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Single giant unilamellar vesicles (GUVs) rupture spontaneously from their salt-laden suspension onto solid surfaces. At hydrophobic surfaces, the GUVs rupture via a recurrent, bouncing ball rhythm. During each contact, the GUVs, rendered tense by the substrate interactions, porate, and spread a molecularly transformed motif of a monomolecular layer on the hydrophobic surface from the point of contact in a symmetric manner. The competition from pore closure, however, limits the spreading and produces a daughter vesicle, which re-engages with the substrate. At solid hydrophilic surfaces, by contrast, GUVs rupture via a distinctly different recurrent burst-heal dynamics; during burst, single pores nucleate at the contact boundary of the adhering vesicles, facilitating asymmetric spreading and producing a "heart"-shaped membrane patch. During the healing phase, the competing pore closure produces a daughter vesicle. In both cases, the pattern of burst-reseal events repeats multiple times, splashing and spreading the vesicular fragments as bilayer patches at the solid surface in a pulsatory manner. These remarkable recurrent dynamics arise, not because of the elastic properties of the solid surface, but because the competition between membrane spreading and pore healing, prompted by the surface-energy-dependent adhesion, determine the course of the topological transition.

This paper makes a contribution to the literature on the relationship between undernourishment and ICT. There are very few studies on this topic, and existing studies have not yet looked at the channels through which ICT affect undernourishment. We use a stochastic impact model extended to the population, affluence, and technology (STIRPAT) regression model to estimate both the effect and transmission of ICT on undernourishment in 45 African countries from 2000 to 2017. The empirical results show that ICT use measured by internet and mobile phone penetration reduces malnutrition. Furthermore, the mediation analysis reveals that ICT not only have a direct positive effect on undernourishment but also a positive indirect effect through their impact on per capita income, education, health, and access to clean water. However, the total effect is positive and indicates that ICT are useful in reducing undernourishment in Africa. In addition, these results have also shown us that variables such as education, public spending on health and access to drinking water are useful in reducing malnutrition in Africa. However, per capita income and the level of inflation exacerbate malnutrition on the continent. To enhance the beneficial effects of ICT on malnutrition, governments should design policies to improve access to water, education, and health care; better distribution of national wealth.

Background: Fruits and vegetables are very important for human diet as they provide all the nutrients needed to be healthy with just a daily-recommended intake of 400 to 600 mg. However, they constitute one of the major sources of human infectious agents. Thus monitoring of the microbial contaminants of the fruits and vegetables is very crucial for human safety. Method: A cross sectional study was conducted on fruits and vegetables in four markets (Mfoundi, Mokolo, Huitième and Acacia) of the Yaoundé city from October 2020 to March 2021. In all, 528 samples were purchased (carrots, cucumbers, cabbages, lettuces, leeks, green beans, okra, celeries, pepper, green peppers and tomatoes) and processed for infective agents using the centrifugation methods (Formalin, distilled and saline water). Seventy-four (74) soil/water samples collected from the sale environment were analysed using the same technics. Results: Overall, 149/528 (28.21%) were contaminated by at least one infective agent: 130 (24.62%) and 19 (3.6%) having one and two pathogen species respectively. Vegetables had high contamination rate (22.34%) than fruits (5.87%). Lettuce (52.08%), carrot (41.66%) and cabbage (35.41%), were the most contaminated while okra was the least (6.25%). Candida spp. (14.01%) and larva of Strongyloides stercoralis (7.76%) were more observed while Hookworms (1.13%) was the least. Frequency of Strongyloides stercoralis (p = 0.001) and Candida spp. (p = 0.01) were statistically high than other pathogens. Contamination rates were similar for washed (27.65%) and unwashed (28.78%) samples before sale. Candida spp. (p = 0.001), Strongyloides stercoralis (p = 0.01) and Entamoeba histolytica/dispar (p = 0.017) showed significant contamination rates by month. Contamination trends were high in the rainy season (42.6%) than the dry season (15.1%). Correlation between environment and products sold revealed same pathogens in both cases. Conclusion: The study highlights that the sale environment and products constitute potential source of microbial contamination. These data raised the concern of stakeholders about health risk related to vegetables and fruits sold in some local markets in Cameroon. Thus the necessity for them to development more appropriate policies on the surveillance of sale environment and on the management of these products during the different process phases by the population.

