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1.
Horse heart carboxymethylated cytc (CM-cytc) displays myoglobin-like properties. Here, the effect of cardiolipin (CL) liposomes on the nitrite reductase activity of ferrous CM-cytc [CM-cytc-Fe(II)], in the presence of sodium dithionite, is reported between pH 5.5 and 7.6, at 20.0 °C. Cytc-Fe(II) displays a very low value of the apparent second-order rate constant for the NO2 ?-mediated conversion of cytc-Fe(II) to cytc-Fe(II)-NO [k on = (7.3 ± 0.7) × 10?2 M?1 s?1; at pH 7.4], whereas the value of k on for NO2 ? reduction by CM-cytc-Fe(II) is 1.1 ± 0.2 M?1 s?1 (at pH 7.4). CL facilitates the NO2 ?-mediated nitrosylation of CM-cytc-Fe(II) in a dose-dependent manner, the value of k on for the NO2 ?-mediated conversion of CL–CM-cytc-Fe(II) to CL–CM-cytc-Fe(II)-NO (5.6 ± 0.6 M?1 s?1; at pH 7.4) being slightly higher than that for the NO2 ?-mediated conversion of CL–cytc-Fe(II) to CL–cytc-Fe(II)-NO (2.6 ± 0.3 M?1 s?1; at pH 7.4). The apparent affinity of CL for CM-cytc-Fe(II) is essentially pH independent, the average value of B being (1.3 ± 0.3) × 10?6 M. In the absence and presence of CL liposomes, the nitrite reductase activity of CM-cytc-Fe(II) increases linearly on lowering pH and the values of the slope of the linear fittings of Log k on versus pH are ?1.05 ± 0.07 and ?1.03 ± 0.03, respectively, reflecting the involvement of one proton for the formation of the transient ferric form, NO, and OH?. These results indicate that Met80 carboxymethylation and CL binding cooperate in the stabilization of the highly reactive heme-Fe atom of CL–CM-cytc.  相似文献   

2.
The concentration of HCO 3 ? , pH, pO2, sO2, and pCO2 were measured in the total umbilical blood of neonates born in January–February (n = 169) and June–July (n = 172). The former group displayed higher values of pH, pO2, and sO2, whereas pCO2 and the concentration of HCO 3 ? were higher in the latter group. There was a 70–80% coincidence of the variants in both groups (the regions of statistical transgressions); seasonal factors were responsible for 20–30% of the differences.  相似文献   

3.
A Gram-stain negative, aerobic, motile by flagella, rod-shaped strain (THG-T16T) was isolated from rhizosphere of Hibiscus syriacus. Growth occurred at 10–40 °C (optimum 28–30 °C), at pH 6.0–8.0 (optimum 7.0) and at 0–1.0% NaCl (optimum 0%). Based on 16S rRNA gene sequence analysis, the near phylogenetic neighbours of strain THG-T16T were identified as Nibribacter koreensis KACC 16450T (98.6%), Rufibacter roseus KCTC 42217T (94.7%), Rufibacter immobilis CCTCC AB 2013351T (94.5%) and Rufibacter tibetensis CCTCC AB 208084T (94.4%). The DNA G+C content of strain THG-T16T was determined to be 46.7 mol%. DNA–DNA hybridization values between strain THG-T16T and N. koreensis KACC 16450T, R. roseus KCTC 42217T, R. immobilis CCTCC AB 2013351T, R.tibetensis CCTCC AB 208084T were 33.5?±?0.5% (31.7?±?0.7% reciprocal analysis), 28.1?±?0.2% (25.2?±?0.2%), 17.1?±?0.9% (10.2?±?0.6%) and 8.1?±?0.3% (5.2?±?0.1%). The polar lipids were identified as phosphatidylethanolamine, two unidentified aminophospholipids, an unidentified aminolipid and three unidentified lipids. The quinone was identified as MK-7 and the polyamine as sym-homospermidine. The major fatty acids were identified as C16:1 ω5c, C17:1 ω6c, iso-C15:0, summed feature 3 (C16:1 ω7c and/or C16:1 ω6c) and summed feature 4 (iso-C17:1 I and/or anteiso-C17:1 B). On the basis of the phylogenetic analysis, chemotaxonomic data, physiological characteristics, and DNA–DNA hybridization data, strain THG-T16T represents a novel species of the genus Nibribacter, for which the name Nibribacter flagellatus sp. nov. is proposed. The type strain is THG-T16T(=?KACC 19188T?=?CCTCC AB 2016246T).  相似文献   

