The biology of SARS-CoV-2 and epidemiological analysis of COVID-19 pandemic in Nigeria.

The pandemic triggered by SARS-CoV-2 continuous to pose a global health threat, with cases of new infections and deaths still occurring despite increasing vaccination efforts. As in other regions of the world, the pandemic has led to unprecedented stretch of health and economic systems in countries in Africa. Nigeria, the most populous African country, has not been spared as the number of new infections continues to teeter amid a high level of vaccination hesitancy. Here, we provided a brief look at the background and biology of the virus. We also highlighted the epidemiology of the virus in Nigeria, as well as the challenges and opportunities it presents. Our review will add to the knowledge of SARS-CoV-2 and the situation of the pandemic in Nigeria, and provide a better response to the pandemic and future pandemics.

Pilot parallel randomised controlled trial of protective socks against usual care to reduce skin tears in high risk people: 'STOPCUTS'.

BACKGROUND: Skin tears are common in older adults and those taking steroids and warfarin. They are traumatic, often blunt injuries caused by oblique knocks to the extremities. The epidermis may separate from the dermis or both layers from underlying tissues leaving a skin flap or total loss of tissue, which is painful and prone to infection. 'Dermatuff™' knee-length socks containing Kevlar fibres (used in stab-proof vests and motorcyclists' clothing) aim to prevent skin tears. The acceptability of the socks and the feasibility of a randomised controlled trial (RCT) had not been explored. METHODS: In this pilot parallel group RCT, 90 people at risk of skin-tear injury from Devon care homes and primary care were randomised to receive the socks or treatment as usual (TAU). The pilot aimed to estimate parameters to inform the design of a substantive trial and record professionals' views and participants' acceptability of the intervention and of study participation. RESULTS: Participants were randomised from July 2013 and followed up until February 2015. Community participants were easier to recruit than care homes residents but were 10 years younger on average and more active. To recruit 90 participants, 395 had to be approached overall as 77% were excluded or declined. Seventy-nine participants (88%) completed the trial and 27/44 (61%) wore the socks for 16 weeks. There were 31 skin tear injuries affecting 18 (20%) of the 90 participants. The TAU group received more injuries, more repeated episodes, and larger tears with greater severity. Common daily diary reasons for not wearing the socks included perceived warmth in hot weather or not being available (holiday, in hospital, bed rest). Resource use data were obtainable and indicated that sock wearing gave a reduction in treatment costs whilst well-completed questionnaires showed improvements in secondary outcomes. CONCLUSIONS: This pilot trial has successfully informed the design and conduct of a future definitive cost-effectiveness RCT. It would need to be conducted in primary care with 880 active at-risk, elderly patients (440 per arm). Skin tear incidence and quality of life (from EQ5D5L) over a 4-month period would be the primary and secondary outcomes respectively. TRIAL REGISTRATION: ISRCTN, ISRCTN96565376.

The Barnstaple Leg Club, Devon.

Andrew Kingsley, Sylvie Hampton, Ellie Lindsay and Roland Renyi discuss how the social model of care has proved its worth in the South West of England.

Aerosol-assisted CVD of SnO from stannous alkoxide precursors.

The stannous alkoxides [Sn(OR)2] [R = i-Pr, t-Bu, C(Et)Me2, CHPh2, CPh3] have been synthesised by reaction of Sn(NR'2)2 with two equivalents of HOR [R' = Me, R = i-Pr; R' = SiMe3, R = t-Bu, C(Et)Me2, CHPh2, CPh3]. Single crystal X-ray diffraction analysis of the bis(diphenylmethoxide) (4) and bis(triphenylmethoxide) (5) species have shown them to comprise three-coordinate Sn(ii) centres through dimerisation in the solid state with the alkoxide units adopting transoid and cisoid configurations across the {Sn2O2} cores respectively. Thermogravimetric analysis indicates clean decomposition and some evidence of volatility at temperatures >200 °C for all three aliphatic alkoxides, whereas both the diphenyl- and triphenylmethoxide compounds provide higher decomposition temperatures and, for the triphenylmethoxide derivative, a residual mass consistent with the formation of a carbon-containing residue. The previously reported iso-propoxide (1) and tert-butoxide (2) derivatives have been utilised in toluene solution to deposit SnO thin films by aerosol-assisted chemical vapour deposition (AACVD) on glass at temperatures between 300 and 450 °C. While SnO is deposited under hot wall conditions as the only identifiable phase by p-XRD and Raman spectroscopy for both precursors, morphological analysis by SEM reveals inferior substrate coverage in comparison to previously reported ureide-based precursor systems.