This paper examines the role of corruption in the relationship between natural resources and exports diversification 1980–2020) through the bound test of co-integration and the Fully Modified Ordinary Least Square (FMOLS). The main findings reveal that, natural resource accentuates export diversification. However, in the long run, oil resources accentuate export diversification while forest and mineral resources decrease export diversification. Also, in the short run, executive corruption accentuates with no limit, the concentration effect of natural resources on export diversification. While in the long run, executive corruption instead mitigates the negative effect of natural resources irrespective of their type on export diversification. Natural resources curse export diversification if the executive corruption is below certain thresholds. These findings imply that in the Cameroonian context of cumbersome and bureaucratic regulations, the cost of corruption is lesser than cost the of administrative bottlenecks, leading to the corollary that corruption may favors export diversification when production and export processes present barriers that exceed a certain threshold. Cameroon authorities should therefore curb these cumbersome and bureaucratic procedures that are costly and that harm export diversification.

Abstract Background The incidence of schistosomiasis‐induced male reproductive dysfunction and infertility is probably underestimated compared to female genital schistosomiasis. This study aimed to investigate the impact of Schistosoma haematobium or S. mansoni infection on the reproductive function of men of reproductive age in Tibati and Wouldé, two endemic schistosomiasis areas in the Adamawa region of Cameroon. Methods A total of 89 men of reproductive age (range 14–56 years) from two localities were enrolled in the study, with 51 in Tibati and 38 in Wouldé. Each participant was submitted to a questionnaire to document data on sociodemographic and stream contact behaviors. A medical examination was performed to measure the testes’ circumference and evaluate genital tract pathologies. Stool and urine samples were collected and screened for the presence of S. haematobium or S. mansoni ova. Blood serum was used to assess the levels of transaminases and testosterone. Results Schistosoma haematobium was present only in Tibati, with a prevalence of 31.37%. The S. mansoni prevalence was 3.92% at Tibati and 44.71% at Wouldé. The intensity of infection was 22.12 ± 9.57 eggs/10 mL for S. haematobium and 128.10 ± 3.76 epg for S. mansoni. Serum transaminase activity and the mean testicular circumference of Schistosoma-positive individuals were close to Schistosoma-negative individuals. However, the testes size was more prominent in S. mansoni-positive individuals than in S. haematobium-positive individuals (P

Abstract 2D metal–organic frameworks have been recently proposed as a flexible platform for realizing new functional materials including quantum phases. Here, we present a method to create metal‐organic dimer complexes by on‐surface assembly on a metal substrate using low‐temperature scanning tunneling microscopy (STM) and spectroscopy (STS). We demonstrate that a dimer of Mn‐Phthalocyanine (MnPc)2 on a Ag(111) surface can be switched between two stable configurations upon a small conformational change controlled by STM manipulation. By means of density‐functional theory calculations, it is found that the two conformations correspond to an antiferromagnetic (AFM) and a ferromagnetic (FM) state respectively. Directly coordinated Mn atoms of the dimer lead to an AFM‐coupling whereas indirectly coordinated (shifted) Mn atoms lead to a FM‐coupling. Rarely seen in a molecular‐dimers with transition‐metal atoms, the FM‐AFM‐FM transition is thus readily on‐surface accessible. Furthermore, the two configurations of the switch are easily identified by their Kondo states, opening interesting routes in terms of both, writing (FM versus AFM states) and reading. These results pave the experimental route toward dimer‐based materials with complex magnetic structures of potential interest for application in spintronics, logics and computing.

IntroductionThis study aimed to establish pre-/post Coronavirus Disease 2019 (COVID-19) diagnosis/treatment symptoms, ownership/utilisation of face masks (FMs), as well as vaccine hesitancy (VH) amongst patients recovering from COVID-19.MethodsA cross-sectional survey was conducted from April - October 2021. Data was collected with structured self-administered questionnaires. Multinomial regression was used to determine associations between ownership/utilisation of FMs with respondents' characteristics.ResultsUnproductive cough and fatigue were prevalent before and after treatment. Pre-/Post COVID-19 symptoms severity ranged from mild to moderate. There was a COVID-19 VH rate of 492 (74%). The prevalence of FM ownership and utilisation were, respectively, 613 (92.2%) and 271 (40.8%). One main factor was associated with FM ownership; respondent's sex (p; 5.5x10-2, OR; 0.5, 95%C.I; 0.3 - 1.0). The main reasons for irregular utilisation were; inability to be consistent, only used outdoors, and boredom.ConclusionThe treatment of COVID-19 does not mean immediate recovery as mild to moderate grade severity still persists. Face mask availability and ownership does not mean appreciable utilisation. This study advocates for an intensification of COVID-19 preventive practices, as well as elaborate education on the importance of vaccination.

