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This study explores the bulk crystal growth, structural characterization, and physical property measurements of the cubic double perovskite Ba2CoWO6 (BCWO). In BCWO, Co²âº ions form a face-centered cubic (FCC) lattice with non-distorted cobalt octahedra. The compound exhibits long-range antiferromagnetic order below T_N = 14 K. A slight anisotropy in the magnetization data is observed, along with a spin-flop transition at 10 kOe , a saturation field of 310 kOe at 1.6 K, and an ordered moment of 2.17 µB. Heat capacity measurements indicate an effective j = 1/2 ground state configuration, resulting from the combined effects of the crystal electric field and spin-orbit interaction. Optical property analysis reveals two gaps in the UV-Visible region, suggesting potential applications in photocatalysis and photovoltaics. The magnetic and optical properties highlight the significant role of orbital contributions within BCWO, indicating various other potential applications.
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The chilling process will surely be a very cost-effective measure for repeated mass rearing and be an effective source for the requirements of a huge number of pupae collected and supplied for the sterile insect technique (SIT) program. In Bangladesh, blowfly (Lucilia cuprina) is a main cause of damage of marine fish during sun drying in coastal areas. The chilling for a certain duration at a certain temperature may store pupae for a specific time by reducing their metabolism. In this study, the effect of chilling temperature and exposure period on pupal developmental arrest was assessed and the subsequent impact on quality control parameters of the adult blowfly, L. cuprina was also observed. We considered the effects of three temperature (4, 7, and 10 °C) regimes and three exposure periods (10, 20, and 30 days) on 3-day-old pupae. Results showed that all the parameters were affected significantly by all the chilling temperatures and durations. Adult emergence, flight ability, pupal weight, adult longevity, fecundity, and fertility decreased with the increase of exposure duration, but partial emergence and pupal duration increased with exposure durations. Storages at 4 °C for 20 and 30 days had no adult emergence. Emergence occurred before the chilling duration at 10 °C for 20 and 30 days which clearly indicated the unsuitable condition for storage parameters. Though the emergence, flight ability, pupal weight, and longevity at 10 °C for 10 days had no significant difference with control, the fecundity and fertility did have a significant difference. In addition, treatment at 7 °C for 10days, the adult emergence, flight ability, pupal weight, longevity, fecundity, fertility, pre-oviposition, and oviposition period had no significant difference with control. Considering all the parameters, it can be concluded that the pupae of L. cuprina can be stored at 7 °C of chilling temperature for 10 days long without any deterioration towards the quality of adult flies.
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Quantum spin liquids (QSLs) are novel phases of matter which remain quantum disordered even at the lowest temperature. They are characterized by emergent gauge fields and fractionalized quasiparticles. Here we show that the sub-kelvin thermal transport of the three-dimensional S=1/2 hyperhyperkagome quantum magnet PbCuTe_{2}O_{6} is governed by a sizeable charge-neutral fermionic contribution which is compatible with the itinerant fractionalized excitations of a spinon Fermi surface. We demonstrate that this hallmark feature of the QSL state is remarkably robust against sample crystallinity, large magnetic field, and field-induced magnetic order, ruling out the imitation of QSL features by extrinsic effects. Our findings thus reveal the characteristic low-energy features of PbCuTe_{2}O_{6} which qualify this compound as a true QSL material.
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Mobile money has become a lifeline for millions of poor people who have limited access to a formal banking system. It encompasses a wide range of benefits such as women's empowerment, risk sharing, improved labor market outcomes and reductions in poverty. In this paper, we ask whether mobile money can help lift people out of poverty. Previous studies have addressed this question by using microanalyses of field experiments or longitudinal data on rural households, whereas we use district-level data to reevaluate the mobile money-poverty nexus. In particular, we study the impact of mobile money on district-level poverty in Bangladesh over the period 2010-2016. Our study finds that every 1 billion Taka (approximately US$ 11.76 million) increase in mobile money transactions via the bKash system in 2015 is associated with 0.71% point reduction in the poverty rate in Bangladesh. The marginal impact ranges from 0.12 to 1.15% points across the districts categorized in five groups as per 2010 poverty rates. The findings suggest that mobile money has been successful in fostering various poverty reduction initiatives and that targeted policy prescriptions can be devised to lift up poorer societies that are still outside the purview of mobile financial services. To further increase mobile money use, the government could use its own infrastructure to enhance mobile agent density in the poorest sectors of society.