4.
The purpose of this study was to investigate the short-term effects of maize (Zea mays)-fallow rotation, residue management, and soil water on carbon mineralization in a tropical cropping system in Ghana. After 15 months of the trial, maize–legume rotation treatments had significantly (P?C 0 (μg CO2–C g?1) than maize–elephant grass (Pennisetum purpureum) rotations. The C 0 for maize–grass rotation treatments was significantly related to the biomass input (r?=?0.95; P?=?0.05), but that for the maize–legume rotation was not. The soil carbon mineralization rate constant, k (per day), was also significantly related to the rotation treatments (P?k values for maize–grass and maize–legume rotation treatments were 0.025 and 0.036 day?1 respectively. The initial carbon mineralization rate, m 0 (μg CO2–C g?1 day ?1), was significantly (P?θ. The m 0 ranged from 3.88 to 18.67 and from 2.30 to 15.35 μg CO2–C g?1 day?1 for maize–legume and maize–grass rotation treatments, respectively, when the soil water varied from 28% to 95% field capacity (FC). A simple soil water content (θ)-based factor, f w, formulated as: \(f_{\text{w}} = \left[ {\frac{{\theta - \theta _{\text{d}} }}{{\theta _{{\text{FC}}} - \theta _{\text{d}} }}} \right]\), where θ d and θ FC were the air-dry and field capacity soil water content, respectively, adequately described the variation of the m 0 with respect to soil water (R 2?=?0.91; RMSE?=?1.6). Such a simple relationship could be useful for SOC modeling under variable soil water conditions.  相似文献   

5.
We studied extracellular acid phosphatase activity (AcPA) of planktonic microorganisms, aluminium (Al) speciation, and phosphorus (P) cycling in three atmospherically acidified (pH of 4.5–5.1) mountain forest lakes: ?ertovo jezero (CT), Prá?ilské jezero (PR), and Ple?né jezero (PL) in the Bohemian Forest (?umava, Böhmerwald). Microorganisms dominated pelagic food webs of the lakes and crustacean zooplankton were important only in PR, with the lowest Al concentrations (193 µg L?1) due to 3–4 times lower terrestrial input. The lakes differed substantially in Al speciation, i.e., in the proportion of ionic and particulate forms, with the highest proportion of ionic Al in the most acid CT (pH = 4.5). The P concentration in the inlet of PL (mean: 22.9 µg L?1) was about five times higher than in CT and PR (3.9 and 5.1 µg L?1, respectively). Average total biomass of planktonic microorganisms in PL (593 µg C L?1) was, however, only ~2-times higher than in CT and PR (235 and 272 µg C L?1, respectively). Enormous AcPA (means: 2.17–6.82 µmol L?1 h?1) and high planktonic C : P ratios suggested severe P limitation of the plankton in all lakes. Comparing 1998 and 2003 seasons, we observed changes in water composition (pH and Al speciation) leading to a significant increase in phytoplankton biomass in the lakes. The increase in the seston C : P ratio during the same time, however, indicates a progressive P deficiency of the lakes. The terrestrial Al inputs, together with in-lake processes controlling the formation of particulate Al, reduced P availability for planktonic microorganisms and were responsible for the differences in AcPA. At pH < 5, moreover, ionic Al forms caused inhibition of extracellular phosphatases. We postulate that both particulate and ionic Al forms affect P availability (i.e., inhibition of extracellular phosphatases and inactivation of P), specifically shape the plankton composition in the lakes and affect plankton recovery from the acid stress.  相似文献   