Cobalt(I) Olefin Complexes: Precursors for Metal-Organic Chemical Vapor Deposition of High Purity Cobalt Metal Thin Films.

We report the synthesis and characterization of a family of organometallic cobalt(I) metal precursors based around cyclopentadienyl and diene ligands. The molecular structures of the complexes cyclopentadienyl-cobalt(I) diolefin complexes are described, as determined by single-crystal X-ray diffraction analysis. Thermogravimetric analysis and thermal stability studies of the complexes highlighted the isoprene, dimethyl butadiene, and cyclohexadiene derivatives [(C5H5)Co(η(4)-CH2CHC(Me)CH2)] (1), [(C5H5)Co(η(4)-CH2C(Me)C(Me)CH2)] (2), and [(C5H5)Co(η(4)-C6H8)] (4) as possible cobalt metal organic chemical vapor deposition (MOCVD) precursors. Atmospheric pressure MOCVD was employed using precursor 1, to synthesize thin films of metallic cobalt on silicon substrates under an atmosphere (760 torr) of hydrogen (H2). Analysis of the thin films deposited at substrate temperatures of 325, 350, 375, and 400 °C, respectively, by scanning electron microscopy and atomic force microscopy reveal temperature-dependent growth features. Films grown at these temperatures are continuous, pinhole-free, and can be seen to be composed of hexagonal particles clearly visible in the electron micrograph. Powder X-ray diffraction and X-ray photoelectron spectroscopy all show the films to be highly crystalline, high-purity metallic cobalt. Raman spectroscopy was unable to detect the presence of cobalt silicides at the substrate/thin film interface.

Pilot randomised controlled trial of protective socks against usual care to reduce skin tears in high risk people "STOPCUTS": study protocol.

BACKGROUND: Skin tears are traumatic injuries occurring mostly on the extremities due to shearing and friction forces that separate the epidermis and the dermis from underlying tissues. They are common and occur mostly in older adults and those taking medications that compromise skin integrity. Pretibial skin tears can develop into leg ulcers, which require lengthy, expensive treatment to heal. Traumatic injuries are the second most common type of wounds after pressure ulcers in care homes and are the commonest reason for older adults to require the attention of a community nurse. Common causes of skin tear injuries are bumping into furniture and other obstacles, using mobility aids, transfer to/from wheelchairs, getting in and out of bed and falls. No effective preventative measures currently exist but knee-length, protective socks are now available that contain impact-resistant Kevlar fibres (of the type used in stab-proof vests) and cushioning layers underneath. METHODS/DESIGN: In this pilot parallel group, randomised controlled trial, 90 people at risk of skin-tear injury will be randomised with equal allocation to receive the intervention or usual care. They will be recruited from care homes and from the community via general practices and a research volunteer database. Pilot outcomes include recruitment, eligibility, attrition, ascertainment of injuries and completion of outcome measures. Acceptability of the intervention and of study participation will be explored using semi-structured interviews. The proposed primary outcome for the future definitive trial is skin tear-free days. Secondary outcomes are skin tear severity, health status, specific skin-tears quality of life, capability and fear of falling, measured at baseline and the end of the study and in the event of a skin tear. DISCUSSION: The results of this study will be used to inform the development and design of a future randomised controlled trial to assess the effectiveness and cost-effectiveness of a unique and innovative approach to skin tear prevention. Approval was granted by the NRES - Cornwall and Plymouth Research Ethics Committee (13/SW/013). Dissemination will include publication of quantitative and qualitative findings, and experience of public involvement in peer-reviewed journals. TRIAL REGISTRATION: Current Controlled Trials: ISRCTN96565376.

