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1

Scanning Electron Microscopic study of Piper betle L. leaves extract effect against Streptococcus mutans ATCC 25175  

PubMed Central

Introduction Previous studies have shown that Piper betle L. leaves extract inhibits the adherence of Streptococcus mutans to glass surface, suggesting its potential role in controlling dental plaque development. Objectives: In this study, the effect of the Piper betle L. extract towards S. mutans (with/without sucrose) using scanning electron microscopy (SEM) and on partially purified cell-associated glucosyltransferase activity were determined. Material and Methods S. mutans were allowed to adhere to glass beads suspended in 6 different Brain Heart Infusion broths [without sucrose; with sucrose; without sucrose containing the extract (2 mg mL-1 and 4 mg mL-1); with sucrose containing the extract (2 mg mL-1 and 4 mg mL-1)]. Positive control was 0.12% chlorhexidine. The glass beads were later processed for SEM viewing. Cell surface area and appearance and, cell population of S. mutans adhering to the glass beads were determined upon viewing using the SEM. The glucosyltransferase activity (with/without extract) was also determined. One- and two-way ANOVA were used accordingly. Results It was found that sucrose increased adherence and cell surface area of S. mutans (p<0.001). S. mutans adhering to 100 µm2 glass surfaces (with/without sucrose) exhibited reduced cell surface area, fluffy extracellular appearance and cell population in the presence of the Piper betle L. leaves extract. It was also found that the extract inhibited glucosyltransferase activity and its inhibition at 2.5 mg mL-1 corresponded to that of 0.12% chlorhexidine. At 4 mg mL-1 of the extract, the glucosyltransferase activity was undetectable and despite that, bacterial cells still demonstrated adherence capacity. Conclusion The SEM analysis confirmed the inhibitory effects of the Piper betle L. leaves extract towards cell adherence, cell growth and extracellular polysaccharide formation of S. mutans visually. In bacterial cell adherence, other factors besides glucosyltransferase are involved. PMID:21552715

RAHIM, Zubaidah Haji Abdul; THURAIRAJAH, Nalina

2011-01-01

2

Investigations on Piper betle grown in Sri Lanka  

PubMed Central

Piper betle is an economically important plant cultivated in Sri Lanka. Although more than 12 cultivars of betel are reported in Sri Lanka, very few scientific investigations have been carried out on them. Studies on the chemical constituents indicated that safrole is the major constituent, followed by chavibitol acetate, in the essential oil of common betel leaves of Sri Lanka. Investigations on the bioactivities of P. betle revealed the presence of antimicrobial, insecticidal, antioxidant, antinociceptive, antidiabetic and gastroprotective activities. In addition, P. betle was found to be safe in terms of hepatotoxicity, renotoxicity, hematotoxicity, gross morphology, weights of organs, stress or aversive behaviors in rats. The above findings indicate the vast potential of P. betle yet to be harnessed for the benefit of mankind and the betel industry of Sri Lanka. PMID:22279373

Arambewela, L. S. R.; Arawwawala, L. D. A. M.; Kumaratunga, K. G; Dissanayake, D. S; Ratnasooriya, W. D.; Kumarasingha, S. P.

2011-01-01

3

Piper betle extracts exhibit antitumor activity by augmenting antioxidant potential  

PubMed Central

The present study was conducted to evaluate the methanolic extract of Piper betle leaves (MPBL) and its organic fractions with regard to antitumor activity against Ehrlich ascites carcinoma (EAC) in Swiss albino mice and to confirm their antioxidant activities. At 24 h post-intraperitoneal inoculation of tumor cells into mice, extracts were administered at 25, 50 and 100 mg/kg body weight for nine consecutive days. The antitumor effects of the extracts were then assessed according to tumor volume, packed cell count, viable and non-viable tumor cell count, median survival time and increase in life span of EAC-bearing mice. Next, hematological profiles and serum biochemical parameters were calculated, and antioxidant properties were assessed by estimating lipid peroxidation, reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) levels. MPBL and the ethylacetate fraction (EPBL) at a dose of 100 mg/kg induced a significant decrease in tumor volume, packed cell volume and viable cell count and increased the life span of the EAC-bearing mice (P<0.05). Hematological and serum biochemical profiles were restored to normal levels in the extract-treated mice compared with the EAC control mice. MPBL and EPBL treatment significantly decreased lipid peroxidation (P<0.05) and restored GSH, SOD and CAT levels towards normal compared with the EAC control. Taken together, the results of the present study demonstrated that Piper betle extracts exhibit significant antitumor activity, which may be attributed to the augmentation of endogenous antioxidant potential.

ALAM, BADRUL; MAJUMDER, RAJIB; AKTER, SHAHINA; LEE, SANG-HAN

2015-01-01

4

Ethnoveterinary study for antidermatophytic activity of Piper betle, Alpinia galanga and Allium ascalonicum extracts in vitro.  

PubMed

Crude ethanolic extracts of Piper betle leaves (Piperaceae), Alpinia galanga rhizomes (Zingiberaceae) and Allium ascalonicum bulbs (Liliaceae) were tested against selected zoonotic dermatophytes (Microsporum canis, Microsporum gypseum and Trichophyton mentagrophyte) and the yeast-like Candida albicans. A broth dilution method was employed to determine the inhibitory effect of the extracts and compared to those of ketoconazole and griseofulvin. All extracts suppressed the growth of the fungi in a concentration-dependent manner. Among the extracts tested, P. betle exhibited more effective antifungal properties with average IC(50) values ranging from 110.44 to 119.00 microg/ml. Subsequently, 10% Piper betle (Pb) cream was formulated, subjected to physical and microbial limit test and evaluated for antifungal effect. The disc diffusion assay revealed comparable zones of inhibition between discs of Pb cream containing 80 microg P. betle extract and 80 microg ketoconazole against tested fungi at 96 h after incubation. Thereafter, the inhibitory effect of Pb cream markedly decreased and completely lost effectiveness by day 7. In summary, the results supported the traditional wisdom of herbal remedy use and suggested a potential value-addition to agricultural products. It was suggested that the Pb cream has potential therapeutic value for treatment of dermatophytosis. However, clinical testing as well as improving the Pb cream formulation with greater efficacy and duration of action would be of interest and awaits further investigation. PMID:17482221

Trakranrungsie, N; Chatchawanchonteera, A; Khunkitti, W

2008-02-01

5

Role of chlorophyllase in chlorophyll homeostasis and post-harvest breakdown in Piper betle L. leaf.  

PubMed

Piper betle L., a dioecious shade-loving perennial climber is one of the important Pan-Asiatic plants. More than hundred landraces having marked variation in leaf chlorophyll (Chl) content are in cultivation in India. In this study, role of chlorophyllase (Chlase) in Chl homeostasis and post-harvest breakdown was investigated in two contrasting P. betle landraces Kapoori Vellaikodi (KV) with light green and Khasi Shillong (KS) with dark green leaves. The two landraces showed negative correlation between Chl content and Chlase activity in fresh as well as stored leaves. Accumulation of chlorophyllide a (Chlid a) was correlated with the level of Chlase activity, which was higher in KV than KS. The overall response of abscisic acid (ABA) and benzylaminopurine (BAP) was similar in KV and KS, however, the time-course was different. ABA-induced Chl loss was accompanied by rise in Chlase activity in KV and KS and the delay in Chl loss by BAP was accompanied by reduction in Chlase activity. While there were significant differences in Chlase activity in KV and KS, only minor differences were observed in the enzyme properties like pH and temperature optima, Km and Vmax. No landrace-related differences were observed on the effect of metal ions and functional group reagents/amino acid effectors on Chlase activity. These results showed that despite significant differences in Chl content and Chlase activity between landraces KV and KS, the properties of Chlase were similar. The findings show that in P. betle Chlase is involved in Chl homeostasis and also in Chl degradation during post-harvest storage and responds to hormonal regulations. These findings might be useful in predicting the stability of Chl during post-harvest storage and also the shelf-life in other P. betle landraces. PMID:22165295

Gupta, Supriya; Gupta, Sanjay Mohan; Kumar, Nikhil

2011-10-01

6

Chlorophyllase in Piper betle L. has a role in chlorophyll homeostasis and senescence dependent chlorophyll breakdown.  

PubMed

Total chlorophyll content and chlorophyllase (chlorophyll-chlorophyllido hydrolase EC 3.1.1.14) activity in fresh leaves of Piper betle L. landrace KS was, respectively, twofold higher and eight fold lower than KV, showing negative correlation between chlorophyll and chlorophyllase activity. Specific chlorophyllase activity was nearly eightfold more in KV than KS. ORF of 918 nt was found in cloned putative chlorophyllase cDNAs from KV and KS. The gene was present as single copy in both the landraces. The encoded polypeptide of 306 amino acids differed only at two positions between the KV and KS; 203 (cysteine to tyrosine) and 301 (glutamine to glycine). Difference in chlorophyllase gene expression between KV and KS was evident in fresh and excised leaves. Up regulation of chlorophyllase gene by ABA and down regulation by BAP was observed in both the landraces; however, there was quantitative difference between KV and KS. Data suggests that chlorophyllase in P. betle is involved in chlorophyll homeostasis and chlorophyll loss during post harvest senescence. PMID:22311037

Gupta, Supriya; Gupta, Sanjay Mohan; Sane, Aniruddha P; Kumar, Nikhil

2012-06-01

7

Piper betle-mediated green synthesis of biocompatible gold nanoparticles  

NASA Astrophysics Data System (ADS)

Here, we report the novel use of the ethonolic leaf extract of Piper betle for gold nanoparticle (AuNP) synthesis. The successful formation of AuNPs was confirmed by UV-visible spectroscopy, and different parameters such as leaf extract concentration (2%), gold salt concentration (0.5 mM), and time (18 s) were optimized. The synthesized AuNPs were characterized with different biophysical techniques such as transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), and energy-dispersive X-ray spectroscopy (EDX). TEM experiments showed that nanoparticles were of various shapes and sizes ranging from 10 to 35 nm. FT-IR spectroscopy revealed that AuNPs were functionalized with biomolecules that have primary amine group -NH2, carbonyl group, -OH groups, and other stabilizing functional groups. EDX showed the presence of the elements on the surface of the AuNPs. FT-IR and EDX together confirmed the presence of biomolecules bounded on the AuNPs. Cytotoxicity of the AuNPs was tested on HeLa and MCF-7 cancer cell lines, and they were found to be nontoxic, indicating their biocompatibility. Thus, synthesized AuNPs have potential for use in various biomedical applications.

Punuri, Jayasekhar Babu; Sharma, Pragya; Sibyala, Saranya; Tamuli, Ranjan; Bora, Utpal

2012-08-01

8

Piper nigrum, Piper betle and Gnetum gnemon--natural food sources with anti-quorum sensing properties.  

PubMed

Various parts of Piper nigrum, Piper betle and Gnetum gnemon are used as food sources by Malaysians. The purpose of this study is to examine the anti-quorum sensing (anti-QS) properties of P. nigrum, P. betle and G. gnemon extracts. The hexane, chloroform and methanol extracts of these plants were assessed in bioassays involving Pseudomonas aeruginosa PA01, Escherichia coli [pSB401], E. coli [pSB1075] and Chromobacterium violaceum CV026. It was found that the extracts of these three plants have anti-QS ability. Interestingly, the hexane, chloroform and methanol extracts from P. betle showed the most potent anti-QS activity as judged by the bioassays. Since there is a variety of plants that serve as food sources in Malaysia that have yet to be tested for anti-QS activity, future work should focus on identification of these plants and isolation of the anti-QS compounds. PMID:23519352

Tan, Li Ying; Yin, Wai-Fong; Chan, Kok-Gan

2013-01-01

9

Antihyperglycemic activity of Piper betle leaf on streptozotocin-induced diabetic rats.  

PubMed

Piper betle, an indigenous medicinal plant, has a folk (Siddha and Ayurvedha) reputation in the rural southern India. The present study was carried out to evaluate the effect of P. betle on glucose metabolism since it is consumed as betel-quid after meals. Plasma levels of glucose and glycosylated hemoglobin and activities of liver hexokinase and gluconeogenic enzymes such as glucose-6-phosphatase and fructose-1,6-bisphosphatase in control and streptozotocin (STZ) diabetic rats were assayed. Oral administration of leaf suspension of P. betle (75 and 150 mg/kg of body weight) for 30 days resulted in significant reduction in blood glucose (from 205.00 +/- 10.80 mg/dL to 151.30 +/- 6.53 mg/dL) and glycosylated hemoglobin and decreased activities of liver glucose-6-phosphatase and fructose-1,6-bisphosphatase, while liver hexokinase increased (P < .05), in STZ diabetic rats when compared with untreated diabetic rats. P. betle at a dose of 75 mg/kg of body weight exhibited better sugar reduction than 150 mg/kg of body weight. In addition, protection against body weight loss of diabetic animals was also observed. The effects produced by P. betle were compared with the standard drug glibenclamide. Thus, the present study clearly shows that P. betle intake influences glucose metabolism beneficially. PMID:16579737

Santhakumari, P; Prakasam, A; Pugalendi, K V

2006-01-01

10

Psidium guajava and Piper betle Leaf Extracts Prolong Vase Life of Cut Carnation (Dianthus caryophyllus) Flowers  

PubMed Central

The effect of leaf extracts of Psidium guajava and Piper betle on prolonging vase life of cut carnation flowers was studied. “Carola” and “Pallas Orange” carnation flowers, at bud stage, were pulsed 24 hours with a floral preservative. Then, flowers were placed in a vase solution containing sprite and a “germicide” (leaf extracts of P. guajava and P. betle, 8-HQC, or a copper coin). Flowers treated with 8-HQC, copper coin, and leaf extracts had longer vase life, larger flower diameter, and higher rate of water uptake compared to control (tap water). The leaf extracts of P. guajava and P. betle showed highest antibacterial and antifungal activities compared to the other treatments. Both showed similar effects on flower quality as the synthetic germicide, 8-HQC. Therefore, these extracts are likely natural germicides to prolong vase life of cut flowers. PMID:22619568

Rahman, M. M.; Ahmad, S. H.; Lgu, K. S.

2012-01-01

11

Psidium guajava and Piper betle leaf extracts prolong vase life of cut carnation (Dianthus caryophyllus) flowers.  

PubMed

The effect of leaf extracts of Psidium guajava and Piper betle on prolonging vase life of cut carnation flowers was studied. "Carola" and "Pallas Orange" carnation flowers, at bud stage, were pulsed 24 hours with a floral preservative. Then, flowers were placed in a vase solution containing sprite and a "germicide" (leaf extracts of P. guajava and P. betle, 8-HQC, or a copper coin). Flowers treated with 8-HQC, copper coin, and leaf extracts had longer vase life, larger flower diameter, and higher rate of water uptake compared to control (tap water). The leaf extracts of P. guajava and P. betle showed highest antibacterial and antifungal activities compared to the other treatments. Both showed similar effects on flower quality as the synthetic germicide, 8-HQC. Therefore, these extracts are likely natural germicides to prolong vase life of cut flowers. PMID:22619568

Rahman, M M; Ahmad, S H; Lgu, K S

2012-01-01

12

Piper betle shows antioxidant activities, inhibits MCF-7 cell proliferation and increases activities of catalase and superoxide dismutase  

PubMed Central

Background Breast cancer is the most common form of cancer and the focus on finding chemotherapeutic agents have recently shifted to natural products. Piper betle is a medicinal plant with various biological activities. However, not much data is available on the anti-cancer effects of P. betle on breast cancer. Due to the current interest in the potential effects of antioxidants from natural products in breast cancer treatment, we investigated the antioxidant activities of the leaves of P. betle and its inhibitory effect on the proliferation of the breast cancer cell line, MCF-7. Methods The leaves of P. betle were extracted with solvents of varying polarities (water, methanol, ethyl acetate and hexane) and their phenolic and flavonoid content were determined using colorimetric assays. Phenolic composition was characterized using HPLC. Antioxidant activities were measured using FRAP, DPPH, superoxide anion, nitric oxide and hyroxyl radical scavenging assays. Biological activities of the extracts were analysed using MTT assay and antioxidant enzyme (catalase, superoxide dismutase, glutathione peroxidase) assays in MCF-7 cells. Results Overall, the ethyl acetate extract showed the highest ferric reducing activity and radical scavenging activities against DPPH, superoxide anion and nitric oxide radicals. This extract also contained the highest phenolic content implying the potential contribution of phenolics towards the antioxidant activities. HPLC analyses revealed the presence of catechin, morin and quercetin in the leaves. The ethyl acetate extract also showed the highest inhibitory effect against the proliferation of MCF-7 cells (IC50=65 ?g/ml). Treatment of MCF-7 cells with the plant extract increased activities of catalase and superoxide dismutase. Conclusions Ethyl acetate is the optimal solvent for the extraction of compounds with antioxidant and anti-proliferative activities. The increased activities of catalase and superoxide dismutase in the treated cells could alter the antioxidant defense system, potentially contributing towards the anti-proliferative effect. There is great potential for the ethyl acetate extract of P. betle leaf as a source of natural antioxidants and to be developed as therapeutics in cancer treatment. PMID:23153283

2012-01-01

13

In vitro antifungal activity of hydroxychavicol isolated from Piper betle L  

PubMed Central

Background Hydroxychavicol, isolated from the chloroform extraction of the aqueous leaf extract of Piper betle L., (Piperaceae) was investigated for its antifungal activity against 124 strains of selected fungi. The leaves of this plant have been long in use tropical countries for the preparation of traditional herbal remedies. Methods The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of hydroxychavicol were determined by using broth microdilution method following CLSI guidelines. Time kill curve studies, post-antifungal effects and mutation prevention concentrations were determined against Candida species and Aspergillus species "respectively". Hydroxychavicol was also tested for its potential to inhibit and reduce the formation of Candida albicans biofilms. The membrane permeability was measured by the uptake of propidium iodide. Results Hydroxychavicol exhibited inhibitory effect on fungal species of clinical significance, with the MICs ranging from 15.62 to 500 ?g/ml for yeasts, 125 to 500 ?g/ml for Aspergillus species, and 7.81 to 62.5 ?g/ml for dermatophytes where as the MFCs were found to be similar or two fold greater than the MICs. There was concentration-dependent killing of Candida albicans and Candida glabrata up to 8 × MIC. Hydroxychavicol also exhibited an extended post antifungal effect of 6.25 to 8.70 h at 4 × MIC for Candida species and suppressed the emergence of mutants of the fungal species tested at 2 × to 8 × MIC concentration. Furthermore, it also inhibited the growth of biofilm generated by C. albicans and reduced the preformed biofilms. There was increased uptake of propidium iodide by C. albicans cells when exposed to hydroxychavicol thus indicating that the membrane disruption could be the probable mode of action of hydroxychavicol. Conclusions The antifungal activity exhibited by this compound warrants its use as an antifungal agent particularly for treating topical infections, as well as gargle mouthwash against oral Candida infections. PMID:20128889

2010-01-01

14

Growth inhibitory response and ultrastructural modification of oral-associated candidal reference strains (ATCC) by Piper betle L. extract  

PubMed Central

Candida species have been associated with the emergence of strains resistant to selected antifungal agents. Plant products have been used traditionally as alternative medicine to ease mucosal fungal infections. This study aimed to investigate the effects of Piper betle extract on the growth profile and the ultrastructure of commonly isolated oral candidal cells. The major component of P. betle was identified using liquid chromatography-mass spectrophotometry (LC-MS/MS). Seven ATCC control strains of Candida species were cultured in yeast peptone dextrose broth under four different growth environments: (i) in the absence of P. betle extract; and in the presence of P. betle extract at respective concentrations of (ii) 1 mg?mL?1; (iii) 3 mg?mL?1; and (iv) 6 mg?mL?1. The growth inhibitory responses of the candidal cells were determined based on changes in the specific growth rates (µ). Scanning electron microscopy (SEM) was used to observe any ultrastructural alterations in the candida colonies. LC-MS/MS was performed to validate the presence of bioactive compounds in the extract. Following treatment, it was observed that the µ-values of the treated cells were significantly different than those of the untreated cells (P<0.05), indicating the fungistatic properties of the P. betle extract. The candidal population was also reduced from an average of 13.44×106 to 1.78×106 viable cell counts (CFU)?mL?1. SEM examination exhibited physical damage and considerable morphological alterations of the treated cells. The compound profile from LC-MS/MS indicated the presence of hydroxybenzoic acid, chavibetol and hydroxychavicol in P. betle extract. The effects of P. betle on candida cells could potentiate its antifungal activity. PMID:24406634

Nordin, Mohd-Al-Faisal; Wan Harun, Wan Himratul-Aznita; Abdul Razak, Fathilah; Musa, Md Yusoff

2014-01-01

15

Growth inhibitory response and ultrastructural modification of oral-associated candidal reference strains (ATCC) by Piper betle L. extract.  

