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This study examines how F O F 1 -ATPase, hydrogenases (Hyd-1 and Hyd-2), and potassium transport systems (TrkA) interact to maintain the proton motive force (pmf) in E. coli during fermentation of different glucose concentrations (2 g L−1 and 8 g L−1). Our findings indicate that mutants lacking the hyaA-hyaC genes exhibited a 30 % increase in total proton flux compared to the wild type when grown with 2 g L−1 glucose. This has been observed during assays where similar glucose levels were supplemented. Disruptions in proton pumping, particularly in hyaB and hyaC single mutants, led to increased potassium uptake. The hyaB mutant showed a threefold increase in the contribution of F O F 1 -ATPase to proton flux, suggesting a significant role for Hyd-1 in proton translocation. In the hybC mutant grown in 2 g L−1 glucose conditions, DCCD-sensitive fluxes decreased by 70 %, indicating critical role of Hyd-2 in proton transport and F O F 1 function. When cells were grown with 8 g L−1 glucose, the 2H+/1K+ ratio was significantly disturbed in both wild type and mutants. Despite these perturbances, mutants with disruptions in Hyd-1 and Hyd-2 maintained constant F O F 1 function, suggesting that this enzyme remains stable in glucose-rich environments. These results provide valuable insights into how Hyd-1 and Hyd-2 contribute to the regulation of ion transport, particularly proton translocation, in response to glucose concentration. Our study uncovered potential complementary mechanisms between Hyd-1 and Hyd-2 subunits, suggesting a complex interplay between these enzymes via metabolic cross talk with F O F 1 in response to glucose concentrations to maintain pmf. [Display omitted] • Mutants lacking hyaA-hyaC genes exhibited increased proton flux under low glucose conditions. • Complementary mechanisms between Hyd-1 and Hyd-2 subunits were suggested, depending on glucose concentrations. • DCCD-sensitive fluxes decreased by 70 % in hybC single mutant. • High glucose concentration disturbed proton/potassium exchange ratio. [ABSTRACT FROM AUTHOR]

In this study, alternative uses for lignocellulosic waste by considering them a source of eco-friendly and renewable energy generation with the application of the anaerobic digestion of treated and untreated waste for biogas and biohydrogen generation were investigated. The diluted sulfuric acid method was used for both the substrates and inoculum. Hydrogen production was absent when untreated spent coffee grounds (SCG) and alcohol waste (AW) were both used with the inoculum at pH 5.5 and pH 7.5. Meanwhile, the highest biogas yield of 320 dm3 kg V.S−1 was obtained when using AW at pH 7.5, with a 190 dm3 kg V.S−1 yield of methane. Instead, hydrogen production was observed when initially 4% (w/v) and 6% (w/v) SCG-containing hydrolysates were used as the substrates at pH 5.5, yielding 2.9 ± 0.09 dm3 kg V.S−1 and 3.85 ± 0.12 dm3 kg V.S−1, respectively. The further optimization of pretreatment technologies and pH control could lead to increased and prolonged hydrogen production. [ABSTRACT FROM AUTHOR]

Escherichia coli anaerobically ferment glucose and perform proton/potassium exchange at pH 7.5. The role of hyf (hydrogenase 4) subunits (HyfBDF) in sensing different concentrations of glucose (2 g L−1 or 8 g L−1) via regulating H+/K+ exchange was studied. HyfB, HyfD and HyfF part of a protein family of NADH-ubiquinone oxidoreductase ND2, ND4 and ND5 subunits is predicted to operate as proton pump. Specific growth rate was optimal in wild type and mutants grown on 2 g L−1 glucose reaching ~ 0.8 h−1. It was shown that in wild type cells proton but not potassium fluxes were stimulated ~ 1.7 fold reaching up to 1.95 mmol/min when cells were grown in the presence of 8 g L−1 glucose. Interestingly, cells grown on peptone only had similar proton/potassium fluxes as grown on 2 g L−1glucose. H+/K+ fluxes of the cells grown on 2 g L−1 but not 8 g L−1 glucose depend on externally added glucose concentration in the assays. DCCD-sensitive H+ fluxes were tripled and K+ fluxes doubled in wild type cells grown on 8 g L−1 glucose compared to 2 g L−1 when in the assays 2 g L−1glucose was added. Interestingly, in hyfF mutant when cells were grown on 2 g L−1glucose and in 2 g L−1 assays DCCD-sensitive fluxes were not determined compared to wild type while in hyfD mutant it was doubled reaching up to 0.657 mmol/min. In hyf mutants DCCD-sensitive K+ fluxes were stimulated in hyfD and hyfF mutants compared to wild type but depend on external glucose concentration. DCCD-sensitive H+/K+ ratio was equal to ~ 2 except hyfF mutant grown and assayed on 2 g L−1glucose while in 8 g L−1 conditions role of hyfB and hyfD is considered. Taken together it can be concluded that Hyd-4 subunits (HyfBDF) play key role in sensing glucose concentration for regulation of DCCD-sensitive H+/K+ fluxes for maintaining proton motive force generation. [ABSTRACT FROM AUTHOR]

