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The study of the initial radial deformations influence on the residual strained state components distribution through the hardened layer thickness under various types of surface hardening has been conducted. Chemical thermal machining (CTM) and shot blasting (SB) have been examined on the example of smooth solid steel cylindrical specimens with diameters D=10 mm and D=25 mm under a linear distribution of initial deformations through the hardened layer thickness (the maximum value is on the surface and zero on the maximum depth of hardening). The calculation has been conducted with use of the program complex PATRAN/NASTRAN. The solution has been carried out in axial symmetric positing by thermo elasticity method. On study results its been stated that the radial stresses through the hardened layer thickness under CTM and SB are positive. Incidentally the radial component of initial deformations under chemical thermal machining and shot blasting doesnt exercise essential influence on the radial and axial residual stresses distribution through the hardened layer thickness. Hence the initial radial deformations havent much significance at the evaluation of the residual strained stress state influence on the hardened parts endurance limit increment calculated by the average integral residual stresses criterion.

In all domains of life, the nucleobases of tRNA can be methylated. These methylations are introduced either by enzymes or by the reaction of methylating agents with the nucleophilic centers of the nucleobases. Herein, we present a systematic approach to identify the methylation sites within RNA in vitro and in vivo. For discrimination between enzymatic tRNA methylation and tRNA methylation damage in bacteria, we used nucleic acid isotope labeling coupled mass spectrometry (NAIL‐MS). With NAIL‐MS, we clearly observed the formation of 7‐methylguanosine, 3‐methyluridine, and 6‐methyladenosine during exposure of bacteria to the alkylating agent methyl methanesulfonate (MMS) in vivo. These damage products were not reported to form in tRNA in vivo, as they were masked by the enzymatically formed modified nucleosides in previous studies. In addition, we found formation of the known damage products 1‐methyladenosine and 3‐methylcytidine in vivo. With a dynamic NAIL‐MS setup, we observed tRNA repair by demethylation of these two RNA modifications in vivo. Furthermore, we saw the potential repair of 6‐methyladenosine but not 7‐methylguanosine in bacterial tRNA.

The thumb's radial collateral ligament (RCL) plays an important role in stabilizing the first metacarpophalangeal joint (MCP-1). RCL injuries are rare and treatment recommendations are inconsistent in the current literature. The aim of this study was to report on long-term outcomes following surgical repair of thumb RCL tear and to identify prognostic risk factors for treatment failure.Patients with RCL tear from 10/1998 to 10/2019 were included in the present retrospective single center cohort study. In follow-up visits, participants were assessed regarding pain, range of motion and strength as well as with disability of shoulder, arm and hands (DASH), and the Short-Form 36 (SF36) questionnaires. Finally, predictive factors of postoperative deficits were identified.43 patients fulfilled inclusion criteria. Median age was 43.5 years (range 18-80 years). The most frequent mechanism of injury was a fall or impact. Bony avulsions were identified in 46.5% (20/43). Time from injury to surgery was 12 days (0-276 days). One Stener-like lesion was observed intraoperatively among our patients. After surgical repair, the MCP-1 joint was stable in every patient. Mean time to follow-up was 5.3 years (1 month to 17 years). Persistency of pain in the MCP-1 joint was reported by 11 patients. Postoperative averaged score was 3.75 on DASH and 44.96 on SF36, respectively. The average grip and pinch strength was 32.7 kg and 8.37 kg, respectively. Predictive factors of postoperative deficits were delay of surgery of 3 weeks (OR 10.72, p 0.017) and palmar subluxation prior to surgery (OR 8.86, p 0.019).Long-term follow-up has proven that surgical repair of RCL enables the patient to regain adequate stability and strength of the MCP-1 joint and minimizes disability. Predictive risk factors of pain persistency after surgery are surgical delay and palmar subluxation of the MCP-1 joint.

The incidence of hearing impairment (HI) is higher in low- and middle-income countries when compared to high-income countries. There is therefore a necessity to estimate the burden of this condition in developing world. The aim of our study was to use a systematic approach to provide summarized data on the prevalence, etiologies, clinical patterns and genetics of HI in Cameroon. We searched PubMed, Scopus, African Journals Online, AFROLIB and African Index Medicus to identify relevant studies on HI in Cameroon, published from inception to 31 October, 2019, with no language restrictions. Reference lists of included studies were also scrutinized, and data were summarized narratively. This study is registered with PROSPERO, number CRD42019142788. We screened 333 records, of which 17 studies were finally included in the review. The prevalence of HI in Cameroon ranges from 0.9% to 3.6% in population-based studies and increases with age. Environmental factors contribute to 52.6% to 62.2% of HI cases, with meningitis, impacted wax and age-related disorder being the most common ones. Hereditary HI comprises 0.8% to 14.8% of all cases. In 32.6% to 37% of HI cases, the origin remains unknown. Non-syndromic hearing impairment (NSHI) is the most frequent clinical entity and accounts for 86.1% to 92.5% of cases of HI of genetic origin. Waardenburg and Usher syndromes account for 50% to 57.14% and 8.9% to 42.9% of genetic syndromic cases, respectively. No pathogenic mutation was described in GJB6 gene, and the prevalence of pathogenic mutations in GJB2 gene ranged from 0% to 0.5%. The prevalence of pathogenic mutations in other known NSHI genes was