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ETHNOPHARMACOLOGICAL RELEVANCE: Indigenous knowledge of medicinal plants is an integral part of the primary health care (PHC) system in almost every society. For more than two centuries, Munda, a small ethnic group in Bangladesh, has lived around the Sundarbans, the world's largest mangrove forest. This mangrove is rich in biodiversity but is threatened by global climate change. Information on the therapeutic use of plants by Munda ethnic minorities remains completely unknown. Therefore, it needs urgent documentation. AIM OF THE STUDY: The purpose of the study is (1) to search and compile data on the diversity of medicinal plants used by the Munda people for PHC needs, and (2) Quantitative analysis of these data to identify important medicinal plants and diseases related to treatment by this species. MATERIAL AND METHODS: We conducted repeated field surveys and interviews among 79 Munda informants to collect ethnobotanical data. Informants were selected through random sampling techniques and interviewed using an open and semi-structured questionnaire. We reported the primary (absolute) data as use reports (URs) with frequency citation (FC). The International Classification of Primary Care-2 (ICPC-2) was followed to categorize the therapeutic use of medicinal plants, and quantitative analysis was performed using the FC and informant consensus factor (ICF). RESULTS: The present study explored and compiled a total of 3199 medicinal URs for 98 medicinal plant species to treat 132 ailment conditions under sixteen (16) ICPC-2 pathological groups. The highest URs (948) were noted for the digestive (D) group treated by 69 plant species, where the highest ICF value was measured for the social problem (Z) disease category (ICF: 1.00). Of the recorded medicinal plants, 17 were identified as true Mangrove (MNG), 24 as Mangrove Associates (MNA), and 57 as Non-Mangrove (NMG) species. Fabaceae (13 species) represented the leading family, followed by Lamiaceae and Compositae (5 species). Herbs (43%) have shown dominant life forms, and the leaves (41%) were frequently used plant parts. The most commonly cited preparation method was juice (24%), and the prevalent mode of administration was oral (62%). Azadirachta indica A. Juss. was the most widely used therapeutic plant species based on FC (39) values. The comparative literature review study reveals that the practices of 15 plants and their ethnomedicinal use by the Munda people are still entirely unexplored and newly reported in Bangladesh. Additionally, therapeutic use of 2 species, Brownlowia tersa (L.) Kosterm., and Dalbergia candenatensis (Dennst.) Prain has not been previously reported worldwide. In addition, 51 plant species (52%) of the total plants studied enlisted on the IUCN Red List of Threatened Species. CONCLUSION: To our knowledge, this is the first ethnobotanical study on the Munda ethnic group in Bangladesh. This study indicates that Munda people still rely on medicinal plants for PHC and have a rich and varied traditional knowledge about the therapeutic use of plants. This study also warns of the high risk of the current availability status of plants in the study area. Therefore, this study calls for urgent steps to protect and conserve high-risk plants that can be done by taking both in-situ and ex-situ measures. In addition, further phytochemical and pharmacological investigations of the important medicinal plants cited in the study have been suggested.