Cobalt(III) diazabutadiene precursors for metal deposition: nanoparticle and thin film growth.

We report the synthesis and characterization of a family of cobalt(III) metal precursors, based around cyclopentadienyl and diazabutadiene ligands. The molecular structure of the complexes cyclopentadienyl-Cobalt(III)(N,N'-dicyclohexyl-diazabutadiene) (2c) and cyclopentadienyl-Cobalt(III)(N,N'-dimesityl-diazabutadiene) (2d) are described, as determined by single crystal X-ray diffraction analysis. Thermogravimetric analysis of the complexes highlighted the isopropyl derivative CpCo((i)Pr2-dab) (2a) as a possible cobalt metal chemical vapor deposition (CVD) precursor. Atmospheric pressure CVD (AP-CVD) was employed using precursor 2a to synthesize thin films of metallic cobalt on silicon substrates under an atmosphere of hydrogen (H2). Analysis of the thin films deposited at substrate temperatures of 250 °C, 275 °C, 300 °C, 325 °C, and 350 °C, respectively, by scanning electron microscopy (SEM) and atomic force microscopy (AFM) reveal temperature dependent growth features: films grown at 325 and 350 °C are continuous and pinhole free, whereas those films grown at substrate temperatures of 250 °C, 275 °C, and 300 °C consist of crystalline nanoparticles. Powder X-ray diffraction (PXRD) and X-ray photoelectron spectroscopy (XPS) all show the films to be high purity metallic cobalt. Raman spectroscopy has also been used to prove the absence of cobalt silicides at the substrate/thin film interface.

Exclusive formation of SnO by low temperature single-source AACVD.

An easily synthesised Sn(II) bis(ureide) derivative is shown to be a single-source precursor for the aerosol-assisted CVD of SnO, providing unprecedented levels of oxidation state control at temperatures as low as 250 °C.

CVD of pure copper films from novel iso-ureate complexes.

We report the synthesis and characterisation of a new family of copper(i) metal precursors based around alkoxy-N,N'-di-alkyl-ureate ligands, and their subsequent application in the production of pure copper thin films. The molecular structure of the complexes bis-copper(i)(methoxy-N,N'-di-isopropylureate) (1) and bis-copper(i)(methoxy-N,N'-di-cyclohexylureate)(5) are described, as determined by single crystal X-ray diffraction analysis. Thermogravimetric analysis of the complexes highlighted complex 1 as a possible copper CVD precursor. Low pressure chemical vapour deposition (LP-CVD) was employed using precursor 1, to synthesise thin films of metallic copper on ruthenium substrates under an atmosphere of hydrogen (H2). Analysis of the thin films deposited at substrate temperatures of 225 °C, 250 °C and 300 °C, respectively, by SEM and AFM reveal the films to be continuous and pin hole free, and show the presence of temperature dependent growth features on the surface of the thin films. Energy dispersive X-ray spectroscopy (EDX), powder X-ray diffraction (PXRD) and X-ray photoelectron spectroscopy (XPS) all show the films to be high purity metallic copper.

Multinuclear copper(I) guanidinate complexes.