After brewing roasted coffee, spent coffee grounds (SCGs) are generated being one of the daily wastes emerging in dominant countries with high rate and big quantity. Escherichia coli BW25113 wild-type strain, mutants with defects in hydrogen (H2)-producing/oxidizing four hydrogenases (Hyd) (ΔhyaB ΔhybC, ΔhycE, ΔhyfG) and septuple mutant (ΔhyaB ΔhybC ΔhycA ΔfdoG ΔldhA ΔfrdC ΔaceE) were investigated by measuring change of external pH, bacterial growth and H2 production during the utilization of SCG hydrolysate. In wild type, H2 was produced with rate of 1.28 mL H2 (g sugar)−1 h−1 yielding 30.7 mL H2 (g sugar)−1 or 2.75 L (kg SCG)−1 during 24 h. In septuple mutant, H2 production yield was 72 mL H2 (g sugar)−1 with rate of 3 mL H2 (g sugar)−1 h−1. H2 generation was absent in hycE single mutant showing the main role of Hyd-3 in H2 production. During utilization of SCG wild type, specific growth rate was 0.72 ± 0.01 h−1 with biomass yield of 0.3 g L−1. Genetic modifications and control of external parameters during growth could lead to prolonged and enhanced microbiological H2 production by organic wastes, which will aid more efficiently global sustainable energy needs resulting in diversification of mobile and fixed energy sources. [ABSTRACT FROM AUTHOR]

Hydrogen (H 2)-producing hydrogenase (Hyd) activity of E. coli wild type and mutants with defects in subunits of Hyd-3 or Hyd-4 during fermentation at different glucose concentrations and pHs was studied. Hyd-3 was mainly responsible for H 2 production but a significant contribution by Hyd-4 to total H 2 production depended on the glucose concentration and pH. Surprisingly, not all Hyd-3 or Hyd-4 subunits contributed towards H 2 production. Hyd-4 mainly exhibited H 2 -oxidizing activity in cells growing on 0.2% glucose at pH 7.5, while at pH 5.5 it had a significant impact on H 2 production. Importantly, a hyfG mutant (lacking the large subunit of Hyd-4) had a ~2.2 fold decrease in H 2 production when cells were grown with 0.2% glucose. A similar role of Hyd-4 was shown at pH 6.5 grown with 0.8% glucose. This study provides new information to allow improvements in H 2 production yield and in our general understanding of H 2 metabolism. • At pH 7.5 Hyd-4 is working towards H 2 oxidation and proton translocation. • In hyfG mutant H 2 production at pH 5.5 was decreased ~2 fold. • Hyd-3 and Hyd-4 work towards H 2 production at pH 5.5 • Hyd-3 and Hyd-4 several subunits might interact forming big hydrogenase complex. [ABSTRACT FROM AUTHOR]

