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Toxoplasma gondii infections are common in humans and animals worldwide. Domestic free-range chickens (Gallus domesticus) are excellent sentinels of environmental contamination with T. gondii oocysts because they feed on the ground. Chickens can be easily infected with T. gondii; however, clinical toxoplasmosis is rare in these hosts. Chickens are comparatively inexpensive and thus are good sentinel animals for T. gondii infections on the farms. Here, the authors reviewed prevalence, the persistence of infection, clinical disease, epidemiology and genetic diversity of T. gondii strains isolated from chickens worldwide for the past decade. Data on phenotypic and molecular characteristics of 794 viable T. gondii strains from chickens are discussed, including new data on T. gondii isolates from chickens in Brazil. This paper will be of interest to biologists, epidemiologists, veterinarians and parasitologists.
Despite a reduction in maternal mortality in recent years, a high rate of anaemia and other nutrient inadequacies during pregnancy pose a serious threat to mothers and their children in the Global South. Using the framework of the WHO–Commission on Social Determinants of Health, this study examines the socioeconomic, programmatic and contextual factors associated with the consumption of iron and folic acid (IFA) tablets/syrup for at least 100 d (IFA100) and receiving supplementary food (SF) by pregnant women in India.
We analysed a nationally representative cross-sectional survey of over 190 898 ever-married women aged 15–49 years who were interviewed as part of the National Family Health Survey (NFHS) conducted during 2015–16, who had at least one live birth preceding 5 years of the survey.
All twenty-nine states and seven union territories of India.
Ever-married women aged 15–49 years.
Less than one-third of women were found to be consuming IFA100, and a little over half received SF during their last pregnancy. The consumption of IFA100 was likely to improve with women’s education, household wealth, early and more prenatal visits, and in a community with high pregnancy registration. Higher parity, early and more prenatal visits, contact with community health workers during pregnancy, belonging to a poor household and living in an aggregated poor community and rural area positively determine whether a woman might receive SF during pregnancy.
Continuous monitoring and evaluation of provisioning IFA and SF in targeted groups and communities is a key to expanding the coverage and reducing the burden of undernutrition during pregnancy.
To assess the role of white-tailed deer (Odocoileus virginianus, WTD) in the epidemiology of toxoplasmosis, we conducted a national survey of WTD across the USA for Toxoplasma gondii infection. To do this, we combined serology with parasite isolation to evaluate the prevalence and genetic diversity of T. gondii in this game species. From October 2012 to March 2019, serum and tissues were collected from 914 WTD across the USA. Serum samples were screened for antibodies to T. gondii, and then the tissues of seropositive WTD were bioassayed in mice. Antibodies were detected in 329 (36%) of 914 WTD tested by the modified agglutination test (positive reaction at 1:25 or higher). Viable T. gondii was isolated from the heart of 36 WTD from 11 states. Three of the 36 isolates were pathogenic but not highly virulent to outbred Swiss Webster mice and all 36 isolates could be propagated further in cell culture and were genotyped. For genotyping, DNA extracted from cell culture-derived tachyzoites was characterized by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) using the genetic markers SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 and Apico. Genotyping revealed seven ToxoDB PCR-RFLP genotypes, including 24 isolates for genotype #5 (haplogroup 12), four isolates for #2 (type III, haplogroup 3), three isolates for genotypes #1 (type II, haplogroup 2), two isolates for genotypes #3 (type II, haplogroup 2) and one isolate each for #39, #221 and #224. Genotype #5 was the most frequently isolated, accounting for 66.6% (24 of 36) of the isolates. Combining the 36 isolates from this study with previously reported 69 isolates from WTD, 15 genotypes have been identified. Among these, 50.4% (53/105) isolates belong to genotype #5. Our results indicate moderate genetic diversity of T. gondii in WTD. The results also indicate that undercooked venison should not be consumed by humans or fed to cats.