A series of multinuclear Copper(I) guanidinate complexes have been synthesized in a succession of reactions between CuCl and the lithium guanidinate systems Li{L} (L = Me(2)NC((i)PrN)(2) (1a), Me(2)NC(CyN)(2) (1b), Me(2)NC((t)BuN)(2)(1c), and Me(2)NC(DipN)(2) (2d) ((i)Pr = iso-propyl, Cy = cyclohexyl, (t)Bu = tert-butyl, and Dip = 2,6-disopropylphenyl) made in situ, and structurally characterized. The di-copper guanidinates systems with the general formula [Cu(2){L}(2)] (L = {Me(2)NC((i)PrN)(2)} (2a), {Me(2)NC(CyN)(2)} (2b), and {Me(2)NC(DipN)(2)} (2d) differed significantly from related amidinate complexes because of a large torsion of the dimer ring, which in turn is a result of transannular repulsion between adjacent guanidinate substituents. Attempts to synthesis the tert-butyl derivative [Cu(2){Me(2)NC((t)BuN)(2)}(2)] result in the separate formation and isolation of the tri-copper complexes [Cu(3){Me(2)NC((t)BuN)(2)}(2)(µ-NMe(2))] (3c) and [Cu(3){Me(2)NC((t)BuN)(2)}(2)(µ-Cl)] (4c), both of which have been unambiguously characterized by single crystal X-ray diffraction. Closer inspection of the solution state behavior of the lithium salt 1c reveals a previously unobserved equilibrium between 1c and its starting materials, LiNMe(2) and N,N'-di-tert-butyl-carbodiimide, for which activation enthalpy and entropy values of ΔH(‡) = 48.2 ± 18 kJ mol(-1) and ΔS(‡) = 70.6 ± 6 J/K mol have been calculated using 1D-EXSY NMR spectroscopy to establish temperature dependent rates of exchange between the species in solution. The molecular structures of the lithium complexes 1c and 1d have also been determined and shown to form tetrameric and dimeric complexes respectively held together by Li-N and agostic Li···H-C interactions. The thermal chemistry of the copper complexes have also been assessed by thermogravimetric analysis.

Synthesis, characterization, and materials chemistry of Group 4 silylimides.

This paper focuses on the development of potential single source precursors for M-N-Si (M = Ti, Zr or Hf) thin films. The titanium, zirconium, and hafnium silylimides (Me(2)N)(2)MNSiR(1)R(2)R(3) [R(1) = R(2) = R(3) = Ph, M = Ti(1), Zr (2), Hf (3); R(1) = R(2) = R(3) = Et, M = Ti (4), Zr (5), Hf (6); R(1) = R(2) = Me, R(3) = (t)Bu, M = Ti (7), Zr (8), Hf (9); R(1) = R(2) = R(3) = NMe(2), M = Ti (10), Zr (11), Hf (12)] have been synthesized by the reaction of M(NMe(2))(4) and R(3)R(2)R(1)SiNH(2). All compounds are notably sensitive to air and moisture. Compounds 1, 2, 4, and 7-10 have been structurally characterized, and all are dimeric, with the general formula [M(NMe(2))(2)(µ-NSiR(3))](2), in which the µ(2)-NSiR(3) groups bridges two four-coordinate metal centers. The hafnium compound 3 possesses the same basic dimeric structure but shows additional incorporation of liberated HNMe(2) bonded to one metal. Compounds 11 and 12 are also both dimeric but also incorporate additional µ(2)-NMe(2) groups, which bridge Si and either Zr or Hf metal centers in the solid state. The Zr and Hf metal centers are both five-coordinated in these species. Aerosol-assisted CVD (AA-CVD) using 4-7 and 9-12 as precursors generates amorphous films containing M, N, Si, C, and O; the films are dominated by MO(2) with smaller contributions from MN, MC and MSiON based on XPS binding energies.

The effects of using ALD-grown ZnO buffer layers on the properties of indium tin oxide grown by chemical solution deposition.

In comparison to ITO films prepared by chemical solution deposition on bare substrates, the use of a ZnO buffer layer and Al2O3 barrier layer has been shown to have a significant effect on morphology, measured sheet resistance and therefore resistivity. In the case of quartz substrates, ITO resistivity decreased from 9.6 x 10(-3) ohms cm to 4.3 x 10(-3) ohms cm on incorporation of a ZnO buffer layer and Al2O3 barrier layer, both grown by ALD. A change in surface morphology was observed, due to the presence of the buffer layer, however, the ZnO buffer layer was not found to influence the XRD pattern of the ITO films.

Synthesis and structure of 6-aminofulvene-2-aldiminate complexes.