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Minorias Étnicas e Raciais , Etnobotânica , Medicina Tradicional/métodos , Fitoterapia , Plantas Medicinais , Áreas Alagadas , Adulto , Idoso , Bangladesh , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Several plants have traditionally been used since antiquity to treat various gastroenteritis and respiratory symptoms similar to COVID-19 outcomes. The common symptoms of COVID-19 include fever or chills, cold, cough, flu, headache, diarrhoea, tiredness/fatigue, sore throat, loss of taste or smell, asthma, shortness of breath, or difficulty breathing, etc. This study aims to find out the plants and plant-derived products which are being used by the COVID-19 infected patients in Bangladesh and how those plants are being used for the management of COVID-19 symptoms. In this study, online and partially in-person survey interviews were carried out among Bangladeshi respondents. We selected Bangladeshi COVID-19 patients who were detected Coronavirus positive (+) by RT-PCR nucleic acid test and later recovered. Furthermore, identified plant species from the surveys were thoroughly investigated for safety and efficacy based on the previous ethnomedicinal usage reports. Based on the published data, they were also reviewed for their significant potentialities as antiviral, anti-inflammatory, and immunomodulatory agents. We explored comprehensive information about a total of 26 plant species, belonging to 23 genera and 17 different botanical families, used in COVID-19 treatment as home remedies by the respondents. Most of the plants and plant-derived products were collected directly from the local marketplace. According to our survey results, greatly top 5 cited plant species measured as per the highest RFC value are Camellia sinensis (1.0) > Allium sativum (0.984) > Azadirachta indica (0.966) > Zingiber officinale (0.966) > Syzygium aromaticum (0.943). Previously published ethnomedicinal usage reports, antiviral, anti-inflammatory, and immunomodulatory activity of the concerned plant species also support our results. Thus, the survey and review analysis simultaneously reveals that these reported plants and plant-derived products might be promising candidates for the treatment of COVID-19. Moreover, this study clarifies the reported plants for their safety during COVID-19 management and thereby supporting them to include in any future pre-clinical and clinical investigation for developing herbal COVID-19 therapeutics.
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Lambertianic acid (LA) is a diterpene bioactive compound mainly purified from different species of Pinus. It is an optical isomer of another natural compound daniellic acid and was firstly purified from Pinus lambertiana. LA can be synthesized in laboratory from podocarpic acid. It has been reported to have potential health benefits in attenuating obesity, allergies and different cancers including breast, liver, lung and prostate cancer. It exhibits anticancer properties through inhibiting cancer cell proliferation and survival, and inducing apoptosis, targeting major signalling components including AKT, AMPK, NFkB, COX-2, STAT3, etc. Most of the studies with LA were done using in vitro models, thus warranting future investigations with animal models to evaluate its pharmacological effects such as antidiabetic, anti-inflammatory and neuroprotective effects as well as to explore the underlying molecular mechanisms and toxicological profile. This review describes the chemistry, source, purification and therapeutic potentials of LA and it can therefore be a suitable guideline for any future study with LA.
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Ácidos Carboxílicos/química , Ácidos Carboxílicos/uso terapêutico , Naftalenos/química , Naftalenos/uso terapêutico , Ácidos Carboxílicos/isolamento & purificação , Humanos , Hiperlipidemias/tratamento farmacológico , Hipersensibilidade/tratamento farmacológico , Naftalenos/isolamento & purificação , Neoplasias/tratamento farmacológico , Obesidade/tratamento farmacológicoRESUMO
An extensive study has been made to identify, document, and investigate the ethnomedicinal plants used by Rakhine ethnic minorities in Patuakhali and Barguna District of southern Bangladesh for the term of April 2018 to June 2019. In this article, we have focused on the Rakhine population trends, management concerns, and some actions for conserving the Rakhine population diversity in the study area. In this study, we have identified the locations where Rakhine population lives in Patuakhali and Barguna districts. A total of 86 plant species belonging to 71 genera and 43 families were reported to be used for treating more than 57 various physical ailments under 14 illness categories from the study area. For each of the species, the botanic name, common name, Rakhine name, family, habit, parts used and traditional medicinal uses of the plant species have been presented. The maximum numbers of ethnomedicinal plant species were utilized to treat gastrointestinal complaints (43) taken after by the treatment of dermatological issues (36). The highly cited (75.60%) plant species were found to be Ananas comosus and Aegle marmelos used for gastro-intestinal (Stomach pain, indigestion, and dysentery) digestive disorders and subsequently followed by Colocasia esculenta (70.73%) used for cut, bleeding and wound healing. The results of this study have shown that Rakhine indigenous communities still depend on conventional plant-based medication to remedy various diseases and therapeutic purposes in the study area. Our findings have also shown that despite there have adequate phytodiversity in the natural habitat of the study area but the number of Rakhine population has been declining significantly day-by-day. As an ultimate result, we have lost the plant-based traditional medicinal knowledge of Rakhine indigenous communities in Bangladesh. As a rich source of traditional knowledge and cultural diversity, it calls for urgent initiatives to conserve the cultural heritage of the Rakhine community as well as the diversity of Rakhine ethnic group.