PubMed

Candida species have been associated with the emergence of strains resistant to selected antifungal agents. Plant products have been used traditionally as alternative medicine to ease mucosal fungal infections. This study aimed to investigate the effects of Piper betle extract on the growth profile and the ultrastructure of commonly isolated oral candidal cells. The major component of P. betle was identified using liquid chromatography-mass spectrophotometry (LC-MS/MS). Seven ATCC control strains of Candida species were cultured in yeast peptone dextrose broth under four different growth environments: (i) in the absence of P. betle extract; and in the presence of P. betle extract at respective concentrations of (ii) 1 mg?mL(-1); (iii) 3 mg?mL(-1); and (iv) 6 mg?mL(-1). The growth inhibitory responses of the candidal cells were determined based on changes in the specific growth rates (µ). Scanning electron microscopy (SEM) was used to observe any ultrastructural alterations in the candida colonies. LC-MS/MS was performed to validate the presence of bioactive compounds in the extract. Following treatment, it was observed that the µ-values of the treated cells were significantly different than those of the untreated cells (P<0.05), indicating the fungistatic properties of the P. betle extract. The candidal population was also reduced from an average of 13.44×10(6) to 1.78×10(6) viable cell counts (CFU)?mL(-1). SEM examination exhibited physical damage and considerable morphological alterations of the treated cells. The compound profile from LC-MS/MS indicated the presence of hydroxybenzoic acid, chavibetol and hydroxychavicol in P. betle extract. The effects of P. betle on candida cells could potentiate its antifungal activity. PMID:24406634

Nordin, Mohd-Al-Faisal; Wan Harun, Wan Himratul-Aznita; Abdul Razak, Fathilah; Musa, Md Yusoff

2014-03-01

16

Modulation of ionizing radiation induced oxidative imbalance by semi-fractionated extract of Piper betle  

PubMed Central

The study was planned to evaluate modulatory effect of aqueous extract of Piper betle leaf (PBL) on ionizing radiation mediated oxidative stress leading to normal tissues damage during radiotherapy and other radiation exposures. The total polyphenols and flavonoids known as free radical scavenger (chelators) were measured in the extract. To ascertain antioxidant potential of PBL extract, we studied free radical scavenging, metal chelation, reducing power, lipid peroxidation inhibition and ferric reducing antioxidant properties (FRAP ) using in vitro assays. Mice were exposed to varied radiation doses administered with the same extract prior to irradiation to confirm its oxidative stress minimizing efficacy by evaluating ferric reducing ability of plasma, reduced glutathione, lipid peroxidation and micro-nuclei frequency. PBL extract was effective in scavenging DPPH (up to 92% at 100 µg/ml) and superoxide radicals (up to 95% at 80 µg/ml), chelated metal ions (up to 83% at 50 µg/ml) and inhibited lipid peroxidation (up to 45.65% at 500 µg/ml) in a dose dependant manner using in vitro model. Oral administration of PBL extract (225 mg/kg body weight) 1 hr before irradiation in mice significantly enhanced (p < 0.01) radiation abated antioxidant potential of plasma and GSH level in all the observed organs. The treatment with extract effectively lowered the radiation induced lipid peroxidation at 24 hrs in all the selected organs with maximum inhibition in thymus (p < 0.01). After 48 hrs, lipid peroxidation was maximally inhibited in the group treated with the extract. Frequency of radiation induced micronucleated cells declined significantly (34.78%, p < 0.01) at 24 hrs post-irradiation interval by PBL extract administration. The results suggest that PBL extract has high antioxidant potential and relatively non-toxic and thus could be assertively used to mitigate radiotherapy inflicted normal tissues damage and also injuries caused by moderate doses of radiation during unplanned exposures. PMID:20716927

Verma, Savita; Dutta, Ajaswrata; Sankhwar, Sanghmitra; Shukla, Sandeep Kumar

2010-01-01

17

Protective effect of Piper betle leaf extract against cadmium-induced oxidative stress and hepatic dysfunction in rats  

PubMed Central

The present study was undertaken to examine the attenuative effect of Piper betle leaf extract (PBE) against cadmium (Cd) induced oxidative hepatic dysfunction in the liver of rats. Pre-oral supplementation of PBE (200 mg/kg BW) treated rats showed the protective efficacy against Cd induced hepatic oxidative stress. Oral administration of Cd (5 mg/kg BW) for four weeks to rats significantly (P > 0.05) elevated the level of serum hepatic markers such as serum aspartate transaminase (AST), serum alanine transaminase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), gamma-glutamyl transpeptidase (GGT), bilirubin (TBRNs), oxidative stress markers viz., thiobarbituric acid reactive substances (TBARS), lipid hydroperoxides (LOOH), protein carbonyls (PC) and conjugated dienes (CD) and significantly (P > 0.05) reduced the enzymatic antioxidants viz., superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST), glutathione reductase (GR) and glucose-6-phosphate dehydrogenase (G6PD) and non-enzymatic antioxidants Viz., reduced glutathione (GSH), total sulfhydryls (TSH), vitamin C and vitamin E in the liver. Pre-oral supplementation of PBE (200 mg/kg BW) in Cd intoxicated rats, the altered biochemical indices and pathological changes were recovered significantly (P > 0.05) which showed ameliorative effect of PBE against Cd induced hepatic oxidative stress. From the above findings, we suggested that the pre-administration of P. betle leaf extract exhibited remarkable protective effects against cadmium-induced oxidative hepatic injury in rats. PMID:23961183

Milton Prabu, S.; Muthumani, M.; Shagirtha, K.

2012-01-01

18

Comparative effect of Piper betle, Chlorella vulgaris and tocotrienol-rich fraction on antioxidant enzymes activity in cellular ageing of human diploid fibroblasts  

PubMed Central

Background Human diploid fibroblasts (HDFs) undergo a limited number of cellular divisions in culture and progressively reach a state of irreversible growth arrest, a process termed cellular ageing. Even though beneficial effects of Piper betle, Chlorella vulgaris and tocotrienol-rich fraction (TRF) have been reported, ongoing studies in relation to ageing is of interest to determine possible protective effects that may reverse the effect of ageing. The aim of this study was to evaluate the effect of P. betle, C. vulgaris and TRF in preventing cellular ageing of HDFs by determining the activity of antioxidant enzymes viz.; catalase, superoxide dismutase (SOD) and glutathione peroxidase. Methods Different passages of HDFs were treated with P. betle, C. vulgaris and TRF for 24 h prior to enzymes activity determination. Senescence-associated beta-galactosidase (SA ?-gal) expression was assayed to validate cellular ageing. Results In cellular ageing of HDFs, catalase and glutathione peroxidase activities were reduced, but SOD activity was heightened during pre-senescence. P. betle exhibited the strongest antioxidant activity by reducing SA ?-gal expression, catalase activities in all age groups, and SOD activity. TRF exhibited a strong antioxidant activity by reducing SA ?-gal expression, and SOD activity in senescent HDFs. C. vulgaris extract managed to reduce SOD activity in senescent HDFs. Conclusion P. betle, C. vulgaris, and TRF have the potential as anti-ageing entities which compensated the role of antioxidant enzymes in cellular ageing of HDFs. PMID:23948056

2013-01-01

19

An investigation of the vegetative anatomy of Piper sarmentosum, and a comparison with the anatomy of Piper betle (Piperaceae)  

Technology Transfer Automated Retrieval System (TEKTRAN)

Piper sarmentosum Roxb. (synonym, P. lolot C.DC.) is a southeast Asian medicinal plant valued for its medicinal and culinary uses. Hand-sections of the vegetative parts of P. sarmentosum were prepared and the anatomical features were studied by light microscopy and scanning electron microscopy. Th...

20

Effect of Piper betle and Brucea javanica on the Differential Expression of Hyphal Wall Protein (HWP1) in Non-Candida albicans Candida (NCAC) Species  

PubMed Central

The study aimed to identify the HWP1 gene in non-Candida albicans Candida species and the differential expression of HWP1 following treatment with Piper betle and Brucea javanica aqueous extracts. All candidal suspensions were standardized to 1 × 106?cells/mL. The suspension was incubated overnight at 37?°C (C. parapsilosis, 35°C). Candidal cells were treated with each respective extract at 1, 3, and 6?mg/mL for 24?h. The total RNA was extracted and reverse transcription-polymerase chain reaction was carried out with a specific primer of HWP1. HWP1 mRNAs were only detected in C. albicans, C. parapsilosis, and C. tropicalis. Exposing the cells to the aqueous extracts has affected the expression of HWP1 transcripts. C. albicans, C. parapsilosis, and C. tropicalis have demonstrated different intensity of mRNA. Compared to P. betle, B. javanica demonstrated a higher suppression on the transcript levels of HWP1 in all samples. HWP1 was not detected in C. albicans following the treatment of B. javanica at 1?mg/mL. In contrast, C. parapsilosis and C. tropicalis were shown to have HWP1 regulation. However, the expression levels were reduced upon the addition of higher concentration of B. javanica extract. P. betle and B. javanica have potential to be developed as oral health product. PMID:23853657

Jamil, Nur Alyaa; Jamaludin, Nor Hazwani; Nordin, Mohd-Al-Faisal

2013-01-01

21

BETL Documentation BETL Documentation  

E-print Network

of robust, extendable, and reliable numerical schemes being somehow related to the discretisation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2.2 Defining finite element spaces in BETL for the incorporation of other discretisation schemes such as, e.g., the still popular collocation methods. Over

Lang, Annika

22

Diversity of endophytic fungal community associated with Piper hispidum (Piperaceae) leaves.  

PubMed

Tropical and subtropical plants are rich in endophytic community diversity. Endophytes, mainly fungi and bacteria, inhabit the healthy plant tissues without causing any damage to the hosts. These fungi can be useful for biological control of pathogens and plant growth promotion. Some plants of the genus Piper are hosts of endophytic microorganisms; however, there is little information about endophytes on Piper hispidum, a medicinal shrub used as an insecticide, astringent, diuretic, stimulant, liver treatment, and for stopping hemorrhages. We isolated the fungal endophyte community associated with P. hispidum leaves from plants in a Brazilian forest remnant. The endophytic diversity was examined based on sequencing of the ITS1-5.8S-ITS2 region of rDNA. A high colonization frequency was obtained, as expected for tropical angiosperms. Isolated endophytes were divided into 66 morphogroups, demonstrating considerable diversity. We identified 21 isolates, belonging to 11 genera (Alternaria, Bipolaris, Colletotrichum, Glomerella, Guignardia, Lasiodiplodia, Marasmius, Phlebia, Phoma, Phomopsis, and Schizophyllum); one isolate was identified only to the order level (Diaporthales). Bipolaris was the most frequent genus among the identified endophytes. Phylogenetic analysis confirmed the molecular identification of some isolates to genus level while for others it was confirmed at the species level. PMID:22653631

Orlandelli, R C; Alberto, R N; Rubin Filho, C J; Pamphile, J A

2012-01-01

23

Evaluation of antibacterial and anthelmintic activities with total phenolic contents of Piper betel leaves  

PubMed Central

Objective: The study was conducted to investigate the antibacterial and anthelmintic activities and to determine total phenolic contents of methanolic extract of Piper betel leaves. Materials and Methods: The extract was subjected to assay for antibacterial activity using both gram positive and gram negative bacterial strains through disc diffusion method; anthelmintic activity with the determination of paralysis and death time using earthworm (Pheritima posthuma) at five different concentrations and the determination of total phenolic contents using the Folin-ciocalteau method. Results: The extract showed significant (p<0.01) zone of inhibitions against gram positive Staphylococcus aureus [(6.77±0.25) mm] and Gram negative Escherichia coli [(8.53±0.25) mm], Salmonella typhi [(5.20±0.26) mm], Shigella dysenteriae [(11.20±0.26) mm] compared to positive control Azithromycin (ranging from 20.10±0.17 to 25.20±0.35 mm) while no zone inhibitory activity was found for both the extract and the standard drug against Gram positive Bacillus cereus. The extract also showed potent anthelmintic activity requiring less time for paralysis and death compared to the standard drug albendazole (10 mg/ml). At concentrations 10, 20, 40, 60 and 80 mg/ml, leaves extract showed paralysis at mean time of 9.83±0.60, 8.50±0.29, 6.60±0.17, 6.20±0.44 and 4.16±0.60; death at 11.33±0.88, 9.67±0.33, 7.83±0.17, 7.16±0.60 and 5.16±0.72 minutes, respectively. Whereas the standard drug showed paralysis and death at 19.33±0.71 and 51.00±0.23 minutes respectively. The extract confirmed the higher concentration of phenolic contents (124.42±0.14 mg of GAE /g of extract) when screened for total phenolic compounds. Conclusion: As results confirmed potential antibacterial and anthelmintic activities of Piper betel leaves extract, therefore it may be processed for further drug research. PMID:25386394

Akter, Kazi Nahid; Karmakar, Palash; Das, Abhijit; Anonna, Shamima Nasrin; Shoma, Sharmin Akter; Sattar, Mohammad Mafruhi

2014-01-01

24

[Chemical composition of essential oils from leaves of Helicteres guazumifolia (Sterculiaceae), Piper tuberculatum (Piperaceae), Scoparia dulcis (Arecaceae) and Solanum subinerme (Solanaceae) from Sucre, Venezuela].  

PubMed

Essential oils, biosynthesized and accumulated in aromatic plants, have a wide range of applications in the pharmaceutical health, cosmetics, food and agricultural industry. This study aimed to analyze the secondary metabolites in some plant species in order to contribute to their chemotaxonomy. Leaves from Helicteres guazumifolia, Piper tuberculatum, Scoparia dulcis and Solanum subinerme were collected and their essential oils were obtained by means of hydro-distillation. The oil fraction was analyzed and identified by GC/MS. The extraction yields were of 0.004, 0.032, 0.016 and 0.005%, and the oil constituents of 88.00, 89.80, 87.50 and 89.47%, respectively. The principal oils found were: non-terpenoids volatile secondary metabolites (30.28%) in H. guazumifolia; sesquiterpenoids (20.82 and 26.09%) and oxigen derivated (52.19 and 25.18%) in P. tuberculatum and S. dulcis; and oxigen diterpenoids (39.67%) in S. subinerme. The diisobuthylphtalate (13.11%) in H. guazumifolia, (-)-spathulenol (11.37%) in P. tuberculatum and trans-phytol (8.29 and 36.00%) in S. dulcis and S. subinerme, were the principal constituents in their respective essential oils. The diisooctylphtalate were the essential oil common to all species, but the volatile compounds such as trans-pinane, L-linalool, beta-ionone, isophytol, neophytadiene, trans-phytol, dibutylphtalate and methyl hexadecanoate, were only detected in three of these essences. This suggests that these plants may require similar secondary metabolites for their ecological interactions, possibly due to common environmental factors. PMID:21721229

Ordaz, Gabriel; D'Armas, Haydelba; Yáñez, Dayanis; Moreno, Shailili

2011-06-01

25

77 FR 14316 - Airworthiness Directives; Piper Aircraft, Inc. (Type Certificate Previously Held by The New Piper...  

Federal Register 2010, 2011, 2012, 2013

...Directives; Piper Aircraft, Inc. (Type Certificate Previously Held by The New Piper Aircraft...certain Piper Aircraft, Inc. (type certificate previously held by The New Piper Aircraft...certain Piper Aircraft, Inc. (type certificate previously held by The New Piper...

2012-03-09

26

MUTAGENICITY OF NITRITE-TREATED AQUEOUS EXTRACT OF 'PIPER BETLE'; L  

EPA Science Inventory

Betel quid is chewed as a masticatory material by people in certain areas of Asia. The quid chewing has been related to oral cancer by epidemiological study. The mutagenic components in the aqueous extracts of betel quid ingredients were studied. Only nitrite-treated aqueous extr...

27

Gender-specific responses of Piper betle L. to low temperature stress: changes in chlorophyllase activity  

Microsoft Academic Search

Gender based differences in response to low temperature stress in leaf chlorophyll (Chl), and carotenoids (Car) contents and\\u000a chlorophyllase (Chlase) activity were monitored in male (Kapoori Vellaikodi and Madras Pan Kapoori) and female (Bangla Mahoba,\\u000a Desi Bangla and Kaker) betel vine landraces. Although female plants contained nearly two fold more Chl than male counterparts,\\u000a the low temperature induced Chl loss

N. Kumar; S. Gupta; A. N. Tripathi

2006-01-01

28

Leaving  

ERIC Educational Resources Information Center

Within this article, the author presents a personal story, "Leaving," which highlights the problematic experience of opposing established practice. The tale tells of the difficulty faced by creative agency when confronted by a constraining structural hegemony. Specifically, it draws attention to the professionalization of academic life through a…

Jones, Robyn L.

2011-01-01

29

Cenocladamide, a dihydropyridone alkaloid from Piper Craig D. Dodsona,  

E-print Network

Cenocladamide, a dihydropyridone alkaloid from Piper cenocladum Craig D. Dodsona, *, Lee A. Dyera alkaloid, cenocladamide, and a derivative of piplartine, 4'-desmethylpiplartine were isolated along cenocladum; Piperaceae; Leaves; Dihydropyridone alkaloids; N-(3',4',5'-trimethoxycinnamoyl)-D3 -pyridin-2-one

Dyer, Lee

30

Antioxidant and cytoprotective activities of Piper betle, Areca catechu, Uncaria gambir and betel quid with and without calcium hydroxide  

PubMed Central

Background Betel quid chewing is a popular habit in Southeast Asia. It is believed that chewing betel quid could reduce stress, strengthen teeth and maintain oral hygiene. The aim of this study was to investigate the antioxidant and cytoprotective activities of each of the ingredients of betel quid and compared with betel quid itself (with and without calcium hydroxide). The correlation of their cytoprotective and antioxidant activities with phenolic content was also determined. Methods Five samples (betel leaf, areca nut, gambir, betel quid and betel quid containing calcium hydroxide) were extracted in deionized distilled water for 12 hours at 37°C. Antioxidant activities were evaluated for radical scavenging activity using DPPH assay, ferric reducing activity using FRAP assay and lipid peroxidation inhibition activity using FTC assay. Total phenolic content (TPC) was determined using Folin-Ciocalteu procedure. Phenolic composition was analyzed using LC-MS/MS. Cytoprotective activity towards human gingival fibroblast cells was examined using MTT assay. Results Among the ingredients of betel quid, gambir demonstrated the highest antioxidant (DPPH - IC50?=?6.4?±?0.8 ?g/mL, FRAP - 5717.8?±?537.6 ?mol Fe(II)/mg), total phenolic content (TPC - 1142.5?±?106.8 ?g TAE/mg) and cytoprotective (100.1?±?4.6%) activities. Betel quid when compared with betel quid containing calcium hydroxide has higher antioxidant (DPPH - IC50 =59.4?±?4.4 ?g/mL, FRAP - 1022.2?±?235.7 ?mol Fe(II)/mg), total phenolic content (TPC - 140.0?±?22.3 ?g TAE/mg), and cytoprotective (113.5?±?15.9%) activities. However, all of the five samples showed good lipid peroxidation inhibition compared to vitamin E. LC-MS/MS analysis revealed the presence of quinic acid as the major compound of gambir and betel quid. A positive correlation was observed between TPC and radical scavenging (r?=?0.972), reducing power (r?=?0.981) and cytoprotective activity (r?=?0.682). Conclusions The betel quid has higher TPC, and antioxidant and cytoprotective activities than betel quid with calcium hydroxide. The quinic acid in betel quid may play an important role in the oral health protection. PMID:24330738

2013-01-01

31

Occurrence of piperidine alkaloids in Piper species collected in different areas.  

PubMed

A simple and convenient method was established for simultaneous quantitative determination of piperine and piperlonguminine in dried fruits of Piper longum and allied plants. The average content of piperine in P. longum (18.26 mg/g, range 12.05-33.23 mg/g) was about one half that of P. nigrum (40.09 mg/g, range 29.57-54.23 mg/g), but the content of piperlonguminine in P. longum was in the range of 0.42-1.82 mg/g, and the average content of piperlonguminne (0.91 mg/g) was about seven times higher than that in P. nigrum (0.13 mg/g). A sample of P. longum from Vietnam and a sample of P. retrofractum collected in Ishigaki, Japan, showed high contents of piperine and piperlonguminine. On the other hand, a sample of P. betle collected in Taiwan showed low content of piperine, and piperlonguminine was not detected. PMID:23625168

Bao, Narisu; Ochir, Sarangowa; Sun, Zhaorigetu; Borjihan, Gereltu; Yamagishi, Takashi

2014-01-01

32

Antimicrobial Activity of Terminalia catappa, Manilkara zapota and Piper betel Leaf Extract  

PubMed Central

Aqueous and methanol extract of the leaves of Terminalia catappa L., Manilkara zapota L. and Piper betel L. were evaluated for antibacterial activity against 10 Gram positive, 12 Gram negative bacteria and one fungal strain, Candida tropicalis. Piperacillin and gentamicin were used as standards for antibacterial assay, while fluconazole was used as standard for antifungal assay. The three plants showed different degree of activity against the microorganisms investigated. The methanolic extract was considerably more effective than aqueous extract in inhibiting the investigated microbial strains. The most active antimicrobial plant was Piper betel. PMID:20046756

Nair, R.; Chanda, Sumitra

2008-01-01

33

Antiherbivore prenylated benzoic acid derivatives from Piper kelleyi.  

PubMed

The known prenylated benzoic acid derivative 3-geranyl-4-hydroxy-5-(3?,3?-dimethylallyl)benzoic acid (1) and two new chromane natural products were isolated from the methanolic extract of the leaves of Piper kelleyi Tepe (Piperaceae), a midcanopy tropical shrub that grows in lower montane rain forests in Ecuador and Peru. Structure determination using 1D and 2D NMR analysis led to the structure of the chromene 2 and to the reassignment of the structure of cumanensic acid as 4, an isomeric chromene previously isolated from Piper gaudichaudianum. The structure and relative configuration of new chromane 3 was determined using 1D and 2D NMR spectroscopic analysis and was found to be racemic by ECD spectropolarimetry. The biological activity of 1-3 was evaluated against a lab colony of the generalist caterpillar Spodoptera exigua (Noctuidae), and low concentrations of 2 and 3 were found to significantly reduce fitness. Further consideration of the biosynthetic relationship of the three compounds led to the proposal that 1 is converted to 2 via an oxidative process, whereas 3 is produced through hetero-[4+2] dimerization of a quinone methide derived from the chromene 2. PMID:24422717

Jeffrey, Christopher S; Leonard, Michael D; Glassmire, Andrea E; Dodson, Craig D; Richards, Lora A; Kato, Massuo J; Dyer, Lee A

2014-01-24

34

Efficacy of Piper (Piperaceae) extracts for control of common home and garden insect pests.  