Pentameric FocA permeates either formate or formic acid bidirectionally across the cytoplasmic membrane of anaerobically growing Escherichia coli. Each protomer of FocA has its own hydrophobic pore, but it is unclear whether formate or neutral formic acid is translocated in vivo. Here, we measured total and dicyclohexylcarbodiimide (DCCD)-inhibited proton flux out of resting, fermentatively grown, stationary-phase E. coli cells in dependence on FocA. Using a wild-type strain synthesizing native FocA, it was shown that using glucose as a source of formate, DCCD-independent proton efflux was ∼2.5 mmol min−1, while a mutant lacking FocA showed only DCCD-inhibited, F O F 1 -ATPase-dependent proton-efflux. A strain synthesizing a chromosomally-encoded FocA H209N variant that functions exclusively to translocate formic acid out of the cell, showed a further 20 % increase in FocA-dependent proton efflux relative to the parental strain. Cells synthesizing a FocA T91A variant, which is unable to translocate formic acid out of the cell, showed only DCCD-inhibited proton efflux. When exogenous formate was added, formic acid uptake was shown to be both FocA- and proton motive force-dependent. By measuring rates of H 2 production, potassium ion flux and ATPase activity, these data support a role for coupling between formate, proton and K+ ion translocation in maintaining pH and ion gradient homeostasis during fermentation. FocA thus plays a key role in maintaining this homeostatic balance in fermenting cells by bidirectionally translocating formic acid. • FocA bidirectionally translocates formate plus a proton across the membrane. • Coupling between ion translocation activities of FocA, F O F 1 -ATPase and K+ transport. • H+ co-transported with formate via FocA or coupled with F O F 1 proton translocation. • FocA contributes ion and pH homeostasis during fermentation in E. coli. [ABSTRACT FROM AUTHOR]

Background: The poor ovarian response (POR) to ovarian stimulation significantly decreases the efficiency of assisted reproduction technologies. The genesis of POR is not well understood, and can result from various genetic and immune factors. Purpose: To determine the role of genetic (number of CGG repeats in theFMR1-gene) and autoimmune factors (anti-ovarian antibodies) in POR in IVF programs. Methods: In a cross-sectional study, 150 infertile women were divided into the POR group (n = 65) and the group with a normal ovarian response (n = 85). All the patients underwent the detection of CGG repeats in theFMR1-gene by polymerase chain reaction, serum anti-zona pellucida antibodies (AZPA) and anti-ovarian antibodies by enzyme-linked immunosorbent assay. Results: The risk of POR was higher in patients with CGG counts > 34, but not in the patients with CGG counts < 26. The higher level of AZPA was found in the patients with the 26–34 CGG repeats compared to the patients with <26/> 34 CGG repeats. Conclusion: A higher number of CGG repeats in theFMR1-gene may be a risk factor of POR in IVF programs. Normal CGG counts in regard to ovarian reserve (26–34) suggest the autoimmune-driven POR. [ABSTRACT FROM PUBLISHER]

Abstract: The high altitude (∼3200m above sea level) of Aragats Space Environmental Center (ASEC) and low elevation of the thunderclouds provides a good opportunity to detect Thunderstorm Ground Enhancements (TGEs), particles of which rapidly attenuate in the atmosphere. In 2012, we have estimated the energy spectra of several TGEs and revealed significant electron fluxes extended till 30–40MeV. Measured in the one and the same event gamma ray and electron fluxes allow to estimate the height of the thundercloud above the detector. Proceeding from the energy spectra and the height of the cloud we estimate the electron spectra on the exit from the electric field of the thundercloud, the number of excess electrons in the cloud and avalanche multiplication rate. [Copyright &y& Elsevier]

Assesses the seismic and electromagnetic activity in the Kirgyz Tien Shan Range. Assessment of the electrical and seismic anomalies in the activated area; Evaluation of the released water during the tectonic activity of amphibole-bearing rocks; Characterization of the fluid phase on seismic and electric parameters of rock.

Malaria control and preventive activities in the countries of the World Health Organization Region for Europe (WHO/EUR) were strengthened within the framework of the Regional Roll Back Malaria strategy adopted by the member-states at the beginning of the 2000s. A political document "From control to malaria elimination" known as the "Tashkent Declaration" was unanimously endorsed by the member-states of the WHO/EUR with malaria problems in 2005. Since then, considerable progress has been achieved in the countries of the region, signified by the dramatic reduction of malaria incidence in conjunction with the prevention of re-establishment of infection on the territories where malaria was eliminated earlier. Several countries of the region had been certified by the WHO as free of local malaria transmission as a result of the activities of their National Malaria Elimination Programme, Armenia being one of the first in 2011. One of the main lessons learnt during the implementation of the activities by the National Malaria Elimination Programme in Armenia was that the development of an operational plan for malaria elimination required a comprehensive national effort. Full support, both political and financial, from the highest levels of government to smooth coordination between different government ministries, such as Agriculture, Defense, Finance, Health and Policy and Planning and others, was a prerequisite for operational success. The role and place of various partners in the achievement of malaria elimination in the country is discussed in this review. [ABSTRACT FROM AUTHOR]

