Rheological and fractal characteristics of unconditioned and conditioned water treatment residuals

The rheological and fractal characteristics of raw (unconditioned) and conditioned water treatment residuals (WTRs) were investigated in this study. Variations in morphology, size, and image fractal dimensions of the flocs/aggregates in these WTR systems with increasing polymer doses were analyzed. The results showed that when the raw WTRs were conditioned with the polymer CZ8688, the optimum polymer dosage was observed at 24 kg/ton dry sludge. The average diameter of irregularly shaped flocs/aggregates in the WTR suspensions increased from 42.54 μm to several hundred micrometers with increasing polymer doses. Furthermore, the aggregates in the conditioned WTR system displayed boundary/surface and mass fractals. At the optimum polymer dosage, the aggregates formed had a volumetric average diameter of about 820.7 μm, with a one-dimensional fractal dimension of 1.01 and a mass fractal dimension of 2.74 on the basis of the image analysis. Rheological tests indicated that the conditioned WTRs at the optimum polymer dosage showed higher levels of shear-thinning behavior than the raw WTRs. Variations in the limiting viscosity (η(∞)) of conditioned WTRs with sludge content could be described by a linear equation, which were different from the often-observed empirical exponential relationship for most municipal sludge. With increasing temperature, the η(∞) of the raw WTRs decreased more rapidly than that of the raw WTRs. Good fitting results for the relationships between lgη(∞)∼T using the Arrhenius equation indicate that the WTRs had a much higher activation energy for viscosity of about 17.86-26.91 J/mol compared with that of anaerobic granular sludge (2.51 J/mol) (Mu and Yu, 2006). In addition, the Bingham plastic model adequately described the rheological behavior of the conditioned WTRs, whereas the rheology of the raw WTRs fit the Herschel-Bulkley model well at only certain sludge contents. Considering the good power-law relationships between the limiting viscosity and sludge content of the conditioned WTRs, their mass fractal dimensions were calculated through the models proposed by Shih et al. (1990), which were 2.48 for these conditioned WTR aggregates. The results demonstrate that conditioned WTRs behave like weak-link flocs/aggregates.

Broken even-odd symmetry in self-selection of distances between nanoclusters due to the presence or absence of topological solitons

Depositing particles randomly on a 1D lattice is expected to result in an equal number of particle pairs separated by even or odd lattice units. Unexpectedly, the even-odd symmetry is broken in the self-selection of distances between indium magic-number clusters on a Si(100)-2×1 reconstructed surface. Cluster pairs separated by even units are less abundant because they are linked by silicon atomic chains carrying topological solitons, which induce local strain and create localized electronic states with higher energy. Our findings reveal a unique particle-particle interaction mediated by the presence or absence of topological solitons on alternate lattices.

Prolactin-releasing peptide mRNA expression in mouse medulla remains relatively stable during pregnancy and lactation

We compared levels of prolactin-releasing peptide (PrRP) mRNA expression in mouse medulla at different stages of pregnancy and lactation. Mouse medulla samples were collected on days 6, 12 and 18 of pregnancy and lactation, respectively (six per group), for mRNA. Expression levels of PrRP mRNA in the medulla were measured by semi-quantitative RT-PCR, with glyceraldehyde 3-phosphate dehydrogenase as a control. PrRP mRNA was highly expressed in mouse medulla oblongata on day 6 of pregnancy (0.53), followed by 0.43 at lactation day 6, and 0.42 at lactation day 12. The expression level of PrRP mRNA on days 12 and 18 of pregnancy and day 18 of lactation shared the same value of 0.36. PrRP mRNA levels during lactation decreased slightly compared with that during pregnancy, but the differences between them were not significant. In summary, PrRP mRNA levels in the medulla oblongata remain relatively stable during pregnancy and lactation. This is evidence that medulla PrRP is not involved in the regulation of prolactin secretion.

[A coal mine and coal preparation plant coal dust workplace present situation investigation and analysis]

OBJECTIVE

Through a detection of dust in the coal mines workplace, to understand the status of occupational hazards, and the evaluation of occupational hazards, provide subject to control occupational hazards.

METHOD

According to production process and "hazardous substances in workplace air monitoring, sampling norms" and other standards to determine the sampling points and sampling of coal dust.

