rather than dioxygen (O 2 ), to access a high valent Mn III -O 2 -Mn IV species, responsible for the oxidation of tyrosine to tyrosyl radical. In a biomimetic approach, we report the synthesis of a thiolate-bound dimanganese complex [Mn II 2 (BPMT)(OAc) 2 ](ClO) 4 (BPMT=(2,6-bis{[bis(2-pyridylmethyl)amino]methyl}-4-methylthiophenolate) (1) and its reaction with O 2 ⋅ - to form a [(BPMT)MnO 2 Mn] 2+ complex 2. Resonance Raman investigation revealed the presence of an O-O bond in 2, while EPR analysis displayed a 16-line S t =1/2 signal at g=2 typically associated with a Mn III Mn IV core, as detected in class Ib RNRs. Unlike all other previously reported Mn-O 2 -Mn complexes, generated by O 2 ⋅ - activation at Mn 2 centers, 2 proved to be a capable electrophilic oxidant in aldehyde deformylation and phenol oxidation reactions, rendering it one of the best structural and functional models for class Ib RNRs., (© 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Objectives: To understand the relationship between informed choice and long-acting reversible contraceptive (LARC) use among women aged 15-49 years in Uganda after adjusting for potential confounding., Methods: This cross-sectional study uses data from the 2016 Uganda Standard Demographic and Health Survey. Thomas-Rao corrections to a χ 2 test were used for the bivariable analysis. A design-adjusted multivariable logistic regression was used to estimate the association between informed choice and LARC use. Propensity score matching was conducted as a sensitivity analysis., Results: In all, 3646 women were included in the analysis and 975 reported using a LARC. In the design-adjusted multivariable analysis, the odds of reporting LARC usage were 1.98 (95% confidence interval 1.61-2.43) times higher among women who reported informed choice compared with those who did not. The subsequent propensity score analysis reported similar findings., Conclusion: Providing informed choice can help to increase the number of women who use LARC in Uganda. As such, the Ugandan Ministry of Health should further expand access to family planning counseling as it could contribute to the reduction of unplanned pregnancies across Uganda with the use of LARC., (© 2022 International Federation of Gynecology and Obstetrics.)

Background: There is limited knowledge on the social and economic impacts of a diagnosis of cervical cancer on women and children in low- and middle-income countries (LMICs)., Objectives: To determine the social and economic impacts associated with cervical cancer among women and children living in LMICs., Search Strategy: The MEDLINE, PsychInfo, CINAHL, Pais International, and CAB Global Health databases were systematically searched to retrieve studies up to June 2021., Selection Criteria: Studies were included if they reported on either the social or economic impacts of women or children in a LMIC., Data Collection and Analysis: Data was independently extracted by two co-authors. The authors performed a quality assessment on all included articles., Main Results: In all, 53 studies were included in the final review. Social impacts identified included social support, education, and independence. Economic impacts included employment and financial security. No study reported the economic impact on children. Studies that utilized quantitative methods typically reported more positive results than those that utilized qualitative methods., Conclusions: Additional mixed-methods research is needed to further understand the social support needs of women with cervical cancer. Furthermore, research is needed on the impact of a mother's diagnosis of cervical cancer on her children., (© 2022 International Federation of Gynecology and Obstetrics.)

Diiron cofactors in enzymes perform diverse challenging transformations. The structures of high valent intermediates (Q in methane monooxygenase and X in ribonucleotide reductase) are debated since Fe-Fe distances of 2.5-3.4 Å were attributed to "open" or "closed" cores with bridging or terminal oxido groups. We report the crystallographic and spectroscopic characterization of a Fe III 2 (μ-O) 2 complex (2) with tetrahedral (4C) centres and short Fe-Fe distance (2.52 Å), persisting in organic solutions. 2 shows a large Fe K-pre-edge intensity, which is caused by the pronounced asymmetry at the T D Fe III centres due to the short Fe-μ-O bonds. A ≈2.5 Å Fe-Fe distance is unlikely for six-coordinate sites in Q or X, but for a Fe 2 (μ-O) 2 core containing four-coordinate (or by possible extension five-coordinate) iron centres there may be enough flexibility to accommodate a particularly short Fe-Fe separation with intense pre-edge transition. This finding may broaden the scope of models considered for the structure of high-valent diiron intermediates formed upon O 2 activation in biology., (© 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

A hydrogen processing strategy is developed to enable bulk LaNi 5 to attain high activity and long-term stability toward the electrocatalytic oxygen evolution reaction (OER). By a combination of in situ Raman and quasi in situ X-ray absorption (XAS) spectra, secondary-electron-excited scanning transmission electron microscopy (STEM) patterns as well as the Rietveld method and density functional theory (DFT) calculations, it is discovered that hydrogen-induced lattice distortion, grain refinement, and particle cracks dictate the effective reconstruction of the LaNi 5 surface into a porous hetero-nanoarchitecture composed of uniformly confined active γ-NiOOH nanocrystals by La(OH) 3 layer in the alkaline OER process. This significantly optimizes the charge transfer, structural integrity, active-site exposure, and adsorption energy toward the reaction intermediates. Benefiting from these merits, the overpotential (322 mV) at 100 mA cm -2 for the hydrogen-processed OER catalyst deposited on nickel foam is reduced by 104 mV as compared to the original phase. Notably, it exhibits remarkable stability for 10 days at an industrial-grade current density of more than 560 mA cm -2 in alkaline media., (© 2023 The Authors. Advanced Materials published by Wiley-VCH GmbH.)