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Etnicidade , Etnobotânica , Medicina Tradicional , Aceitação pelo Paciente de Cuidados de Saúde , Fitoterapia , Extratos Vegetais/uso terapêutico , Plantas Medicinais , Aegle , Ananas , Bangladesh , Colocasia , Doenças do Sistema Digestório/tratamento farmacológico , Documentação , Etnofarmacologia , Humanos , Conhecimento , Dermatopatias/tratamento farmacológico , Inquéritos e Questionários , CicatrizaçãoRESUMO
The quantum spin liquid is a highly entangled magnetic state characterized by the absence of static magnetism in its ground state. Instead, the spins fluctuate in a highly correlated way down to the lowest temperatures. Quantum spin liquids are very rare and are confined to a few specific cases where the interactions between the magnetic ions cannot be simultaneously satisfied (known as frustration). Lattices with magnetic ions in triangular or tetrahedral arrangements, which interact via isotropic antiferromagnetic interactions, can generate such a frustration. Three-dimensional isotropic spin liquids have mostly been sought in materials where the magnetic ions form pyrochlore or hyperkagome lattices. Here we present a three-dimensional lattice called the hyper-hyperkagome that enables spin liquid behaviour and manifests in the compound PbCuTe2O6. Using a combination of experiment and theory, we show that this system exhibits signs of being a quantum spin liquid with no detectable static magnetism together with the presence of diffuse continua in the magnetic spectrum suggestive of fractional spinon excitations.
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The pyrochlore material Nd_{2}Zr_{2}O_{7} with an "all-in-all-out" (AIAO) magnetic order shows novel quantum moment fragmentation with gapped flat dynamical spin ice modes. The parametrized spin Hamiltonian with a dominant frustrated ferromagnetic transverse term reveals a proximity to a U(1) spin liquid. Here we study the magnetic excitations of Nd_{2}Zr_{2}O_{7} above the ordering temperature (T_{N}) using high-energy-resolution inelastic neutron scattering. We find strong spin ice correlations at zero energy with the disappearance of gapped magnon excitations of the AIAO order. It seems that the gap to the dynamical spin ice closes above T_{N} and the system enters a quantum spin ice state competing with and suppressing the AIAO order. Classical Monte Carlo simulations, molecular dynamics, and quantum boson calculations support the existence of a Coulombic phase above T_{N}. Our findings relate the magnetic ordering of Nd_{2}Zr_{2}O_{7} with the Higgs mechanism and provide explanations for several previously reported experimental features.
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Almost a century ago, string states-complex bound states of magnetic excitations-were predicted to exist in one-dimensional quantum magnets. However, despite many theoretical studies, the experimental realization and identification of string states in a condensed-matter system have yet to be achieved. Here we use high-resolution terahertz spectroscopy to resolve string states in the antiferromagnetic Heisenberg-Ising chain SrCo2V2O8 in strong longitudinal magnetic fields. In the field-induced quantum-critical regime, we identify strings and fractional magnetic excitations that are accurately described by the Bethe ansatz. Close to quantum criticality, the string excitations govern the quantum spin dynamics, whereas the fractional excitations, which are dominant at low energies, reflect the antiferromagnetic quantum fluctuations. Today, Bethe's result is important not only in the field of quantum magnetism but also more broadly, including in the study of cold atoms and in string theory; hence, we anticipate that our work will shed light on the study of complex many-body systems in general.