We report here a synthetic route to bis(N,N'-aryl)-6-aminofulvene-2-aldimine (AFA) ligand systems, specifically Ph(2)-AFAH and Dip(2)-AFAH. The synthesis and structural characterization of a series of Cu(I) complexes [(Ph(2)-AFA)Cu(CNPh)(2)] (2), [(Ph(2)-AFA)Cu(CN(i)Pr)] (3), and [(Dip(2)-AFA)Cu(CN(i)Pr)] (4), from the reaction of the corresponding lithiated AFA systems with Cu-Cl derivatives are reported; notably in the case of [(Ph(2)-AFA)Cu(CNPh)(2)] studies have revealed the existence of two structural isomers (2a and 2b), both of which can be isolated and structurally characterized. Density functional theory (DFT) calculations suggest that the two crystal forms are comparatively close in energy, and geometry optimization reveals a convergence of these two forms to a geometry that more closely resembles the solid-state structure of isomer 2b, having a CH···π interaction. The reactions of the AFA compounds Ph(2)-AFAH and Dip(2)-AFAH with ZnMe(2) and AlMe(3) have also been investigated, and the results of these reactions are described here.

Unprecedented double migratory insertion of phenyl isocyanide into cyclopentadienyl C-H bonds.

The reaction of [(eta(5)-C(5)H(5))Cu(CNPh)] with phenyl-isocyanide results in an unprecedented double migratory insertion into two sp(2) C-H bonds of a eta(5)-coordinated cyclopentadienyl group, and formation of the 6-aminofulvene-2-aldimine complexes [(CNPh)Cu{kappa(2)-N,N-C(5)H(3)-1,2-(CHNPh)(2)}] and [(CNPh)(2)Cu{kappa(2)-N,N-C(5)H(3)-1,2-(CHNPh)(2)}], respectively, both of which have been structurally characterised.

Topical antimicrobials in the control of wound bioburden.

Bacterial colonization and infection are important factors in compromised wound healing, particularly in chronic wounds. Although "best practice" for controlling these factors currently is not defined, systemic antibiotics are generally accepted as the preferred choice for treating infection, provided ischemia does not reduce their bioavailability. However, widespread use of systemic and topical antibiotics is associated with the emergence of resistant bacterial strains such as methicillin-resistant Staphylococcus aureus. Colonization of wounds presents a double problem--potentially delayed healing and a potential source for cross-contamination. The judicious use of dressings, notably those containing certain antiseptic agents, can be a valuable option to control infection and promote healing. A review of the literature underscores the importance of considering the antiseptic route as part of a concerted approach to wound management and infection control.

Disposable cleansing wipes.

With hospital cleanliness becoming a major issue over recent months, a great many campaigns are under way to improve cleaning levels in our hospitals. This article looks at the role of disposable wipes, both for patient skin hygiene and for hard-surface cleaning and disinfection, in keeping clinical areas clean and safe for patients.

The wound infection continuum and its application to clinical practice.

Four basic conditions exist in open wounds resulting from the level of bioburden present (bacterial contamination--normal but short-lived state, colonization--normal state, critical colonization--abnormal state, and infection--abnormal state). The two abnormal states have the potential to disrupt the orderly healing sequence, which results in the development of a chronic wound. In addition, the impact of the wound s anatomical position, duration, shape, or presentation; the patient s level of health and control of underlying pathologies; the presence of infection-potentiating factors such as foreign bodies, hematoma, and necrotic tissue; the sources and frequency of exogenous contamination; the considered virulence of the individual micro-flora species; and the potential synergism between different species all require consideration. This article discusses the states of bioburden and other aspects of microbiology relating to wound infection and their application to clinical practice.

Audit of wound swab sampling: why protocols could improve practice.

Many nurses carry out wound sampling using a surface swab, to establish infection levels and determine treatment. But reliability can be compromised by a number of factors. This paper examines reasons for sampling and its limitations. It describes how an audit of secondary and primary care nurses revealed wide variations in practice, and proposes protocols to improve care.