RESULT

Underground mining operations in 21 subjects with time-weighted average concentration of dust types pass rate of 28.6%, of which five types of dust hazard grade II, six types of dust hazard rating of 0, and the remaining types of grade I dust hazard levels. Coal dust test six types of time-weighted average concentration of 83.3% pass rate, only one types of dust hazard grade I, all the rest is 0. Calculated by the detection of dust overrun 18 times operating sites, the pass rate of 72.2% results.

CONCLUSION

Purified water spray and air flow curtain of dust control has played a certain role, but the work of underground working conditions and environmental constraints, most of the dust concentration in workplace occupational exposure limits do not meet the requirements, recommended the strengthening of dust or Dust the daily management and maintenance of equipment, strengthen the ventilation, personal protection officers to strengthen operations.

Safety of a non-viral plasmid-encoding dual isoforms of hepatocyte growth factor in critical limb ischemia patients: a phase I study

We aimed to evaluate in a phase I dose-escalation study, the safety of intramuscular injections of a novel non-viral plasmid DNA expressing two isoforms of human hepatocyte growth factor (HGF) (VM202) in patients with critical limb ischemia (CLI). In total, 12 patients with CLI and unsuitable for revascularization were consecutively assigned to increasing doses (2 to 16 mg) of VM202 administered into the ischemic calf muscle at days 1 and 15. Patients were evaluated for safety and tolerability, changes in ankle- and toe brachial index (ABI and TBI), and pain severity score using a visual analog scale (VAS) throughout a 12-month follow-up period. Median age was 72 years and 53% of the patients were male. VM202 was safe and well tolerated with no death during the 12-month follow-up. Median ABI and TBI significantly increased from 0.35 to 0.52 (P=0.005) and from 0.15 to 0.24 (P=0.01) at 12 months follow-up. Median VAS decreased from 57.5 to 16.0 mm at 6 months follow-up (P=0.03). In this first human clinical trial, VM202, which expresses two isoforms of human HGF, appear to be safe and well tolerated with encouraging clinical results and thus supports the performance of a phase II randomized controlled trial.

Identification and determination of flavonoids in astragali radix by high performance liquid chromatography coupled with DAD and ESI-MS detection

A method for the analysis of flavonoids in Astragali Radix by high-performance liquid chromatography (HPLC) combined with photodiode-array detection (DAD) and an electrospray ionization (ESI) - mass spectrometry (MS) was developed. After the samples were extracted with ethanol, the optimum separation conditions for these analytes were achieved using a gradient elution system and a 2.0 × 150 mm Shimadzu VP-ODS column. Eight flavonoids were identified to exist in Astragali Radix based on their characteristic UV data and mass spectra. The concentrations of three major components in this herb—ononin, calycosin and formononetin—were determined by LC/ESI-MS in positive selective ion monitoring (SIM) mode. The calibration curves were linear in the range of 0.9~180.0 μg·mL⁻¹ for ononin, 1.8~360.0 μg·mL⁻¹ for calycosin and 1.4~280 μg·mL⁻¹ for formononetin, respectively. The limits of quantification (LOQ) and detection (LOD) were 0.9 μg· mL⁻¹ and 0.2 μg mL⁻¹ for ononin, 1.8 μg mL⁻¹ and 0.5 μg·mL⁻¹ for calycosin, 1.4 μg mL⁻¹ and 0.5 μg·mL⁻¹ for formononetin, respectively. The standard recoveries were between 95.4~104.7%. The developed method was proven to be useful for the quantitative and qualitative analysis of flavonoid constituents in various resources of Astragali Radix.

Risk perceptions and preparedness of typhoon disaster on coastal inhabitants in China