The studies have established a number of causes of birch stand dieback in the Zhytomyr Polissya of Ukraine. Attention is focused on the deep pathology of the birch, caused by a complex of factors and, first of all, associated with bacterial etiology. It is established that the wetwood in the trunk of birch trees is of bacterial origin. The samples of wood and exudate have been selected for laboratory studies of plants, which had pronounced signs of pathology (cracks, swelling). It has been experimentally proven that the causative agent of birch dieback is the phytopathogenic bacteria Enterobacter nimipressuralis Carter, which causes dropsy of coniferous and deciduous forest trees. It has been established that the symptoms of bacterial dropsy are directly related to the saturation of the moisture of the tissues of the trunk and the shoots of the birch, the formation of the wet pathological nucleus in the plant, the cracks and ulcers on the trunks, the periderm during the active phase of the disease, necrotic wet ulcers in the places of external penetration of the infection, abundant fluxes exudate in the affected trees on the trunks are formed numerous water shoots. It was observed that in some mature birches the pathological core never came out with sapwood in the form of a crack, remaining inside the trunk during the whole ontogenesis. The plant's vitality was ensured by the activity of the last year's annual layers of wood and cambium, which were not affected by bacterial dropsy and annually set aside annual radial growth. This testified to the deep pathology of birch. It has been established that the composition of stand somewhat affects the dieback of birch trees. Complex and mixed tree stands are more resistant to bacteriosis. The prevalence of bacterial dropsy in birch stands of different age groups increases with their age and decrease in fullness. The unequal level of bacterial dropsy of various groups of plant associations was noted: blueberry, cereal, green-moss and heather. When examining the trunks of model trees, a pattern of altitude location of lesions was discovered. The data on the type of lesion and the density of wounds on the trunk are given, the species composition and the level of dominance of tremex, which are ecologically and trophically associated with birch, are analysed . Tremex are carriers of the causative agent of bacterial dropsy. Moreover, they are the source of accumulation and an important vector of inoculum spread in birch stands. It is also important that the pathogen is biologically inert to xylophagous insects.

The kinetics and mechanism of the formation of subvalent cadmium complexes in the Cdo – CdCl2 – ZnCl2 – NH4Cl system were studied spectroscopicaly. The results indicate that metallic cadmium reacts with Cd2 2+ and Cd2 3+ complex cations. The formation of Cd2 2+ and Cd2 3+ is evidenced by the absorption bands around 270 and 335 nm, respectively, in the electronic spectrum of the melt. The variation of the intensity of absorption bands during the reaction between Cd2+ and metallic cadmium was used to evaluate the kinetics of Cd2 2+ and Cd2 3+ formation. The rate constants for the formation of Cd2 2+ and Cd2 3+ complex cations evaluated from the slop of plot of lg(Ao - A∞) versus time are 4.22∙10-3 and 3.50∙10-3 s-1 , respectively. The effect of the electrolysis conditions on the rate of cadmium exchange between the electrodes was examined. The anode current efficiency of cadmium dissolution was found to increase with current density and temperature and to exceed the theoretically predicted value, which was attributed to the formation of subvalent cadmium compounds. The present results may be helpful in assessing parameters of cadmium electrorefining. A method was proposed for electrolytic Cd refining in which electrolysis is performed in molten cadmium chloride containing Cd in lower oxidation states. The technique for the preparation of the electrolyte was described. To prevent impurity transfer from the anode to cathode, bipolar Cd electrodes were used. The distribution ratios evaluated for typical metallic impurities in Cd show that high-purity Cd can be obtained in a single electrolysis cycle.

We exploit the degree of discretion embedded in the World Bank-IMF Debt Sustainability Framework (DSF) to understand the decision-making process of international financial institutions. The unique, internal dataset we use covers the universe of debt sustainability analyses conducted between December 2006 and January 2015 for low-income countries. These data allow us to identify cases where the risk rating implied by the application of the DSF's mechanical rules was overridden to assign a different official rating. Our results show that both political interests and bureaucratic incentives influence the decision to intervene in the mechanical decision-making process. Countries that are politically aligned with the institutions' major shareholders are more likely to receive an improved rating; especially in election years and when the mechanical assessment is not clear-cut. These results suggest that the room for discretion international financial institutions have can be a channel for informal governance and a source of biased decision-making.

