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Formaldehyde is not only a ubiquitous chemical pollutant in indoor environments but also a reactive carbonyl species in biological processes. Formaldehyde is endogenously produced through the essential biological processes, including mitochondrial one-carbon metabolism, metabolite oxidation, and nuclear epigenetic modifications. High electrophilic property allows it high reactivity with a wide variety of biological nucleophiles, which can be beneficial or detrimental to cellular function depending on the situation. Therefore, it is important to develop non-invasive sensing technique for monitoring the roles and functions of FA in biological processes. So, development of a rapid, sensitive and facile method to determine the concentration of FA becomes highly desirable. Fluorescence detection technique is highly attractive because of its high selectivity, sensitivity and real-time approach. This review article focuses on various design strategies of the fluorescent probes, their sensing mechanism for detecting formaldehyde in environment as well as in living cells based on different recognition groups from 2017 onward. This area still in prime focus because of the rapid development of the fluorescence probes from lab to indoor in near future. [ABSTRACT FROM AUTHOR]

Fluorescent organic-inorganic mesoporous hybrid materials have been prepared and characterised, and their behaviour against nitroaromatic explosives have been tested. MCM-41 silica was used as an inorganic scaffold and pyrene ( P derivative containing trialkoxysilane moieties), dansyl and fluorescein ( D and F derivatives also containing trialkoxysilane groups, respectively) fluorophores have been anchored on hybrid materials by a co-condensation method to obtain a homogenous distribution of dyes into the pores of the support. Six sensing materials have been prepared, of which SP, SD, SF were hydrophilic and SPh, SDh, SFh were hydrophobic. Template-free hydrophilic materials ( SP, SD, SF) were obtained after repeated NH4NO3/ethanol extractions under temperature from as-synthesised ( MP, MD and MF supports, respectively) solids. Hydrophobic materials (SPh, SDh, SFh) were prepared by using excess 1,1,1,3,3,3-hexamethyldisilazane with template-free hydrophilic ( SP, SD and SF) materials. The six final materials displayed the typical emission bands of the grafted fluorophores. In particular, SP and SPh show the typical pyrene monomer (370-420 nm) and excimer (430-600 nm) emissions. SD and SDh exhibit the broad dansyl fluorescence band in the 450-600 nm range, whereas solids SF and SFh present sharp fluorescein emission centred at 525 nm. The fluorescent behaviour of the six final materials was tested in the presence of explosives (pentaerythritol tetranitrate (PETN), hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), nitrobenzene (NB), 1,3,5-trinitrobenzene (TNB), 2,4,6-trinitrotoluene (TNT), 2,4-dinitrotoluene (DNT), 2,4,6-trinitrophenylmethylnitramine (Tetryl) and picric acid (PA)). Only nitroaromatic compounds were able to induce emission quenching. As a general trend, the quenching degree depended on the nature of the final material. The best response was obtained with explosives PA and Tetryl, which were able to significantly quench the emission of the sensing supports. The observed quenching was ascribed to the π-π stacking interactions between the electron-donor fluorophores and the electron-withdrawing nitroaromatic explosives. When using SPh for Tetryl and PA, the limits of detection were 8.5 and 1.4 ppm, respectively, whereas they were 14.4 and 1.2 ppm for SDh. Principal component analysis algorithms were applied to the fluorescence measurements taken with the six hybrid materials and the seven explosives. The obtained score plot showed well-defined clusters for the seven explosives tested. Finally, solid SDh was applied to detect trace amounts of Tetryl in soil samples with good results. [ABSTRACT FROM AUTHOR]

Forests provide a source of livelihood to all classes of rural people, especially in tribal dominated areas. With the advent of joint forest management concepts and commercial earning prospects from non-timber forest products (NTFPs), it was expected that forests would be best preserved by the villagers who depend on them for a substantial part of their livelihoods. However, in the case of the Ranibundh block in the Bankura district, it was observed that the predominance of private agencies in marketing channels of NTFPs, together with risk of eviction, loss of customary right to access forest resources, low employment prospects, and lack of training about proper management of NTFPs have led to the failure in motivating the forest dwellers to prevent degradation of forest resources. It is suggested that government agencies, producer institutions, non-governmental organizations (NGOs), and other strong institutional entities can promote forest preservation when complemented by the granting of forest rights to rural people, the extension of training facilities, and alternative employment prospects. [ABSTRACT FROM AUTHOR]

Degradation of common pool resource (CPR) in developing countries has often been traced to high rate attached by poor people in discounting future flow of benefits, market failure, pressure on carrying capacity or sometimes property right failure. However, the concept of poorly enforced property right and particularly risk of eviction as a measure of insecurity of land tenure has not been adequately examined in the context of degradation of CPR. A game theoretic framework is developed where degradation of forest grazing land is explained in terms of changes in perceived risk of eviction from the encroached land. Logit regression is applied to empirically analyse the impact of perceived fear of reduced access and other variables on the state of degradation. For this purpose, a sample of seven villages is considered in tribal dominated region in West Bengal, India. It is observed that apart from a number of socio-economic variables like poverty, mutual trust and other incomes, perceived fear of eviction (represented as a dummy variable) arising from insecurity of forest land tenure, has a significant impact on forest degradation status in the study region. [ABSTRACT FROM AUTHOR]

A new Pd(ii) bounded 2D-hexagonally ordered functionalized MCM-41 type material (IV) has been synthesized. Functionalization was carried out by the anchoring of 3-aminopropyltriethoxysilane in the MCM-41 type mesoporous material, followed by grafting with 2,6-diacetylpyridine (DAP) to give a N3-type Schiff base chelating attachment for the Pd(ii) species. Fourier transform infrared (FTIR), powder X-ray diffraction (PXRD) and high resolution transmission electron microscopy (HRTEM) studies have been used to characterize the material. Material IVbehaves as a highly active catalyst towards Suzuki–Miyaura cross-coupling reaction for the synthesis of biaryl organics. In addition, IVacts as a true heterogeneous catalyst in coupling reaction. It was found that this catalyst is highly efficient and recyclable towards Suzuki–Miyaura reaction with high turn over frequencies. X-Ray photoelectron spectroscopic (XPS) analysis was employed to understand the oxidation state of the palladium atom in the catalyst (IV) and its loading in the material. [ABSTRACT FROM AUTHOR]