Despite the substantial global impact of influenza, there are limited economic data to guide influenza vaccination programs investments in middle-income countries. We measured the costs of influenza and the costs of an influenza vaccination program in Armenia, using a societal perspective. During December 2022 through March 2023, retrospective cost data were collected from case-patients and healthcare providers through structured questionnaires at 15 healthcare facilities selected through stratified sampling. Medical costs included medications, laboratory costs, laboratory and diagnostic tests, and routine health care service costs and direct and indirect societal costs were included. Vaccination program costs from the 2021–2022 influenza season were identified using accounting records and categorized as: planning, distribution, training, social mobilization and outreach, supervision and monitoring, procurement, and national- and facility-level administration and storage. The mean costs per episode for SARI and ILI case-patients were $US 823.6 and $US 616.57, respectively. Healthcare service costs were the largest direct expenses for ILI and SARI case-patients. Total costs of the 2021–2022 influenza vaccination program to the government were $US 4,353,738, with the largest costs associated with national- and facility-level administration and storage (30% and 65% respectively). The total cost per dose administered was $US 25.61 ($US 7.73 per dose for procurement and $US 17.88 for the marginal administration cost per dose). These data on the costs of seasonal influenza prevention programs and the societal costs of influenza illness in Armenia may inform national vaccine policy decisions in Armenia and may be useful for other middle-income countries. Influenza vaccines, like other vaccine programs, are recognized as substantially contributing to the reduction disease burden and associated mortality and further driving economic growth. However, a formal cost-effectiveness analysis should be performed once burden of disease data are available. [ABSTRACT FROM AUTHOR]

Although healthcare personnel (HCP) are targeted for influenza vaccination they typically underutilize vaccines especially in low- and middle-income countries. We explored knowledge, attitudes, and practices of HCP about seasonal influenza vaccines (SIV) to identify factors associated with and modifiable barriers to SIV uptake. We pooled individual-level data from cross-sectional surveys about SIV conducted among health workers in 12 low- and middle- income countries during 2018–2020 (i.e., Albania, Armenia, Cote d'Ivoire, Kenya, Kyrgyzstan, Lao PDR, Lebanon, Morocco, North Macedonia, Tunisia, Tajikistan, and Uganda). Eleven countries used a standard protocol and questionnaire based on the Health Belief Model to measure perceptions of susceptibility and severity of influenza disease, benefits of, barriers to, and motivators for vaccination. We analyzed attitudes and perceptions among HCP, including acceptance of vaccine for themselves and willingness to recommend vaccines to patients, grouped by the presence/absence of a national influenza vaccination program. Models were adjusted for geographic region. Our analysis included 10,281 HCP from 12 countries representing four of the six World Health Organization regions: African, Eastern Mediterranean, European, and Western Pacific. The sample was distributed across low income (LIC) (3,183, 31 %), lower-middle (LMIC) (4,744, 46 %), and upper-middle income (UMIC) (2,354, 23 %) countries. Half (50 %) of the countries included in the analysis reported SIV use among HCP in both the year of and the year preceding data collection while the remainder had no influenza vaccination program for HCP. Seventy-four percent (6,341) of HCP reported that they would be willing to be vaccinated if the vaccine was provided free of charge. HCP in LICs were willing to pay prices for SIV representing a higher percentage of their country's annual health expenditure per capita (6.26 % [interquartile range, IQR: 3.13–12.52]) compared to HCP in LMICs and UMICs. HCP in countries with no SIV program were also willing to pay a higher percentage for SIV (5.01 % [IQR: 2.24–8.34]) compared to HCP in countries with SIV programs.. Most (85 %) HCP in our analysis would recommend vaccines to their patients, and those who would accept vaccines for themselves were 3 times more likely to recommend vaccines to their patients (OR 3.1 [95 % CI 1·8, 5·2]). Increasing uptake of SIV among HCP can amplify positive impacts of vaccination by increasing the likelihood that HCP recommend vaccines to their patients. Successful strategies to achieve increased uptake of vaccines include clear guidance from health authorities, interventions based on behavior change models, and access to vaccine free-of-charge. [ABSTRACT FROM AUTHOR]