PubMed

Extracts from three species of the plant family Piperaceae, Piper nigrum [L.], Piper guineense [Schum & Thonn, and Piper tuberculatum [Jacq.], were tested for efficacy against insects from five orders. All three species contain isobutyl amides, plant secondary compounds that act as neurotoxins in insects. These materials are considered safe to mammals because Piper spp. were used for centuries for spice and medicinal purposes. When 24-h P. nigrum LC50 values were compared between common insect pests from eastern Canada and the northeastern United States, the most sensitive species in order of increasing lethal concentration were eastern tent caterpillar, Malacosoma americanum (F.) < European pine sawfly larvae, Neodiprion sertifer (Geoffroy) < spindle ermine moth larvae, Yponomeuta cagnagella [Hübner] < viburnum leaf beetle larvae, Pyrrhalta viburni [Paykull] < stripped cucumber beetle adults, Acalymma vittatum (F.) < Colorado potato beetle adults, Leptinotarsa decemlineata (Say) < Japanese beetle adults, Popillia japonica [Newman] < hairy chinch bug, Blissus leucopterus hirtis [Montandon]. The life stage tested was the point at which each species causes the greatest amount of damage to the host plant and the point at which most gardeners would likely choose to treat with a conventional synthetic insecticide. Greenhouse trials revealed that the pepper formulations also had a repellent activity, thus protecting plant leaves from 1) herbivory (lily leaf beetle, Lilioceris lilii [Scopoli], adults and larvae and stripped cucumber beetle adults) and 2) oviposition [European corn borer, Ostrinia nubilalis (Hübner)]. Combinations with other botanical extracts were additive at best in toxicity and repellent trials. Nontarget toxicity to beneficial invertebrates is a possibility because the P. nigrum LC50 for beneficial ladybird beetles was 0.2%. P. nigrum extracts can provide a reasonable level of control against lepidopteran and European pine sawfly larvae and also will work as a short-term repellent and feeding deterrent. It is recommended that the use of Piper extracts be restricted to small-scale spot treatments in residential areas where insect pest outbreaks have occurred. PMID:15384353

Scott, I M; Jensen, H; Nicol, R; Lesage, L; Bradbury, R; Sánchez-Vindas, P; Poveda, L; Arnason, J T; Philogène, B J R

2004-08-01

35

The Primordial Inflation Polarization Explorer (PIPER)  

NASA Astrophysics Data System (ADS)

The Primordial Inflation Polarization Explorer (Piper) is a balloon-borne cosmic microwave background (CMB) polarimeter designed to search for evidence of inflation by measuring the large-angular scale CMB polarization signal. Bicep2 recently reported a detection of B-mode power corresponding to the tensor-to-scalar ratio r = 0:2 on 2 degree scales. If the Bicep2 signal is caused by inflationary gravitational waves (IGWs), then there should be a corresponding increase in B-mode power on angular scales larger than 18 degrees. Piper is currently the only suborbital instrument capable of fully testing and extending the Bicep2 results by measuring the B-mode power spectrum on angular scales ? =~0:6° to 90°, covering both the reionization bump and recombination peak, with sensitivity to measure the tensor-to-scalar ratio down to r = 0:007, and four frequency bands to distinguish foregrounds. Piper will accomplish this by mapping 85% of the sky in four frequency bands (200, 270, 350, 600 GHz) over a series of 8 conventional balloon flights from the northern and southern hemispheres. The instrument has background-limited sensitivity provided by fully cryogenic (1.5 K) optics focusing the sky signal onto four 32x40-pixel arrays of time-domain multiplexed Transition-Edge Sensor (TES) bolometers held at 140 mK. Polarization sensitivity and systematic control are provided by front-end Variable- delay Polarization Modulators (VPMs), which rapidly modulate only the polarized sky signal at 3 Hz and allow Piper to instantaneously measure the full Stokes vector (I; Q;U; V ) for each pointing. We describe the Piper instrument and progress towards its first flight.

Lazear, Justin; Ade, Peter A. R.; Benford, Dominic; Bennett, Charles L.; Chuss, David T.; Dotson, Jessie L.; Eimer, Joseph R.; Fixsen, Dale J.; Halpern, Mark; Hilton, Gene; Hinderks, James; Hinshaw, Gary F.; Irwin, Kent; Jhabvala, Christine; Johnson, Bradley; Kogut, Alan; Lowe, Luke; McMahon, Jeff J.; Miller, Timothy M.; Mirel, Paul; Moseley, S. Harvey; Rodriguez, Samelys; Sharp, Elmer; Staguhn, Johannes G.; Switzer, Eric R.; Tucker, Carole E.; Weston, Amy; Wollack, Edward J.

2014-07-01

36

The Primordial Inflation Polarization Explorer (PIPER)  

NASA Technical Reports Server (NTRS)

The Primordial Inflation Polarization ExploreR (Piper) is a balloon-borne cosmic microwave background (CMB) polarimeter designed to search for evidence of inflation by measuring the large-angular scale CMB polarization signal. Bicep2 recently reported a detection of B-mode power corresponding to the tensor-to-scalar ratio r = 0.2 on approximately 2 degree scales. If the Bicep2 signal is caused by inflationary gravitational waves (IGWs), then there should be a corresponding increase in B-mode power on angular scales larger than 18 degrees. Piper is currently the only suborbital instrument capable of fully testing and extending the Bicep2 results by measuring the B-mode power spectrum on angular scales theta ? = approximately 0.6 deg to 90 deg, covering both the reionization bump and recombination peak, with sensitivity to measure the tensor-to-scalar ratio down to r = 0.007, and four frequency bands to distinguish foregrounds. Piper will accomplish this by mapping 85% of the sky in four frequency bands (200, 270, 350, 600 GHz) over a series of 8 conventional balloon flights from the northern and southern hemispheres. The instrument has background-limited sensitivity provided by fully cryogenic (1.5 K) optics focusing the sky signal onto four 32×40-pixel arrays of time-domain multiplexed Transition-Edge Sensor (TES) bolometers held at 140 milli-Kelvin. Polarization sensitivity and systematic control are provided by front-end Variabledelay Polarization Modulators (VPMs), which rapidly modulate only the polarized sky signal at 3 Hz and allow Piper to instantaneously measure the full Stokes vector (I,Q,U,0V) for each pointing. We describe the Piper instrument and progress towards its first flight.

Lazear, Justin Scott; Ade, Peter A.; Benford, Dominic J.; Bennett, Charles L.; Chuss, David T.; Dotson, Jessie L.; Eimer, Joseph R.; Fixsen, Dale J.; Halpern, Mark; Hinderks, James; Hinshaw, Gary F.; Irwin, Kent; Jhabvala, Christine; Johnson, Bradley; Kogut, Alan; Lowe, Luke; McMahon, Jeff J.; Miller, Timothy M.; Mirel, Paul; Moseley, S. Harvey; Rodriguez, Samelys; Staguhn, Johannes G.; Switzer, Eric R.; Tucker, Carole E.; Weston, Amy; Wollack, Edward

2014-01-01

37

Piper's daisy Status: State Sensitive  

E-print Network

General Description: Slender perennial with a taproot and short branched caudex; stem 1 to 4 inches high, seldom much exceeding the leaves, hirsute with mostly appressed or ascending hairs; leaves numerous, not all basal, linear or nearly so, lax and usually curved, up to 1b inch long and 1/16 inch wide, hispid-ciliate on the margins, especially below, and appressedhairy on the surface, the lower with conspicuously enlarged, whitish-hardened base; heads solitary or few, small, the disk to d inch wide; involucre c to inch high, spreading-hirsute with long white hairs; rays 25-40, yellow, c to d inch long, 1/16 inch wide; disk corollas mostly c to d inch long; pappus of 15-25 bristles and often some short outer setae. Identification Tips: The taxon is most easily confused with Erigeron linearis. The margins of the lower leaves of E. piperianus have spreading hairs as opposed to appressed hairs in E. linearis. The taxon is also closely related to E. chrysopsidis. Erigeron piperianus is distinguished by the pubescence on the stem which is appressed or ascending rather than spreading, the smaller involucres, and narrower, laxer leaves. Also, E. piperianus is a smaller and more delicate plant which apparently does not overlap the distribution of E. chrysopsidis.

Rank Gs

38

Anticancer Principles from Medicinal Piper (?? Hú Ji?o) Plants  

PubMed Central

The ethnomedical uses of Piper (?? Hú Ji?o) plants as anticancer agents, in vitro cytotoxic activity of both extracts and compounds from Piper plants, and in vivo antitumor activity and mechanism of action of selected compounds are reviewed in the present paper. The genus Piper (Piperaceae) contains approximately 2000 species, of which 10 species have been used in traditional medicines to treat cancer or cancer-like symptoms. Studies have shown that 35 extracts from 24 Piper species and 32 compounds from Piper plants possess cytotoxic activity. Amide alkaloids account for 53% of the major active principles. Among them, piplartine (piperlongumine) shows the most promise, being toxic to dozens of cancer cell lines and having excellent in vivo activity. It is worthwhile to conduct further anticancer studies both in vitro and in vivo on Piper plants and their active principles. PMID:24872928

Wang, Yue-Hu; Morris-Natschke, Susan L.; Yang, Jun; Niu, Hong-Mei; Long, Chun-Lin; Lee, Kuo-Hsiung

2014-01-01

39

The effect of Piper betle and Psidium guajava extracts on the cell-surface hydrophobicity of selected early settlers of dental plaque  

Microsoft Academic Search

The adhesion of early settlers of dental plaque to the tooth surface has a role in the initiation of the development of dental plaque. The hydrophobic surface properties of the bacteria cell wall are indirectly responsible for the adhesion of the bacteria cell to the acquired pellicle on the tooth surfaces. In this study, the effect of aqueous extract of

Fathilah Abdul Razak; Rofina Yasmin Othman; Zubaidah Haji Abd Rahim

2006-01-01

40

The Primordial Inflation Polarization Explorer (PIPER)  

E-print Network

The Primordial Inflation Polarization Explorer (PIPER) is a balloon-borne cosmic microwave background (CMB) polarimeter designed to search for evidence of inflation by measuring the large-angular scale CMB polarization signal. BICEP2 recently reported a detection of B-mode power corresponding to the tensor-to-scalar ratio r = 0.2 on ~2 degree scales. If the BICEP2 signal is caused by inflationary gravitational waves (IGWs), then there should be a corresponding increase in B-mode power on angular scales larger than 18 degrees. PIPER is currently the only suborbital instrument capable of fully testing and extending the BICEP2 results by measuring the B-mode power spectrum on angular scales $\\theta$ = ~0.6 deg to 90 deg, covering both the reionization bump and recombination peak, with sensitivity to measure the tensor-to-scalar ratio down to r = 0.007, and four frequency bands to distinguish foregrounds. PIPER will accomplish this by mapping 85% of the sky in four frequency bands (200, 270, 350, 600 GHz) over a ...

Lazear, Justin; Benford, Dominic; Bennett, Charles L; Chuss, David T; Dotson, Jessie L; Eimer, Joseph R; Fixsen, Dale J; Halpern, Mark; Hilton, Gene; Hinderks, James; Hinshaw, Gary F; Irwin, Kent; Jhabvala, Christine; Johnson, Bradley; Kogut, Alan; Lowe, Luke; McMahon, Jeff J; Miller, Timothy M; Mirel, Paul; Moseley, S Harvey; Rodriguez, Samelys; Sharp, Elmer; Staguhn, Johannes G; Switzer, Eric R; Tucker, Carole E; Weston, Amy; Wollack, Edward J

2014-01-01

41

The Primordial Inflation Polarization Explorer (PIPER)  

NASA Technical Reports Server (NTRS)

The Primordial Inflation Polarization Explorer (PIPER) is it balloon-borne instrument designed to search for the faint signature of inflation in the polarized component of the cosmic microwave background (C-N-113). Each flight will be configured for a single frequency, but in order to aid in the removal of the polarized foreground signal due to Galactic dust, the filters will be changed between flights. In this way, the CMB polarization at a total of four different frequencies (200, 270, 350, and 600 GHz) will be, measured on large angular scales. PIPER consists of a pair of cryogenic telescopes, one for measuring each of Stokes Q and U in the instrument frame. Each telescope receives both linear orthogonal polarizations in two 32 x 40 element planar arrays that utilize Transition-Edge Sensors (TES). The first element in each telescope is a variable-delay polarization modulator (VPM) that fully modulates the linear Stokes parameter to which the telescope is sensitive. There are several advantages to this architecture. First, by modulating at the front of the optics, instrumental polarization is unmodulated and is therefore cleanly separated from source polarization. Second, by implementing this system with the appropriate symmetry, systematic effects can be further mitigated. In the PIPER design, many of the. systematics are manifest in the unmeasured linear Stokes parameter for each telescope and this can be separated from the desired signal. Finally, the modulation cycle never mixes the Q and U linear Stokes parameters, and thus residuals in the modulation do not twist the observed polarization vector. This is advantageous because measuring the angle of linear polarization is critical for separating the inflationary signal from other polarized components.

Chuss, David T.; Ade, Peter A. R.; Benford, Dominic J.; Bennett, Charles L.; Dotson, Jessie L.; Eimer, Joseph R.; Fixsen, Dale J.; Halpern, Mark; Hilton, Gene; Hinderks, James; Hinshaw, Gary; Irwin, Kent; Jackson, Michael L.; Jah, Muzariatu A.; Jethava, Nikhil; Jhabvala, Christine; Kogut, Alan J.; Lowe, Luke; McCullagh, Nuala; Miller, Timothy; Mirel, Paul; Moseley, S. Harvey; Rodriguez, Samelys; Rostem, Karwan; Sharp, Elmer

2010-01-01

42

Piper nigrum and piperine: an update.  

PubMed

Black pepper (Piper nigrum L.) is a very widely used spice, known for its pungent constituent piperine. However, in addition to its culinary uses, pepper has important medicinal and preservative properties, and, more recently, piperine has been shown to have fundamental effects on p-glycoprotein and many enzyme systems, leading to biotransformative effects including chemoprevention, detoxification, and enhancement of the absorption and bioavailability of herbal and conventional drugs. Based on modern cell, animal, and human studies, piperine has been found to have immunomodulatory, anti-oxidant, anti-asthmatic, anti-carcinogenic, anti-inflammatory, anti-ulcer, and anti-amoebic properties. In this review, the chemical constituents, biological activities, effects of processing, and future potential of black pepper and piperine have been discussed thoroughly. PMID:23625885

Meghwal, Murlidhar; Goswami, T K

2013-08-01

43

Bioactivities of Piper aduncum L. and Piper obliquum Ruiz & Pavon (Piperaceae) essential oils from Eastern Ecuador.  

PubMed

Essential oils from aerial parts of Piper aduncum (Matico) and Piper obliquum (Anis del Oriente) of ecuadorian origin were analyzed by GC-FID, GC-MS, (13)C NMR and their biological and pharmacological activities were assessed. Chemical composition proved to be unusually different from previous reports for safrole-rich P. obliquum (45.8%), while P. aduncum main constituent was dillapiol (45.9%). No genotoxic activity was found in the Ames/Salmonella typhimurium (TA98 and TA100) assay, either with or without S9 activation. Mutagen-protective properties, evaluated using sodium azide, 2-nitrofluorene and 2-aminoanthracene as mutagens/promutagens, was observed against promutagen 2-aminoanthracene, likely in consequence of microsomial deactivation. Antimicrobial assays have been performed on Gram+/Gram- bacteria, dermatophyte and phytopathogenic fungi and best results were provided by P. aduncum against fungal strains with complete inhibition at 500?g/ml. Preliminary analgesic and antithrombotic activities evidenced the absence of the former in hot plate and edema assays and a limited antiplatelet action against three different agonists (ADP, AA and U46619). Both oils have a very limited antioxidant capacity. PMID:21783920

Guerrini, Alessandra; Sacchetti, Gianni; Rossi, Damiano; Paganetto, Guglielmo; Muzzoli, Mariavittoria; Andreotti, Elisa; Tognolini, Massimiliano; Maldonado, Maria E; Bruni, Renato

2009-01-01

44

BEARDSLEY AND PIPER ROTOMOLD CORMATIC ROTATING TO POSITION THE EMPTY ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

BEARDSLEY AND PIPER ROTOMOLD CORMATIC ROTATING TO POSITION THE EMPTY CORE BOX UNDER A FULL MAGAZINE AND THE FULL CORE BOX TO AN OPEN POSITION TO ALLOW CORE REMOVAL. WILLIAM SEAL STACK CORES IN FOREGROUND. - Southern Ductile Casting Company, Core Making, 2217 Carolina Avenue, Bessemer, Jefferson County, AL

45

Antioxidant activity of combined ethanolic extract of Eclipta alba and Piper longum Linn.  

PubMed

The in-vitro free radical scavenging efficacy of the combined ethanolic Biherbal extract (BHE) from equal quantities of the leaves of Eclipta alba and seeds of Piper longum was investigated. This was compared with its individual preparation of ethanolic extract of Eclipta alba (EAE) and ethanolic extract of Piper longum (PLE). The 1, 1, diphenyl -2-picrylhydrazyl (DPPH), super oxide, nitric oxide, hydroxyl radical scavenging activity and reducing power from BHE, EAE, and PLE were investigated employing various established in vitro systems. Total phenolic and flavonoid content were also determined. The results revealed that BHE has notable activity in quenching of DPPH, super oxide, nitric oxide, and hydroxyl radicals when compared to its individual preparation of EAE and PLE. The BHE at 1000?g/ml showed maximum scavenging of DPPH (88.75%) super oxide (84.78%) nitric oxide (89.02%) and hydroxyl (82.82%) against the scavenging of EAE and PLE which showed DPPH (81.77%,83.54%) super oxide (79.88 ± 1.84, 80.88 ± 1.44%) nitric-oxide (76.14 ± 1.80, 77.2 ± 1.18%) and hydroxyl (79.86%, 74.64%) radicals respectively at the same concentration. A linear correlation between BHE and reducing power was also observed. The quantitative estimation of the extract revealed the considerable amount of phenols and flavonoids. The results of this study strongly indicate that the BHE has more potent antioxidant potential action than its individual preparation EAE or PLE. PMID:22718673

Ramesh, Vasuki; Hari, Rajeswary; Pandian, Samudram; Arumugam, Geetha

2011-01-01

46

A background color scheme for piper plots to spatially visualize hydrochemical patterns.  

PubMed

The combination of ternary diagrams of cations and anions with a central diamond graph make the Piper plot very useful in visualizing groundwater chemistry datasets. One of the major drawbacks is that it is hard to link spatial attributes of the dataset to the plot. In this study, we propose a background color scheme of the Piper plot so that spatial representations of these data can be colored according to their location in the Piper plot. The color scheme is chosen to have maximum resolution while still being perceptually uniform. The linking between Piper plot and maps through this color scheme allows the interpretation of the trends and processes deduced from the Piper plot in terms of the location in the aquifer, the geology, and the groundwater flow dynamics. The colored Piper plot is applied to a groundwater quality dataset of the Condamine Alluvium in Queensland, Australia. PMID:24102292

Peeters, Luk

2014-01-01

47

PIPER: An FFT-Based Protein Docking Program with Pairwise Potentials  

E-print Network

PIPER: An FFT-Based Protein Docking Program with Pairwise Potentials Dima Kozakov,1 Ryan Brenke,2 by an earlier FFT method. The docking program PIPER is freely available for noncommercial applications. Proteins Transform (FFT) correlation approach to protein­protein docking can evaluate the energies of billions

Vajda, Sandor

48

proteinsSTRUCTURE O FUNCTION O BIOINFORMATICS Docking with PIPER and refinement  

E-print Network

proteinsSTRUCTURE O FUNCTION O BIOINFORMATICS Docking with PIPER and refinement with SDU in rounds ABSTRACT Our approach to protein­protein docking includes three main steps. First we run PIPER, a new rigid using a multistep approach to protein­protein docking.1­6 The first step is exploring the conforma

Vajda, Sandor

49

Plants feed ants: food bodies of myrmecophytic Piper and their significance for the interaction with Pheidole bicornis ants  

Microsoft Academic Search

Several species of Piper (Piperaceae) live in symbiosis with Pheidole bicornis (Formicidae-Myrmicinae) on the southern Pacific slope of Costa Rica. These plants produce small single-celled food bodies (FBs) in leaf domatia, formed by the petiole bases and roofing leaf sheaths. In the present study the dependency of ants on FBs of Piper fimbriulatum as a food source was analysed by

Renate C. Fischer; Andreas Richter; Wolfgang Wanek; Veronika Mayer

2002-01-01

50

Anticholinesterase and Antityrosinase Activities of Ten Piper Species from Malaysia  

PubMed Central

Purpose: The aim of this study was to investigate acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and antityrosinase activities of extracts from ten Piper species namely; P. caninum, P. lanatum, P. abbreviatum, P. aborescens, P. porphyrophyllum, P. erecticaule, P. ribesioides, P. miniatum, P. stylosum, and P. majusculum. Methods: Anticholinesterase and antityrosinase activities were evaluated against in vitro Ellman spectroscopy method and mushroom tyrosinase, respectively. Results: The EtOAc extract of P. erecticaule showed the highest AChE and BChE inhibitory with 22.9% and 70.9% inhibition, respectively. In antityrosinase activity, all extracts of P. porphyrophyllum showed the highest inhibitory effects against mushroom tyrosinase, compared to standard, kojic acid. Conclusion: This study showed that P. erecticaule and P. porphyrophyllum have potential AChE/BChE and tyrosinase inhibition activities. The respective extracts can be explored further for the development of novel lead as AChE/BChE and tyrosinase inhibitors in therapeutic management of Alzheimer’s disease.

