An insight into the influence of low dose irradiation pretreatment on the microbial decolouration and degradation of Reactive Red-120 dye

The influence of low dose irradiation pretreatment on the microbial decolouration and degradation of Reactive Red-120 (RR-120) dye was investigated in detail by using Pseudomonas sp. SUK1. About 27%, 56% and 66% decolouration of 150 ppm RR-120 dye solution was observed by applying 0, 0.5 and 1 kGy doses, respectively, in the first step followed by microbial treatment for 24 h under static condition. Similarly, about 70%, 88% and 90% TOC removal was observed by applying 0, 0.5 and 1 kGy doses, respectively, in the first step followed by the microbial treatment for 96 h under static condition. The radiation induced fragmented products of RR-120 at doses of 0.5 and 1 kGy were investigated by FTIR and electrospray ionization-MS analysis. The induction of the enzymes viz. laccase, tyrosinase, azoreductase and NADH-2,6-dichlorophenol indophenol reductase was studied in the decolourised solution obtained after irradiating 150 ppm RR-120 dye solution with 0 and 1 kGy doses followed by the microbial treatment for 96 h under static condition. The enzymatic degradation products were studied by FTIR, HPLC and GC–MS. The toxicity study of the treated dye solution on plants revealed the degradation of RR-120 into non-toxic products by combined radiation-microbial treatment. This study explores a reliable and promising way to use industrially viable dose (?1 kGy) and microbial strain viz. Pseudomonas sp. SUK1 for permissible safe disposal of dye solutions from textile industries.     

Phytoremediation potential of Petunia grandiflora Juss., an ornamental plant to degrade a disperse, disulfonated triphenylmethane textile dye Brilliant Blue G

Phytoremediation provides an ecofriendly alternative for the treatment of pollutants like textile dyes. The purpose of this study was to explore phytoremediation potential of Petunia grandiflora Juss. by using its wild as well as tissue-cultured plantlets to decolorize Brilliant Blue G (BBG) dye, a sample of dye mixture and a real textile effluent. In vitro cultures of P. grandiflora were obtained by seed culture method. The decolorization experiments were carried out using wild as well as tissue-cultured plants independently. The enzymatic analysis of the plant roots was performed before and after decolorization of BBG. Metabolites formed after dye degradation were analyzed using UV–vis spectroscopy, high-performance liquid chromatography, Fourier transform infrared spectroscopy, and gas chromatography–mass spectrometry. Phytotoxicity studies were performed. Characterization of dye mixture and textile effluent was also studied. The wild and tissue-cultured plants of P. grandiflora showed the decolorized BBG up to 86 %. Significant increase in the activities of lignin peroxidase, laccase, NADH-2,6-dichlorophenol-indophenol reductase, and tyrosinase was found in the roots of the plants. Three metabolites of BBG were identified as 3-{[ethyl(phenyl)amino]methyl}benzenesulfonic acid, 3-{[methyl (phenyl)amino]methyl}benzenesulfonic amino acid, and sodium-3-[(cyclohexa-2,5-dien-1-ylideneamino)methyl]benzenesulfonate. Textile effluent sample and a synthetic mixture of dyes were also decolorized by P. grandiflora. Phytotoxicity test revealed the nontoxic nature of metabolites. P. grandiflora showed the potential to decolorize and degrade BBG to nontoxic metabolites. The plant has efficiently treated a sample of dye mixture and textile effluent.     

Charismatic leadership and follower effects

On the basis of the current theories of charismatic leadership, several possible follower effects were identified. It is hypothesized that followers of charismatic leaders could be distinguished by their greater reverence, trust, and satisfaction with their leader and by a heightened sense of collective identity, perceived group task performance, and feelings of empowerment. Using the Conger–Kanungo charismatic leadership scale and measures of the hypothesized follower effects, an empirical study was conducted on a sample of 252 managers using structural equation modelling. The results show a strong relationship between follower reverence and charismatic leadership. Follower trust and satisfaction, however, are mediated through leader reverence. Followers' sense of collective identity and perceived group task performance are affected by charismatic leadership. Feelings of empowerment are mediated through the followers' sense of collective identity and perceived group task performance. Copyright © 2000 John Wiley & Sons, Ltd.     