The lipidome of plant plasma membranes-enriched in cellular phospholipids containing at least one polyunsaturated fatty acid tail and a variety of phytosterols and phytosphingolipids-is adapted to significant abiotic stresses. But how mesoscale membrane properties of these membranes such as permeability and deformability, which arise from their unique molecular compositions and corresponding lateral organization, facilitate response to global mechanical stresses is largely unknown. Here, using giant vesicles reconstituting mixtures of polyunsaturated lipids (soy phosphatidylcholine), glucosylceramide, and sitosterol common to plant membranes, we find that the membranes adopt "janus-like" domain morphologies and display anomalous solute permeabilities. The former textures the membrane with a single sterol-glucosylceramide-enriched, liquid-ordered domain separated from a liquid-disordered phase consisting primarily of soy phosphatidylcholine. When subject to osmotic downshifts, the giant unilamellar vesicles (GUVs) respond by transiently producing well-known swell-burst cycles. In each cycle, the influx of water swells the GUV, rendering the membrane tense. Subsequent rupture of the membrane through transient poration, which localizes in the liquid-disordered phase or at the domain boundaries, reduces the osmotic stress by expelling some of the excess osmolytes (and solvent) before sealing. When subject to abrupt hypertonic stress, they deform by nucleating buds at the domain phase boundaries. Remarkably, this incipient vesiculation is reversed in a statistically significant fraction of GUVs because of the interplay with solute permeation timescales, which render osmotic stresses short-lived. This, then, suggests a novel control mechanism in which an interplay of permeability and deformability regulates osmotically induced membrane deformation and limits vesiculation-induced loss of membrane material. Interestingly, recapitulation of such dynamic morphological reconfigurability-switching between budded and nonbudded morphologies-due to the interplay of membrane permeability, which temporally reverses the osmotic gradient, and domain boundaries, which select modes of deformations, might prove valuable in endowing synthetic cells with novel morphological responsiveness.

Burkina Faso like many other African countries hosts many renewable energy (RE) and energy efficiency (EE) projects that are not registered to the clean development mechanism (CDM), but which could represent potential CDM opportunities. This study seeks to determine these projects’ impact on the level of CO2 emissions in the country, and to determine their CDM potential by quantifying their carbon emissions reduction, using approved CDM methodologies adapted to the projects. 21 RE projects and 7 EE projects were considered, and all proven to be additional. Results revealed that, 68709.424 MWh and 9430.446MWh were saved and displaced by the EE and RE projects respectively annually, accounting for 48157.668 tCO2e emissions reduced annually. This accounts for a 63.12% emissions reduction from the baseline scenario and represents a huge potential for the CDM, ready to be harnessed. The total amount of emissions reduced could generate about 48157.668 Certified Emissions Reduction (CERs) yearly. Considering a carbon price of $10/tCO2e and a 10-year fixed crediting period starting from 2020 would imply a total revenue of $4815766.8 in 2030 from the CERs , which will increase the sector’s attractiveness to investors. Policies promoting the registration of these projects to the CDM are essential to boost the development of more of such projects in the country/ region, which will benefit from the sustainable development the CDM offers, while contributing to the achievement of its Intended Nationally Determined Contributions.