Salleh, Wan Mohd Nuzul Hakimi Wan; Hashim, Nur Athirah; Ahmad, Farediah; Heng Yen, Khong

2014-01-01

51

CSU Leave Program Types of Leave Programs  

E-print Network

Policy · California Pregnancy Disability Leave · Education Code 89519 Leave · Maternity/Paternity/Adoption/parental or roommates) ­ Bereavement in the case of death of a person in the immediate family (when bereavement leave as spouse, parent, child, or domestic partner · Medical, dental, and vision benefits continue while on FML

de Lijser, Peter

52

The developmental basis of an evolutionary diversification of female gametophyte structure in Piper and Piperaceae  

PubMed Central

Background and Aims Fritillaria-type female gametophyte development is a complex, yet homoplasious developmental pattern that is interesting from both evolutionary and developmental perspectives. Piper (Piperaceae) was chosen for this study of Fritillaria-type female gametophyte development because Piperales represent a ‘hotspot’ of female gametophyte developmental evolution and have been the subject of several recent molecular phylogenetic analyses. This wealth of phylogenetic and descriptive data make Piper an excellent candidate for inferring the evolutionary developmental basis for the origin of Fritillaria-type female gametophytes. Methods Developing ovules of Piper peltatum were taken from greenhouse collections, embedded in glycol methacrylate, and serially sectioned. Light microscopy and laser scanning confocal microscopy were combined to produce three-dimensional computer reconstructions of developing female gametophytes. The ploidies of the developing embryos and endosperms were calculated using microspectrofluorometry. Key Results The data describe female gametophyte development in Piper with highly detailed three-dimensional models, and document two previously unknown arrangements of megaspore nuclei during early development. Also collected were microspectrofluorometric data that indicate that Fritillaria-type female gametophyte development in Piper results in pentaploid endosperm. Conclusions The three-dimensional models resolve previous ambiguities in developmental interpretations of Fritillaria-type female gametophytes in Piper. The newly discovered arrangements of megaspore nuclei that are described allow for the construction of explicit hypotheses of female gametophyte developmental evolution within Piperaceae, and more broadly throughout Piperales. These detailed hypotheses indicate that the common ancestor of Piperaceae minus Verhuellia had a Drusa-type female gametophyte, and that evolutionary transitions to derived tetrasporic female gametophyte ontogenies in Piperaceae, including Fritillaria-type female gametophyte development, are the consequence of key nuclear migration and patterning events at the end of megasporogenesis. PMID:19202137

Madrid, Eric N.; Friedman, William E.

2009-01-01

53

[Oil of Piper longum unsaponifiable matter prevents cholesterol gallstone formation].  

PubMed

To observe the effect of various doses of oil of Piper longum unsaponifiable matter (OPUM) to cholesterol gallstones in experimental mice. C57BL/6 mice (n = 60) were randomly divided into 6 groups: control group, model group, OPUM (15, 30 and 60 mg x kg(-1)) group and ursodeoxycholic acid (UDCA, 60 mg x kg(-1)) group, administered for 10 weeks. The level of serum lipid and liver function enzymes were tested. The gallbladder was removed and bile was obtained by centrifugation. Next, the levels of the bile total cholesterol (TC), phospholipid (PL) and bile acid (TBA) were measured. The indicators of lipid peroxidation were determined and cholesterol saturation index (CSI) was calculated. The liver histological changes were observed by HE staining. The results showed that serum TC, TG (triglycerides) and AST (aspartate transaminase) contents, gallbladder cholesterol crystallization and CSI increased significantly (P < 0.05). In addition, the activity of SOD decreased significantly and MDA content increased significantly in liver (P < 0.05). HE staining results showed that the hepatic cord disorder and intracellular lipid droplets increased significantly. All results indicate that lithogenic diet lead to the formation of cholesterol gallstones. In OPUM (30 and 60 mg x kg(-1)) group, serum TC, TG and AST content, gallbladder cholesterol crystallization and CSI decreased significantly, the activity of SOD increased significantly and MDA content decreased significantly. HE staining results showed that OPUM can improve the morphology of liver cell, reduce the degree of hepatic cord disorders and restore the cell morphology close to normal. The cause of OPUM prevents cholesterol gallstone formation maybe due to protect the integrity of the liver cells, lower CSI, and reduce cholesterol crystal formation and hence prevent cholesterol gallstone formation. PMID:24133988

Xu, Shuang; Hu, Jin-Feng; Chu, Shi-Feng; Han, Ning; Li, Jing-Wei; Li, Yue-Ting; Chen, Nai-Hong

2013-07-01

54

Piper and Vismia Species from Colombian Amazonia Differentially Affect Cell Proliferation of Hepatocarcinoma Cells  

PubMed Central

There is an increasing interest to identify plant-derived natural products with antitumor activities. In this work, we have studied the effects of aqueous leaf extracts from Amazonian Vismia and Piper species on human hepatocarcinoma cell toxicity. Results showed that, depending on the cell type, the plants displayed differential effects; thus, Vismia baccifera induced the selective killing of HepG2, while increasing cell growth of PLC-PRF and SK-HEP-1. In contrast, these two last cell lines were sensitive to the toxicity by Piper krukoffii and Piper putumayoense, while the Piperaceae did not affect HepG2 growth. All the extracts induced cytotoxicity to rat hepatoma McA-RH7777, but were innocuous (V. baccifera at concentrations < 75 µg/mL) or even protected cells from basal death (P. putumayoense) in primary cultures of rat hepatocytes. In every case, cytotoxicity was accompanied by an intracellular accumulation of reactive oxygen species (ROS). These results provide evidence for the anticancer activities of the studied plants on specific cell lines and suggest that cell killing could be mediated by ROS, thus involving mechanisms independent of the plants free radical scavenging activities. Results also support the use of these extracts of the Vismia and Piper genera with opposite effects as a model system to study the mechanisms of the antitumoral activity against different types of hepatocarcinoma. PMID:25558904

Lizcano, Leandro J.; Siles, Maite; Trepiana, Jenifer; Hernández, M. Luisa; Navarro, Rosaura; Ruiz-Larrea, M. Begoña; Ruiz-Sanz, José Ignacio

2014-01-01

55

Synergistic effects of amides from two piper species on generalist and specialist herbivores.  

PubMed

Plants use a diverse mix of defenses against herbivores, including multiple secondary metabolites, which often affect herbivores synergistically. Chemical defenses also can affect natural enemies of herbivores via limiting herbivore populations or by affecting herbivore resistance to parasitoids. In this study, we performed feeding experiments to examine the synergistic effects of imides and amides (hereafter "amides") from Piper cenocladum and P. imperiale on specialist (Eois nympha, Geometridae) and generalist (Spodoptera frugiperda, Noctuidae) lepidopteran larvae. Each Piper species has three unique amides, and in each experiment, larvae were fed diets containing different concentrations of single amides or combinations of the three. The amides from P. imperiale had negative synergistic effects on generalist survival and specialist pupal mass, but had no effect on specialist survival. Piper cenocladum amides also acted synergistically to increase mortality caused by parasitoids, and the direct negative effects of mixtures on parasitoid resistance and pupal mass were stronger than indirect effects via changes in growth rate and approximate digestibility. Our results are consistent with plant defense theory that predicts different effects of plant chemistry on generalist versus adapted specialist herbivores. The toxicity of Piper amide mixtures to generalist herbivores are standard bottom-up effects, while specialists experienced the top-down mediated effect of mixtures causing reduced parasitoid resistance and associated decreases in pupal mass. PMID:20809141

Richards, Lora A; Dyer, Lee A; Smilanich, Angela M; Dodson, Craig D

2010-10-01

56

High-frequency plant regeneration through cyclic secondary somatic embryogenesis in black pepper ( Piper nigrum L.)  

Microsoft Academic Search

A high-frequency plantlet regeneration protocol was developed for black pepper (Piper nigrum L.) through cyclic secondary somatic embryogenesis. Secondary embryos formed from the radicular end of the primary somatic embryos which were originally derived from micropylar tissues of germinating seeds on growth regulator-free SH medium in the absence of light. The process of secondary embryogenesis continued in a cyclic manner

R. Ramakrishnan Nair; S. Dutta Gupta

2006-01-01

57

Chemical composition and antimicrobial activity of essential oil of Piper angustifolium.  

PubMed

The essential oil for Piper angustifolium Lam. was analyzed by gas chromatography-mass spectrometry (GC/MS) technique. Camphor and camphene were the main constituents. This oil exhibited bacteriostatic and fungistatic activities against Trichophyton mentagrophytes, Pseudomonas aeruginosa, Candida albicans, Cryptococcus neoformans, Aspergillus flavus, Aspergillus fumigatus, and Escherichia coli. PMID:8792674

Tirillini, B; Velasquez, E R; Pellegrino, R

1996-08-01

58

Piper and vismia species from colombian amazonia differentially affect cell proliferation of hepatocarcinoma cells.  

PubMed

There is an increasing interest to identify plant-derived natural products with antitumor activities. In this work, we have studied the effects of aqueous leaf extracts from Amazonian Vismia and Piper species on human hepatocarcinoma cell toxicity. Results showed that, depending on the cell type, the plants displayed differential effects; thus, Vismia baccifera induced the selective killing of HepG2, while increasing cell growth of PLC-PRF and SK-HEP-1. In contrast, these two last cell lines were sensitive to the toxicity by Piper krukoffii and Piper putumayoense, while the Piperaceae did not affect HepG2 growth. All the extracts induced cytotoxicity to rat hepatoma McA-RH7777, but were innocuous (V. baccifera at concentrations < 75 µg/mL) or even protected cells from basal death (P. putumayoense) in primary cultures of rat hepatocytes. In every case, cytotoxicity was accompanied by an intracellular accumulation of reactive oxygen species (ROS). These results provide evidence for the anticancer activities of the studied plants on specific cell lines and suggest that cell killing could be mediated by ROS, thus involving mechanisms independent of the plants free radical scavenging activities. Results also support the use of these extracts of the Vismia and Piper genera with opposite effects as a model system to study the mechanisms of the antitumoral activity against different types of hepatocarcinoma. PMID:25558904

Lizcano, Leandro J; Siles, Maite; Trepiana, Jenifer; Hernández, M Luisa; Navarro, Rosaura; Ruiz-Larrea, M Begoña; Ruiz-Sanz, José Ignacio

2014-01-01

59

A COMPARISON OF FRUIT REMOVAL BY BATS AND BIRDS FROM PIPER HISfIDUM SW.  

E-print Network

... ; A COMPARISON OF FRUIT REMOVAL BY BATS AND BIRDS FROM PIPER HISfIDUM SW. (PIPERACEAE. Central AlOOrica (Received: January 5, 1989) ABSTRAC,r I measured fruit removal by bats and birds from in recently distubed second growth habitat during a period of heavy P. hispidum fruiting; plants are e

O'Donnell, Sean

60

BEARDSLEY AND PIPER (B&P) CORE BLOWING MACHINE. VIRGINIA BLAKELY MANUALLY ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

BEARDSLEY AND PIPER (B&P) CORE BLOWING MACHINE. VIRGINIA BLAKELY MANUALLY FILLING SAND MAGAZINE THAT WILL ROTATE WITH THE CORE BOX, FILLING IT UNDER PRESSURE SIMILAR TO THE CORE MACHINE IN THE BACKGROUND. - Southern Ductile Casting Company, Core Making, 2217 Carolina Avenue, Bessemer, Jefferson County, AL

61

Improved Exposure Characterization with Robotic (PIPER) Sampling and Association with Children's Respiratory Symptoms, Asthma and Eczema  

PubMed Central

Background/objectives Particulate matter (PM) and its constituents are recognized risk factors for the development of respiratory symptoms and illness in children. Most measurements of exposure have relied upon stationary indoor monitors (SIMs), overlooking the role of resuspended PM. To improve exposure characterization to resuspended aerosol particulate matter a recently developed methodology has been employed. The goal of this study is to characterize the resuspendable fraction of house dust and early childhood exposures to PM and its constituents in the child's home and compare conventional SIM and the Pre-toddler Inhalable Particulate Environmental Robotic (PIPER), an innovative mobile sampler. The study seeks to demonstrate that PIPER provides a more relevant estimate of exposure from inhalable particulate through improved correlation with respiratory symptoms in young children. Methods Seventy-five households with children between 3-59 months of age were recruited from clinics in central New Jersey. Demographic information and a health questionnaire based upon that used by the International Study of Allergies and Asthma in Childhood (ISAAC) and household data were collected. Household exposures to inhalable PM (PM100) and endotoxin were determined with simultaneous SIM and mobile (PIPER) sampling. Results Univariate and multivariate analyses were carried out. History of wheeze [’recent’ (<1 year) and ’ever’], cough, asthma, and eczema were evaluated. Multivariate analysis models included PM100 and endotoxin levels by tertiles of exposure. Risk of asthma for the highest tertile of PM100, as measured by PIPER (Odds Ratio = 4.2; 95% Confidence Interval 0.7 – 24.0) was compared to measurements by SIM (Odds Ratio = 0.7; 95% Confidence Interval 0.2 – 2.6). Conclusions Measurement of PM and its constituents with PIPER are more strongly associated with asthma, eczema and wheeze than measurements using SIMs. Application of this methodology may provide useful insights into early childhood exposures related to the etiology of childhood illnesses associated with inhalation exposures. PMID:24802555

Ramagopal, Maya; Wang, Zuocheng; Black, Kathleen; Hernandez, Marta; Stambler, Adam A; Emoekpere, Osiloke H.; Mainelis, Gediminas; Shalat, Stuart L.

2015-01-01

62

Stanford Community Leave Bank A voluntary leave time donation program  

E-print Network

Stanford Community Leave Bank A voluntary leave time donation program July 1, 2012 h t t p : / / h of accrued vacation to the Stanford Community Leave Bank (SCLB) central leave bank. In accordance with tax vacation leave hours from their unused balance to a central leave bank fund. This central leave bank fund

Straight, Aaron

63

5 CFR 630.1117 - Procedures for returning unused donated annual leave to emergency leave donors and leave banks.  

Code of Federal Regulations, 2010 CFR

...returning unused donated annual leave to emergency leave donors and leave banks. 630...SERVICE REGULATIONS ABSENCE AND LEAVE Emergency Leave Transfer Program § 630.1117...returning unused donated annual leave to emergency leave donors and leave banks....

2010-01-01

64

Describing Oak Leaves  

NSDL National Science Digital Library

Learners work in teams to investigate how scientists use physical characteristics to classify living things. First, learners examine drawings of a variety of leaves from different species of oak trees and work to develop the characteristics of a "typical" oak leaf. Then, learners examine samples of oak leaves and work to classify them. This activity uses drawings of leaves, but it could also work with a collection of real leaves.

History, American M.

2001-01-01

65

Look at Those Leaves!  

NSDL National Science Digital Library

This Science NetLinks lesson begins with students observing leaves in a hands-on activity. As they observe attributes, they will group the leaves and consider any patterns they see emerge. In the second part of this lesson, students will become more familiar with the seasonal changing of leaves.

Science Netlinks;

2002-02-14

66

Graphing Fall Leaves  

NSDL National Science Digital Library

In this biology lab extension, student will have already collected leaves from the playground and surrounding school areas and sorted them into categories according to leaf properties. Students will use the leave classifications/ sorts to graph the properties of the leaves.

Bonnie DePeel

67

Forms of Leaves  

Microsoft Academic Search

IN a recent issue of NATURE, in the discussion on the forms of leaves, Mr. Henslow seems to doubt the assertion of Sir John Lubbock that the holly produces prickly leaves on the lower branches, and smooth leaves without spines above; but this is a fact which may easily be verified in numerous localities (selected gardens varieties are of course

R. A. Rolfe

1885-01-01

68

Essential oil composition of Piper guineense and its antimicrobial activity. Another chemotype from Nigeria.  

PubMed

The analysis of the essential oil of Piper guineense from Nigeria presents a new chemotype of constituents different from earlier reports with the absence of the usual myristicin. Ishwarane, a common constituent of Aristolochia indica and Bixa orellana, was also isolated from the essential oil of the fruit. The essential oil inhibited the growth of Pseudomonas aeruginosa UCH 655 strain at 5 mg/mL on which standard antibiotic drugs were ineffective. PMID:16041738

Oyedeji, O A; Adeniyi, B A; Ajayi, O; König, W A

2005-04-01

69

40 CFR 721.9530 - Bis(2,2,6,6-tetra-methyl-piper-idinyl) ester of cycloalkyl spir-o-ke-tal.  

Code of Federal Regulations, 2010 CFR

...6-tetra-methyl-piper-idinyl) ester of cycloalkyl spir-o-ke-tal. 721.9530 Section 721...6-tetra-methyl-piper-idinyl) ester of cycloalkyl spir-o-ke-tal. (a) Chemical substance...pi-per-idin-yl) ester of cy-clo-alkyl spir-o-ke-tal (PMN P-88-0083) is...

2010-07-01

70

Piper Sarmentosum Increases Nitric Oxide Production in Oxidative Stress: A Study on Human Umbilical Vein Endothelial Cells  

PubMed Central

OBJECTIVE: Nitric oxide produced by endothelial nitric oxide synthase (eNOS) possesses multiple anti-atherosclerotic properties. Hence, enhanced expression of eNOS and increased Nitric oxide levels may protect against the development of atherosclerosis. Piper sarmentosum is a tropical plant with antioxidant and anti-inflammatory activities. This study aimed to investigate the effects of Piper sarmentosum on the eNOS and Nitric oxide pathway in cultured human umbilical vein endothelial cells (HUVECs). METHODS: HUVECs were divided into four groups: control, treatment with 180 ?M hydrogen peroxide (H2O2), treatment with 150 ?g/mL aqueous extract of Piper sarmentosum, and concomitant treatment with aqueous extract of PS and H2O2 for 24 hours. Subsequently, HUVECs were harvested and eNOS mRNA expression was determined using qPCR. The eNOS protein level was measured using ELISA, and the eNOS activity and Nitric oxide level were determined by the Griess reaction. RESULTS: Human umbilical vein endothelial cells treated with aqueous extract of Piper sarmentosum showed a marked induction of Nitric oxide. Treatment with PS also resulted in increased eNOS mRNA expression, eNOS protein level and eNOS activity in HUVECs. CONCLUSION: Aqueous extract of Piper sarmentosum may improve endothelial function by promoting NO production in HUVECs. PMID:20668629

Ugusman, Azizah; Zakaria, Zaiton; Hui, Chua Kien; Nordin, Nor Anita Megat Mohd

2010-01-01

71

Types of Compound Leaves  

NSDL National Science Digital Library

This illustrated guide is designed to help students recognize and learn the different types of compound leaves. The single Web page can be easily printed for use at field sites. Along with a short description, an illustration that identifies a leaflet and petiole is included for four types of compound leaves.

72

Amygdalin in Prunus leaves  

Microsoft Academic Search

The cyanogenic diglucoside amygdalin was found for the first time in the leaves of mature trees of several Prunus taxa: P. serotina and P. virginiana cv. Schubert of subg. Padus and P. ilicifolia and P. lyonii of subg. Laurocerasus. Leaves of other taxa in both subgenera contained only the monoglucoside prunasin. Amygdalin production was inherited in hybrids between P. padus

Frank S. Santamour

1998-01-01

73

Types of Oak Leaves  

NSDL National Science Digital Library

This printable key to oak leaves helps students see the variety of shapes and sizes found within a plant family. The one-page PDF handout has 12 hand drawings of leaves. You can find the scientific names (genus and species) for all of them in the Biodiversity Counts Educators Guide.

74

Look At Those Leaves!  

NSDL National Science Digital Library

In this lesson, students will observe, measure, and sort tree leaves. They will examine leaves individually, in groups, and in relationship to the entire tree. As they observe attributes, they will group the leaves according to these attributes and consider any patterns that emerge. In addition, they will communicate what they have learned about leaves in quantitative terms. The activities in this lesson will challenge students to consider how standard units of measurement help clarify for others what they are trying to convey. In the second part of the lesson, students will become more familiar with the seasonal changing of leaves. They will realize that these and other changes repeat themselves and that these patterns of change are called cycles and are part of our environment.

75

MEDICAL LEAVE CHECKLIST EMPLOYEE RESPONSIBILITY  

E-print Network

MEDICAL LEAVE CHECKLIST EMPLOYEE RESPONSIBILITY 1. Discuss your Leave of Absence with your Supervisor. 2. For additional information on Leaves of Absence, and to obtain the UCF Medical Leave Request of Medical Leave Request Form" which is part of the Request form. Be sure you understand your

Wu, Shin-Tson

76

Falling for Clay Leaves.  

ERIC Educational Resources Information Center

Describes an art project that integrated science and art education. Explains that students create ceramic bowls by using real leaves. Discusses the process of creating the ceramic bowls, including how to glaze the bowls. Includes a list of materials. (CMK)

Kernan, Christine

2002-01-01

77

Nudibaccatumone, a trimer comprising a phenylpropanoid and two sesquiterpene moieties from Piper nudibaccatum.  

PubMed

A new complex natural product with a C39 skeleton, named nudibaccatumone, and the known sesquiterpenes (+)-spathulenol, (-)-4?,10?-aromadendranediol, and ent-T-muurolol, as well as the phenylpropanoid hydroxychavicol, were isolated from the aerial parts of Piper nudibaccatum. The structure and absolute configuration of nudibaccatumone were elucidated using spectroscopic methods and ECD calculations. A 1,8-Michael addition reaction and an intermolecular, inverse electron demand Diels-Alder reaction are proposed as the key steps in the biosynthesis of nudibaccatumone. PMID:23544451

Liu, Hong-Xin; Chen, Kai; Sun, Qian-Yun; Yang, Fu-Mei; Hu, Guang-Wan; Wang, Yue-Hu; Long, Chun-Lin

2013-04-26

78

Leaves and Air Pollution  

NSDL National Science Digital Library

In this activity, students investigate the effects of automobile pollution on plant growth by making measurements on two populations of leaves, one from within 10 meters of a busy road and a population of the same species situated more than 20 meters away. They will choose a method for measuring the leaves, create a table for their data, and test their hypotheses by performing a t-test.

