Impact of Ammonium on Syntrophic Organohalide-Respiring and Fermenting Microbial Communities

Citation: Delgado, A. G., Fajardo-Williams, D., Kegerreis, K. L., Parameswaran, P., & Krajmalnik-Brown, R. (2016). Impact of Ammonium on Syntrophic Organohalide-Respiring and Fermenting Microbial Communities. Msphere, 1(2), 10. doi:10.1128/mSphere.00053-16Syntrophic interactions between organohalide-respiring and fermentative microorganisms are critical for effective bioremediation of halogenated compounds. This work investigated the effect of ammonium concentration (up to 4 g liter(-1) NH4+-N) on trichloroethene-reducing Dehalococcoides mccartyi and Geobacteraceae in microbial communities fed lactate and methanol. We found that production of ethene by D. mccartyi occurred in mineral medium containing = 1 g liter(-1) NH4+-N, organohalide-respiring dynamics shifted from D. mccartyi and Geobacteraceae to mainly D. mccartyi. An increasing concentration of ammonium was coupled to lower metabolic rates, longer lag times, and lower gene abundances for all microbial processes studied. The methanol fermentation pathway to acetate and H-2 was conserved, regardless of the ammonium concentration provided. However, lactate fermentation shifted from propionic to acetogenic at concentrations of >= 2 g liter(-1) NH4+-N. Our study findings strongly support a tolerance of D. mccartyi to high ammonium concentrations, highlighting the feasibility of organohalide respiration in ammonium-contaminated subsurface environments. IMPORTANCE Contamination with ammonium and chlorinated solvents has been reported in numerous subsurface environments, and these chemicals bring significant challenges for in situ bioremediation. Dehalococcoides mccartyi is able to reduce the chlorinated solvent trichloroethene to the nontoxic end product ethene. Fermentative bacteria are of central importance for organohalide respiration and bioremediation to provide D. mccartyi with H2, their electron donor, acetate, their carbon source, and other micronutrients. In this study, we found that high concentrations of ammonium negatively correlated with rates of trichloroethene reductive dehalogenation and fermentation. However, detoxification of trichloroethene to nontoxic ethene occurred even at ammonium concentrations typical of those found in animal waste (up to >= 2 g liter(-1) NH4+-N). To date, hundreds of subsurface environments have been bioremediated through the unique metabolic capability of D. mccartyi. These findings extend our knowledge of D. mccartyi and provide insight for bioremediation of sites contaminated with chlorinated solvents and ammonium

A Rejoinder on Energy versus Impact Indicators

Citation distributions are so skewed that using the mean or any other central tendency measure is ill-advised. Unlike G. Prathap's scalar measures (Energy, Exergy, and Entropy or EEE), the Integrated Impact Indicator (I3) is based on non-parametric statistics using the (100) percentiles of the distribution. Observed values can be tested against expected ones; impact can be qualified at the article level and then aggregated.Comment: Scientometrics, in pres

Impaired Glucose Tolerance in Acute ST Elevation Myocardial Infarction - A Perspective study.

INTRODUCTION : Acute Myocardial Infarction is a serious and life threatening disorder. There are various risk factors for the development of Acute Myocardial Infarction. Of them, the most important and the one which is causing havoc among South Asian and Indian population is the relationship between abnormal glucose metabolism and Acute Myocardial Infarction. It is a well known fact that Diabetes Mellitus, a full blown form of abnormal glucose metabolism is associated with increased risk of cardiovascular events like AMI, unstable angina, Cerebrovascular events like stroke & also with peripheral vascular disease. Whether the new concept of Impaired Glucose Tolerance, Impaired Fasting Glucose also have similar effects on the morbidity and mortality of the patients with AMI & their relationship is either causal or casual needs to be urgently evaluated. Also, the incidence of Impaired Glucose Tolerance, Impaired Fasting Glucose is increasing in the population especially among the Indians and South East Asians. The Impaired Glucose Tolerance, Impaired Fasting Glucose are considered as prediabetic state, in the contemporary literature. Whether the detection of an individual in this prediabetic state & proper treatment with life style modification can bring down the risk of future cardio vascular events like Unstable Angina, AMI are questions to be answered. AIMS OF THE STUDY ; 1. To compare and contrast the in-hospital outcomes of patients with Acute Myocardial infarction with normal Glucose Metabolism and Abnormal Glucose Metabolism – Impaired Glucose Tolerance. 2. To study the effect of Impaired Glucose Tolerance on the left ventricular function in these patients. 3. To assess the functional capacity of the patients with Myocardial infarction with Impaired Glucose Tolerance. CONCLUSION : Impaired Glucose Tolerance in patients with Acute ST elevation Myocardial Infarction is associated with ; increased incidence of arrhythmias, increased incidence of Congestive Heart Failure, increased incidence of recurrent angina, increased incidence of Left Ventricular Clot, increased incidence of in-hospital death. Impaired Glucose Tolerance is also associated with decrease in the left ventricular function as suggested by decrease in the ejection fraction in this group of patients and increase in the Wall Motion Score Index. Impaired Glucose Tolerance is associated with decrease in the functional capacity during the Pre discharge Treadmill Test