China is highly vulnerable to natural disasters. Southeastern China situated on the Pacific Ocean experiences severe and devastating typhoons and hydrogeological disasters every year. Although respondents are highly aware of the typhoon outbreaks, they do not have necessary precautionary actions. This retrospective study evaluates the inhabitants' sociodemographic characteristics with risk perceptions and preparedness. Subjects (434 adults) were recruited from two rural areas in coastal south-eastern China, both with high typhoon exposure. One area (landfall area [LA]) was more severely affected than the other (surrounding area [SA) by the 2006 typhoon "Saomai." Subjects were interviewed using a structured questionnaire with items addressing sociodemographic characteristics and exposure to public education related to emergency preparedness, risk perception, and coping strategies. Overall, most residents (92 percent) were aware that they lived in a high-risk area. About 54.6 percent respondents chose media as the first approach to obtain preparedness education, and 32.4 percent of respondents thought that personal experience is an important tool to defend themselves from typhoon. In LA, residents perceived themselves to be at higher risk than those who lived in the SA. More than 66.5 percent of respondents were terrified by typhoon, and 62.2 percent of respondents were afraid of its recurrence. Respondents emphasized that their life style (61.4 percent), property losses (54.5 percent), and threat to life (52.4 percent) were influenced by typhoon attack. Coping behavior most likely to be adopted was "anticipatory food, water storage and residents in LA is significantly higher than SA (p < 0.01). Risk perception with Spider Map analysis depicted that the item of disaster information is similar in both familiarity or dread associated with the risk axes (p > 0.05). However, in rescue and recovery of typhoon items, the score of familiarity with risk and dread with the risk axes is below 2.5. Regression analyses indicated that poor coping behavior was positively associated with age, risk perception, residential location, and knowledge of preparedness. The results indicated that risk perceptions and precaution activity were strongly related with inhabitants' sociodemographic characteristics and vulnerability of disaster-affected zone.

Analysis of the interactions of multicomponents in Cornus officinalis Sieb. et Zucc. with human serum albumin using on-line dialysis coupled with HPLC

Interactions of three iridoid glycosides extracted from Cornus officinalis Sieb. et Zucc. (CIG) with protein were simultaneously explored by on-line dialysis sampling coupled with high-performance liquid chromatography (DS-HPLC). Three main compounds in CIG were unequivocally identified as loganin, sweroside and cornuside by comparing their t(R), MS data and UV spectra with those of reference compounds. Dialysis recoveries and quantitative characteristics of DS-HPLC for three iridoid glycosides were determined. Recoveries of dialysis sampling ranged from 73.9 to 91.7% with the RSD below 3.0%. Based on the determination of concentrations before and after interaction with human serum albumin (HSA), the binding parameters of loganin, sweroside and cornuside with HSA were obtained and the binding mechanisms were investigated.

First Report of Anthracnose of Digitaria sanguinalis Caused by Colletotrichum hanaui in China

Hairy crabgrass (Digitaria sanguinalis (L.) Scop.) is a troublesome weed in most agricultural crops worldwide. Considerable efforts are made to limit the invasiveness and impact of crabgrass on crop productivity, including evaluation of fungi as biocontrol agents (3). In September 2005, a severe disease was observed on crabgrass plants in Zhejiang Province. Leaves and stems of the affected plant showed small, water-soaked, brownish spots that rapidly turned into longitudinal elliptic or spindle-shaped lesions, 6.5 to 8 × 22 to 24 mm, with a brown outer edge and a gray sunken central area. Coalescence of large lesions gave rise to extensive rotting and necrosis, and the stems were broken when the lesions encircled. Acervuli with brown setae and falcate single-celled spores, typical of some Colletotrichum species (2), formed on the lesions at this late stage. One fungal isolate (Col-68) was obtained from symptomatic tissues on potato dextrose agar that led to white-to-gray appressed mycelium growth with orange conidial masses at 28°C in darkness. Setae were septate, dark brown, rounded and sometimes lobed at base, 32.0 to 116.5 × 3.2 to 6.0 μm, with apices acute. Hyphae were septate, hyaline, 1.0 to 6.5 μm, and sometimes guttulate. Conidia were falcate or fusiform, apices acute or obtuse, and 8.16 to 26.37 × 2.9 to 9.2 μm with an average of 18.15 × 5.65 μm. Hyphopodial appressoria were smooth, globose to prolate, ovoid or obovoid with obtuse or cylindrical apices, edges entire, and 4.17 to 14.25 × 3.77 to 8.94 μm with an average of 7.0 × 6.9 μm. The pathogen was initially identified as a Colletotrichum species based on morphology. Suspensions of 3-day-old spores collected from potato dextrose liquid cultures (10⁶ conidia per ml) were used to spray inoculate (15 ml per pot) three 9-cm-diameter pots of crabgrass seedlings at the three- to four-leaf growth stage. Another three pots of healthy crabgrass were simultaneously sprayed with sterilized distilled water without conidia, which served as noninoculated checks. The seedlings were kept at 25 to 28°C for 24 h under a polyethylene sheet cover in the greenhouse. Symptoms that developed in all inoculated seedlings were identical to those observed on the affected crabgrass in the field, meanwhile the seedlings inoculated with sterilized water had no significant symptoms, and the reisolated strain had the same characteristics as the original isolate. To diagnose the pathogen to the species level, three isolates were tested and an approximately 580-bp DNA amplicon of this isolate was amplified using the primers ITS1/ITS4. The sequence (GenBank Accession No. GQ456160) had 98% sequence identity with the sequences of Colletotrichum hanaui (GenBank Accession Nos. EU554101and EU554124), which is supported by phylogenetic analysis with bootstrap support. On the basis of the morphological, pathological characteristics, and phylogenetic tree, the isolated strain was identified as C. hanaui (1). To our knowledge, this is the first confirmed report of anthracnose of D. sanguinalis caused by newly described C. hanaui in China. References: (1) J. A. Crouch et al. Mycologia, 101:717, 2009. (2) B. C. Sutton. The Coelomycetes. CAB International Publishing, New York, 1980. (3) Y. Z. Zhu and S. Qiang. Chin. J. Biol. Control 20:206, 2004.