Laposata, Matt

79

Describing Oak Leaves  

NSDL National Science Digital Library

In this Biodiversity Counts activity, students examine drawings of oak leaves and figure out how to classify and identify them. The printable six-page PDF handout includes a series of inquiry-based questions to get students thinking about what they already know about classification and its importance to scientists, drawings of 12 different oak leaves, and a worksheet that includes step-by-step directions and areas for recording answers.

80

Piperine production by endophytic fungus Colletotrichum gloeosporioides isolated from Piper nigrum.  

PubMed

Many endophytic fungi have been reported with the biosynthetic potential to produce same or similar metabolites present in host plants. The adaptations that might have acquired by these fungi as a result of the long-term association with their host plants can be the possible basis of their biosynthetic potential. The bioactive compounds originated from endophytes are currently explored for their potential applications in pharmaceutical, agriculture and food industries. Piper nigrum, a plant of the Piperaceae is very remarkable because of the presence of the alkaloid piperine. Piperine has been reported to have broad bioactive properties ranging from antimicrobial, antidepressant, anti-inflammatory, antioxidative to anticancer activities. Interestingly, piperine also plays a vital role in increasing the bioavailability of many drugs which again is a promising property. The current study was carried out to identify piperine producing endophytic fungus from Piper nigrum L. By screening various endophytic fungi, the isolate which was identified as member of Colletotrichum gloeosporioides was found to have the ability to form piperine and was confirmed by HPLC and LCMS. Considering the broad bioactive potential of piperine, the piperine producing fungi identified in the study can expect to have much industrial potential. PMID:24268806

Chithra, S; Jasim, B; Sachidanandan, P; Jyothis, M; Radhakrishnan, E K

2014-03-15

81

Synchronous EMG activity in the Piper frequency band reveals the corticospinal demand of walking tasks  

PubMed Central

Evidence indicates that the frequency-domain characteristics of surface electromyogram (EMG) signals are modulated according to the contributing sources of neural drive. Modulation of inter-muscular EMG synchrony within the Piper frequency band (30–60Hz) during movement tasks has been linked to drive from the corticospinal tract. However, it is not known whether EMG synchrony is sufficiently sensitive to detect task-dependent differences in the corticospinal contribution to leg muscle activation during walking. We investigated this question in seventeen healthy older men and women. It was hypothesized that, relative to typical steady state walking, Piper band EMG synchrony of the triceps surae muscle group would be reduced for dual-task walking (because of competition for cortical resources), similar for fast walking (because walking speed is directed by an intermediate locomotor pathway rather than by the corticospinal tract), and increased when taking a long step (because voluntary gait pattern modifications are directed by the corticospinal tract). Each of these hypotheses was confirmed. These findings support the use of frequency-domain analysis of EMG in future investigations into the corticospinal contribution to control of healthy and disordered human walking. PMID:23740367

Clark, David J.; Kautz, Steven A.; Bauer, Andrew R.; Chen, Yen-Ting; Christou, Evangelos A.

2013-01-01

82

The complete genome sequence of Piper yellow mottle virus (PYMoV).  

PubMed

This study reports the first complete genome sequence of Piper yellow mottle virus (PYMoV, KC808712) identified in black pepper. The genome is 7,622 nucleotides long, possessing four open reading frames (ORFs). ORF1, ORF2 and ORF4 of PYMoV are reported as hypothetical proteins of unknown function with a predicted molecular mass of 15.7, 17.1 and 17.9 kDa, respectively. ORF3 of PYMoV encodes a polyprotein of 218.6 kDa and consists of a viral movement protein (MP), trimeric dUTPase, zinc finger, retropepsin, RT-LTR, and RNAse H. Detailed PYMoV genome analysis confirmed that it is a member of the family Caulimoviridae, genus Badnavirus. Fragments of two additional novel sequences resembling those found in members of the family Caulimoviridae were also identified in the black pepper sample, and the viruses from which they were derived were tentatively named Piper DNA virus 1 and 2. PMID:24005374

Hany, U; Adams, I P; Glover, R; Bhat, A I; Boonham, N

2014-02-01

83

Docking with PIPER and refinement with SDU in rounds 6-11 of CAPRI.  

PubMed

Our approach to protein-protein docking includes three main steps. First we run PIPER, a new rigid body docking program. PIPER is based on the Fast Fourier Transform (FFT) correlation approach that has been extended to use pairwise interactions potentials, thereby substantially increasing the number of near-native structures generated. The interaction potential is also new, based on the DARS (Decoys As the Reference State) principle. In the second step, the 1000 best energy conformations are clustered, and the 30 largest clusters are retained for refinement. Third, the conformations are refined by a new medium-range optimization method SDU (Semi-Definite programming based Underestimation). SDU has been developed to locate global minima within regions of the conformational space in which the energy function is funnel-like. The method constructs a convex quadratic underestimator function based on a set of local energy minima, and uses this function to guide future sampling. The combined method performed reliably without the direct use of biological information in most CAPRI problems that did not require homology modeling, providing acceptable predictions for targets 21, and medium quality predictions for targets 25 and 26. PMID:17853451

Shen, Yang; Brenke, Ryan; Kozakov, Dima; Comeau, Stephen R; Beglov, Dmitri; Vajda, Sandor

2007-12-01

84

Smart Card Security Kostas Markantonakis I.1, Keith Mayes I.2, Michael Tunstall I.3, Fred Piper I.4,  

E-print Network

Chapter I Smart Card Security Kostas Markantonakis I.1, Keith Mayes I.2, Michael Tunstall I.3, Fred Piper I.4, and Damien Sauveron I.5 I.6 . I.1 Introduction I.2 Smart cards and Cryptography I.3 Smart card Specific Attacks Sensitive systems that are based on smart cards use protocols and algorithms

Mayes, Keith

85

Soil seed banks and growth rates of an invasive species, Piper aduncum, in the lowlands of Papua New Guinea  

Microsoft Academic Search

Secondary fallow vegetation in parts of the Papua New Guinea lowlands is dominated by the shrub Piper aduncum L. that originates from South America. Here we report on its seed bank, growth rate and biomass accumulation. P. aduncum accounted for 69 % (408 m[minus sign]2) of the seed bank in the forest and 53 % (1559 m[minus sign]2) of the

Howard M. Rogers; Alfred E. Hartemink

2000-01-01

86

Geographic Variation in Host-Specificity and Parasitoid Pressure of an Herbivore (Geometridae) Associated with the Tropical Genus Piper (Piperaceae)  

PubMed Central

The extraordinary diversity of tropical herbivores may be linked to hostplant specialization driven in part by variation in pressure from natural enemies. We quantified levels of host-specificity and parasitoid attack for the specialist herbivore, Eois (Geometridae). The goals of this research were to examine: 1) whether Eois are specialized on the genus Piper (Piperaceae) and if hostplant specialization varies geographically; 2) whether Eois are equally vulnerable to parasitoid attack across different geographic regions and by the same parasitoid families; and 3) whether parasitism levels vary with precipitation and elevation. Based on over 15,000 rearings, we found Eois caterpillars feeding exclusively on Piper. However, we did not detect geographic differences in host-specificity; each Eois species fed on an average of two Piper species. Parasitism levels of Eois varied significantly with climate and topography; Eois were most vulnerable to parasitoid attack in moist versus dry and wet forests and at low versus high elevations. The diversity of parasitoid families reared from Eois was greater in Ecuador and Costa Rica than in Panama, where parasitoids were primarily in the family Braconidae. The quantitative evidence for host-specificity provides support for the hypothesis that Eois are specialized on Piper. Our results also reveal that Eois are exposed to a mosaic of potential selective pressures due to variation in parasitoid attack over a large spatial scale. PMID:19613860

Connahs, Heidi; Rodríguez-Castañeda, Genoveva; Walters, Toni; Walla, Thomas; Dyer, Lee

2009-01-01

87

Healing property of the Piper betel phenol, allylpyrocatechol against indomethacin-induced stomach ulceration and mechanism of action  

Microsoft Academic Search

AIM: To evaluate the protective activity of allylpyrocatechol (APC), the major antioxidant constituent of Piper betel , against the indomethacin-induced stomach ulceration in the rat model and correlates with its antioxidative and mucin protecting properties. METHODS: Male Sprague-Dawley rats were divided into five groups. Normal control rats (group ?) were given the vehicle oral dose of gum acacia in distilled

S Bhattacharya; D Banerjee; AK Bauri; S Chattopadhyay; B. C. Roy; Sandip K Bandyopadhyay; Acharya Jagadish

88

Leaves: Nature's Solar Collectors  

ERIC Educational Resources Information Center

One of the most captivating things about plants is the way they capture the Sun's energy, but this can be a difficult topic to cover with elementary students. Therefore, to help students to make a concrete connection to this abstract concept, this series of solar-energy lessons focuses on leaves and how they act as "solar collectors." As students…

Isabelle, Aaron D.; de Groot, Cornelis

2009-01-01

89

Maternity Leave in Taiwan  

PubMed Central

Using the first nationally representative birth cohort study in Taiwan, this paper examines the role that maternity leave policy in Taiwan plays in the timing of mothers returning to work after giving birth, as well as the extent to which this timing is linked to the amount of time mothers spend with their children and their use of breast milk versus formula. We found that the time when mothers returned to work coincided with the duration of guaranteed leave. In particular, mothers with a labor pension plan resumed work significantly earlier than mothers with no pension plan, and mothers with no pension plan returned to work significantly later than those with pension plans. The short leave of absence guaranteed under existing policies translated into mothers spending less time with their children and being more likely to exclusively use formula by 6 months after birth. In contrast, mothers who resumed work later than 6 months after birth were more likely to have not worked before birth or to have quit their jobs during pregnancy. Implications and recommendations for parental leave policy in Taiwan are discussed. PMID:21603074

Feng, Joyce Yen; Han, Wen-Jui

2011-01-01

90

Maternity Leave in Taiwan  

ERIC Educational Resources Information Center

Using the first nationally representative birth cohort study in Taiwan, this paper examines the role that maternity leave policy in Taiwan plays in the timing of mothers returning to work after giving birth, as well as the extent to which this timing is linked to the amount of time mothers spend with their children and their use of breast milk…

Feng, Joyce Yen; Han, Wen-Jui

2010-01-01

91

Paper Chromatography with Leaves  

NSDL National Science Digital Library

In this activity on page 5 of the PDF, learners use chromatography to separate and identify pigments within various leaves. Learners soak leaf pieces in warmed rubbing alcohol and then dip coffee filter paper in the alcohol, lifting and separating the leaf pigments according to size.

2013-07-08

92

Rapid detection of Piper yellow mottle virus and Cucumber mosaic virus infecting black pepper (Piper nigrum) by loop-mediated isothermal amplification (LAMP).  

PubMed

The loop-mediated isothermal amplification (LAMP) assay for Piper yellow mottle virus and the reverse transcription (RT) LAMP assay for Cucumber mosaic virus each consisted of a set of five primers designed against the conserved sequences in the viral genome. Both RNA and DNA isolated from black pepper were used as a template for the assay. The results were assessed visually by checking turbidity, green fluorescence and pellet formation in the reaction tube and also by gel electrophoresis. The assay successfully detected both viruses in infected plants whereas no cross-reactions were recorded with healthy plants. Optimum conditions for successful amplification were determined in terms of the concentrations of magnesium sulphate and betaine, temperature, and duration. The detection limit for both LAMP and RT-LAMP was up to 100 times that for conventional PCR and up to one-hundredth of that for real-time PCR. The optimal conditions arrived at were validated by testing field samples of infected vines of three species from different regions. PMID:23791964

Bhat, A I; Siljo, A; Deeshma, K P

2013-10-01

93

Compounds from the aerial parts of Piper bavinum and their anti-cholinesterase activity.  

PubMed

A new alkenylphenol, bavinol A (1), together with six known compounds (2-7) were isolated from the aerial parts of Piper bavinum (Piperaceae). The chemical structures of these compounds were determined by spectroscopic analyses including 2D NMR spectroscopy. The anti-Alzheimer effects of compounds 1-7 were evaluated from acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activity assays. Bavinol A (1), ampelopsin (3), and violanthin (4) exhibited AChE inhibitory activities with IC50 values of 29.80, 59.47 and 79.80 ?M. Compound 1 also showed the most potent BChE inhibitory activity with an IC50 value of 19.25 ?M. PMID:25005067

Dung, Hoang Viet; Cuong, To Dao; Chinh, Nguyen Minh; Quyen, Do; Kim, Jeong Ah; Byeon, Jeong Su; Woo, Mi Hee; Choi, Jae Sui; Min, Byung Sun

2014-07-01

94

Preventable disasters in the offshore oil industry: from Piper Alpha to Deepwater Horizon.  

PubMed

This article compares two industrial disasters in the offshore oil industry, the explosion and fire on Piper Alpha off the coast of Scotland in 1988, the world's worst offshore disaster, and the blowout and explosions on Deepwater Horizon in the Gulf of Mexico in 2010. It attempts to answer a simple question: Given the enormity of the first tragedy and the careful analysis of its circumstances and causes, why were the lessons of previous failure not learned by this globally organized industry, in the very heartland in the United States? The answer tells us much about the ability of corporate capital to configure regulatory regimes in its own interests and to do so in a manner that continues to threaten the safety and well-being of its employees and the wider environment. PMID:23384815

Woolfson, Charles

2012-01-01

95

Novel compounds from Piper methysticum Forst (Kava Kava) roots and their effect on cyclooxygenase enzyme.  

PubMed

Milled Piper methysticum roots were extracted sequentially with hot water and methanol. Cyclooxygenase (COX) enzyme inhibitory assay directed purification of the methanol extract yielded bornyl esters of 3,4-methylenedioxy cinnamic acid (1) and cinnamic acid (2), pinostrobin (3), flavokawain B (4), and 5,7-dimethoxyflavanone (5). The structures of compounds 1-5 were accomplished by spectral experiments. The aqueous extract contained previously reported kava lactones, as confirmed by TLC analysis. Compounds 3 and 5 were isolated for the first time from kava kava roots. Compound 4 showed the highest COX-I inhibitory activity at 100 microg/mL. All the compounds tested gave good COX-I and moderate COX-II enzyme inhibitory activities at 100 microg/mL. This is the first report of COX-I and -II inhibitory activities for compounds 1-5. PMID:11829631

Wu, Di; Nair, Muraleedharan G; DeWitt, David L

2002-02-13

96

Neolignans and phenylpropanoids from the roots of Piper taiwanense and their antiplatelet and antitubercular activities.  

PubMed

Bioassay-guided fractionation of roots from Piper taiwanense led to isolation of three neolignans, diallylcatechol (1) and neotaiwanensols A, B (2, 3), two diphenylpropanoid ethers, taiwandimerols A, B (4, 5), with one phenylpropanoid, 2,3-diacetoxy-1-methoxy-5-allylbenzene (6), previously unknown in nature, together with 18 known compounds (7-24). Their structures were elucidated by spectroscopic evidence. Among the isolates, hydroxychavicol acetate (7), and 4-allylcatechol (8) showed potent inhibitory activities against platelet aggregation induced by collagen, with IC50 values of 2.1, and 5.3 ?M, respectively. Hydroxychavicol acetate (7), 4-allylcatechol (8), and trans-caffeicaldehyde (9) showed antitubercular activities against Mycobacterium tuberculosis H37Rv, with MIC values of 30.3, 27.6, and 25.5 ?g/mL, respectively. PMID:23582215

Chen, Si; Huang, Hung-Yi; Cheng, Ming-Jen; Wu, Chin-Chung; Ishikawa, Tsutomu; Peng, Chien-Fang; Chang, Hsun-Shou; Wang, Chyi-Jia; Wong, Su-Ling; Chen, Ih-Sheng

2013-09-01

97

Classify the trees/Leaves  

NSDL National Science Digital Library

This activity is a field investigation where students gather leaves from various trees on school property, interpret findings, name tree and leaves, journal activity and develop a new "aha" for nature!

Mary Walsh

98

Complete plastid genome sequences of Drimys, Liriodendron, and Piper: implications for the phylogenetic relationships of magnoliids  

PubMed Central

Background The magnoliids with four orders, 19 families, and 8,500 species represent one of the largest clades of early diverging angiosperms. Although several recent angiosperm phylogenetic analyses supported the monophyly of magnoliids and suggested relationships among the orders, the limited number of genes examined resulted in only weak support, and these issues remain controversial. Furthermore, considerable incongruence resulted in phylogenetic reconstructions supporting three different sets of relationships among magnoliids and the two large angiosperm clades, monocots and eudicots. We sequenced the plastid genomes of three magnoliids, Drimys (Canellales), Liriodendron (Magnoliales), and Piper (Piperales), and used these data in combination with 32 other angiosperm plastid genomes to assess phylogenetic relationships among magnoliids and to examine patterns of variation of GC content. Results The Drimys, Liriodendron, and Piper plastid genomes are very similar in size at 160,604, 159,886 bp, and 160,624 bp, respectively. Gene content and order are nearly identical to many other unrearranged angiosperm plastid genomes, including Calycanthus, the other published magnoliid genome. Overall GC content ranges from 34–39%, and coding regions have a substantially higher GC content than non-coding regions. Among protein-coding genes, GC content varies by codon position with 1st codon > 2nd codon > 3rd codon, and it varies by functional group with photosynthetic genes having the highest percentage and NADH genes the lowest. Phylogenetic analyses using parsimony and likelihood methods and sequences of 61 protein-coding genes provided strong support for the monophyly of magnoliids and two strongly supported groups were identified, the Canellales/Piperales and the Laurales/Magnoliales. Strong support is reported for monocots and eudicots as sister clades with magnoliids diverging before the monocot-eudicot split. The trees also provided moderate or strong support for the position of Amborella as sister to a clade including all other angiosperms. Conclusion Evolutionary comparisons of three new magnoliid plastid genome sequences, combined with other published angiosperm genomes, confirm that GC content is unevenly distributed across the genome by location, codon position, and functional group. Furthermore, phylogenetic analyses provide the strongest support so far for the hypothesis that the magnoliids are sister to a large clade that includes both monocots and eudicots. PMID:17020608

Cai, Zhengqiu; Penaflor, Cynthia; Kuehl, Jennifer V; Leebens-Mack, James; Carlson, John E; dePamphilis, Claude W; Boore, Jeffrey L; Jansen, Robert K

2006-01-01

99

Intrinsic anticarcinogenic effects of Piper sarmentosum ethanolic extract on a human hepatoma cell line  

PubMed Central

Background Piper sarmentosum, locally known as kaduk is belonging to the family of Piperaceae. It is our interest to evaluate their effect on human hepatoma cell line (HepG2) for the potential of anticarcinogenic activity. Results The anticarcinogenic activity of an ethanolic extract from Piper sarmentosum in HepG2 and non-malignant Chang's liver cell lines has been previously determined using (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide) (MTT) assays, where the IC50 value was used as a parameter for cytotoxicity. The ethanolic extract that showed anticarcinogenic properties in HepG2 cells had an IC50 of 12.5 ?g mL-1, while IC50 values in the non-malignant Chang's liver cell line were greater than 30 ?g mL-1. Apoptotic morphological changes in HepG2 cells were observed using an inverted microscope and showed chromatin condensation, cell shrinkage and apoptotic bodies following May-Grunwald-Giemsa's staining. The percentage of apoptotic cells in the overall population (apoptotic index) showed a continuously significant increase (p < 0.05) in 12.5 ?g mL-1 ethanolic extract-treated cells at 24, 48 and 72 hours compared to controls (untreated cells). Following acridine orange and ethidium bromide staining, treatment with 10, 12 and 14 ?g mL-1 of ethanolic extracts caused typical apoptotic morphological changes in HepG2 cells. Molecular analysis of DNA fragmentation was used to examine intrinsic apoptosis induced by the ethanolic extracts. These results showed a typical intrinsic apoptotic characterisation, which included fragmentation of nuclear DNA in ethanolic extract-treated HepG2 cells. However, the non-malignant Chang's liver cell line produced no DNA fragmentation. In addition, the DNA genome was similarly intact for both the untreated non-malignant Chang's liver and HepG2 cell lines. Conclusion Therefore, our results suggest that the ethanolic extract from P. sarmentosum induced anticarcinogenic activity through an intrinsic apoptosis pathway in HepG2 cells in vitro. PMID:19257877

Zainal Ariffin, Shahrul Hisham; Wan Omar, Wan Haifa Haryani; Zainal Ariffin, Zaidah; Safian, Muhd Fauzi; Senafi, Sahidan; Megat Abdul Wahab, Rohaya

2009-01-01

100

Evaluation of antioxidant, antibacterial and cytotoxic effects of green synthesized silver nanoparticles by Piper longum fruit.  