The goal of this pilot study was to determine whether HDL glycoprotein composition affects HDL's immunomodulatory function. HDL were purified from healthy controls (n = 13), subjects with metabolic syndrome (MetS) (n = 13), and diabetic hemodialysis (HD) patients (n = 24). Concentrations of HDL-bound serum amyloid A (SAA), lipopolysaccharide binding protein (LBP), apolipoprotein A-I (ApoA-I), apolipoprotein C-III (ApoC-III), α-1-antitrypsin (A1AT), and α-2-HS-glycoprotein (A2HSG); and the site-specific glycovariations of ApoC-III, A1AT, and A2HSG were measured. Secretion of interleukin 6 (IL-6) in lipopolysaccharide-stimulated monocytes was used as a prototypical assay of HDL's immunomodulatory capacity. HDL from HD patients were enriched in SAA, LBP, ApoC-III, di-sialylated ApoC-III (ApoC-III2) and desialylated A2HSG. HDL that increased IL-6 secretion were enriched in ApoC-III, di-sialylated glycans at multiple A1AT glycosylation sites and desialylated A2HSG, and depleted in mono-sialylated ApoC-III (ApoC-III1). Subgroup analysis on HD patients who experienced an infectious hospitalization event within 60 days (HD+) (n = 12), vs. those with no event (HD-) (n = 12) showed that HDL from HD+ patients were enriched in SAA but had lower levels of sialylation across glycoproteins. Our results demonstrate that HDL glycoprotein composition, including the site-specific glycosylation, differentiate between clinical groups, correlate with HDL's immunomodulatory capacity, and may be predictive of HDL's ability to protect from infection.

Objective: The aim of this study was to assess the efficacy of lytic bacteriophages on Staphylococcus aureus causing bovine mastitis, by in vitro and in vivo assays using Galleria mellonella and murine mastitis models. Methods: Between May and December 2016, ten S. aureus (five methicillin-resistant and five methicillin-sensitive) isolates were isolated from milk samples of cattle with mastitis in Belgium and Norway. The isolates were assessed in vitro for their susceptibility to four lytic bacteriophages (Romulus, Remus, ISP and DSM105264) and subsequently in vivo in G. mellonella larvae and in murine mastitis model. Results: Romulus, Remus and ISP showed a lytic activity against the S. aureus isolates in vitro. A larvae survival rate below 50% was observed at 4 days post-inoculation (DPI) in the groups infected with a methicillin-sensitive S. aureus isolate and treated with these three phages in vivo. An incomplete recovery of the mouse mastitis was observed at 48 h post-inoculation (HPI) in the groups infected and treated with the ISP phage in vivo. Conclusions: The observations are much more pronounced statistically between the infected- phosphate buffered saline (PBS)-treated and infected-phage-treated groups in G. mellonella and the murine mastitis model demonstrating an effect of the phages against S. aureus associated with bovine mastitis.

To study the impact of lateral variation in surface topography on the microbial colonization of plant leaves, we used a two-step casting process to generate topomimetic “replicasts” in polydimethylsiloxane which faithfully resembled leaf surface topography at submicrometer scale. This process revealed that the shape and size of the phyllotelma—the collective body of standing water on a leaf surface—was a function of wetting method and presence of surface features, in particular leaf veins. The use of dyes and fluorescently labeled bacteria showed that these veins, especially on the abaxial side, contributed to the pooling, retention, and lateral spread of water and microorganisms. Bodies of water along veins acted as conduits that allowed bacterial cells to sense chemicals over distances exceeding their body length by four orders of magnitude. Bacterial survival rates under conditions of low relative humidity were twice as high on leaf replicasts as on flat surfaces, suggesting topography-dependent protection from desiccation. Our findings highlight the need for greater quantitative understanding of the impact of leaf surface topography on phyllotelma connectivity and the outcomes of interactions between microorganisms and with their plant host. Such understanding benefits both theory and practice of phyllosphere microbiology in areas such as foliar disease management and food safety of leafy greens.

