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Old dog,new trick:The PHR-sPX system regulates arbuscular mycorrhizal symbiosis

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Molecular Plant 2022年第2期15卷 225-227页

作者： Debatosh das Caroline Gutjahr CUHk shenzhen Research Institute No.10 Yuexing 2nd RoadNanshanShenzhenChina Plant Genetics TUM School of Life SciencesTechnical University of Munich(TUM)Emil Ramann Strasse 485354 FreisingGermany

Plant growth depends on the continuous availability of the macro-nutrient phosphate(Pi).However,in most soils,Pi is only poorly accessible to plants,resulting in Pi deficiency and triggering a number of Pi starvation *** strategy of plants to over-come Pi limitation is to form a symbiosis with arbuscular mycor-rhizal(AM)fungi(smith et al.,2011),which occurs with approximately 80%of land *** fungi improve the uptake of Pi and other mineral nutrients and thereby increase plant performance and stress *** collect these minerals with an extraradical hyphal network from the soil and release them from highly branched structures,called arbuscules,into root cortex ***,Pi sufficiency causes inhibition of internal root colonization(Balzergue et al.,2011;Breuillin et al.,2010).The mechanistic basis for this has long remained *** studies have now solved this long-standing mystery and demonstrated that a canonical Pi-response regulatory module regulates AM symbiosis in accordance with the plant Pi status(shi et al.,2021;das et al.,2022).

关键词： thereby symbiosis release

Conserving the zoological resources of Bangladesh under a changing climate

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Integrative Zoology 2009年第2期4卷 213-219页

作者： Bidhan C.das Department of Zoology University of RajshahiRajshahiBangladesh

It is now well recognized that Bangladesh is one of the world’s most vulnerable countries to climate change and sea level *** levels of natural resources and a high occurrence of natural disasters further add to the challenges faced by the *** impacts of climate change are anticipated to exacerbate these existing stresses and constitute a serious impediment to poverty reduction and economic *** and biodiversity are important key sectors of the economy and natural resources of the country are selected as the most vulnerable to climate *** is for these reasons that Bangladesh should prepare to conserve its natural resources under changed climatic ***,the development of specific strategies and policies to address the effects of climate change on the ecosystem and on biodiversity has not commenced in ***,I present a detailed review of animal resources of Bangladesh,an outline of the major areas in zoological research to be integrated to adapt to climate change,and identified few components for each of the aforesaid areas in relation to the natural resource conservation and management in the country.

关键词： Bangladesh climate change conservation integrative approach.

Visible Light Excitable sCN^- selective Fluorescence Probe Derived from Thiophene

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Chinese Journal of Chemistry 2015年第10期33卷 1173-1177页

作者： sudipta das sisir Lohar Jesus sanmartin Matalobos Debasis das Department of Chemistry The University of Burdwan Burdwan 713104 West Bengal India Departamento de Qu'tmicalnorg'anica Facultade de Qutmica Avda. Das Ciencias s/n 15782 Santiago de Compostela Spain

An efficient fluorescence probe, 4-methyl-2,6-bis（（thiophen-2-ylmethylimino）methyl）phenol （DFPTMA） and its sCN adduct has been synthesized and characterized by different spectroscopic techniques like ^1H NMR,^13C NMR, QTOF-Ms Es^＋, UV-Vis and FTIR spectroscopy. single crystal X-ray structure of DFPTMA is reported. In presence of sCN-, DFPTMA exhibits significant fluorescence enhancement （λEx, 455 nm, λEm, 504 nm） in aqueous methanol （water-methanol, 1 ： 4, V/V, 0.1 mol/L HEPEs buffer, pH 7.4）. Common bio-relevant anions viz. CH3COO^-, NO2, NO7, Cl^-, Br^-, I^-, sO4^2-, HsO4^-, N3^-, HAsO4^2-, Cr2O7^2-, H2PO4, ClO4^-, NCO^-, CN^-, CO3^2-, F^-, PO4^3-, s2-, Hs- do not interfere in the recognition of sCN-. Lowest detection limit for sCN^- is 0.88 μmol/L with response time 〈5 min. The sCN assisted enhancement in emission intensity may be attributed to the formation of H-bond which enhances the rigidity of the molecular assembly.