6.
The effect of percent relative humidity (16–84% RH), moisture content (4.2–6.5% w/w MC), and compression force (4.9–44.1 kN CF) on the light-induced fluorescence (LIF) response of 10% w/w active pharmaceutical ingredient (API) compacts is reported. The fluorescent response was evaluated using two separate central composite designs of experiments. The effect of % RH and CF on the LIF signal was highly significant with an adjusted R 2 ?=?0.9436 and p?<?0.0001. Percent relative humidity (p?=?0.0022), CF (p?<?0.0001), and % RH2 (p?=?0.0237) were statistically significant factors affecting the LIF response. The effects of MC and CF on LIF response were also statistically significant with a p value <0.0001 and adjusted R 2 value of 0.9874. The LIF response was highly impacted by MC (p?<?0.0001), CF (p?<?0.0001), and MC2 (p?=?0022). At 10% w/w API, increased % RH, MC, and CF led to a nonlinear decrease in LIF response. The derived quadratic model equations explained more than 94% of the data. Awareness of these effects on LIF response is critical when implementing LIF as a process analytical tool.  相似文献   

7.
A Gram-stain positive, aerobic, non-motile, endospore-forming and rod-shaped strain (THG-NT9T) was isolated from a green tea sample. Growth occurred at 20–45 °C (optimum 28–35 °C), at pH 6.0–8.0 (optimum 7.0) and at 0–2.0% NaCl (optimum 0%). Based on 16S rRNA gene sequence analysis, the near phylogenetic neighbours of strain THG-NT9T were identified as Scopulibacillus daqui DSM 28236T (98.6%), Scopulibacillus darangshiensis DSM 19377T (97.4%), Pullulanibacillus pueri CGMCC 1.12777T (96.7%) and Pullulanibacillus camelliae CGMCC 1.15371T (96.3%). The DNA G?+?C content of strain THG-NT9T was determined to be 47.5 mol %. DNA–DNA hybridization values between strain THG-NT9T and S. daqui DSM 28236T, S. darangshiensis DSM 19377T, P. pueri CGMCC 1.12777T, P. camelliae CGMCC 1.15371T and Pullulanibacillus naganoensis DSM 10191T were 41.3?±?0.1 (39.4?±?0.4% reciprocal analysis), 39.1?±?0.1 (37.3?±?0.1%), 21.4?±?0.7 (20.1?±?0.3%), 20.7?±?0.1 (20.1?±?0.4%) and 12.1?±?0.2% (8.3?±?0.2%). The polar lipids were identified as diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and three unidentified lipids. The quinone was identified as MK-7. The major fatty acids were C18:3 ω7c, iso-C15:0, iso-C16:0, iso-C17:0 and anteiso-C17:0. The cell wall type was determined to be A1γ peptidoglycan with meso-diaminopimelic acid as the diagnostic diamino acid plus alanine and glutamic acid and glucose as the cell wall sugar. On the basis of the phylogenetic analysis, chemotaxonomic data, physiological characteristics, and DNA–DNA hybridization data, strain THG-NT9T represents a novel species of the genus Scopulibacillus, for which the name Scopulibacillus cellulosilyticus sp. nov. is proposed. The type strain is THG-NT9T (=?KCTC 33918T?=?CGMCC 1.16305T).  相似文献   

8.
A Gram-stain negative, rod-shaped, non-motile, strictly aerobic bacterium HK-28T was isolated from a mangrove sediment sample in Haikou city, Hainan Province, China. Strain HK-28T was able to grow at 10–45 °C (optimum 25–30 °C), pH 5.0–8.5 (optimum 6.0–7.0) and 0.5–12.0% (w/v) NaCl (optimum 1.0–3.0%, w/v). The major cellular fatty acids were C16:0, Summed Feature 8 (C18:1 ω7c and/or C18:1 ω6c), Summed Feature 3 (C16:1 ω7c and/or C16:1 ω6c), C17:0, C12:0 3-OH and C17:1ω8c. Ubiquinone-8 (Q-8) was the predominant respiratory quinone. The polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, two unidentified aminophospholipids, four unidentified phospholipids, two unidentified glycolipid, an unidentified glycophospholipid, an unidentified aminolipid and an unidentified lipid. The DNA G+C content was 50.2 mol%. Accoroding to 16S rRNA gene sequence similarities, strain HK-28T shared 97.1 and 96.7% sequence similarities to the validly named species Gallaecimonas xiamenensis MCCC 1A01354T and Gallaecimonas pentaromativorans MCCC 1A06435T, respectively, and shared lower sequence similarities (<?92.0%) to all other genera. Phylogenetic analysis showed strain HK-28T was clustered with G. pentaromativorans MCCC 1A06435T and G. xiamenensis MCCC 1A01354T. Strain HK-28T showed low DNA–DNA relatedness with G. xiamenensis MCCC 1A01354T (28.3?±?1.5%) and G. pentaromativorans MCCC 1A06435T (25.2?±?2.4%). On the basis of phenotypic, chemotaxonomic and genotypic characteristics, strain HK-28T is considered to represent a novel species in the genus Gallaecimonas, for which the name Gallaecimonas mangrovi sp. nov. is proposed. The type strain is HK-28T (=?KCTC 62177T?=?MCCC 1K03441).  相似文献   