PubMed

Silver nanoparticles synthesized through bio-green method has been reported to have biomedical applications to control pathogenic microbes as it is cost effective compared to commonly used physical and chemical methods. In present study, silver nanoparticles were synthesized using aqueous Piper longum fruit extract (PLFE) and confirmed by UV-visible spectroscopy. The nanoparticles were spherical in shape with an average particle size of 46nm as determined by scanning electronic microscopy (SEM) and dynamic light scattering (DLS) particle size analyzer respectively. FT-IR spectrum revealed the capping of the phytoconstituents, probably polyphenols from P. longum fruit extract and stabilizing the nanoparticles. Further the ferric ion reducing test, confirmed that the capping agents were condensed tannins. The aqueous P. longum fruit extract (PLFE) and the green synthesized silver nanoparticles (PLAgNPs) showed powerful antioxidant properties in in vitro antioxidant assays. The results from the antimicrobial assays suggested that green synthesized silver nanoparticles (PLAgNPs) were more potent against pathogenic bacteria than the P. longum fruit extract (PLFE) alone. The nanoparticles also showed potent cytotoxic effect against MCF-7 breast cancer cell lines with an IC 50 value of 67?g/ml/24h by the MTT assay. These results support the advantages of using bio-green method for synthesizing silver nanoparticles with antioxidant, antimicrobial and cytotoxic activities those are simple and cost effective as well. PMID:24268240

Reddy, N Jayachandra; Nagoor Vali, D; Rani, M; Rani, S Sudha

2014-01-01

101

Acaricide activity of different extracts from Piper tuberculatum fruits against Rhipicephalus microplus.  

PubMed

Rhipicephalus microplus is the main tick that affects cattle. Plant bioactive molecules can be used to control this ectoparasite. The aim of this study was to evaluate the in vitro efficacy of Piper tuberculatum fruit extracts obtained with different solvents on R. microplus larvae and engorged females. Hexane, ethyl ether, ethanolic, and methanolic extracts of P. tuberculatum fruits were evaluated. After extraction, all of the extracts were dried. Adult immersion tests and larval packet tests were performed with five different concentrations of each of the extracts. The hexane extracts of P. tuberculatum showed the highest larvicidal activity against R. microplus (lethal concentration (LC50 = 0.04 mg/mL), followed by the ethyl ether (LC50 = 0.08 mg/mL), ethanolic (LC50 = 2.73 mg/mL), and methanolic (LC50 = 4.49 mg/mL) extracts. The P. tuberculatum fruit extracts were also effective against R. microplus-engorged females. Ethyl acetate extracts showed the highest efficiency (LC50 = 18.4 mg/mL), followed by the methanolic (LC50 = 105.6 mg/mL), ethanolic (LC50 = 140.0 mg/mL), and hexane (LC50 = 297.4 mg/mL) extracts. All of the extracts showed similar chromatographic profiles containing 24% piperine. The P. tuberculatum fruit extracts contain bioactive compounds with great potential to improve the standard formulations of acaricides for the control of R. microplus. PMID:24221883

Lima, Aldilene da Silva; Sousa Filho, José Gracione do Nascimento; Pereira, Sinval Garcia; Guillon, Giselle Maria Skelding Pinheiro; Santos, Lourivaldo da Silva; Costa Júnior, Livio Martins

2014-01-01

102

[Potential allelopathic effects of Piper nigrum, Mangifera indica and Clausena lansium].  

PubMed

With Piper nigrum, Mangifera indica and Clausena lansium as the donators, this paper studied their potential allelopathic effects on the germination and growth of Zea mays, Glycine max, Cucurbita moschata, Arachis hypogaea, Raphanus sativus, Echinochloa crusgalli, Digitaria sanguinalis and Stylosanthes guianensis. The results showed that the aqueous extracts of these donators could inhibit the germination and growth of Z. mays, G. max, C. moschata, E. crus-galli and D. sanguinalis at high concentration, but stimulate them at low concentration. In rhizosphere soil of P. nigrum and M. indica, the germination and growth of Z. mays L was stimulated, while A. hypogaea was inhibited. The aqueous extracts of the donators were extracted by ethyl acetate and n-butanol, respectively, and the inhibitory activity of both aqueous and n-butanol fractions from P. nigrum and M. indica on Z. mays, R. sativus and S. guianensis was stronger than that of ethyl acetate fraction, indicating that P. nigrum and M. indica contained the allelochemicals with high polarity. PMID:17147171

Yan, Guijun; Zhu, Chaohua; Luo, Yanping; Yang, Ye; Wei, Jinju

2006-09-01

103

Antitumour Efficacy of Piper tuberculatum and Piplartine Based on the Hollow Fiber Assay.  

PubMed

Piper tuberculatum, popularly known in Brazil as "jaborandi falso" and "pimenta darta", is widely used in folk medicine for the treatment of several diseases. In this study, the in vivo hollow fiber assay was used to investigate the antitumour efficacy of the crude extract and piplartine obtained from P. tuberculatum roots. Human glioblastoma (SF-295) and colon carcinoma (HCT-8) cell lines were used. In vitro cytotoxicity was assayed by the MTT assay. In the hollow fiber assay, nude mice implanted with tumour cells in hollow fibers were treated for four consecutive days via the intraperitoneal route, and tumour cell populations were assessed by the MTT assay. Both the crude extract and piplartine displayed cytotoxicity. In the hollow fiber assay, tumour growth inhibition rates were 24.6-54.8?% for the crude extract and 33.7-62.2?% for piplartine. No signal of toxicity was noticed. In conclusion, the crude extract and piplartine obtained from P. tuberculatum roots displayed in vitro and in vivo anticancer efficacy. PMID:25519832

Bezerra, Daniel P; Ferreira, Paulo Michel P; Machado, Camila Maria L; de Aquino, Nayara C; Silveira, Edilberto R; Chammas, Roger; Pessoa, Claudia

2015-01-01

104

Bioassay-guided Isolation of Constituents of Piper sarmentosum Using a Mitochondrial Transmembrane Potential Assay  

PubMed Central

Bioassay-guided fractionation was conducted on a chloroform-soluble extract of the aerial parts of Piper sarmentosum collected in Vietnam, monitored by a mitochondrial transmembrane potential (MTP) assay using HT-29 human colon cancer cells. This led to the isolation of four new C-benzylated dihydroflavones, sarmentosumins A-D (1-4), as well as 14 known compounds. The structures of the new compounds were elucidated on the basis of spectroscopic data interpretation. Among these compounds, 1-4 as well as five known C-benzylated dihydroflavones (5-9), and pipercallosine, a piperamide (11), were found to induce apoptosis in HT-29 cells by moderately reducing the mitochondrial transmembrane potential (??m), with ED50 values ranging from 1.6 to 13.6 ?M. Furthermore, 7-methoxydichamanetin (8) and pinocembrin (10) exhibited proteasome inhibitory activities in a human 20S proteasome bioassay with IC50 values of 3.45 ± 0.18 ?M and 2.87 ± 0.26 ?M, respectively. This is the first time that C-benzylated dihydroflavones have been reported to demonstrate an apoptotic effect associated with disruption of the mitochondrial transmembrane potential. PMID:21973101

Pan, Li; Matthew, Susan; Lantvit, Daniel D.; Zhang, Xiaoli; Ninh, Tran Ngoc; Chai, Heebyung; de Blanco, Esperanza J. Carcache; Soejarto, Djaja D.; Swanson, Steven M.; Kinghorn, A. Douglas

2011-01-01

105

Efficacy of extracting solvents to chemical components of kava (Piper methysticum) roots.  

PubMed

The chemical composition of kava (Piper methysticum) lactones and various phytochemicals obtained following the sonication of ground kava roots extracted in the solvents hexane, chloroform, acetone, ethanol, methanol and water, respectively, was analyzed. Eighteen kava lactones, cinnamic acid bornyl ester and 5,7-dimethoxy-flavanone, known to be present in kava roots, were identified, and seven compounds, including 2,5,8-trimethyl-1-naphthol, 5-methyl-1-phenylhexen-3-yn-5-ol, 8,11-octadecadienoic acid-methyl ester, 5,7-(OH)(2)-4'-one-6,8-dimethylflavanone, pinostrobin chalcone and 7-dimethoxyflavanone-5-hydroxy-4', were identified for the first time. Glutathione (26.3 mg/g) was found in the water extract. Dihydro-5,6-dehydrokavain (DDK) was present at a higher level than methysticin and desmethoxyyagonin, indicating that DDK is also a major constituent of kava roots. Acetone was the most effective solvent in terms of maximum yield and types of kava lactones isolated, followed by water and chloroform, whereas hexane, methanol, and ethanol were less effective as solvents. Total phenolic and antioxidant activity varied among the extracting solvents, with acetone and chloroform producing the highest effects, followed by water, while methanol, ethanol and hexane were less effective. PMID:18404321

Xuan, Tran Dang; Fukuta, Masakazu; Wei, Ao Chang; Elzaawely, Abdelnaser Abdelghany; Khanh, Tran Dang; Tawata, Shinkichi

2008-04-01

106

Chemical compositions, antioxidant and antimicrobial activity of the essential oils of Piper officinarum (Piperaceae).  

PubMed

This study was designed to investigate the antioxidant and antimicrobial activities of the essential oils from Piper officinarum C. DC. GC and GC/MS analysis of the leaf and stem oils showed forty one components, representing 85.6% and 93.0% of the oil, respectively. The most abundant components in the leaf oil were beta-caryophyllene (11.2%), alpha-pinene (9.3%), sabinene (7.6%), beta-selinene (5.3%) and limonene (4.6%), while beta-caryophyllene (10.9%), alpha-phellandrene (9.3%), linalool (6.9%), limonene (6.7%) and alpha-pinene (5.0%) were the main components of the stem oil. The antioxidant activities were determined by using complementary tests: namely beta-carotene-linoleic acid, DPPH radical scavenging and total phenolic assays. The stems oil showed weak activity (IC50 = 777.4 microg/mL) in the DPPH system, but showed moderate lipid peroxidation inhibition in the beta-carotene-linoleic acid system (88.9 +/- 0.35%) compared with BHT (95.5 +/- 0.30%). Both oils showed weak activity against P. aeruginosa and E. coli with M IC values of 250 microg/mL. PMID:23413576

Salleh, Wan Mohd Nuzul Hakimi Wan; Ahmad, Farediah; Yen, Khong Heng; Sirat, Hasnah Mohd

2012-12-01

107

Growth and survival of Salmonella in ground black pepper (Piper nigrum).  

PubMed

A four serovar cocktail of Salmonella was inoculated into ground black pepper (Piper nigrum) at different water activity (aw) levels at a starting level of 4-5 log cfu/g and incubated at 25 and at 35 °C. At 35 °C and aw of 0.9886 ± 0.0006, the generation time in ground black pepper was 31 ± 3 min with a lag time of 4 ± 1 h. Growth at 25 °C had a longer lag, but generation time was not statistically different from growth at 35 °C. The aw threshold for growth was determined to be 0.9793 ± 0.0027 at 35 °C. To determine survival during storage conditions, ground black pepper was inoculated at approximately 8 log cfu/g and stored at 25 and 35 °C at high (97% RH) and ambient (?40% RH) humidity. At high relative humidity, aw increased to approximately 0.8-0.9 after approximately 20 days at both temperatures and no Salmonella was detected after 100 and 45 days at 25 and 35 °C, respectively. Under ambient humidity, populations showed an initial decrease of 3-4 log cfu/g, then remained stable for over 8 months at 25 and 35 °C. Results of this study indicate Salmonella can readily grow at permissive aw in ground black pepper and may persist for an extended period of time under typical storage conditions. PMID:23498196

Keller, Susanne E; VanDoren, Jane M; Grasso, Elizabeth M; Halik, Lindsay A

2013-05-01

108

Selective Effect of 2?,6?-Dihydroxy-4?-Methoxychalcone Isolated from Piper aduncum on Leishmania amazonensis  

PubMed Central

2?,6?-Dihydroxy-4?-methoxychalcone (DMC) was purified from the dichloromethane extract of Piper aduncum inflorescences. DMC showed significant activity in vitro against promastigotes and intracellular amastigotes of Leishmania amazonensis, with 50% effective doses of 0.5 and 24 ?g/ml, respectively. Its inhibitory effect on amastigotes is apparently a direct effect on the parasites and is not due to activation of the nitrogen oxidative metabolism of macrophages, since the production of nitric oxide by both unstimulated and recombinant gamma interferon-stimulated macrophages was decreased rather than increased with DMC. The phagocytic activity of macrophages was functioning normally even with DMC concentrations as high as 80 ?g/ml, as seen by electron microscopy and by the uptake of fluorescein isothiocyanate-labeled beads. Ultrastructural studies also showed that in the presence of DMC the mitochondria of promastigotes were enlarged and disorganized. Despite destruction of intracellular amastigotes, no disarrangement of macrophage organelles were observed, even at 80 ?g of DMC/ml. These observations suggest that DMC is selectively toxic to the parasites. Its simple structure may well enable it to serve as a new lead compound for the synthesis of novel antileishmanial drugs. PMID:10223942

Torres-Santos, Eduardo Caio; Moreira, Davyson Lima; Kaplan, Maria Auxiliadora C.; Meirelles, Maria Nazareth; Rossi-Bergmann, Bartira

1999-01-01

109

Shelter-building behavior and natural history of two pyralid caterpillars feeding on Piper stipulaceum.  

PubMed

Shelter-building behavior by caterpillars provides a mechanism of defense against predators, microenvironment enhancement, and in some cases nutritional benefits. This study provides a detailed description of the life cycle and shelter-building process of caterpillars, and identifies constraints and factors influencing this adaptive behavior in Lepidomys n. sp. near proclea Druce (Pyralidae: Chrysauginae), a tropical dry forest pyralid. Five macroscopic larval instars were detected during the life cycle, and activities performed during shelter-building were categorized and timed. Caterpillar predators were identified, and 20% of all collected larvae died due to attack by parasitoid wasps. Shelter-building behavior was found to be constrained by the ontogenetic stage of caterpillars and influenced by leaf size of the host plant, Piper stipulaceum Opiz (Piperales: Piperaceae) . A similar pattern of shelter-building behavior exhibited by Tosale n. sp. near cuprealis larvae that coexisted in the same host plant is also described. Larvae of the second species were significantly less abundant than those of Lepidomys and hatched one month later in the rainy season, which could indicate some competitive interactions between these two pyralid species. PMID:25373186

Abarca, Mariana; Boege, Karina; Zaldívar-Riverón, Alejandro

2014-01-01

110

PIPER: an FFT-based protein docking program with pairwise potentials.  

PubMed

The Fast Fourier Transform (FFT) correlation approach to protein-protein docking can evaluate the energies of billions of docked conformations on a grid if the energy is described in the form of a correlation function. Here, this restriction is removed, and the approach is efficiently used with pairwise interaction potentials that substantially improve the docking results. The basic idea is approximating the interaction matrix by its eigenvectors corresponding to the few dominant eigenvalues, resulting in an energy expression written as the sum of a few correlation functions, and solving the problem by repeated FFT calculations. In addition to describing how the method is implemented, we present a novel class of structure-based pairwise intermolecular potentials. The DARS (Decoys As the Reference State) potentials are extracted from structures of protein-protein complexes and use large sets of docked conformations as decoys to derive atom pair distributions in the reference state. The current version of the DARS potential works well for enzyme-inhibitor complexes. With the new FFT-based program, DARS provides much better docking results than the earlier approaches, in many cases generating 50% more near-native docked conformations. Although the potential is far from optimal for antibody-antigen pairs, the results are still slightly better than those given by an earlier FFT method. The docking program PIPER is freely available for noncommercial applications. PMID:16933295

Kozakov, Dima; Brenke, Ryan; Comeau, Stephen R; Vajda, Sandor

2006-11-01

111

Effects of Piper hispidinervum on spermatogenesis and histochemistry of ovarioles of Spodoptera frugiperda.  

PubMed

The fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), not only damages crops, but controlling its population also requires synthetic insecticides, which leads to selection of resistant populations and environmental contamination. Essential oils are an alternative for controlling this insect. There are few studies of the effects of these oils on the insect's reproductive system. We evaluated the effects of the long pepper, Piper hispidinervum, essential oil on the gonads of the armyworm and tested its possible influence on the fertility of this insect. Dosages of 30 and 50 mg/ml were tested in 3(rd) instar caterpillars using the leaf immersion method. Testes and ovarioles were collected, fixed with 10% formalin and embedded in Historesin. The sections were stained with toluidine blue and Mallory trichrome to detect connective tissue, periodic acid-Schiff to detect neutral carbohydrates, and bromophenol blue to detect proteins. We found that the long pepper essential oil affected negatively the spermatogenesis and altered the histochemistry of the ovarioles of S. frugiperda. The effects of long pepper oil suggest that it is a promising tool for controlling the armyworm pest. PMID:24106972

Alves, T J S; Cruz, G S; Wanderley-Teixeira, V; Teixeira, A A C; Oliveira, J V; Correia, A A; Câmara, C A G; Cunha, F M

2014-05-01

112

Learning from the Piper Alpha accident: A postmortem analysis of technical and organizational factors  

SciTech Connect

The accident that occurred on board the offshore platform Piper Alpha in July 1988 killed 167 people and cost billions of dollars in property damage. It was caused by a massive fire, which was not the result of an unpredictable act of God' but of an accumulation of errors and questionable decisions. Most of them were rooted in the organization, its structure, procedures, and culture. This paper analyzes the accident scenario using the risk analysis framework, determines which human decision and actions influenced the occurrence of the basic events, and then identifies the organizational roots of these decisions and actions. These organizational factors are generalizable to other industries and engineering systems. They include flaws in the design guidelines and design practices (e.g., tight physical couplings or insufficient redundancies), misguided priorities in the management of the tradeoff between productivity and safety, mistakes in the management of the personnel on board, and errors of judgement in the process by which financial pressures are applied on the production sector (i.e., the oil companies' definition of profit centers) resulting in deficiencies in inspection and maintenance operations. This analytical approach allows identification of risk management measures that go beyond the purely technical (e.g., add redundancies to a safety system) and also include improvements of management practices. 18 refs., 4 figs.

Pate-Cornell, M.E. (Stanford Univ., CA (United States))

1993-04-01

113

Aedes aegypti larvicide from the ethanolic extract of Piper nigrum black peppercorns.  

PubMed

Due to unavailability of a vaccine and a specific cure to dengue, the focus nowadays is to develop an effective vector control method against the female Aedes aegypti mosquito. This study aims to determine the larvicidal fractions from Piper nigrum ethanolic extracts (PnPcmE) and to elucidate the identity of the bioactive compounds that comprise these larvicidal fractions. Larvicidal assay was performed by subjecting 3rd to 4th A. aegypti instar larvae to PnPcmE of P. nigrum. The PnPcmE exhibited potential larvicidal activity having an LC50 of 7.1246 ± 0.1304 ppm (mean ± Std error). Normal phase vacuum liquid chromatography of the PnPcmE was employed which resulted in five fractions, two of which showed larvicidal activity. The most active of the PnPcmE fractions is PnPcmE-1A, with an LC50 and LC90 of 1.7101 ± 0.0491 ppm and 3.7078 ppm, respectively. Subsequent purification of PnPcmE-1A allowed the identification of the larvicidal compound as oleic acid. PMID:25118563

Santiago, Viviene S; Alvero, Rita Grace; Villaseñor, Irene M

2015-03-01

114

The antioxidant activity of allylpyrocatechol is mediated via decreased generation of free radicals along with escalation of antioxidant mechanisms.  

PubMed

Allylpyrocatechol (APC) is responsible for the antiinflammatory activity exhibited by the methanolic extract of leaves of Piper betle. As antiinflammatory compounds may display antioxidant properties and vice versa, we investigated the antioxidant effect of APC. APC effectively reduced phorbol-myristate-acetate-induced generation of reactive oxygen species and superoxide in murine peritoneal macrophages as well as inhibited Escherichia-coli-induced phagocytic activity of macrophages. Furthermore, pBluescript SK(+) plasmid DNA damage induced by addition of sodium ascorbate was attenuated by APC as it inhibited transformation of the supercoiled form to a relaxed form. In addition, APC increased the enzymatic (catalase) and nonenzymatic (GSH) antioxidant components of murine macrophages. Taken together, APC exhibited an antioxidant activity which was mediated both via decreased generation of free radicals along with increase in cellular antioxidants. PMID:22585425

Sarkar, Debjani; Kundu, Sunanda; De, Soumita; Hariharan, Chellaram; Saha, Piu; Manna, Alak; Chattopadhyay, Subrata; Chatterjee, Mitali

2013-03-01

115

Lateral gas diffusion inside leaves.  

PubMed

Diffusion of CO2 inside leaves is generally regarded to be from the substomatal cavities to the assimilating tissues, i.e. in the vertical direction of the leaf blades. However, lateral gas diffusion within intercellular air spaces may be much more effective than hitherto considered. In a previous work it was demonstrated that, when 'clamp-on' leaf chambers are used, leaf internal 'CO2 leakage' beyond the leaf chamber gaskets may seriously affect gas exchange measurement. This effect has been used in the present paper to quantify gas conductance (g(leaf,l), mmol m(-2) s(-1)) in the lateral directions within leaves and significant differences between homo- and heterobaric leaves were observed. For the homobaric leaves, lateral gas conductance measured over a distance of 6 or 8 mm (the widths of the chamber gaskets) was 2-20% of vertical conductance taken from published data measured over much smaller distances of 108-280 microm (the thickness of the leaves). The specific internal gas diffusion properties of the leaves have been characterized by gas conductivities (g*(leaf), micromol m(-1) s(-1)). Gas conductivities in the lateral directions of heterobaric leaves were found to be small but not zero. In homobaric leaves, they were between 67 and 209 micromol m(-1) s(-1) and thus even larger than those in the vertical direction of the leaf blades (between 15 and 78 micromol m(-1) s(-1)). The potential implications for experimentalists performing gas exchange measurements are discussed. PMID:15668225

Pieruschka, Roland; Schurr, Ulrich; Jahnke, Siegfried

2005-03-01

116

Oranges - Flowers, Leaves, and Fruit  

USGS Multimedia Gallery

Five orange blossoms against a backdrop of citrus leaves and a mature orange produced by the previous year's blossoms. One blossom has already been pollinated and has lost its surrounding petals leaving the pistil isolated. Photograph taken March 15-16, 2008....