Background: There is a huge gap in the audiological care in Africa by comparison with Western countries. Its main reason is the prohibitive cost of the medical devices used to screen or diagnose patients. A Cameroonian team tackled this problem by developing a medical device (SON’OR©) which integrates a new instrumentation amplifier structure dedicated to perform otoacoustic emissions (OAE) and brainstem evoked response audiometry (BERA). The major technical challenges to perform OAE and BERA are the synchronization and the amplification of signals of very low amplitude. In this work, we emphasize on the general criteria necessary and indispensable to achieve an optimal amplification. The application of a novel instrumentation amplifier structure characterized by its optimized noise factor in the case of BERA and OEA emissions provides simulations and experimental results fully in line with forecasts. The design of SON’OR© is based on general techniques of electronic instrumentation to which we associated the new instrumentation amplifier structure. Objective: To report the clinical evaluation of SON’OR© as a screening and diagnostic tool. Methods: We conducted a cross sectional comparative study in Centre Hospitalier d’Essos in Yaounde. We tested SON’OR© on two sets of subjects, one for OAE with OTODYNAMICS Echoport ILO 292-II as gold standard and the other for BERA with NEUROSOFT NEURO AUDIO© as gold standard. Each patient was tested with both devices and then we studied the inter device differences and calculated the sensitivity, specificity, positive predictive value and negative predictive value for each test. Results: We got 52 subjects for OEA and 51 for BERA testing. Sex ratio was 1 woman for 2 men in both groups. Mean age was 24.86(SD = 10.53) and 26.33 (10.55) for OAE and BERA groups respectively. SON’OR© had good performances, showing sensitivity of 92.85%/95%, specificity of 96.77%/90.47%, positive predictive value of 95.21%/93.44% and negative predictive value of 95.23%/92.68% for OAE/ BERA respectively. Conclusion: SON’OR© has good characteristics as a medical diagnostic tool. Furthermore its stability and performances in poor electrical conditions make it a robust device really suited for resource limited settings.

This study aimed to investigate GJB2 (connexin 26) and GJB6 (connexin 30) mutations associated with familial non-syndromic childhood hearing impairment (HI) in Cameroon. We selected only families segregating HI, with at least two affected individuals and with strong evidence of non-environmental causes. DNA was extracted from peripheral blood, and the entire coding region of GJB2 was interrogated using Sanger sequencing. Multiplex PCR and Sanger sequencing were used to analyze the prevalence of the GJB6-D3S1830 deletion. A total of 93 patients, belonging to 41 families, were included in the analysis. Hearing impairment was sensorineural in 51 out of 54 (94.4%) patients. Pedigree analysis suggested autosomal recessive inheritance in 85.4% (35/41) of families. Hearing impairment was inherited in an autosomal dominant and mitochondrial mode in 12.2% (5/41) and 2.4% (1/41) of families, respectively. Most HI participants were non-syndromic (92.5%, 86/93). Four patients from two families presented with type 2 Waardenburg syndrome, and three cases of type 2 Usher syndrome were identified in one family. No GJB2 mutations were found in any of the 29 families with non-syndromic HI. Additionally, the GJB6-D3S1830 deletion was not identified in any of the HI patients. This study confirms that mutations in the GJB2 gene and the del(GJB6-D13S1830) mutation do not contribute to familial HI in Cameroon.

The chapter reviews the literature on the political economy of international organizations (IOs). Considering IOs as products of the preferences of various actors rather than monolithic entities, the authors focus on national politicians, international bureaucrats, interest groups, and voters. By looking into the details of decision-making in IOs, the literature shows that a focus on states as the prime actors in IOs overlooks important facets of the empirical reality. Mainly focusing on empirical research, the authors discuss the four main actors involved and examine how they influence, use, and shape IOs. They find that IO behavior often reflects the interests of politicians, bureaucrats, and interest groups, while the impact of voters is limited. The final section reviews proposals for reforms addressing this weak representation of voter preferences.

Much of the International Finance Corporation's (IFC) lending benefits private companies from rich countries and supports projects in middle-income countries. Large corporations such as Lidl or Movenpick have received its loans for highly profitable investments. This contrasts to some extent with the IFC's official mandate, which is to finance poverty-reducing projects for which private capital is not available on reasonable terms. Investigating a potential driver of this mismatch, we argue that some governments can influence the allocation of IFC loans to the benefit of private companies in their countries. Using new data for more than 3000 IFC projects over the 1995–2015 period we show that (joint) IFC Board membership of countries where borrowing companies are based and of countries where the projects are implemented increases the likelihood that these countries receive IFC loans. This has implications for the debate on leveraging private-sector investments for development.