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Over the centuries, paper has been made from a wide variety of materials. Today fiber comes mainly from two sources: wood and recycled paper products. Gnidia glauca bark was used in neighbouring Oku for local paper production. The properties of wood and bark of Gnidia glauca have been less explored in the literature. Therefore, in this study, the anatomical properties were investigated to evaluate the potential utilization of this species especially in pulp and paper production. Sections (transversal, tangential and radial) with a thickness of about 15-30µm were obtained from eight samples and contain phloem, cambial zone and secondary xylem. The sections were stained with 0.1% safranin O. to determine the fiber length and vessel element, we used maceration. Densities of vessels, cambial zone thickness, fiber wall thickness, fiber length were measured in bright-field microscopy images using AnalySIS Pro 3.2 software. The results show that our species contain short wood fiber (1.32 mm in average) while the fiber bark are longer. Gnidia wood fibers are the longest among Ailanthus altissima trunk fiber, wheat straw, canola stalks, cotton stalks and Aspen. Fiber diameter of bark is about twice of those of common papermaking and lumen width is the smallest. Cell wall thickness of Gnidia glauca fiber bark is thicker than those of Gnidia wood and non-wood fibers; consequently, the Runkel ratio is highest (7.35). The flexibility coefficient of Gnidia glauca xylem fibers is 54.51, so it is included in the elastic fibers group while phloem fibers is 12.15 and it is included in the highly rigid fiber. The results of anatomical study of Gnidia glauca show that its xylem fiber dimensions are in the normal range for hardwood and are suitable for paper manufacturing.

Background Vibrio cholerae is endemic in South Asia and Africa where outbreaks of cholera occur widely and are particularly associated with poverty and poor sanitation. Knowledge of the genetic diversity of toxigenic V. cholerae isolates, particularly in Africa, remains scarce. The constraints in improving this understanding is not only the lack of regular cholera disease surveillance, but also the lack of laboratory capabilities in endemic countries to preserve, store and ship isolates in a timely manner. We evaluated the use of simplified sample preservation methods for molecular characterization using multi-locus variable-number tandem-repeat analysis (MLVA) for differentiation of Vibrio cholerae genotypes. Methods and Findings Forty-seven V. cholerae isolates and 18 enriched clinical specimens (e.g. stool specimens after enrichment in broth) from cholera outbreaks in Cameroon were preserved on Whatman filter paper for DNA extraction. The samples were collected from two geographically distinct outbreaks in the Far North of Cameroon (FNC) in June 2014 and October 2014. In addition, a convenience sample of 14 isolates from the Philippines and 8 from Mozambique were analyzed. All 87 DNAs were successfully analyzed including 16 paired samples, one a cultured isolate and the other the enriched specimen from which the isolate was collected. Genotypic results were identical between 15 enriched specimens and their culture isolates and the other pair differed at single locus. Two closely related, but distinct clonal complexes were identified among the Cameroonian specimens from 2014. Conclusions Collecting V. cholerae using simplified laboratory methods in remote and low-resource settings allows for subsequent advanced molecular characterization of V. cholerae O1. These simplified DNA preservation methods identify V. cholerae and make possible timely information regarding the genetic diversity of V. cholerae; our results set the stage for continued molecular epidemiological research to better understand the transmission and dissemination of V. cholerae in Africa and elsewhere worldwide., Author Summary Cholera, caused by the bacterium Vibrio cholerae, causes an estimated 3–5 million cases every year and more than 100,000 deaths. The highest disease burden is reported from Africa, however, the epidemic potential and transmission patterns among circulating strains is scarcely understood. The challenges of disease surveillance are constrained by the costs associated with laboratory confirmation and sample preservation. To improve the ability to identify the cholera disease burden, to subsequently understand the molecular epidemiology of circulating cholera strains, and to elucidate transmission patterns, we applied simplified collection methodologies to facilitate timely molecular characterization of V. cholerae isolates from Cameroon, Mozambique and the Philippines. Enriched specimens as well as cultured isolates were examined, demonstrating that enriched specimens provide sufficient material for genetic analysis. The results of the genetic analyses did not suggest significant genetic diversity within two distinct outbreaks in Cameroon. The study detected a possible relationship between isolates present in Cameroon and two isolates from Mozambique, two geographically distant nations in Africa. Whole genome sequencing can test whether this hypothesis is correct. Our findings set the stage for surveillance and molecular characterization in these areas to elucidate more fully the relationship and disease transmission patterns.