Methane (CH4) consumption in agricultural soil is imperative for the mitigation of climate change. However, the effect of tillage and cropping systems on CH4 consumption is less studied. Experiments were carried out in Madhya Pradesh, India with soybean-wheat (SW), maize-wheat (MW) and maize-gram (MG) cropping systems under conventional tillage (CT) and no-tillage (NT). Soybean/maize was cultivated during the kharif season (July–October) and wheat/chickpea in the rabi season (October–March) for 9 years consecutively. Soil samples were collected during vegetative growth stages of soybean and maize from different cropping systems. Methane consumption, the abundance of methanotrophs as particulate methane monooxygenase (pmoA) gene copies, soil and crop parameters were estimated. Methane consumption rate was higher in NT and upper soil layer (0–5 cm) than CT and 5–15 cm depth. Methane consumption rate k ranged from 0.35 to 0.56 μg CH4 consumed/g soil/d in the order of MW>SW>MG in 0–5 cm. The abundance of pmoA gene copies ranged from 43 × 104/g soil to 13 × 104/g soil and was highest in MW-NT and lowest in MG-CT. Available nitrogen, phosphorus and potassium were higher in 0–5 cm than in 5–15 cm depth. Soil and plant parameters and abundance of pmoA genes correlated significantly and positively with CH4 consumption rate. No-tillage stimulated CH4 consumption compared to CT irrespective of cropping system and CH4 consumption potential was highest in MW and lowest in MG. However, the magnitude of the positive effect of NT towards CH4 consumption was higher in SW and MG than MW.
Biodegradation of chlorpyrifos under the influence of fertilizer application and climate factors such as elevated CO2, temperature and moisture was studied. Soybean was grown in control, inorganic, organic and integrated (both inorganic and organic) fertilized fields. Rhizospheric soils collected during the vegetative growth phase were amended with chlorpyrifos (10 μg/g soil) and incubated under different climate factors. The climate factors were CO2 concentration (400, 800 ppm), temperature (25, 45°C) and moisture-holding capacity (60, 100%). Chlorpyrifos degradation rate varied from 0.28 to 0.65 μg/g soil/d. The abundance of 16S rRNA gene copies of eubacteria varied from 13 × 106 to 7 × 105/g soil. Actinomycetes-specific 16S rRNA gene copies were in the range of 62.5 × 105 to 18.5 × 103/g soil. Microbial abundance was high in organic amended soil and low in control soil irrespective of climate factors. Elevated CO2 and high temperature inhibited (P < 0.05) chlorpyrifos degradation rate and the abundance of 16S rRNA genes of eubacteria and actinomycetes. Chlorpyrifos degradation followed as: organic > integrated > inorganic > control. The degradation rate was positively correlated (P < 0.01) with the soil organic C, available N, water-stable aggregates and mean weight diameter of the soil aggregates of soil. Principal component analysis denoted temperature and fertilizer as the major components of variation. The study highlights that elevated CO2 and temperature affect chlorpyrifos biodegradation; however, the effect can be alleviated by the amendment of organic fertilizer.
The year 1937 saw the establishment of Congress Ministries in eight of the eleven provinces in which the provincial elections had been held, Bihar being one of them. The resounding victory of the Congress which secured a clear majority in the province of Bihar and the dismal performance of the Muslim League seemed at the time to depict the mood of the people in general. It was taken as a clear rejection of the politics of communalism and separatism and as an expression of faith in the secular credentials of the Indian National Congress. However, less than a decade later, the province was gripped by severe communal tensions and had become one of the most prominent parts of India from where the movement for Pakistan drew support. This article thus explores the nature of the communal violence that occurred in Bihar in 1946 against the backdrop of the ‘escalating’ communal tensions during the late 1930s and early 1940s. It seeks to problematise the dichotomy that exists in literature on communal violence between moments of what have been called ‘extraordinary’ violence (such as riots) and the everyday structures of (what Gyanendra Pandey has called) ‘routine violence’. Through its analysis of contemporary material produced by the Muslim League, the Congress Ministry and the provincial British administration to explain the causes of the 1946 riots in Bihar, it argues that it is in the moments of rupture presented by riots that everyday structures of violence are trivialised or normalised through processes of ‘dichotomisation’, ‘dehumanisation’ and ‘denial’.