The effect of high speed mixing and polymer dosing rates on the geometric and rheological characteristics of conditioned anaerobic digested sludge (ADS)

Wastewater sludges are non-Newtonian fluids because their shear rates change with shear stress and no linear relationship is observed between their shear stress and shear rate. Therefore, it is necessary to condition sludges with polyelectrolytes prior to dewatering to increase in the dewaterability. Since 1978, researchers have observed that the yield strength of conditioned sludge increased with the addition of polymer up to the optimum dose. Then sludge rheogram was used as a control parameter to optimize the addition of polymers, and the peak height in the shear stress vs. shear rate curve was an indication of sludge conditionablity, where the optimum polymer conditioning corresponding to the highest peak was obtained. However, few studies have addressed the effects of distinct conditioning factors on the appearance of peaks in such rheograms. In this study, the impact of factors such as high speed mixing and polymer dosing rates on the geometric and rheological characteristics of conditioned anaerobic digested sludge (ADS) with the polymer zetag7557 were investigated through the jar test method. The results showed that both the high speed mixing time and polymer dosing time had important effects on the emergence of the initial peak in test curves obtained using the Haake RV20 and Flokky rheometers for evaluation of conditioned ADS. A high speed mixing time within 60 s or a polymer dosing time of 5 s was sufficient for observation of the initial peak in flow curves, and both peak height and area decreased as the high speed mixing times were prolonged in most cases in this study. As same as the high speed mixing time, the extension of zetag7557 dosing time can also lead to the gradual decrease in the initial peak size of test curves, and form small aggregates with a decrease in two-dimensional fractal dimensions (D(2)). Although the initial peak in the test curves was observed when high speed mixing intensities increased up to 300 rpm, there were several differences in the peak height and area observed on the Haake RV20 test rheograms and Floccky test curves. In addition, a high speed mixing intensity of 300 rpm was found to lead to the formation of smaller and less compact aggregates than other mixing intensities. All of the rheological and geometric parameters were somewhat correlated with fractal dimension-D(2P) (based on regression analysis of the logarithmics of area and perimeter). However, D(2L)(based on regression analysis of the logarithmics of area and maximum diameter) did not show good correlation with any other parameters. The median diameters of the aggregates were well correlated with one-dimensional fractal dimensions (D(1)).