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A detailed diffraction study of Ca10Cr7O28 is presented which adds significant new insights into the structural and magnetic properties of this compound. A new crystal structure type was used where the a and b axes are doubled compared to previous models providing a more plausible structure where all crystallographic sites are fully occupied. The presence of two different valences of chromium was verified and the locations of the magnetic Cr5+ and non-magnetic Cr6+ ions were identified. The Cr5+ ions have spin-[Formula: see text] and form distorted kagome bilayers which are stacked in an ABC arrangement along the c axis. These results lay the foundation for understanding of the quantum spin liquid behavior in Ca10Cr7O28 which has recently been reported in Balz et al (2016 Nat. Phys. 12 942).
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This corrects the article DOI: 10.1103/PhysRevLett.116.147201.
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We report on ultrasound and magnetization studies in three-dimensional, spin-dimerized Sr_{3}Cr_{2}O_{8} as a function of temperature and external magnetic field up to 61 T. It is well established [A. A. Aczel et al., Phys. Rev. Lett. 103, 207203 (2009)] that this system exhibits a magnonic-superfluid phase between 30 and 60 T and below 8 K. By mapping ultrasound and magnetization anomalies as a function of magnetic field and temperature we establish that this superfluid phase is embedded in a domelike phase regime of a high-temperature magnonic liquid extending up to 18 K. Compared to thermodynamic results, our study indicates that the magnonic liquid could be characterized by an Ising-like order but has lost the coherence of the transverse components.
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There is currently limited knowledge on the role of hormones in plants responses to combinations of abiotic and pathogen stress factors. This study focused on the response of tomato near-isogenic lines (NILs) that carry the Ol-1, ol-2, and Ol-4 loci, conferring resistance to tomato powdery mildew (PM) caused by Oidium neolycopersici, to combined PM and salt stress. These NILs were crossed with the notabilis (ABA-deficient), defenceless1 (JA-deficient), and epinastic (ET overproducer) tomato mutants to investigate possible roles of hormone signaling in response to combined stresses. In the NILs, marker genes for hormonal pathways showed differential expression patterns upon PM infection. The epinastic mutation resulted in breakdown of resistance in NIL-Ol-1 and NIL-ol-2. This was accompanied by reduced callose deposition, and was more pronounced under combined salt stress. The notabilis mutation resulted in H2O2 overproduction and reduced susceptibility to PM in NIL-Ol-1 under combined stress, but lead to higher plant growth reduction under salinity and combined stress. Resistance in NIL-ol-2 was compromised by the notabilis mutation, which was potentially caused by reduction of callose deposition. Under combined stress the compromised resistance in NIL-ol-2 was restored. PM resistance in NIL-Ol-4 remained robust across all mutant and treatment combinations. Hormone signaling is critical to the response to combined stress and PM, in terms of resistance and plant fitness. ABA appears to be at the crossroads of disease susceptibility/senescence and plant performance under combined stress These gained insights can aid in narrowing down targets for improving crop performance under stress combinations.
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The spin dynamics and magnetic excitations of the slightly distorted triangular s = 3/2 system α-CaCr (2)O (4) are investigated by means of Raman spectroscopy and electron spin resonance (ESR) to elucidate its peculiar magnetic properties. Two-magnon excitations in circular RL symmetry show a multi-maximum structure with a dominant spectral weight at low energies. The temperature dependence of the ESR linewidth is described by a critical broadening ΔH(pp)(T) is proportional to (T-T(N ))(-p) with the exponent p = 0.38(5) - 0.48(3) for temperatures above T(N) = 42.6 K. The exponent is much smaller than that of other s = 3/2 triangular lattices. This is ascribed to soft roton-like modes, indicative of the instability of a helical 120° phase. As an origin we discuss a complex spin topology formed by four inequivalent nearest neighbor and sizable next-nearest neighbor interactions.