关键词： visible light excitation sCN^- fluorescence thiophene derivative

Community ecology and spatial distribution of trees in a tropical wet evergreen forest in kaptai national park in Chittagong Hill Tracts, Bangladesh

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Journal of Forestry Research 2014年第2期25卷 311-318页

作者： s. M. Feroz Md Rabiul Alam Prokash das Abdullah Al Mamun Forestry and Wood Technology Discipline Khulna Universtity

We investigated the floristic composition, woody species diversity and spatial distribution of trees in a tropical wet evergreen forest in kaptai national park in Chittagong Hill Tracks, Bangladesh. We recorded 25 families, 37 genera, 40 species and 1771 woody individuals in a 0.09 ha plot. Euphorbiaceae and Moraceae were the most species- rich families, and Castanopsis, Ficus and Terminaliawere the most species-rich genera. Bursera serrata Wall. ex Colebr. was the dominant species in terms of highest importance value （13%）. Trema orientalis （L.） B1 was typically a light demanding species as it appeared in the top can- opy with only one individual having the seventh highest IV, but had no regeneration. The expected maximum number of species （smax） was 140, indicating that many species may invade the forest as the sm~ is greater than the recorded total number of species. The nature of the disappear- ance and appearance of species in the present forest reflects instability of floristic composition. The values of shannon＇s index H＇ and Pielou＇s index J＇（evenness） were 3.36 bit and 0.63, respectively. These values show moderately high species diversity as compared to other subtropical forests in the tropics. In addition, a sample area of 200 m2 in this forest would be sufficient for measuring the diversity indices H＂ and ,/＇, whereas the trend of J＇may indicate the rate of equality of individuals among the different species decreased with increasing area. The distribu- tion pattern for the total stand was completely random. However, the dominant species showed aggregate distribution for small areas, but random distribution for large areas. The spatial association between species showed that the strongest positive interspecific association occurred between streblus asper Lour. and Castanea indica Roxh. （09 = 0.51）. As a whole, most species were weakly associated with each other, of which 58% species associations were completely negative. The result of cluster analysis s

关键词： Chittagong Hill Tracts floristic composition spatial distribution of trees tropical wet evergreen forest woody species diversity

Fabrication of plasmonic nanopyramidal array as flexible sERs substrate for biosensing application

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Nano Research 2023年第1期16卷 1132-1140页

作者： Anindita das Udit Pant Cuong Cao Rakesh sMoirangthem Hitesh Bhanudas.k.mble Nanophotonics Lab Department of PhysicsIndian Institute of Technology(Indian School of Mines)Dhanbad-826004India Institute for Global Food security School of Biological SciencesQueen’s University of Belfast19 Chlorine GardensBelfastBT95DLUK Material and Advanced Technologies for Healthcare Queen’s University of Belfast18-30 Malone RoadBelfastBT95BNUK IITB Nanofabrication Facility Department of Electrical EngineeringIndian Institute of TechnologyBombay-400076India

The proposed work aims to develop a sensitive surface-enhanced Raman spectroscopy(sERs)*** inverted nano pyramid array on silicon substrate fabricated using electron beam lithography(EBL)was utilised as a master template and the mold was later replicated via nanoimprinting process to prepare gold-coated polymer nanopyramid three-dimensional(3D)sERs *** fast and versatile replication process using nanoimprinting lithography(NIL)can produce polymer nanopyramids in a low-cost and reproducible ***,the proposed fabrication protocol can be easily upscale for large scale *** intense electric field confinement at nanotips and four edges of gold-coated polymer nanopyramid enhanced the Raman signal of probe molecules,i.e.,Rhodamine 6G with a limit of detection down to 3.277×10−9 M was *** work also underlines the efficiency of gold-coated polymer nanopyramid arrays in the spectral detection of hemoglobin proteins at low *** Raman signal enhancement mechanism was further studied through the electromagnetic simulation using COMsOL *** addition,bending test experiments were performed to understand the effect of flexibility on sERs signal *** fabricated gold-coated polymer nanopyramids arrays could pave the way for the development of low-cost sERs platforms for the detection of hazardous biological and chemical compounds at ultra-low concentrations in practical applications.