Abstract: Strong electric fields inside thunderclouds give rise to enhanced fluxes of high-energy electrons and, consequently, gamma rays and neutrons. During thunderstorms at Mount Aragats, hundreds of Thunderstorm Ground Enhancements (TGEs) comprising millions of energetic electrons and gamma rays, as well as neutrons, were detected at Aragats Space Environmental Center (ASEC) on 3200m altitude. Observed large TGE events allow for the first time to measure the energy spectra of electrons and gamma rays well above the cosmic ray background. The energy spectra of the electrons have an exponential shape and extend up to 30–40MeV. Recovered energy spectra of the gamma rays are also exponential in energy range 5–10MeV, then turns to power law and extends up to 100MeV. [Copyright &y& Elsevier]

After introduction of rotavirus vaccine, other pathogens might become leading causes of hospitalizations for severe diarrhea among children <5 years of age. Our study in 33 hospitals in 7 countries found acute gastroenteritis accounted for most (84%) reported hospitalizations of children with diarrhea. Bloody and persistent diarrhea each accounted for <1%. [ABSTRACT FROM AUTHOR]

Background. The Republic of Armenia was 1 of the 2 earliest countries in the Newly Independent States to introduce rotavirus vaccine into its national immunization program to reduce the burden of rotavirus disease (documented to cause 38% of acute gastroenteritis hospitalizations [AGE] among children aged <5 years). In November 2012, RV1 (Rotarix) was introduced for Armenian infants at ages 6 and 12 weeks. Methods. The established active surveillance system at 2 hospitals in the capital, Yerevan, whereby children aged <5 years hospitalized for AGE have stool sample tested for rotavirus antigen, was used to assess trends in rotavirus hospitalizations. Immunization records on children enrolled after vaccine introduction were obtained from clinics, and vaccine effectiveness (VE) was estimated using children with AGE who test negative for rotavirus as controls for the rotavirus-positive cases. Results. Among infants, rotavirus hospitalizations were reduced by 48% within the first year after introduction, and by ≥75% in years 2 and 3 following introduction. Reductions of ≥30% in other young children too old to have been vaccinated suggest additional benefit through indirect protection; overall in year 3, rotavirus hospitalizations were reduced by 69% among children aged <5 years. The overall VE of 2 RV1 doses in protecting against rotavirus hospitalization (any severity) was 62% (95% confidence interval [CI], 36%–77%) among children aged 6–23 months; 68% (95% CI, 24%–86%) among those aged 6–11 months, and 60% (95% CI, 20%–80%) in children aged 12–23 months. Against more severe rotavirus disease, VE was 79% (95% CI, 55%–90%) and similarly high in both age groups. Conclusions. RV1 is effective in young Armenian children and substantially reduced rotavirus hospitalizations shortly after introduction. [ABSTRACT FROM AUTHOR]

Vavilovia formosa is a relict, endangered species from the highlands of the Caucasus and the Near East. Described in 1812, it has had an uncertain status and was finally recognized as a separate genus of tribe Fabeae ( Fabaceae). Our informal international group was established in 2007 to revive the interest in this species as it had been seriously neglected for decades. Here, we provide an overview of the accumulated knowledge on V. formosa and present the results of the most recent multidisciplinary research. Three expeditions were made to two locations in Armenia in 2009, providing the material for anatomical, morphological, chemical and molecular analysis. Unlike previous attempts, ex situ conservation in Yerevan and in vitro propagation, important for potential interspecific hybridization, were successful. Molecular tools were used to clarify the taxonomic position of V. formosa, often considered the closest to the extinct ancestor of the whole tribe. The analysis of four informative regions of plastid and nuclear DNA showed that V. formosa belongs to the same clade as Lathyrus and Pisum, with a distinct status. Preservation and maintenance of V. formosa remains the only basis for further development of all other scientific aspects, especially breeding and uses in agronomy. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 172, 524-531. [ABSTRACT FROM AUTHOR]