9.
Aquatic vegetation of Hydrochari-Lemnetea and Potametea classes in the Danube-Tisza-Danube hydrosystem (Hs DTD) was studied in 2009–2012, by applying the standard Braun-Blanquet method. The canal network vegetation comprises 14 associations, with Trapetum natantis and Ceratophylletum demersi being the most widely distributed. Hs DTD is also a habitat for several important endangered species, which serve as edificators of the following phytocenoses: Nymphaeetum albae, Nymphaeetum albo-luteae, Nymphoidetum peltatae, Trapetum natantis, Lemno-Spirodeletum, Salvinio-Spirodeletum polyrrhizae, Lemno-Utricularietum vulgaris, Potametum nodosi, Myriophyllo-Potametum and Najadetum marinae. In the studied vegetation, we also found an invasive phytocenosis Elodeetum canadensis that did not have an expanding tendency, and Ceratophyllo demersi-Vallisnerietum spiralis that had this tendency, which made monitoring its stands necessary. Physico-chemical analyses of water, conducted at localities in which the studied phytocenoses thrive, revealed that the development and distribution of most phytocenoses is closely linked with specific habitat conditions. Among the studied parameters, the most significant for the phytocenoses differentiation were: pH, alkalinity, COD-MnO4, BOD5, NO 3 ? , NO 2 ? , PO 4 3? and the concentration of total phosphorus.  相似文献   

10.

Objective

To characterize a novel xanthine dehydrogenase (XDH) from Acinetobacter baumannii by recombinant expression in Escherichia coli and to assess its potential for industrial applications.

Results

The XDH gene cluster was cloned from A. baumannii CICC 10254, expressed heterologously in E. coli and purified to homogeneity. The purified recombinant XDH consisted of two subunits with the respective molecular weights of 87 kDa and 56 kDa according to SDS-PAGE. XDH catalysis was optimum at pH 8.5 and 40–45 °C, was stable under alkaline conditions (pH 7–11) and the half-inactivation temperature was 60 °C. The K m, turnover number and catalytic efficiency for xanthine were 25 μM, 69 s?1 and 2.7 μM?1 s?1, respectively, which is an improvement over XDHs characterized previously. A. baumannii XDH is less than 50 % identical to previously identified XDH orthologs from other species, and is the first from the Acinetobacter genus to be characterized.

Conclusion

The novel A. baumannii enzyme was found to be among the most active, thermostable and alkaline-tolerant XDH enzymes reported to date and has potential for use in industrial applications.
  相似文献   

11.
12.
Laccases have received considerable attention in recent decades because of their ability to oxidise a large spectrum of phenolic and non-phenolic organic substrates and highly recalcitrant environmental pollutants. In this research, a laccase gene from Colletotrichum lagenarium was chemically synthesised using yeast bias codons and expressed in Pichia pastoris. The molecular mass of the recombinant laccase was estimated to be 64.6 kDa by SDS–PAGE, and the enzyme exhibited maximum activity at pH 3.6–4.0 but more stability in buffer with higher pH (>pH 3.6). The optimal reaction temperature of the enzyme was 40 °C, beyond which stability significantly decreased. By using 2,2′-azino-bis-(3-ethylbenzothiazoline)-6-sulphonate (ABTS) as a substrate, K m and V max values of 0.34 mM and 7.11 mM min?1 mg?1, respectively, were obtained. Using ABTS as a mediator, the laccase could oxidise hydroquinone to p-benzoquinone and decolourise the synthetic dyes malachite green, crystal violet and orange G. These results indicated that the laccase could be used to treat industrial effluents containing artificial dyes.  相似文献   

13.