117

See the Colors in Leaves  

NSDL National Science Digital Library

Learners use chromatography to separate and analyze the mixture of pigments in leaves. Use this activity to discuss photosynthesis as well as why leaves change color in autumn. Safety note: Nail polish remover is flammable; do not use near heat. It also is harmful if ingested. Adult supervision recommended.

2012-03-22

118

Methyl 4-hydroxy-3-(3'-methyl-2'-butenyl)benzoate, major insecticidal principle from Piper guanacastensis.  

PubMed

The CHCl3-soluble extract of Piper guanacastensis (Piperaceae) was found to have noteworthy insecticidal activity to Aedes atropalpus mosquito larvae (LC50 80.5 micrograms/mL). Bioassay-guided fractionation afforded methyl 4-hydroxy-3-(3'-methyl-2'-butenyl)benzoate (1) as the major bioactive constituent (LC50 20.5 micrograms/mL). The separation of compound 1 from its transesterification artifact (2), ethyl 4-hydroxy-3-(3'-methyl-2'-butenyl)benzoate, was achieved by recycling reversed-phase HPLC. The flavonoids acacetin, chrysin, and pinostrobin were also isolated from the active fraction but did not display insecticidal properties. PMID:9090871

Pereda-Miranda, R; Bernard, C B; Durst, T; Arnason, J T; Sánchez-Vindas, P; Poveda, L; San Román, L

1997-03-01

119

Family & Medical Leave A Guide for Supervisors  

E-print Network

Family & Medical Leave A Guide for Supervisors As a supervisor, it is important for you to know how & Medical Leave Act (FMLA) &/or Wisconsin Family & Medical Leave Act (WFMLA) and to know what to do with confidential medical information. FMLA and WFMLA are leave entitlements for reasonable, job-protected leave

Saffman, Mark

120

Antidiabetic and antihyperlipidemic activity of Piper longum root aqueous extract in STZ induced diabetic rats  

PubMed Central

Background The available drugs for diabetes, Insulin or Oral hypoglycemic agents have one or more side effects. Search for new antidiabetic drugs with minimal or no side effects from medicinal plants is a challenge according to WHO recommendations. In this aspect, the present study was undertaken to evaluate the antihyperglycemic and antihyperlipidemic effects of Piper longum root aqueous extract (PlrAqe) in streptozotocin (STZ) induced diabetic rats. Methods Diabetes was induced in male Wister albino rats by intraperitoneal administration of STZ (50 mg/kg.b.w). Fasting blood glucose (FBG) levels were measured by glucose-oxidase & peroxidase reactive strips. Serum biochemical parameters such as glycosylated hemoglobin (HbA1c), total cholesterol (TC), triglycerides (TG), very low density lipoprotein (VLDL), low density lipoprotein (LDL) and high density lipoprotein (HDL) cholesterol were estimated. The activities of liver and kidney functional markers were measured. The statistical analysis of results was carried out using Student t-test and one-way analysis (ANOVA) followed by DMRT. Results During the short term study the aqueous extract at a dosage of 200 mg/kg.b.w was found to possess significant antidiabetic activity after 6 h of the treatment. The administration of aqueous extract at the same dose for 30 days in STZ induced diabetic rats resulted in a significant decrease in FBG levels with the corrections of diabetic dyslipidemia compared to untreated diabetic rats. There was a significant decrease in the activities of liver and renal functional markers in diabetic treated rats compared to untreated diabetic rats indicating the protective role of the aqueous extract against liver and kidney damage and its non-toxic property. Conclusions From the above results it is concluded that the plant extract is capable of managing hyperglycemia and complications of diabetes in STZ induced diabetic rats. Hence this plant may be considered as one of the potential sources for the isolation of new oral anti hypoglycemic agent(s). PMID:23414307

2013-01-01

121

Effect of reverse photoperiod on in vitro regeneration and piperine production in Piper nigrum L.  

PubMed

In this study, a novel approach for in vitro regeneration of Piper nigrum L. has been applied in order to increase healthy biomass, phytochemicals and piperine production via reverse photoperiod (16hD/8hL). Leaf portions of the seed-derived plants were placed on an MS-medium fortified with different PGRs. Under 16hD/8hL, thidiazuron (TDZ; 4.0 mg L?¹) and BA (1.5 mg L?¹) was found to be the most effective (<90%) in callus induction. Two concentrations (1.5, 2.0 mg L?¹) of the IBA produced>80% shoots from callus cultures. Healthy shoots were transferred to rooting medium and higher percentage of rooting (<90%) was observed on IBA (1.5 mg L?¹). These in vitro tissues were subjected to amino acid analysis, spectrophotometry, and HPLC. ARG, SER, THR, and TYR were the most abundant components out of 17 amino acids. Higher amino acid production was observed under normal photoperiod (16hL/8hD) than under reverse photoperiod (16hD/8hL). The highest total phenolic content (TPC; 9.91 mg/g-DW) and flavonoid content (7.38 mg/g-DW) were observed in callus cultures incubated under 16hL/8hD than other tissues incubated under 16hD/8hL photoperiod. Higher DPPH and PoMo activities were observed in tissues incubated under 16hL/8hD photoperiod, while ABTS and Fe²? chelating activities were found higher in tissues incubated under reverse photoperiod. Significant quantities of piperine content were observed in all tissues except callus cultures. These results suggest that reverse photoperiod is a promising approach for callus induction, phytochemicals and piperine production for commercial applications. PMID:24439548

Ahmad, Nisar; Abbasi, Bilal Haider; Fazal, Hina; Khan, Mubarak Ali; Afridi, Muhammad Siddique

2014-01-01

122

A novel nerolidol-rich essential oil from Piper claussenianum modulates Candida albicans biofilm.  

PubMed

Candidiasis is a major opportunistic fungal infection in humans, and its incidence has increased steadily over the last two decades. Candida albicans, the main species of the genus, has a large arsenal of virulence attributes that contribute to successful infections, such as dimorphism and biofilm formation. The adverse effects of eukaryotic antimicrobial therapies associated with an increase in resistance to the compounds presently available have boosted efforts to improve the therapeutic arsenal against candidiasis with a newer and cheaper range of drugs. In this study, a novel nerolidol-rich essential oil (EO) derived from Piper claussenianum (Miq.) C. DC., Piperaceae, was tested on the growth, transition (yeast to hyphae), formation and stability of biofilms produced by C. albicans. Both inflorescence and leaf EOs were evaluated and revealed MIC values ranging from 0.04 to 0.1?% and 0.2 to 1.26?%, respectively. Furthermore, leaf EO managed to downregulate the yeast-to-hyphae transition by 81?%, as well as reducing biofilm formation by about 30 and 50?% after incubation for 24 and 48 h, respectively. The EO was also able to reduce the viability of pre-formed biofilm by 63.9?%. Finally, the association between the leaf EO and fluconazole was evaluated and revealed an interesting synergistic effect. Taken together, these results demonstrate that this novel compound could be a promising agent and could reinforce the arsenal of therapeutic alternatives for the treatment of candidiasis. Furthermore, it may represent a novel and natural source of nerolidol, which could be of interest pharmaceutically. PMID:24523158

Curvelo, J A R; Marques, A M; Barreto, A L S; Romanos, M T V; Portela, M B; Kaplan, M A C; Soares, R M A

2014-05-01

123

Key Obama officials leave administration  

NASA Astrophysics Data System (ADS)

Secretary of the Interior Ken Salazar is one of the latest members of the Obama administration to announce that he is leaving his position near the start of President Obama's second term in office. Salazar, who has served as interior secretary since January 2009, intends to leave the department by the end of March, the department noted on 16 January. Salazar joins a number of other key officials who are planning to leave the administration. They include Environmental Protection Agency administrator Lisa Jackson, National Oceanic and Atmospheric Administration administrator Jane Lubchenco, and U.S. Geological Survey director Marcia McNutt.

Showstack, Randy

2013-01-01

124

Identification and simultaneous quantification of five alkaloids in Piper longum L. by HPLC-ESI-MS(n) and UFLC-ESI-MS/MS and their application to Piper nigrum L.  

PubMed

A simple, effective and suitable UFLC-ESI-MS/MS method was firstly developed to simultaneously determine five characteristic constituents (piperine, piperlonguminine, ??,?-dihydropiperlonguminine, pellitorine and piperanine) of Piper longum L. The total alkaloids of P. longum L. was prepared. The alkaloid contents of Piper nigrum L. and P. longum L. were compared. The analysis was carried out in multiple reaction monitoring scan mode. The method showed a good specificity, linearity (R(2)>0.995), stability (RSD<2.53%), repeatability (RSD<2.58%), and recovery (90.0-103.5%). The limits of detection and limits of quantification of five alkaloids were in the range of 0.02-0.03 and 0.05-0.10ng/mL, respectively. The intra- and inter-day precision was less than 9.30% and 9.55%, respectively. The validation results confirmed that the method could simultaneously determine the target alkaloids in the sample. Furthermore, the identities of the alkaloids were verified by HPLC-ESI-MS/MS. Compared with P. nigrum, P. longum had lower piperine content but was enriched in the other four alkaloids. PMID:25660876

Liu, Hao-Long; Luo, Rong; Chen, Xiao-Qing; Ba, Yin-Ying; Zheng, Li; Guo, Wei-Wei; Wu, Xia

2015-06-15

125

The thermal conductivity of leaves.  

PubMed

Thermal conductivities of fresh leaves, both unmodified and infiltrated with water, were measured. Samples were placed between silver plates of known and differing temperatures, and the time required to boil off a constant volume of liquid was measured. The species used are evergreens: Eucalyptus globulus Labill. (sclerophyllous) with isolateral leaf symmetry; and Peperomia obtusifolia A. Dietr. (succulent), Citrus limon Burm. f. (mesophyllous), Arbutus menziessii Pursh. (sclerophyllous), and Heteromeles arbutifolia M. Roem. (sclerophyllous), all with bilateral leaf symmetry. Mean values found were in the range of 0.268 to 0.573 W/m · °C for fresh leaves, and 0.540 to 0.548 W/m · °C for leaves infiltrated with water. An analysis of errors in the technique indicated that these values may be somewhat low. These results are several times higher than previously reported values. It is concluded that ordinary mesophytic and xerophytic leaves will not develop large gradients in temperature between the surfaces. PMID:24435441

Hays, R L

1975-01-01

126

5 CFR 630.1111 - Limitation on the amount of donated annual leave received by an emergency leave recipient.  

Code of Federal Regulations, 2010 CFR

...of donated annual leave received by an emergency leave recipient. 630.1111 Section...SERVICE REGULATIONS ABSENCE AND LEAVE Emergency Leave Transfer Program § 630.1111...of donated annual leave received by an emergency leave recipient. An emergency...

2010-01-01

127

Piper nigrum: micropropagation, antioxidative enzyme activities, and chromatographic fingerprint analysis for quality control.  

PubMed

A reliable in vitro regeneration system for the economical and medicinally important Piper nigrum L. has been established. Callus and shoot regeneration was encouraged from leaf portions on Murashige and Skoog (MS) medium augmented with varied concentrations of plant growth regulators. A higher callus production (90 %) was observed in explants incubated on MS medium incorporated with 1.0 mg L(-1) 6-benzyladenine (BA) along with 0.5 mg L(-1) gibberellic acid after 4 weeks of culture. Moreover, a callogenic response of 85 % was also recorded for 1.0 mg L(-1) BA in combination with 0.25 mg L(-1) ?-naphthalene acetic acid (NAA) and 0.25 mg L(-1) 2,4-dichlorophenoxyacetic acid or 0.5 mg L(-1) indole butyric acid (IBA) along with 0.25 mg L(-1) NAA and indole acetic acid. Subsequent sub-culturing of callus after 4 weeks of culture onto MS medium supplemented with 1.5 mg L(-1) thiodiazoran or 1.5 mg L(-1) IBA induced 100 % shoot response. Rooted plantlets were achieved on medium containing varied concentrations of auxins. The antioxidative enzyme activities [superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX)] revealed that significantly higher SOD was observed in regenerated plantlets than in other tissues. However, POD, CAT, and APX were higher in callus than in other tissues. A high-performance liquid chromatography (HPLC) fingerprint analysis protocol was established for quality control in different in vitro-regenerated tissues of P. nigrum L. During analysis, most of the common peaks represent the active principle "piperine." The chemical contents, especially piperine, showed variation from callus culture to whole plantlet regeneration. Based on the deviation in chromatographic peaks, the in vitro-regenerated plantlets exhibit a nearly similar piperine profile to acclimated plantlets. The in vitro regeneration system and HPLC fingerprint analysis established here brought a novel approach to the quality control of in vitro plantlets, producing metabolites of interest with substantial applications for the conservation of germplasm. PMID:23354497

Ahmad, Nisar; Abbasi, Bilal Haider; Rahman, Inayat ur; Fazal, Hina

2013-04-01

128

Invasive competitor and native seed predators contribute to rarity of the narrow endemic Astragalus sinuatus Piper.  

PubMed

The conservation of rare plant species hinges on our ability to identify the underlying mechanisms that limit rare plant populations. Theory on rarity suggests that both predispersal seed predation and competition can be important mechanisms influencing abundance and/or distribution of rare plant populations. Yet few studies have tested these interactions, and those that have evaluated each mechanism independently. Astragalus sinuatus Piper (Whited's milkvetch) is a narrow endemic plant species restricted to eight populations within a 10-km2 area in eastern Washington. We used experimental and observational methods to test the effects of native insect predispersal seed predators and an invasive grass (Bromus tectorum L. [cheatgrass]) on seed set and population density of A. sinuatus. We quantified per capita seed production and pod predation rates across four sites and among four years. Seed predation rates were high across four sites (66-82%) and all years (65-82%). Experimental reduction of predispersal seed predators significantly increased per capita seed set of A. sinuatus (164-345%) at two experimental sites. Concurrently, two seed addition experiments demonstrated the effect of seed loss and presence of B. tectorum on seedling recruitment and establishment of A. sinuatus over four growing seasons. In the first seed addition experiment, we found no difference in recruitment and establishment between low (40) and high (120) seed addition levels. In the second addition experiment (one level of addition; 40 seeds), we found that recruitment and survivorship increased 200% in plots where B. tectorum was removed compared to plots where B. tectorum was present. Thus, seed addition had no impact in the presence of B. tectorum; conversely, in the absence of B. tectorum, seed addition was highly effective at increasing population numbers. Results suggest that, in areas where B. tectorum is present, recruitment is site limited, and it is seed limited when B. tectorum is absent. We recommend that managers reduce B. tectorum in an effort to increase population growth of A. sinuatus; in areas where B. tectorum is absent, short-term reduction of insect predators should be considered as a strategy to increase population growth of this rare species. PMID:22073639

Combs, Julie K; Reichard, Sarah H; Groom, Martha J; Wilderman, David L; Camp, Pamela A

2011-10-01

129

Buying Additional Leave 1 Revised June 2009  

E-print Network

Buying Additional Leave 1 Revised June 2009 BUYING ADDITIONAL ANNUAL LEAVE 1.0 Introduction 1 outlines the option and process for buying additional annual leave which builds on existing provision to employees. 1.2 The payment arrangements for buying additional annual leave are outlined in 4.0 below

Davies, Christopher

130

Essential and toxic elements in three Pakistan's medicinal fruits (Punica granatum, Ziziphus jujuba and Piper cubeba) analysed by INAA.  

PubMed

Three important medicinal fruits generally used by the people of Pakistan for the treatment of different diseases have been studied for their mineral contents. Twenty-two major and minor trace elements (essential, toxic and non-essential) were identified in Punica granatum (pomegranate), Ziziphus jujuba (jujube) and Piper cubeba L. (cubeb) by employing instrumental neutron activation analysis technique. The studied medicinal herbs are a good source of the essential elements while toxic elements are found in trace amounts. K is detected as a major element in pomegranate, jujube and cubeb with respective values of 1.20%, 1.18% and 2.01%. Pomegranate has significant concentrations of Na, Zn, Cr and Se; jujube has high Cl, Zn, Mn and Co contents while cubeb is a good source of K and Fe. The baseline data presented in this work can be used in understanding the role of mineral elements in nutritive, preventive and therapeutic properties of medicinal herbs. PMID:22017565

Fatima, Ismat; Waheed, Shahida; Zaidi, Jamshed Hussain

2012-05-01

131

Compound Specific Extraction of Camptothecin from Nothapodytes nimmoniana and Piperine from Piper nigrum Using Accelerated Solvent Extractor.  

PubMed

Effects of varying temperatures with constant pressure of solvent on extraction efficiency of two chemically different alkaloids were studied. Camptothecin (CPT) from stem of Nothapodytes nimmoniana (Grah.) Mabb. and piperine from the fruits of Piper nigrum L. were extracted using Accelerated Solvent Extractor (ASE). Three cycles of extraction for a particular sample cell at a given temperature assured complete extraction. CPT and piperine were determined and quantified by using a simple and efficient UFLC-PDA (245 and 343?nm) method. Temperature increased efficiency of extraction to yield higher amount of CPT, whereas temperature had diminutive effect on yield of piperine. Maximum yield for CPT was achieved at 80°C and for piperine at 40°C. Thus, the study determines compound specific extraction of CPT from N. nimmoniana and piperine from P. nigrum using ASE method. The present study indicates the use of this method for simple, fast, and accurate extraction of the compound of interest. PMID:24527258

Upadhya, Vinayak; Pai, Sandeep R; Sharma, Ajay K; Hegde, Harsha V; Kholkute, Sanjiva D; Joshi, Rajesh K

2014-01-01

132

LC-MS/MS based identification of piperine production by endophytic Mycosphaerella sp. PF13 from Piper nigrum.  

PubMed

Piper nigrum is very remarkable for its medicinal properties due to the presence of metabolites like piperine. Emerging understanding on the biosynthetic potential of endophytic fungi suggests the possibility to have piperine producing fungi in P. nigrum. In the current study, endophytic fungi isolated from P. nigrum were screened for the presence of piperine by liquid chromatography-tandem mass spectrometry (LC-MS/MS). This resulted in the identification of a Mycosphaerella sp. with the ability to produce piperine extracellularly. The biosynthesis of piperine (C17H19NO3) by the endophytic fungal isolate was confirmed by the presence of m/z 286.1 (M + H(+)) in the LC-MS/MS analysis using positive mode ionization. This was further supported by the presence of specific fragment ions with masses 135, 143, 171 and 201 formed due to the fragmentation of piperine present in the fungal extract. PMID:24691878

Chithra, S; Jasim, B; Anisha, C; Mathew, Jyothis; Radhakrishnan, E K

2014-05-01

133

Planned Giving: Leaving a Legacy  

ERIC Educational Resources Information Center

It is a wonderful surprise when an executor calls to inform that one's college has been remembered in an individual's estate, either for a future gift or one that is being distributed. Leaving this legacy often enriches the final years of a donor's life. But too often, these opportunities are left to chance because community college development…

Edwards, Joan

2010-01-01

134

Leaves: Elevated CO2 levels  

Technology Transfer Automated Retrieval System (TEKTRAN)

Burning fossil fuels and land use changes such as deforestation and urbanization have led to a dramatic rise in the concentration of carbon dioxide (CO2) in the atmosphere since the onset of the Industrial Revolution. The highly dilute CO2 from the atmosphere enters plant leaves where it is concentr...

135

GRADUATE COLLEGE LEAVE OF ABSENCE  

E-print Network

on maintaining visa eligibility for reentering the United States. RETURNING FROM A LEAVE OF ABSENCE Upon their admitted student status; however, they are not registered and therefore do not have the rights any GI Bill education benefits, you must contact the Office of Veteran Services Other (please

Cho, Hokwon

136

Exoproteome and Secretome Derived Broad Spectrum Novel Drug and Vaccine Candidates in Vibrio cholerae Targeted by Piper betel Derived Compounds  

PubMed Central

Vibrio cholerae is the causal organism of the cholera epidemic, which is mostly prevalent in developing and underdeveloped countries. However, incidences of cholera in developed countries are also alarming. Because of the emergence of new drug-resistant strains, even though several generic drugs and vaccines have been developed over time, Vibrio infections remain a global health problem that appeals for the development of novel drugs and vaccines against the pathogen. Here, applying comparative proteomic and reverse vaccinology approaches to the exoproteome and secretome of the pathogen, we have identified three candidate targets (ompU, uppP and yajC) for most of the pathogenic Vibrio strains. Two targets (uppP and yajC) are novel to Vibrio, and two targets (uppP and ompU) can be used to develop both drugs and vaccines (dual targets) against broad spectrum Vibrio serotypes. Using our novel computational approach, we have identified three peptide vaccine candidates that have high potential to induce both B- and T-cell-mediated immune responses from our identified two dual targets. These two targets were modeled and subjected to virtual screening against natural compounds derived from Piper betel. Seven compounds were identified first time from Piper betel to be highly effective to render the function of these targets to identify them as emerging potential drugs against Vibrio. Our preliminary validation suggests that these identified peptide vaccines and betel compounds are highly effective against Vibrio cholerae. Currently we are exhaustively validating these targets, candidate peptide vaccines, and betel derived lead compounds against a number of Vibrio species. PMID:23382822

Barh, Debmalya; Barve, Neha; Gupta, Krishnakant; Chandra, Sudha; Jain, Neha; Tiwari, Sandeep; Leon-Sicairos, Nidia; Canizalez-Roman, Adrian; Rodrigues dos Santos, Anderson; Hassan, Syed Shah; Almeida, Síntia; Thiago Jucá Ramos, Rommel; Augusto Carvalho de Abreu, Vinicius; Ribeiro Carneiro, Adriana; de Castro Soares, Siomar; Luiz de Paula Castro, Thiago; Miyoshi, Anderson; Silva, Artur; Kumar, Anil; Narayan Misra, Amarendra; Blum, Kenneth; Braverman, Eric R.; Azevedo, Vasco

2013-01-01

137

Carnivorous leaves from Baltic amber.  