The activation of microglia and the infiltration of macrophages are hallmarks of neuroinflammation after acute brain injuries, including traumatic brain injury (TBI). The two myeloid populations share many features in the post-injury inflammatory response, thus, being antigenically indistinguishable. Recently Tmem119, a type I transmembrane protein specifically expressed by microglia under physiological conditions, was proposed as a tool to differentiate resident microglia from blood-borne macrophages, not expressing it. However, the validity of Tmem119 as a specific marker of resident microglia in the context of acute brain injury, where microglia are activated and macrophages are recruited, needs validation. Our purpose was to investigate Tmem119 expression and distribution in relation to the morphology of brain myeloid cells present in the injured area after TBI. Mice underwent sham surgery or TBI by controlled cortical impact (CCI). Brains from sham-operated, or TBI mice, were analyzed by in situ hybridization to identify the cells expressing Tmem119, and by Western blot and quantitative immunofluorescence to measure Tmem119 protein levels in the entire brain regions and single cells. The morphology of Iba1+ myeloid cells was analyzed at different times (4 and 7 days after TBI) and several distances from the contused edge in order to associate Tmem119 expression with morphological evolution of active microglia. In situ hybridization indicated an increased Tmem119 RNA along with increased microglial complement C1q activation in the contused area and surrounding regions. On the contrary, the biochemical evaluation showed a drop in Tmem119 protein levels in the same areas. The Tmem119 immunoreactivity decreased in Iba1+ myeloid cells found in the contused cortex at both time points, with the cells showing the hypertrophic ameboid morphology having no Tmem119 expression. The Tmem119 was present on ramifications of resident microglia and its presence was decreased as a consequence of microglial activation in cortical areas close to contusion. Based on the data, we conclude that the decrease of Tmem119 in reactive microglia may depend on the process of microglial activation, which involves the retracting of their branchings to acquire an ameboid shape. The Tmem119 immunoreactivity decreases in reactive microglia to similar levels than the blood-borne macrophages, thus, failing to discriminate the two myeloid populations after TBI.

Staphylococci are among the commonly isolated bacteria from intramammary infections in bovines, where Staphylococcus aureus is the most studied species. This species carries a variety of virulence genes, contributing to bacterial survival and spread. Less is known about non-aureus staphylococci (NAS) and their range of virulence genes and mechanisms, but they are the most frequently isolated bacteria from bovine milk. Staphylococci can also carry a range of antimicrobial resistance genes, complicating treatment of the infections they cause. We used Illumina sequencing to whole genome sequence 93 staphylococcal isolates selected from a collection of staphylococcal isolates; 45 S. aureus isolates and 48 NAS isolates from 16 different species, determining their content of antimicrobial resistance genes and virulence genes. Antimicrobial resistance genes were frequently observed in the NAS species as a group compared to S. aureus. However, the lincosamide resistance gene lnuA and penicillin resistance gene blaZ were frequently identified in NAS, as well as a small number of S. aureus. The erm genes conferring macrolide resistance were also identified in several NAS isolates and in a small number of S. aureus isolates. In most S. aureus isolates, no antimicrobial resistance genes were detected, but in five S. aureus isolates three to six resistance genes were identified and all five of these carried the mecA gene. Virulence genes were more frequently identified in S. aureus, which contained on average five times more virulence genes compared to NAS. Among the NAS species there were also differences in content of virulence genes, such as S. chromogenes with a higher average number of virulence genes. By determining the content of a large selection of virulence genes and antimicrobial resistance genes in S. aureus and 16 different NAS species our results contribute with knowledge regarding the genetic basis for virulence and antimicrobial resistance in bovine staphylococci, especially the less studied NAS. The results can create a broader basis for further research into the virulence mechanisms of this important group of bacteria in bovine intramammary infections.

A central tenet of signal transduction in eukaryotic cells is that extra-cellular ligands activate specific cell surface receptors, which orchestrate downstream responses. This ''protein-centric" view is increasingly challenged by evidence for the involvement of specialized membrane domains in signal transduction. Here, we propose that membrane perturbation may serve as an alternative mechanism to activate a conserved cell-death program in cancer cells. This view emerges from the extraordinary manner in which HAMLET (Human Alpha-lactalbumin Made LEthal to Tumor cells) kills a wide range of tumor cells in vitro and demonstrates therapeutic efficacy and selectivity in cancer models and clinical studies. We identify a ''receptor independent" transformation of vesicular motifs in model membranes, which is paralleled by gross remodeling of tumor cell membranes. Furthermore, we find that HAMLET accumulates within these de novo membrane conformations and define membrane blebs as cellular compartments for direct interactions of HAMLET with essential target proteins such as the Ras family of GTPases. Finally, we demonstrate lower sensitivity of healthy cell membranes to HAMLET challenge. These features suggest that HAMLET-induced curvature-dependent membrane conformations serve as surrogate receptors for initiating signal transduction cascades, ultimately leading to cell death.