Objective

To improve the production of trans-10,cis-12-conjugated linoleic acid (t10,c12-CLA) from linoleic acid in recombinant Yarrowia lipolytica.

Results

Cells of the yeast were permeabilized by freeze/thawing. The optimal conditions for t10,c12-CLA production by the permeabilized cells were at 28 °C, pH 7, 200 rpm with 1.5 g sodium acetate l?1, 100 g wet cells l?1, and 25 g LA l?1. Under these conditions, the permeabilized cells produced 15.6 g t10,c12-CLA l?1 after 40 h, with a conversion yield of 62 %. The permeabilized cells could be used repeatedly for three cycles, with the t10,c12-CLA extracellular production remaining above 10 g l?1.

Conclusion

Synthesis of t10,c12-CLA was achieved using a novel method, and the production reported in this work is the highest value reported to date.
  相似文献   

14.
A Nocardia-like actinobacterial strain, designated YIM TG2190T, was isolated from rhizosphere soil of Psammosilene tunicoides collected from Gejiu, Yunnan province, China. The cells of strain YIM TG2190T were observed to be Gram-stain positive and non-motile. The strain forms extensively branched substrate mycelia that fragments into rod-shaped elements. The 16S rRNA gene sequence analysis showed that strain YIM TG2190T is closely related to Nocardia nova (97.5%), Nocardia jiangxiensis (97.1%) and Nocardia miyunensis (96.8%). Growth occurs at 4–30?°C (optimum 28?°C), pH 6.0–8.0 (optimum pH 7.0) and the strain can tolerate NaCl (w/v) up to 3% (optimum 0–1%). The cell walls were found to contain meso-diaminopimelic acid. The whole-cell sugars were identified as glucose, mannose, ribose, galactose, arabinose and fucose. The polar lipids were identified as diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol mannosides, phosphatidylglycerol and an unidentified phospholipid. The menaquinones detected were MK-9 (H2) and MK-8 (H4). The major fatty acids (>?5%) were found to be C16:0 (33.9%), summed feature 3 (21.7%), C18:0 10-methyl TBSA (13.7%) and C18:1ω9c (7.0%). The DNA G+C content was determined to be 61.1 mol%. DNA-DNA relatedness between the strain YIM TG2190T and N. nova CGMCC 4.1705T, N. jiangxiensis CGMCC 4.1905T and N. miyunensis CGMCC 4.1904T were 46.9?±?2.6, 36.8?±?1.3, and 35.7?±?2.6%, respectively, values which are less than the threshold value (70%) for the delineation of prokaryotic genomic species. The phenotypic, chemotaxonomic and phylogenetic data indicates that strain YIM TG2190T represents a novel species of the genus Nocardia, for which the name Nocardia zhihengii sp. nov. is proposed. The type strain is YIM TG2190T (=KCTC 39596T?=?DSM 100515T).  相似文献   