Influence of active stiffening on dynamic behaviour of piezo-hygro-thermo-elastic composite plates and shells

The active stiffening and active compensation analyses are carried out to present the influence of active stiffness on the dynamic behaviour of piezo-hygro-thermo-elastic laminates. A coupled piezoelectric finite element formulation involving a hygrothermal strain field is derived using the virtual work principle and is employed in a nine-noded field consistent Lagrangian element. The closed-loop system is modelled with elastic stiffness, active stiffness introduced by isotropic actuator lamina and geometric stiffness due to stresses developed by hygrothermal strain. Through a parametric study, the influence of active stiffening and active compensation effects on the dynamics of cross-ply and angle-ply laminated plates and shells are highlighted. The active stiffening on thin shells is significantly influenced by boundary effects and the actuator efficiency further decreases with increase in curvature. The reduction in natural frequencies of cross-ply laminates due to hygrothermal strain is actively compensated by active stiffening; however, it is observed that the actuator performance reduces significantly with increase in curvature particularly in angle-ply laminates, which demands the use of directional actuators. The active stiffening and active compensation effects are low in moderately thick piezo-hygro-thermo-elastic plates and shells, which are less influenced by boundary conditions

Proof over promise: towards a more inclusive ranking of Dutch academics in Economics & Business

The Dutch Economics top-40, based on publications in ISI listed journals, is - to the best of our knowledge - the oldest ranking of individual academics in Economics and is well accepted in the Dutch academic community. However, this ranking is based on publication volume, rather than on the actual impact of the publications in question. This paper therefore uses two relatively new metrics, the citations per author per year (CAY) metric and the individual annual h-index (hIa) to provide two alternative, citation-based, rankings of Dutch academics in Economics & Business. As a data source, we use Google Scholar instead of ISI to provide a more comprehensive measure of impact, including citations to and from publications in non-ISI listed journals, books, working and conference papers. The resulting rankings are shown to be substantially different from the original ranking based on publications. Just like other research metrics, the CAY or hIa-index should never be used as the sole criterion to evaluate academics. However, we do argue that the hIa-index and the related citations per author per year metric provide an important additional perspective over and above a ranking based on publications in high impact journals alone. Citation-based rankings are also shown to inject a higher level of diversity in terms of age, gender, discipline and academic affiliation and thus appear to be more inclusive of a wider range of scholarship

EXPERIMENTAL ANALYSIS ON THE STRENGTH OF FOAMED CONCRETE BLOCKS

Foamed concrete, also known as cellular concrete or aerated concrete, is an innovative construction material that is gaining significant attention in the building industry due to its lightweight nature, excellent thermal and acoustic insulation properties, and cost-effectiveness. Foamed concrete is produced by introducing air bubbles into a cement-based mixture, resulting in a porous structure that reduces its overall density without compromising its strength and durability. This experimental analysis investigates the strength characteristics of foamed concrete blocks, focusing on key factors such as compressive strength, flexural strength, and the influence of various mix proportions on the material\u27s performance. The study aims to determine the optimal mix design for achieving a balance between lightweight properties and sufficient strength, making foamed concrete blocks suitable for a wide range of applications, including non-load-bearing walls, partitions, and insulation panels.The first phase of the study involves the preparation of foamed concrete mixes using different proportions of cement, sand, water, and foam.The density of the foamed concrete blocks is varied by adjusting the water-to-cement ratio, the type and amount of foaming agent, and the curing conditions. The physical properties, such as density, water absorption, and shrinkage, are evaluated to determine how these factors influence the strength and durability of the foamed concrete blocks.The experimental results for foamed concrete blocks with a mix proportion of (1:2.5:0.40:0.05) have provided valuable insights into their structural and economic viability. The compressive strength of the foamed concrete is measured at 6.4 MPa, while the flexural strength is 2.5 MPa. When compared to conventional concrete, these values are relatively lower, as traditional concrete exhibits significantly higher compressive and flexural strength properties and foamed concrete blocks are econimical as compared to conventional concrete blocks However, despite this reduced strength, foamed concrete has several notable advantages that make it a practical and efficient alternative for various construction applications

Phylogeography of mtDNA haplogroup R7 in the Indian peninsula.

