Endogenous Interfacial Mo-C/N-Mo-S Bonding Regulates the Active Mo Sites for Maximized Li+ Storage Areal Capacity

Active sites, mass loading, and Li-ion diffusion coefficient are the benchmarks for boosting the areal capacity and storage capability of electrode materials for lithium-ion batteries. However, simultaneously modulating these criteria to achieve high areal capacity in LIBs remains challenging. Herein, MoS2 is considered as a suitable electroactive host material for reversible Li-ion storage and establish an endogenous multi-heterojunction strategy with interfacial Mo-C/N-Mo-S coordination bonding that enables the concurrent regulation of these benchmarks. This strategy involves architecting 3D integrated conductive nanostructured frameworks composed of Mo2 C-MoN@MoS2 on carbon cloth (denoted as C/MMMS) and refining the sluggish kinetics in the MoS2 -based anodes. Benefiting from the rich hetero-interface active sites, optimized Li adsorption energy, and low diffusion barrier, C/MMMS reaches a mass loading of 12.11 mg cm-2 and showcases high areal capacity and remarkable rate capability of 9.6 mAh cm-2 @0.4 mA cm-2 and 2.7 mAh cm-2 @6.0 mA cm-2 , respectively, alongside excellent stability after 500 electrochemical cycles. Moreover, this work not only affirms the outstanding performance of the optimized C/MMMS as an anode material for supercapacitors, underscoring its bifunctionality but also offers valuable insight into developing endogenous transition metal compound electrodes with high mass loading for the next-generation high areal capacity energy storage devices.

Unlatching the Additional Zinc Storage Ability of Vanadium Nitride Nanocrystallites

Vanadium-based materials, due to their diverse valence states and open-framework lattice, are promising cathodes for aqueous zinc ion batteries (AZIBs), but encounters the major challenges of in situ electrochemical activation process, potent polarity of the aqueous electrolyte and periodic expansion/contraction for efficient Zn2+ storage. Herein, architecting vanadium nitride (VN) nanosheets over titanium-based hollow nanoarrays skeletal host (denoted VNTONC) can simultaneously modulate address those challenges by creating multiple interfaces and maintaining the (1 1 1) phase of VN, which optimizes the Zn2+ storage and the stability of VN. Benefiting from the modulated crystalline thermodynamics during the electrochemical activation of VN, two outcomes are achieved; I) the cathode transforms into a nanocrystalline structure with increased active sites and higher conductivity and; II) a significant portion of the (1 1 1) crystal facets is retained in the process leading to the additional Zn2+ storage capacity. As a result, the as-prepared VNTONC electrode demonstrates remarkable discharge capacities of 802.5 and 331.8 mAh g-1 @ 0.5 and 6.0 A g-1 , respectively, due to the enhanced kinetics as validated by theoretical calculations. The assembled VNTONC||Zn flexible ZIB demonstrates excellent Zn storage properties up to 405.6 mAh g-1 , and remarkable robustness against extreme operating conditions.

The Ebola outbreak: effects on HIV reporting, testing and care in Bonthe district, rural Sierra Leone

Setting: All public health facilities in Bonthe District, rural Sierra Leone. Objective: To compare, in the periods before and during the Ebola virus disease outbreak, 1) the submission and completeness of monthly human immunodeficiency virus (HIV) reports, and 2) the uptake of HIV testing and care for pregnant women and the general population. Design: A cross-sectional study using routine programme data. Results: Of the 627 HIV reports expected in each period, 406 (65%) were submitted in the pre-Ebola period and 376 (60%) during the Ebola outbreak (P = 0.08), of which respectively 318 (78%) and 335 (89%) had complete information (P < 0.001). In the pre-Ebola period, 5012 pregnant women underwent testing for HIV, of whom 25 were HIV-positive, compared to 4254 during the Ebola period, of whom 21 were HIV-positive (P < 0.001). Of those who were HIV-positive, respectively 14 (56%) and 21 (100%) received antiretroviral prophylaxis or antiretroviral therapy (ART) (P < 0.001). In the general population, 5770 persons underwent HIV testing pre-Ebola vs. 3095 in the Ebola period (P < 0.001); of those who tested positive for HIV, respectively 62% (33/53) and 81% (33/41) were started on ART (P = 0.06). Conclusion: There was suboptimal reporting on HIV/acquired immune-deficiency disease syndrome activities before and during the Ebola virus disease outbreak. HIV testing decreased during the Ebola outbreak, while the uptake of prevention of mother-to-child transmission and ART increased. Pre-emptive actions are needed to maintain the levels of HIV testing in any future outbreak.

Failure mode and effects analysis of the universal anaesthesia machine in two tertiary care hospitals in Sierra Leone

Background

Anaesthesia care in developed countries involves sophisticated technology and experienced providers. However, advanced machines may be inoperable or fail frequently when placed into the austere medical environment of a developing country. Failure mode and effects analysis (FMEA) is a method for engaging local staff in identifying real or potential breakdowns in processes or work systems and to develop strategies to mitigate risks.

Methods

Nurse anaesthetists from the two tertiary care hospitals in Freetown, Sierra Leone, participated in three sessions moderated by a human factors specialist and an anaesthesiologist. Sessions were audio recorded, and group discussion graphically mapped by the session facilitator for analysis and commentary. These sessions sought to identify potential barriers to implementing an anaesthesia machine designed for austere medical environments—the universal anaesthesia machine (UAM)—and also engaging local nurse anaesthetists in identifying potential solutions to these barriers.

Results

Participating Sierra Leonean clinicians identified five main categories of failure modes (resource availability, environmental issues, staff knowledge and attitudes, and workload and staffing issues) and four categories of mitigation strategies (resource management plans, engaging and educating stakeholders, peer support for new machine use, and collectively advocating for needed resources).

Conclusions

We identified factors that may limit the impact of a UAM and devised likely effective strategies for mitigating those risks.

Cerebral vasculitis and Cardiobacterium valvarum endocarditis

We present a case of aortic and tricuspid native valve endocarditis in which Cardiobacterium valvarum was isolated from the blood culture of a 65-year-old man. Cardiobacterium valvarum is a fastidious, Gram-negative bacillus. The genus Cardiobacterium encompasses two species - Cardiobacterium valvarum and Cardiobacterium hominis. Although both species rarely feature as the aetiological agent of endocarditis, Cardiobacterium hominis has a higher incidence than Cardiobacterium valvarum. For this causative organism, we believe this is the first report of fatality prior to surgical intervention and the first clinical course to be complicated by cerebral vasculitis. Native valve endocarditis caused by Gram-negative bacilli is extremely rare and identification of isolates may require the use of reference laboratories with molecular identification techniques.