Feral swine are known reservoirs of various pathogens, including Toxoplasma gondii. Here, we report the first national survey of viable T. gondii in feral swine in the USA. We paired serological surveys with parasite isolation and bioassay to evaluate the prevalence and genetic diversity of these parasites. From 2012–2017, sera and tissues from 1517 feral swine across the USA were collected for the isolation of viable T. gondii. Serum samples were initially screened for antibodies to T. gondii, and then the tissues of seropositive feral swine were bioassayed in mice. Antibodies were detected in 27.7% of feral swine tested by the modified agglutination test (1:25 or higher). Antibody positive rates increased significantly with age, with 10.1% of juveniles, 16.0% of sub-adults and 38.4% of adults testing seropositive. Myocardium (50 g) from 232 seropositive feral swine was digested in pepsin and bioassayed in mice. Viable T. gondii was isolated from 78 feral swine from 21 states. Twelve of the 78 isolates were pathogenic to outbred Swiss Webster mice and 76 of the 78 isolates could be propagated further in cell culture and were genotyped. For genotyping, deoxyribonucleic acid extracted from cell culture-derived tachyzoites was characterized by polymerase chain reaction restriction fragment length polymorphism using the genetic markers SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 and Apico. Genotyping revealed 15 ToxoDB genotypes, including 43 isolates for genotype #5 (haplogroup 12), 11 isolates for #24, four isolates for #2 (haplogroup 3), two isolates for each of genotypes #3 (haplogroup 2), #4 (haplogroup 12), #216, #221, #289 and #297 and one isolate for each of genotypes #1 (haplogroup 2), #39, #66, #260, #261 and #299. Genotype #5 was the most frequently isolated, accounted for 57% (43/76) of the isolates, followed by #24, accounted for 14% (11/76). Genotypes #260, #289, #297 and #299 are new types. Genotype #289 was highly virulent to mice and originated from feral swine collected in Louisiana on the same day at the same location. Genotype #216 was previously demonstrated to be highly virulent to mice. Our results indicate moderate genetic diversity of T. gondii in feral swine in the USA, with the genotype #5 (haplogroup 12) dominant in the continental USA, whereas genotype #24 (10/14) was dominant in Hawaii, suggesting different population structures of the parasites among the two distinct geographical locations.
This text grew out of the group theory lectures taught by the first author to undergraduate students at IIT Bombay. While most students attending the course were majoring in physics, there were also students from electrical, mechanical and aerospace engineering streams. The continued interest of students in the topic motivated us to compile the contents into a textbook suitable for a course pitched at the undergraduate level. We also hope that the text will be useful to researchers who wish to familiarize themselves with the basic principles and typical examples of applications of group theory in physics.
In our day-to-day life as well as in the laboratories, we observe patterns with symmetry. These could be in the symmetric shape of the wings of a butterfly, the arrangement of atoms in a molecule, the shape of nuclei as inferred by advanced experimental techniques, among many others. Group theory is a mathematical formulation of such symmetries. While group theory is of interest in mathematics, the prevalence of symmetries in the physical world enable it to find applications in several other disciplines. For instance, the synthesis of molecules in chemistry, crystallographic structures in physics, elasticity properties in continuum mechanics, etc., require the basics of the symmetry principles.
Understanding complex physical systems in nature by solving complicated mathematical equations can be a daunting task. Group theory offers an elegant and powerful framework to extract certain details about such complex systems. For example, the underlying group symmetry can assert whether a given scattering or decay process is allowed or forbidden without performing any explicit computation. This book employs solved examples as well as a variety of exercises (sometimes drawn from sources listed in the Bibliography) to help the reader appreciate the role of group theory in explaining certain experimental observations. We have tried to balance between the formal mathematical aspects and the applications so that the student can effortlessly absorb the group theory arguments behind ad hoc postulates and selection rules. The contents and presentation style enable undergraduate students to connect with the physics they have learned, or will be learning in courses like quantum mechanics, continuum mechanics, atomic and molecular physics, condensed matter physics, nuclear physics, and particle physics in their undergraduate curriculum.