15.
The aim of present study was to elucidate the association of CTLA4 +49 A/G and HLA-DRB1*/DQB1* gene polymorphism in south Indian T1DM patients. The patients and controls (n?=?196 each) were enrolled for CTLA4 and HLA-DRB1*/DQB1* genotyping by RFLP/PCR-SSP methods. The increased frequencies of CTLA4 ‘AG’ (OR?=?1.99; p?=?0.001), ‘GG’ (OR?=?3.94; p?=?0.001) genotypes, and ‘G’ allele (OR?=?2.42; p?=?9.26?×?10?8) were observed in patients. Reduced frequencies of ‘AA’ (OR?=?0.35; p?=?7.19?×?10?7) and ‘A’ (OR?=?0.41; p?=?9.26?×?10?8) in patients revealed protective association. Among HLA-DRB1*/DQB1* alleles, DRB1*04 (OR?=?3.29; p?=?1.0?×?10?5), DRB1*03 (OR?=?2.81; p?=?1.9?×?10?6), DQB1*02:01 (OR?=?2.93; p?=?1.65?×?10?5), DQB1*02:02 (OR?=?3.38; p?=?0.0003), and DQB1*03:02 (OR?=?7.72; p?=?0.0003) were in susceptible association. Decreased frequencies of alleles, DRB1*15 (OR?=?0.32; p?=?2.55?×?10?7), DRB1*10 (OR?=?0.45; p?=?0.002), DQB1*06:01 (OR?=?0.43; p?=?0.0001), and DQB1*05:02 (OR?=?0.28; p?=?2.1?×?10?4) in patients were suggested protective association. The combination of DRB1*03+AG (OR?=?5.21; p?=?1.4?×?10?6), DRB1*04+AG (OR?=?2.14; p?=?0.053), DRB1*04+GG (OR?=?5.21; p?=?0.036), DQB1*02:01+AG (OR?=?4.44; p?=?3.6?×?10?5), DQB1*02:02+AG (OR?=?20.9; p?=?9.5?×?10?4), and DQB1*02:02+GG (OR?=?4.06; p?=?0.036) revealed susceptible association. However, the combination of DRB1*10+AA (OR?=?0.35; p?=?0.003), DRB1*15+AA (OR?=?0.22; p?=?5.3?×?10?7), DQB1*05:01+AA (OR?=?0.45; p?=?0.007), DQB1*05:02+AA (OR?=?0.17; p?=?1.7?×?10?4), DQB1*06:01+AA (OR?=?0.40; p?=?0.002), and DQB1*06:02+AG (OR?=?0.34; p?=?0.001) showed decreased frequency in patients, suggesting protective association. In conclusion, CTLA4/HLA-DR/DQ genotypic combinations revealed strong susceptible/protective association toward T1DM in south India. A female preponderance in disease associations was also documented.  相似文献   

16.
In this study, we determined whether a prediction of final infarct volume (FIV) and clinical outcomes in patients with an acute stroke is improved by using a contrast transfer coefficient (K trans) as a biomarker for blood–brain barrier (BBB) dysfunction. Here, consecutive patients admitted with signs and symptoms suggesting acute hemispheric stroke were included in this study. Ninety-eight participants with intra-arterial therapy were assessed (46 female). Definition of predicted FIV was performed using conventional perfusion CT (PCT-PIV) parameters alone and in combination with K trans (K trans-PIV). Multiple logistic regression analyses and linear regression modeling were conducted to determine independent predictors of the 90-day modified Rankin score (mRS) and FIV, respectively. We found that patients with favorable outcomes were younger and had lower National Institutes of Health Stroke Scale (NIHSS) score, smaller PCT-PIV, K trans-PIV, and smaller FIV (P?<?0.001). K trans-PIV showed good correlation with FIV (P?<?00.001, R 2?=?0.6997). In the regression analyses, K trans-PIV was the best predictor of clinical outcomes (P?=?0.009, odds ratio (OR)?=?1.960) and also the best predictor for FIV (F?=?75.590, P?<?0.0001). In conclusion, combining PCT and K trans maps derived from first-pass PCT can identify at-risk cerebral ischemic tissue more precisely than perfusion parameters alone. This provides improved accuracy in predicting FIV and clinical outcomes.  相似文献   

17.

Objectives

To engineer Escherichia coli for the heterologous production of di-rhamnolipids, which are important biosurfactants but mainly produced by opportunistic pathogen Pseudomonas aeruginosa.

Results

The codon-optimized rhlAB and rhlC genes originating from P. aeruginosa and Burkholderia pseudomallei were combinatorially expressed in E. coli to produce di-rhamnolipids with varied congeners compositions. Genes involved in endogenous upstream pathways (rhamnose and fatty acids synthesis) were co-overexpressed with rhlABrhlC, resulting in variations of rhamnolipids production and congeners compositions. Under the shake-flask condition, co-overexpression of rfbD with rhlABrhlC increased rhamnolipids production (0.64 ± 0.02 g l?1) than that in strain only expressing rhlABrhlC (0.446 ± 0.009 g l?1), which was mainly composed of di-rhamnolipids congeners Rha–Rha–C10–C10.