In mountainous and sub-mountainous zones of the Republic of Armenia farmers mainly grow beans, chickpeas, and peas. In addition there are very small crop areas (mainly homestead lands) of faba bean, soybean, mung bean, and grass pea. The village population does not know much about the cultivation of these plants. The data show that in 2007-2009 the specific weight of legume in overall cropland was approximately 94%, and about the 96% of the gross harvest. Local production needs appropriate marketing strategy. The research of local market showed that more attention should be paid to the consumption of goods produced by the farmer households, as well as to offer them to various consumer groups. [ABSTRACT FROM AUTHOR]

Vavilovia (Vavilovia formosa (Stev.) Fed.) belongs to the tribe Fabeae along with peas, vetchlings, vetches and lentils. It prefers high mountain areas in Armenia, Azerbaijan, Georgia, Iran, Iraq, Lebanon, Russia, Syria and Turkey. A true success in the ex situ conservation has recently been achieved, within the display plot Flora and Vegetation of Armenia in the Yerevan Botanic Garden. The hybridization between vavilovia and other Fabeae was done in the N. I. Vavilov Institute of Plant Industry with F1 seeds and F1 plants that did not produce the next generation. The recent molecular research showed that vavilovia belongs to a Lathyrus-Pisum-Vavilovia clade with a clearly distinct status. [ABSTRACT FROM AUTHOR]

The article presents a study which explores the anatomy of stem, leaf, and calyx of Vavilovia formosa. It notes that the anatomical examination results of the study showed that Vavilovia formosa has general anatomical structure that is characteristic for most of the plants of the family Fabaceae. The study suggests the anatomical features of the plant should be further analyzed for potential benefits that could be introduced to other cultivated Fabeae plants.

Background: Since the 90s’ E.multilocularis infection in foxes is rising and central-eastern European countries had seen first Alveolar echinococcosis (AE) human cases. AE is considered to be a very rare disease in Europe with average incidences of 0.03-0.20/100,000 inhabitants/year. Because of a suitable orography, this study aims to confirm whether there are human AE cases in Armenia, identify areas at risk, and also estimate AE annual incidence. Methods: Retrospective AE case finding was carried out at main 6 multiprofile medical centers equipped with the most innovative diagnostic means. The medical records of all patients with liver surgery admitted between January 2008 and June 2020 were reviewed. A specific form was developed in EpiInfo v. 7.2. Annual national incidence was estimated using population denominators provided by the National Institute of Statistics (the population of Armenia is estimated at 2 963 243 people). Results: From September 2019 until June 2020, overall 11 AE cases have been identified. All patients were diagnosed at advanced stages, with subsequent poor prognosis and costly treatment. Confirmation was based on tissue biopsy results. Age ranged from 19-59 years with a median of 39yrs. E. multilocularis was detected in rural communities, mostly in the Gegharkunik region (6 cases, 55%). Annual average incidence of AE was 0.033 varying between 0.032 in 2008 and 0.1 in 2017. For comparison with Armenia, an annual incidence in France was 0.026/100,000 in 2008 (the population of France is estimated at 65 273 511 people). Conclusions: All cases were not notified by the surveillance system and the real prevalence of AE in the country is unknown. This young age could indicate widespread of infection in animals. Therefore, the burden of AE disease is difficult to estimate. The surveillance system in Armenia can be improved by the development of national guidelines for the prospective registry, AE awareness campaigns. Key messages: First-time identification of human AE in Armenia calls for implementation of surveillance with a case definition and registry of all cases. AE is an emerging, and so far silent threat in Armenia. [ABSTRACT FROM AUTHOR]

The article presents a study which aims to assess the chemical composition of the vegetative and generative organs of Vavilovia formosa. It provides a percentage content of the microlements and macroelements in Vavilovia formosa on a dry matter basis. It notes that the study offers a solid background for further testing of its tolerance, as well as assessing its nutritional value.

The article presents a study which examines the morphology of the reproductive organs of Vavilovia formosa. The study gives emphasis on the androecium and gynoecium and describes some basic cytogenetics of the species. The study provides a detailed taxonomical description of the species which can help determine its mating system that may prove helpful for its in situ and ex situ conservation.