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In this Letter, we explore the phase diagram and excitations of a distorted triangular lattice antiferromagnet. The unique two-dimensional distortion considered here is very different from the "isosceles"-type distortion that has been extensively investigated. We show that it is able to stabilize a 120° spin structure for a large range of exchange interaction values, while new structures are found for extreme distortions. A physical realization of this model is α-CaCr(2)O(4), which has a 120° structure but lies very close to the phase boundary. This is verified by inelastic neutron scattering which reveals unusual rotonlike minima at reciprocal space points different from those corresponding to the magnetic order.
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It is widely believed that magnetic excitations become increasingly incoherent as the temperature is raised due to random collisions which limit their lifetime. This picture is based on spin-wave calculations for gapless magnets in 2 and 3 dimensions and is observed experimentally as a symmetric Lorentzian broadening in energy. Here, we investigate a three-dimensional dimer antiferromagnet and find unexpectedly that the broadening is asymmetric-indicating that far from thermal decoherence, the excitations behave collectively like a strongly correlated gas. This result suggests that a temperature activated coherent state of quasiparticles is not confined to special cases like the highly dimerized spin-1/2 chain but is found generally in dimerized antiferromagnets of all dimensionalities and perhaps gapped magnets in general.
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In this study an immuno-array for Abeta42 based on scanning tunneling microscopy (STM) was developed using conjugated gold nanoparticle (Au-NP) and antibody (Ab) complex. Fragmented monoclonal Ab against Abeta42 was allowed to immobilize on the Au-dot arrays followed by its target protein Abeta42 and Au NP and Ab complex. The surface structure of Au-NP and Ab complex on Au-dots was investigated with Atomic Force Microscopy and the current profile of fabricated immunosensing element was investigated with STM. The power spectrum derived from the current profile was found to be increasing with higher concentrations of Abeta42 having a detection limit of 100 fg/ml. The proposed technique can be a promising method to construct the highly sensitive and efficient protein chip of immunosensors arrays.
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Peptídeos beta-Amiloides/análise , Eletroquímica/métodos , Microscopia de Tunelamento/métodos , Fragmentos de Peptídeos/análise , Análise Serial de Proteínas , Ouro/química , Limite de Detecção , Nanopartículas MetálicasRESUMO
Diapause pupae of the swallowtail butterfly Papilio xuthus L. exhibit diapause-green, orange and brownish-orange color polymorphism. Development of orange pupae involves a neuroendocrine factor inducing orange pupa (Orange-Pupa-Inducing Factor, OPIF), which is secreted from the head-thoracic region during late pharate pupal stages, in particular from the ganglia of short-day animals located posteriorly from the second thoracic ganglion2 (TG2). This report describes certain properties of OPIF using bioassays involving ligated abdomens of short-day pharate pupae. Localization of OPIF in the central nervous system of short-day larvae indicated that it was present predominantly in TG2, thoracic ganglion3 (TG3) and abdominal ganglion1 (AG1) complexes. OPIF activity in TG(2,3)-AG1 complexes was over two times higher than in the more posteriorely located ganglia. The developmental profile of OPIF in last instar short-day larvae revealed that OPIF activity in larval ganglia posterior to TG2 became gradually higher as larval growth proceeded, suggesting that OPIF might be accumulated in TG(2,3)-AG(1-7) complexes as larvae prepare for pupal molting. Furthermore, ligated abdomens of short-day larvae developed into pupae of an orange type when a 2% NaCl extract containing OPIF prepared from TG(2,3)-AG(1-7) complexes of long-day larvae was injected into ligated abdomens of short-day pharate pupae, indicating that OPIF is also present in long-day larvae. Additionally, a biochemical investigation using gel filtration chromatography showed that the molecular weight of OPIF was about 10 kDa.