BACKGROUND: Human genetic diversity observed in Indian subcontinent is second only to that of Africa. This implies an early settlement and demographic growth soon after the first 'Out-of-Africa' dispersal of anatomically modern humans in Late Pleistocene. In contrast to this perspective, linguistic diversity in India has been thought to derive from more recent population movements and episodes of contact. With the exception of Dravidian, which origin and relatedness to other language phyla is obscure, all the language families in India can be linked to language families spoken in different regions of Eurasia. Mitochondrial DNA and Y chromosome evidence has supported largely local evolution of the genetic lineages of the majority of Dravidian and Indo-European speaking populations, but there is no consensus yet on the question of whether the Munda (Austro-Asiatic) speaking populations originated in India or derive from a relatively recent migration from further East. RESULTS: Here, we report the analysis of 35 novel complete mtDNA sequences from India which refine the structure of Indian-specific varieties of haplogroup R. Detailed analysis of haplogroup R7, coupled with a survey of approximately 12,000 mtDNAs from caste and tribal groups over the entire Indian subcontinent, reveals that one of its more recently derived branches (R7a1), is particularly frequent among Munda-speaking tribal groups. This branch is nested within diverse R7 lineages found among Dravidian and Indo-European speakers of India. We have inferred from this that a subset of Munda-speaking groups have acquired R7 relatively recently. Furthermore, we find that the distribution of R7a1 within the Munda-speakers is largely restricted to one of the sub-branches (Kherwari) of northern Munda languages. This evidence does not support the hypothesis that the Austro-Asiatic speakers are the primary source of the R7 variation. Statistical analyses suggest a significant correlation between genetic variation and geography, rather than between genes and languages. CONCLUSION: Our high-resolution phylogeographic study, involving diverse linguistic groups in India, suggests that the high frequency of mtDNA haplogroup R7 among Munda speaking populations of India can be explained best by gene flow from linguistically different populations of Indian subcontinent. The conclusion is based on the observation that among Indo-Europeans, and particularly in Dravidians, the haplogroup is, despite its lower frequency, phylogenetically more divergent, while among the Munda speakers only one sub-clade of R7, i.e. R7a1, can be observed. It is noteworthy that though R7 is autochthonous to India, and arises from the root of hg R, its distribution and phylogeography in India is not uniform. This suggests the more ancient establishment of an autochthonous matrilineal genetic structure, and that isolation in the Pleistocene, lineage loss through drift, and endogamy of prehistoric and historic groups have greatly inhibited genetic homogenization and geographical uniformity.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

Two-Party Threshold Key Agreement Protocol for MANETs using Pairings

In MANET environment, the nodes are mobile i.e., nodes move in and out dynamically. This causes difficulty in maintaining a central trusted authority say Certification Authority CA or Key Generation Centre KCG. In addition most of cryptographic techniques need a key to be shared between the two communicating entities. So to introduce security in MANET environment, there is a basic need of sharing a key between the two communicating entities without the use of central trusted authority. So we present a decentralized two-party key agreement protocol using pairings and threshold cryptography ideas. Our model is based on Joux2019;s three-party key agreement protocol which does not authenticate the users and hence is vulnerable to man-in-the-middle attack. This model protects from man-in-the-middle attack using threshold cryptography

FORMULATION AND IN VITRO EVALUATION OF GASTRORETENTIVE FAMOTIDINE HOLLOW MICROSPHERES

The main aim of this study is to develop a gastro retentive multiple unit floating drug delivery system for a drug which is poorly absorbed from lower gastrointestinal tract of famotidine. The hollow micro spheres were prepared by the emulsion solvent diffusion technique using eudragit RS 100 as a release rate controlling polymer in the ratios 1:1, 1:2 ,1:3,and 1:4.The prepared microspheres were evaluated for drug-polymer compatibility, micromeritic properties, drug entrapment efficiency, in-vitro buoyancy and drug release studies. The mean particle size increased with increase in the polymer concentration. The micromeritic properties were found to be improved when compared to pure drug .Scanning electron microscopy confirmed the hollow structure with smooth external surface. The drug and polymer were found to be compatible as seen in IR studies. The entrapment efficiency of formulation E1-E4 were 70.42%, 70.12%, 69.22% and 67.78% and for the formulation C1-C4 were 72.19%, 68.67%, 67.14% and 66.87%, cellulose acetate containing microspheres showed a desirable high drug content and entrapment efficiency respectively. The microspheres floated up to 10 h over the surface of the gastric buffer medium and the buoyancy percentage was found to be in the range of 60-39% of E1-E4and C1-C4. In-vitro drug release studies showed that the prepared microspheres exhibited prolonged drug release for more than 12 hours. The mechanism of drug release wasfound to be a combination of both peppas and zero order release kinetics. The developed floating microspheres of aceclofenac may be used for prolonged drug release for at least 12 h for maximizing the therapeutic efficacy along with patient compliance. Keywords: Famotidine, Ethyl acetate, acetone, Eudragit RL100, Higuchi's model, PVA, scanning electron microscopy