Enhanced enzymatic removal of anthracene by the mangrove soil-derived fungus, Aspergillus sydowii BPOI

• A. sydowii strain bpo1 exhibited 99.8% anthracene degradation efficiency. • Four unique metabolic products were obtained after anthracene degradation. • Ligninolytic enzymes induction played vital roles in the removal of anthracene. • Laccase played a crucial role in comparison with other enzymes induced. The present study investigated the efficiency of Aspergillus sydowii strain bpo1 (GenBank Accession Number: MK373021) in the removal of anthracene (100 mg/L). Optimal degradation efficiency (98.7%) was observed at neutral pH, temperature (30℃), biomass weight (2 g) and salinity (0.2% w/v) within 72 h. The enzyme analyses revealed 131%, 107%, and 89% induction in laccase, lignin peroxidase, and manganese peroxidase respectively during anthracene degradation. Furthermore, the degradation efficiency (99.8%) and enzyme induction were significantly enhanced with the addition of 100 mg/L of citric acid and glucose to the culture. At varying anthracene concentrations (100–500 mg/L), the degradation rate constants (k₁) peaked with increasing concentration of anthracene while the half-life (t_1/2) decreases with increase in anthracene concentration. Goodness of fit (R² = 0.976 and 0.982) was observed when the experimental data were subjected to Langmuir and Temkin models respectively which affirmed the monolayer and heterogeneous nature exhibited by A. sydwoii cells during degradation. Four distinct metabolites; anthracene-1,8,9 (2H,8aH,9aH)-trione, 2,4a-dihydronaphthalene-1,5-dione, 1,3,3a,7a-tetrahydro-2-benzofuran-4,7-dione and 2-hydroxybenzoic acid was obtained through Gas Chromatography-Mass spectrometry (GC-MS). A. sydowii exhibited promising potentials in the removal of PAHs.     

The latent structure of landscape perception: A mean and covariance structure modeling approach

Mean and covariance structure (MACS) modeling is used to explore a central question in contemporary environmental psychology: “How should human environments be conceptualized?”. Specifically, an expanded version of the preference model of landscape perception proposed by S. and R. Kaplan is presented. The proposed model not only constitutes a respecification and deepening of the Kaplans’ model but also presents an integrative perspective that simultaneously considers the interrelations among cognitive, motivational, affective, evaluative, and behavioral tendencies in landscape perception. In a series of four studies, we develop and validate multi-item measures of various constructs, test the measure invariances, and the structural model. The findings reveal the crucial role of various constructs that originally were hypothesized by the Kaplans but never included in the model tests. In addition, positive and negative feelings induced by the landscape emerge as antecedents to landscape perception. The implications of these findings are discussed.     

旅游对尼泊尔珠穆朗玛峰国家公园步行道的影响

本文总结了在尼泊尔珠穆朗玛峰国家公园所做的旅游影响的研究结果,调查了旅游利用和环境特点对步行道的影响.7条步行道分成208个路段,评估的总长度为90km.采用了4级评估体系对步行道的路况进行评价,用Arc/Info和Arc/View地理信息系统(GIS)对旅游利用影响的空间格局进行分析.研究表明旅游利用和道路破坏之间密切相关,但步行道位置和环境因素是同等重要的变量.本研究认为较系统、实验性的研究是必要的,这些工作能够将人类活动导致的步行道损坏和自然因素影响明确地区别开.     

Quality of water obtained by tapping shallow seepages in the Almota Hills,India

We studied the quality of water obtained using a new method of tapping underground water seepages by digging shallow water collection chambers in the Almora Hills of the state of Uttar Pradesh, India; quality of this water was compared with that of water obtained using traditional water sources in this region, namely naulas (surface seepages) and springs.Water from both the new and the traditional water sources had an excess of chromium and, in some samples, of iron and lead. Microbiological analysis showed that water from new water sources was safer than that obtained from tradional sources; however, only 40% of the shallow seepages provided water conforming to WHO standards on water quality.We conclude that tapping of underground water seepages may be a useful method of providing potable water to populations living in the hills. However, further improvement is necessary in the maintenance of the clean catchment area and in disposal of waste water from these water sources to ensure water quality.     