Cobra CRISP functions as an inflammatory modulator via a novel Zn2+- and heparan sulfate-dependent transcriptional regulation of endothelial cell adhesion molecules

Cysteine-rich secretory proteins (CRISPs) have been identified as a toxin family in most animal venoms with biological functions mainly associated with the ion channel activity of cysteine-rich domain (CRD). CRISPs also bind to Zn(2+) at their N-terminal pathogenesis-related (PR-1) domain, but their function remains unknown. Interestingly, similar the Zn(2+)-binding site exists in all CRISP family, including those identified in a wide range of organisms. Here, we report that the CRISP from Naja atra (natrin) could induce expression of vascular endothelial cell adhesion molecules, i.e. intercellular adhesion molecule-1, vascular adhesion molecule-1, and E-selectin, to promote monocytic cell adhesion in a heparan sulfate (HS)- and Zn(2+)-dependent manner. Using specific inhibitors and small interfering RNAs, the activation mechanisms are shown to involve both mitogen-activated protein kinases and nuclear factor-κB. Biophysical characterization of natrin by using fluorescence, circular dichroism, and x-ray crystallographic methods further reveals the presence of two Zn(2+)-binding sites for natrin. The strong binding site is located near the putative Ser-His-Glu catalytic triad of the N-terminal domain. The weak binding site remains to be characterized, but it may modulate HS binding by enhancing its interaction with long chain HS. Our results strongly suggest that natrin may serve as an inflammatory modulator that could perturb the wound-healing process of the bitten victim by regulating adhesion molecule expression in endothelial cells. Our finding uncovers a new aspect of the biological role of CRISP family in immune response and is expected to facilitate future development of new therapeutic strategy for the envenomed victims.

mRNA abundance and expression of SLC27A, ACC, SCD, FADS, LPIN, INSIG, and PPARGC1 gene isoforms in mouse mammary glands during the lactation cycle

The functions of distinct isoforms of solute carrier family 27 transporters (SLC27A1-6), acetyl-CoA carboxylase (ACACA, ACACB), stearoyl-CoA desaturase (SCD1-4), fatty acid desaturase (FADS1-3), LPIN (LPIN1-3), insulin-induced gene (INSIG1, 2), and peroxisome proliferator-activated receptor gamma coactivator1 (PPARGC1A, B) were studied in the mouse mammary gland from pregnancy to lactation. The relative mRNA abundance and percent change in real-time PCR were determined. mRNA expression of SLC27A3 and SLC27A4 was 37- and 1.4-fold more upregulated at 12 days of lactation, respectively (P < 0.01). Transcripts of SCD isoforms were the most abundant, accounting for 59% of all genes measured, and PPARGC1 isoforms were the least (0.06% of all genes measured). The mRNA abundance from ACC, FADS and LPIN accounted for 29, 9 and 2.6%, respectively. INSIG1 mRNA expression was 32-fold more upregulated (P < 0.05), while PPARGC1B was 0.18-fold downregulated at 18 days of lactation (P < 0.01). We concluded that mRNA abundance and expression of these isoforms are affected by the stage of lactation.

Determination of the volatile constituents in radix Flemingiae Philippinensis by GC-MS and a heuristic evolving latent projection method

With the help of chemometric resolution methods, a technique for qualitative and quantitative determination of the volatile chemical constituents in radix Flemingiae Philippinensis by chromatography-mass spectrometry was developed. After the overlapping chromatographic peaks were resolved into pure chromatograms and spectra using a heuristic evolving latent projections (HELP) method, qualitative analysis was performed by similarity search of the obtained pure mass spectrum of each component in the NIST library and the quantitative results were obtained by calculating the total two-way response volume. A total of 63 components were separated and 55 components were identified, accounting for 90.62% of the total content. The main components were farnesol isomer and beta-caryophyllene, accounting for 31.33% and 12.60% of the total content, respectively. The obtained results can provide useful information for further study and development of radix Flemingiae Philippinensis.

Selection and use of reference genes in mouse mammary glands

Obtaining quantitative data concerning gene expression is important for understanding milk synthesis in mammary glands. Quantitative real-time PCR (qRT-PCR) is an efficient tool to calculate gene expression; however, it is necessary to find valid reference genes for normalization of qRT-PCR data. We applied the geNorm software to eight commonly used reference genes to identify the most stable and optimal genes for the mouse mammary gland. Based on this analysis, HPRT, RPL and GAPDH are the most appropriate reference genes for data normalization. We tested the expression of the alpha-lactalbumin and fatty acid synthase genes using these three reference genes, both normalized and non-normalized. The normalized mRNA expression ratio was significantly different from the non-normalized ratio. We recommend the use of these three reference genes for the normalization of qRT-PCR data in gene expression studies of mouse mammary glands.