关键词： nanopyramids surface-enhanced Raman spectroscopy(sERs) flexible hemoglobin protein nanoimprinting replica molding

Alteration of chemical behavior of L-ascorbic acid in combination with nickel sulfate at different pH solutions in vitro

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Asian Pacific Journal of Tropical Biomedicine 2012年第3期2卷 220-222页

作者： shaheen A Maniyar Jameel G Jargar swastika N das salim A Dhundasi kusal k das Environmental Health Research Unit Department of PhysiologyAl Aineen Medical College Department of Engineering Chemistry B.L.D.E.A's V.P.Dr.P.G.Halakatti College of Engineering and Technology

Objective:To evaluate the alteration of chemical behavior of L-ascorbic acid(vitamin C) with metal ion(nickel) at different pH solutions in ***:spectra of pure aqueous solution of L-ascorbic acid(E mark) compound and NisO_4(H_2O)(sigma UsA) were evaluated by UV visible *** analysis of L-ascorbic acid and nickel at various pH(2.0, 7.0,7.4 and 8.6) at room temperature of 29℃ was *** this special analysis,combined solution of L-ascorbic acid and nickel sulfate at different pH was also ***:The result revealed that λ_(max)(peak wavelength of spectra) of L-ascorbic acid at pH 2.0 was 289.0 run whereas at neutral pH 7.0,λ_(max) was 29s.4 *** alkaline pH 8.6,λ_(max) was 295.4 nm and at pH 7.4 the λ_(max) of L-ascorbic acid remained the same as 295.4 *** solution at acidic pH 2.0 was 394.5 nm,whereas at neutral pH 7.0 and pH 7.4 were the same as 394.5 *** at alkaline pH 8.6,λ_(max) value of nickel sulfate became 392.0 *** combined solution of L-ascorbic acid and nickel sulfate(6 mg/mL each) at pH 2.0 showed 292.5 nm and 392.5 nm,respectively whereas at pH 7.0,L-ascorbic acid showed 296.5 nm and nickel sulfate showed 391.5 *** pH 7.4,L-ascorbic acid showed 297.0 nm and nickel sulfate showed 394.0 nm in the combined solution whereas at pH 8.6(alkaline) L-ascorbic acid and nickel sulfate were showing 297.0 and 393.5 nm,respectively. Conclusions:Results clearly indicate an altered chemical behavior of L-ascorbic acid either alone or in combination with nickel sulfate in vitro at different *** oxidation of L-ascorbic acid to L-dehydro ascorbic acid via the free radical(Hsc*) generation from the reaction of H,Asc + Ni(Ⅱ) is the cause of such alteration of λ_(max),value of L-ascorbic acid in the presence of metal nickel.

关键词： L-ascorbic acid Nickel pH spectrum Chemical behavior spectra UV visible spectrophotometer Peak wavelength Free radical Vitamin C Nickel sulfate

Magnetic and ferroelectric properties of Zn and Mn co-doped BaTiO_3

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Chinese Physics B 2015年第6期24卷 564-570页

作者： sangram keshari das Binod kumar Roul Institute of Materials science

This paper reports an approach to obtaining multiferroic properties in co-doped （Zn：Mn） BaTiO3 near room temper- ature. Interestingly, an unusual magnetic hysteresis loop is observed in the co-doped compositions in which the central portion of the loop is squeezed. However, in the composition ***3, a broad magnetic hysteresis loop is observed. such a magnetic effect is attributed to the coexistence of antiferromagnetic and ferromagnetic exchange in- teractions in the system. The observation of the above type of magnetic properties is likely to be due to the presence of exchange interactions between Mn ions. A lossy-type of ferroelectric hysteresis loop is also observed in co-doped ceramic compositions near room temperature.