Role of traditional conservation practice: highlighting the importance of Shivbari sacred grove in biodiversity conservation

Recognizing the importance of sacred groves in biodiversity conservation and management, and the recent threats to them, the present study was conducted in Shivbari sacred grove of Himachal Pradesh. The study aimed at documenting the floral wealth of Shivbari and promoting plantation of indigenous species in participation with local people. For this, systematic field surveys in different seasons were conducted in Shivbari from April 2005 to November 2009, and liaison was maintained with the local community and temple management authority for gaining insight into the history and problems of Shivbari and initiating plantation activities. A total of 69 flowering plant species were identified inside the grove, which include 14 trees, 9 shrubs, 3 lianas and 43 herbs. This represents almost 2% of the total flowering plant species occurring in the state of Himachal Pradesh. Mallotus philippensis followed by Putranjiva roxburghii was the most dominant tree species. Adhatoda zeylanica was the most common shrub species, while Achyranthes aspera was the most common herb species. The grove harbours 23 plants species that are in high demand in the market, and at the same time also influences the microclimate of the area. The temperature inside the grove was significantly lower than the temperature outside the grove. The recent changes in socio-economic status of the local people and a shift towards market-oriented economy have threatened the survival of Shivbari. However, the deeply held beliefs of the pilgrims, local people and priest offer a ray of hope. During the course of the study, 3,000 plants were planted inside the grove out of which 60% have survived.     

Physiological and metabolic effect of mercury accumulation in higher plants system

Heavy metals, lead (Pb) and mercury (Hg) are non-essential elements. Plants absorb these metals from soil, water and air through their roots and leaves. Heavy metals are the major environmental pollutants, which spread to soil through the use of pesticides, herbicides and micronutrient fertilizers, industrial effluents, decay of junk materials and sewage sludge, vehicular emissions, re-suspended road dust, diesel generator sets and coal-based thermal power plants. Sewage and sludge have contributed to heavy metal contamination of peri-urban lands and vegetable crops. The present review focuses on the effects of various concentrations of Hg on growth of young and mature seedlings as well as on nitrate reductase activity and nitrate assimilation in intact and excised seedling, especially the mechanism underlying nitrate reductase regulation by this heavy metal. Evidence indicates that mercury exerts significant adverse effects on the physiological activity of plants.     

Effect of complete and skeleton photoperiods in baya weaver, Ploceus philippinus

A study was performed to investigate the effects of complete and skeleton photoperiods on gonadal stimulation in baya weaver, Ploceus philippinus. In August 2003, five groups of acclimatized birds (n = 7 each) were exposed to 6L: 13D: 1L: 4D, 6L: 6D: 1L: 11D, 11L: 13D and 13L: 11D. Birds were refractory and their exposure to 6L:13D:1L:4D, 6L:6D:1L:11D, 11L:13D and 13L:11D did not evoke any response. This clearly indicates that the birds were insensitive to the stimulatory effects of these photoperiods and perceived them as short days. An attempt was made to test the responsivity by subjecting all these groups to long day exposure after 16 weeks of experiment. Under 16L: 8D, birds did not show a response during the first 4 weeks of exposure (week 16 to week 20), but thereafter there was a significant photoinduction except 11L:13D (week 24), but the rate and magnitude was different. Until the end of the experiment (32 weeks), all groups of birds had maximum testicular volume except 11L:13D. Birds pre-exposed to 6L:13D:1L:4D, 6L:6D:1L:11D, 11L:13D and 13L:11D responded to 16L:8D, which suggests that these photoperiods helped the birds in recovering their photosensitivity. The results from this experiment indicate that baya weaver interprets a light period depending when the light falls relative to its endogenous circadian system.