Conclusion

Biosynthesis of di-rhamnolipids and variations of congeners composition in genetically engineered E. coli strains were achieved via combiniations of mono-/di-rhamnolipids synthesis modules and endogenous upstream modules.
  相似文献   

18.
Present study revealed the presence of 16 earthworm species belonging to 11 genera and four families viz. Megascolecidae (Amynthus alexandri, Metaphire houlleti, Lampito mauritii, Kanchuria sp1, Perionyx excavatus), Octochaetidae (Eutyphoeus gigas, Eutyphoeus comillahnus, Eutyphoeus orientalis, Octochaetona beatrix, Dichogaster bolaui, Lennogaster chittagongensis, Lennogaster yeicus), Moniligastridae (Drawida papillifer papillifer, Drawida assamensis, Drawida nepalensis) and Glossoscolecidae (Pontoscolex corethrurus) in the soils of five bamboo species [Bambusa balcooa (Sil Barak), Melocanna baccifera (Muli), Bambusa polumorpha (Bari), Bambus cacharensis (Bom) and Bambus bambus (Katabarak)] of West-Tripura. While four earthworm species viz. Metaphire houlleti, Drawida assamensis, Drawida papillifer papillifer and Pontoscolex corethrurus were common to all species of bamboo plantations, the rest showed restricted distribution. Among the earthworm species 4 were exotic (Amynthus alexandri, Metaphire houlleti, Dichogaster bolaui and Pontoscolex corethrurus) and the others were native to the Indian sub-continent. In general, earthworms under the bamboo plantations occurred within temperature range of 21.6 °C–28.0 °C, pH 4.0–7.0, organic matter 0.56–5.99 %, moisture 9.6–31.7 %, water holding capacity 14.6–43.9 % and bulk density 0.7–1.8 g cm?3. The average density and biomass of the earthworms in the studied places were 108 ind m?2 and 44 g m?2 respectively. Earthworm diversity, dominance and evenness indices showed the values 1.00, 0.47 and 0.70 respectively. Earthworm density and biomass showed a negative correlation with temperature whereas those had a strong positive correlation with pH, moisture and organic matter of the soils.  相似文献   

19.
Spray-dried ipratropium bromide (IPB) microspheres for oral inhalation were engineered using Quality by Design. The interrogation of material properties, process parameters, and critical product quality attributes interplay enabled rational product design. A 27–3 screening design exhibited the Maillard reaction between L-leucine (LL) and lactose at studied outlet temperatures (OT) >130°C. A response surface custom design was used in conjunction with multicriteria optimization to determine the operating design space to achieve inhalable microparticles. Statistically significant predictive models were developed for volume median diameter (p?=?0.0001, adjusted R 2? =?0.9938), span (p?=?0.0278, adjusted R 2? =?0.7912), yield (p?=?0.0020, adjusted R 2? =?0.9320), and OT (p?=?0.0082, adjusted R 2? =?0.8768). An independent verification batch confirmed the model’s predictive capability. The prediction and actual values were in good agreement. Particle size and span were 3.32?±?0.09 μm and 1.71?±?0.18, which were 4.7 and 5.3% higher than the predicted values. The process yield was 50.3%, compared to the predicted value of 65.3%. The OT was 100°C versus the predicted value of 105°C. The label strength of IPB microparticles was 99.0 to 105.9% w/w suggesting that enrichment occurred during the spray-drying process. The present study can be utilized to initiate the design of the first commercial IPB dry powder inhaler.  相似文献   

20.
In Moroccan Arabic, like in many other Afroasiatic languages, certain nouns may have more than one plural form. For instance, t ? es ? wera ‘photo’ has plurals t ? s ? awer and t ? s ? werat. However, their diminutive systematically resorts to -at suffixation in the plural. The aim of this study is twofold. First, it presents an interface approach which aims to determine the structural location of number and capture the empirical contrast between broken and sound plurals. It is argued that the sound plurals are associated with the standard Num projection, whereas the broken plurals are associated lower in the structure with the n projection. Second, it provides a templatic analysis of the diminutive formation, showing that the diminutive and the internal plural markers compete for the same templatic position. External evidence for the analysis is drawn from the phenomenon of emphasis spread. The nP is presented as the maximal domain of emphasis spread in nouns.  相似文献   

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