关键词： ferroelectrics ceramic ferromagnetic

Distribution of mineral species in different coal seams of Talcher coalfield and its transformation behavior at varying temperatures

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International Journal of Coal science & Technology 2016年第2期3卷 97-103页

作者： Amit Banerjee P. R. Mishra Ashok Mohanty k. Chakravarty R. das Biswas R. sahu s. Chakravarty Analytical Chemistry Division CSIR - NationalMetallurgical Laboratory Jamshedpur Jharkhand 831007India Department of Metallurgical and Materials Engineering National Institute of Technology JamshedpurJharkhand 831014 India R&D Tata Steel Ltd Jamshedpur Jharkhand 831007 India

Mineral phase characterization and thorough understanding of its transformation behavior during combustion are imperative to know the potential utilization of coal in the thermal industries. The primary objective of this work is to analyze the quality of Indian Coals and obtain their mineral species-specific information at different depths. The samples were obtained from Talcher Coalfield, Odisha, India. Coal from four seam sections in the Talcher coalfield, India are mainly high ash coal （〉50 %） and volatile matter deceases along with the seam depth. XRD results show that the major mineral phases present in the coal are quartz and kaolinite. siderite, illite, and anatase were found in minor quantities. It has been observed that the clay minerals （kaolinite, silimanite, illite） decompose at higher temperature and traces of dolomite, mullite, hematite etc. are formed during the process of combustion. Among the four seams （M2, M12, M24 and M43） studied, ash of M43 has high A1203%, TIO2% and k20% content and low sIO2%, CaO% and MgO% content. High acid- to-base ratios contributed to high ash fusion temperatures （IDT 〉 1500 ℃） and low slagging potential of the coals studied. Relatively low fouling index （〈0.3） was estimated for all the coal seams studied. Furthermore, thermodynamic modeling software, Factsage, have been used to envision the mineral phase transformations that take place between 800 and 1500℃ during coal combustion.

关键词： Proximate analysis - Ultimate analysis Factsage XRD AFT Talcher coalfield

Rheological behavior of semi-solid TiB_2 reinforced Al composite

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Transactions of Nonferrous Metals society of China 2015年第9期25卷 2827-2832页

作者： s.THADELA B.MANDAL P.das H.ROY A.k.LOHAR s.k.sAMANTA Near Net shape Manufacturing Technology Group CSIR-Central Mechanical Engineering Research Institute NDT & Metallurgy Group CSIR-Central Mechanical Engineering Research Institute

The rheological behavior of the semi-solid Ti B2 reinforced Al-Mg alloy composite slurry was investigated,which is required for the mould filling simulations during the semi-solid *** B2 reinforced in-situ Al-Mg alloy composite samples were remelted and subsequently brought to the semi-solid temperature regime within the heating chamber of a searle type *** order to understand the rheological behavior of composites,three different types of experiment were carried out,namely,steady state test,continuous cooling test and isothermal *** from that,the thixotropic nature of the slurry was confirmed from the obtained hysteresis loops during the *** results indicate that when isothermally held,the composite slurry exhibits pseudo-plasticity and shows shear-thinning behavior up to the shear rate of 1300 s^-1,and at higher shear rates（1300 s^-1）,it shows a shear thickening tendency,which is probably due to the agglomeration of non-deformable nano-Ti B2 *** pseudo-plastic behavior of the slurry was also estimated employing intermittent step changes of shear rate（shear jump test）.

关键词： rheology shear thinning in-situ nano-Ti B2 thixotropy shear thickening