PubMed

The fossil record of carnivorous plants is very scarce and macrofossil evidence has been restricted to seeds of the extant aquatic genus Aldrovanda of the Droseraceae family. No case of carnivorous plant traps has so far been reported from the fossil record. Here, we present two angiosperm leaves enclosed in a piece of Eocene Baltic amber that share relevant morphological features with extant Roridulaceae, a carnivorous plant family that is today endemic to the Cape flora of South Africa. Modern Roridula species are unique among carnivorous plants as they digest prey in a complex mutualistic association in which the prey-derived nutrient uptake depends on heteropteran insects. As in extant Roridula, the fossil leaves possess two types of plant trichomes, including unicellular hairs and five size classes of multicellular stalked glands (or tentacles) with an apical pore. The apices of the narrow and perfectly tapered fossil leaves end in a single tentacle, as in both modern Roridula species. The glandular hairs of the fossils are restricted to the leaf margins and to the abaxial lamina, as in extant Roridula gorgonias. Our discovery supports current molecular age estimates for Roridulaceae and suggests a wide Eocene distribution of roridulid plants. PMID:25453067

Sadowski, Eva-Maria; Seyfullah, Leyla J; Sadowski, Friederike; Fleischmann, Andreas; Behling, Hermann; Schmidt, Alexander R

2015-01-01

138

Stanford Community Leave Bank Program Guidelines  

E-print Network

Stanford Community Leave Bank Program Guidelines h t t p : / / u h r . s t a n f o r d . e d u A Community Leave Bank Program Guidelines ­ July 1, 2012 Page 2 h t t p : / / u h r . s t a n f o r d . e d u their unused balance to a central leave bank fund. This central leave bank fund will be made available

Straight, Aaron

139

Gas transfer in floating-leaved plants  

Microsoft Academic Search

Pressurized gas transport with flow rates of 1.1 to 1.81 gas h-1 plant-1 have been detected in the floating-leaved aquatic macrophyte Euryale ferox on sunny days. The younger leaves gave the highest pressurization, but the gas flow was initiated mainly by the middle-aged leaves of the plants. The gas through-flow was shown to be highly beneficial for floating-leaved plants. It

W. Große; C. Bauch

1991-01-01

140

The New Jersey Family Leave Act  

E-print Network

The New Jersey Family Leave Act The New Jersey Family Leave Act (N.J.S.A. 34:11B-1, et seq.NJCivilRights.gov The New Jersey mily Leave Act w Jersey Family Leave Act (N.J.S.A. 34:11B-1, et seq.) requires. Pennsylvania Avenue, 3 rd Floor Atlantic City, NJ 08401 (609) 441-3100 (Phone) (609) 441-7648 (TTY) Jersey City

Liu, Alice Y.C.

141

Pregnancy, Teaching, and Leaving before Year's End.  

ERIC Educational Resources Information Center

This essay highlights one pregnant middle school teacher's experiences with taking a mid-year leave. She used entries from her personal diary to reflect on how she felt about her leave, while her students wrote letters and notes expressing their anxieties about her leaving. The discussion of planning a pregnancy and the stages of pregnancy, along…

Abdulrashid, Jamila

142

A unified explanation for anthocyanins in leaves?  

Microsoft Academic Search

The leaves from many of New Zealand's native species are remarkably polymorphic for anthocyanin expression. Red coloration varies not only as a function of seasonal and developmental factors, but can also differ among individuals of a population, among leaves within a canopy, and even among tissues within a leaf. Moreover, the biosynthesis of anthocyanin in these leaves can be induced

Kevin S. Gould; Sam O. Neill; Thomas C. Vogelmann

2002-01-01

143

A Postdoc's Guide to Paternity Leave  

NSDL National Science Digital Library

This guide provides general information on paternity leave for postdoc fathers following the birth of a child. It is intended as a companion guide to A Postdoc's Guide to Pregnancy and Maternity Leave. Adopting postdoc parents may want to consult our forthcoming companion guide on adoption leave.

Kathleen Flint Ehm (National Postdoctoral Association)

2012-06-01

144

Exploring Why Career Changers Leave Teaching  

ERIC Educational Resources Information Center

Survey data were used to explore the current teaching status and reasons for leaving or considering leaving teaching for 154 career changers who all graduated from a Master of Arts in Teaching (MAT) program over a 9-year time period. Respondents provided information about reasons for leaving teaching, indicating personal/family, career, and school…

Cuddapah, Jennifer L.; Beaty-O'Ferrall, Mary Ellen; Masci, Frank J.; Hetrick, Monica

2011-01-01

145

Leaving Home: Crisis and Opportunity  

PubMed Central

“Gaudeamus igitur, juvenes dum sumus!” Young people have not quite completed the developmental tasks of adolescence by the time they leave home to attend university. Geographical separation from family offers an opportunity for learning and personal growth, with the ultimate objective the acquisition of an education in the broadest sense of the word. University life with its peer pressures and academic stresses offers its own challenges and rewards. Unless there is close co-operation between family doctors and student-health physicians, the medical care of young adults degenerates into crisis management with loss of all the benefits of continuity of care. PMID:21267231

McSherry, James

1986-01-01

146

Resource capture by single leaves  

SciTech Connect

Leaves show a variety of strategies for maximizing CO{sub 2} and light capture. These are more meaningfully explained if they are considered in the context of maximizing capture relative to the utilization of water, nutrients and carbohydrates reserves. There is considerable variation between crops in their efficiency of CO{sub 2} and light capture at the leaf level. Understanding of these mechanisms indicate some ways in which efficiency of resource capture could be level cannot be meaningfully considered without simultaneous understanding of implications at the canopy level. 36 refs., 5 figs., 1 tab.

Long, S.P.

1992-05-01

147

Phytic acid in green leaves.  

PubMed

Phytic acid or phytate, the free-acid form of myo-inositolhexakiphosphate, is abundant in many seeds and fruits, where it represents the major storage form of phosphorus. Although also known from other plant tissues, available reports on the occurrence of phytic acid, e.g. in leaves, have never been compiled, nor have they been critically reviewed. We found 45 published studies with information on phytic acid content in leaves. Phytic acid was almost always detected when studies specifically tried to detect it, and accounted for up to 98% of total P. However, we argue that such extreme values, which rival findings from storage organs, are dubious and probably result from measurement errors. Excluding these high values from further quantitative analysis, foliar phytic acid-P averaged 2.3 mg·g(-1) , and represented, on average, 7.6% of total P. Remarkably, the ratio of phytic acid-P to total P did not increase with total P, we even detected a negative correlation of the two variables within one species, Manihot esculenta. This enigmatic finding warrants further attention. PMID:24341824

Hadi Alkarawi, H; Zotz, G

2014-07-01

148

Accelerated Stability and Chemical Kinetics of Ethanol Extracts of Fruit of Piper sarmentosum Using High Performance Liquid Chromatography  

PubMed Central

The extracts of Piper sarmentosum, a medicinal plant, are being used to prepare phytopharmaceuticals while the information about chemical kinetics of constituents of the extract is unavailable to assign precise shelf life (t90) and find optimum storage conditions of the product for patient safety, and to avoid economic repercussions of launching an unstable product. The extract was exposed to three different conditions of high temperature and relative humidity (RH) for six months. The samples were then analyzed at 0, 1, 2, 4 and 6 months by high performance liquid chromatography (HPLC) using pellitorine, sarmentine and sarmentosine as markers. Different chemical kinetic parameters of the markers were evaluated by Arrhenius equation to predict shelf life (t90) at different storage conditions and at room temperature. The markers in the extract followed the zero order degradation, and the activation energy, pre exponential factor and rate constant of the reaction of the markers were found to be varying in samples stored at different conditions. The contents of the markers were found to be decreasing at high temperature and humidity with the passage of time. The predicted shelf life (t90) of the markers at room temperature was found to be 16 months approximately. Results of this study indicate that extracts of the plant are stable at room temperature for 16 months. Moreover, the chemical kinetic data of the markers and the analytical method used to quantify the markers may be useful for phytopharmaceutical industry to produce efficacious and stable products from extracts of the plant. PMID:24250372

Khalid, Hussain; Zhari, Ismail; Amirin, Sadikun; Pazilah, Ibrahim

2011-01-01

149

Autumn leaves seen through herbivore eyes  

PubMed Central

Why leaves of some trees turn red in autumn has puzzled biologists for decades, as just before leaf fall the pigments causing red coloration are newly synthesized. One idea to explain this apparently untimely investment is that red colour signals the tree's quality to herbivorous insects, particularly aphids. However, it is unclear whether red leaves are indeed less attractive to aphids than green leaves. Because aphids lack a red photoreceptor, it was conjectured that red leaves could even be indiscernable from green ones for these insects. Here we show, however, that the colour of autumnal tree leaves that appear red to humans are on average much less attractive to aphids than green leaves, whereas yellow leaves are much more attractive. We conclude that, while active avoidance of red leaves by aphids is unlikely, red coloration in autumn could still be a signal of the tree's quality, or alternatively serve to mask the over-attractive yellow that is unveiled when the green chlorophyll is recovered from senescing leaves. Our study shows that in sensory ecology, receiver physiology alone is not sufficient to reveal the whole picture. Instead, the combined analysis of behaviour and a large set of natural stimuli unexpectedly shows that animals lacking a red photoreceptor may be able to differentiate between red and green leaves. PMID:18782744

Döring, Thomas F; Archetti, Marco; Hardie, Jim

2008-01-01

150

Phenolics of Moringa oleifera leaves.  

PubMed

Five flavonol glycosides characterised as kaempferide 3-O-(2'',3''-diacetylglucoside), kaempferide 3-O-(2''-O-galloylrhamnoside), kaempferide 3-O-(2''-O-galloylrutinoside)-7-O-alpha-rhamnoside, kaempferol 3-O-[beta-glucosyl-(1 --> 2)]-[alpha-rhamnosyl-(1 --> 6)]-beta-glucoside-7-O-alpha-rhamnoside and kaempferol 3-O-[alpha-rhamnosyl-(1 --> 2)]-[alpha-rhamnosyl-(1 --> 4)]-beta-glucoside-7-O-alpha-rhamnoside together with benzoic acid 4-O-beta-glucoside, benzoic acid 4-O-alpha-rhamnosyl-(1 --> 2)-beta-glucoside and benzaldehyde 4-O-beta-glucoside have been isolated from methanolic extract of Moringa oleifera leaves. Also obtained from the same extract were known compounds, kaempferol 3-O-alpha-rhamnoside, kaempferol, syringic acid, gallic acid, rutin and quercetin 3-O-beta-glucoside. Their structures were determined using spectroscopic methods as well as comparison with data from known compounds. PMID:17365690

Manguro, Lawrence Onyango Arot; Lemmen, Peter

2007-01-01

151

Paternity leave experiences of NHS doctors.  

PubMed

This study assesses NHS doctors' experiences of paternity leave and evaluates whether practices have changed since the introduction of additional paternity leave (APL) in April 2011. An anonymised online survey designed to discover experiences and uptake of APL and ordinary paternity leave (OPL) was distributed to all members of the London Deanery Synapse® network. In total, 364 fathers responded. Their seniority ranged from foundation trainees to consultants. Following the formal introduction of OPL in 2003, the number of fathers taking any paternity leave increased (from 50% to 95.6%). The majority of respondents (76.7%) felt well supported by their employer. Since the introduction of APL, 3% of respondents took additional leave. Reasons for the low uptake of APL included the impracticalities of the law, poor awareness and perceived attitudes and implications for training. Problems with OPL included the inadequate provision of cover and difficulties in timing the leave appropriately. PMID:24115693

Gordon, Hannah; Szram, Joanna

2013-10-01

152

Production of high titre antibody response against Russell's viper venom in mice immunized with ethanolic extract of fruits of Piper longum L. (Piperaceae) and piperine.  

PubMed

Piper longum L. fruits have been traditionally used against snakebites in north-eastern and southern region of India. The aim of the study was to assess the production of antibody response against Russell's viper venom in mice after prophylactic immunization with ethanolic extract of fruits of Piper longum L. and piperine. The mice sera were tested for the presence of antibodies against Russell's viper venom by in vitro lethality neutralization assay and in vivo lethality neutralization assay. Polyvalent anti-snake venom serum (antivenom) manufactured by Haffkine Bio-Pharmaceutical Corporation Ltd. was used as standard. Further confirmation of presence of antibodies against the venom in sera of mice immunized with PLE and piperine was done using indirect enzyme-linked immunosorbent assay (ELISA) and double immunodiffusion test. Treatment with PLE-treated mice serum and piperine-treated mice serum was found to inhibit the lethal action of venom both in the in vitro lethality neutralization assay and in vivo lethality neutralization assay. ELISA testing indicated that there were significantly high (p<0.01) levels of cross reactions between the PLE and piperine treated mice serum and the venom antigens. In double immunodiffusion test, a white band was observed between the two wells of antigen and antibodies for both the PLE-treated and piperine-treated mice serum. Thus it can be concluded that immunization with ethanolic extract of fruits of Piper longum and piperine produced a high titre antibody response against Russell's viper venom in mice. The antibodies against PLE and piperine could be useful in antivenom therapy of Russell's viper bites. PLE and piperine may also have a potential interest in view of the development of antivenom formulations used as antidote against snake bites. PMID:24060214

Shenoy, P A; Nipate, S S; Sonpetkar, J M; Salvi, N C; Waghmare, A B; Chaudhari, P D

2014-01-15

153

5 CFR 630.1204 - Intermittent leave or reduced leave schedule.  

Code of Federal Regulations, 2011 CFR

...intermittently or on a reduced leave schedule when medically necessary, subject...intermittently or on a reduced leave schedule that is foreseeable based...authority; (2) The same type of appointment, work schedule, status, and tenure;...

2011-01-01

154

5 CFR 630.1204 - Intermittent leave or reduced leave schedule.  

Code of Federal Regulations, 2010 CFR

...intermittently or on a reduced leave schedule when medically necessary, subject...intermittently or on a reduced leave schedule that is foreseeable based...authority; (2) The same type of appointment, work schedule, status, and tenure;...

2010-01-01

155

Fed Leaves Interest Rates Alone  

NSDL National Science Digital Library

This week's In the News looks at the recent Federal Reserve Board decision to leave interest rates unchanged. The eight resources discussed provide background information on interest rates and inflation, Federal Reserve news, and current US economic data. With the stock market at record highs and global economic crises fading, the Federal Reserve Board (FRB) showed increased concern about the risk of inflation this month at a May 18, 1999 meeting of the Federal Open Market Committee (FOMC). Although committee members ultimately decided not to raise the rate at which banks lend to each other, they cited a "tight" domestic labor market and "ongoing strength in demand in excess of productivity gains" as possible reasons for future rate hikes. Wall Street reacted to the Fed news with a 100 point Dow Jones Industrial Average fall on May 18 but recovered by the end of the day down just 16.52, and many market watchers expressed optimism over the FOMC action. Irwin Kellner, chief economist at CBS.MarketWatch.com, for example, deemed the decision "great" and praised the Fed for a flexible policy that is not locked into a particular course of action should the economy change unexpectedly.

Waters, Megan.

156

MEDICAL LEAVE/CRISIS RESPONSE POLICIES Mandated Medical Leave of Absence for Physiological Reasons Policy  

E-print Network

MEDICAL LEAVE/CRISIS RESPONSE POLICIES Mandated Medical Leave of Absence for Physiological Reasons Policy A student will be placed on mandatory medical leave if the following has occurred: · It has been determined by a Health Service clinician (NP or MD) that the student requires more intensive medical care

157

Plants: Roots, Stems and Leaves 85 Plants: Roots, Stems and Leaves  

E-print Network

are at the tips (or apices) of plant parts. The shoot apical meristem is at the tip of the shoot, while the root;Plants: Roots, Stems and Leaves 87 The basic parts of the leaf are a leaf base, which is the region wherePlants: Roots, Stems and Leaves 85 Plants: Roots, Stems and Leaves Unlike animals, plants only have

Koptur, Suzanne

158

Why Leaves Turn Red in Autumn. The Role of Anthocyanins in Senescing Leaves of  

E-print Network

Why Leaves Turn Red in Autumn. The Role of Anthocyanins in Senescing Leaves of Red-Osier Dogwood1 the leaves of many woody species accumulate anthocyanins prior to being shed has long puzzled biologists because it is unclear what effects anthocyanins may have on leaf function. Here, we provide evidence

Holbrook, N. Michele

159

Resilience and Young People Leaving Care  

ERIC Educational Resources Information Center

How do we promote the resilience of young people leaving care? This article explores this question by bringing together research findings on the resilience of young people from disadvantaged family backgrounds with research studies on young people leaving care. These findings are applied to young people during their journey to adulthood: their…

Stein, Mike

2008-01-01

160

Manager's Guide for Family Leave Transitions  

E-print Network

Cambridge, MA 02138 Crimson Cares including Manager's Guide for Family Leave Transitions 3 #12;GoodManager's Guide for Family Leave Transitions When a member of your team is prepar- ing to go will increase the likelihood of a smooth transition and ap- propriate coverage of job responsibilities. Helping

Wolfe, Patrick J.

161

20 CFR 638.532 - Annual leave.  

Code of Federal Regulations, 2010 CFR

...annual leave at any time subject to approval...allowed only after the student has spent 180 days in pay status in Job Corps, and only once...enrollment. (e) Students shall not be charged annual leave for travel time to and from home...

2010-04-01

162

A versatile scattering model for deciduous leaves  

Microsoft Academic Search

A versatile, multi-frequency scattering model is developed for deciduous leaves. The model gains its versatility from estimating the field inside the leaves, which are represented by elliptic discs, through employing a technique bridging the generalized Rayleigh-Gans (GRG) and the physical optics (PO) approximations. Analytic and numerical results are presented to illustrate the model versatility

Mostafa A. Karam; GenCorp Aerojet

1998-01-01

163

Extended Leaves of Absence for Classroom Teachers.  

ERIC Educational Resources Information Center

Extended leave of absence policies for classroom teachers in 129 school systems with enrollments of 25,000 or more are reported for 1965-66 in this national survey. A table lists, in order of descending frequency, the following purposes for which leaves are granted: (1) Military service, (2) professional study, (3) maternity, (4) exchange teaching…

Educational Research Service Circular, 1966

1966-01-01

164

Effect of different in vitro culture extracts of black pepper (Piper nigrum L.) on toxic metabolites-producing strains.  

PubMed

In the present study, the effect of different in vitro cultures (callus, in vitro shoots) and commercially available peppercorn extract was investigated for its activity against toxic metabolite-producing strains (Escherichia coli, Pseudomonas aeroginosa, Salmonella typhi, Bacillus subtilis, Bacillus cereus, Staphylococcus aureus, and Candida albicans). These in vitro cultures were extracted with ethanol, hexane, and chloroform, and the antipathogenic activity was determined by well-diffusion method. Hexane extract of callus showed 22 mm zone of inhibition against B. cereus, 23 mm against S. aureus, while regenerated shoots and seeds have shown 24.3 and 26 mm zones of inhibition. The ethanolic extracts of regenerated Piper shoots have shown 25 mm activity against S. aureus, 21 mm against B. cereus, and 16 mm in the case of C. albicans in comparison with standard antibiotics. Peppercorn extracts in chloroform and ethanol had shown activities against B. cereus (23.6 mm) and B. subtilis (23.5 mm). During in vitro organogenesis and morphogenesis, cells and tissues produced a comparable phytochemicals profile like mother plant. Morphogenesis is critically controlled by the application of exogenous plant-growth regulators. Such addition alters the hormonal transduction pathways, and cells under in vitro conditions regenerate tissues, which are dependant on the physiological state of cells, and finally enhance the production of secondary metabolites. To the best of our knowledge, this is the first report to compare the antimicrobial potential of in vitro regenerated tissues and peppercorn with standard antibiotics. In conclusion, most of the extracts showed pronounced activities against all the pathogenic microbes. This is a preliminary work, and the minimum inhibitory concentration values needs to be further explored. Regenerated tissues of P. nigrum are a good source of biologically active metabolites for antimicrobial activities, and callus culture presented itself as a good candidate for such activities. PMID:24193053

Ahmad, Nisar; Abbasi, Bilal Haider; Fazal, Hina

2013-11-01

165

Characteristics of photosynthesis in peach leaves.  

PubMed

Seasonal photosynthetic patterns of Loring peach (Prunus persica (L). Batsch) leaves were monitored throughout the 1974 growing season. Using leaves on detached branches, CO2 exchange was measured under controlled light and temperature conditions. Net photosynthesis rate varied from 9 to 12.4 mg CO2 dm(-2) leaf area h(-1) and was correlated with fruit development, with the highest values occurring during the final stage of fruit maturation. The proximity of fruits to leaves also regulated photosynthesis, with the highest rates occurring in leaves closest to fruit. Soluble-sugar content in fruits and fruit yield were highest in tree areas with greatest exposure to direct sunlight although leaf area was evenly distributed throughout the tree. Light and temperature optimum for photosynthesis in peach leaves was 9.5×10(-3) erg cm(-2) s(-1) and 30°, respectively. PMID:24430151

Crews, C E; Williams, S L; Vines, H M

1975-01-01

166

Changes in spectral properties of detached leaves  

NASA Technical Reports Server (NTRS)

If leaf senescence can be delayed for several days without significant changes in spectral properties, then samples of leaves at remote test sites could be prepared and shipped to laboratories to measure spectral properties. The changes in spectral properties of detached leaves were determined. Leaves from red birch and red pine were immersed in water or 0.001 M benzylaminopurine (BAP) and stored in plastic bags in the dark at either 5 or 25 C. Total directional-hemispherical reflectance and transmittance of the adaxial surface of birch leaves were measured over the 400 to 1100 nm wavelength region with a spectroradiometer and integrating sphere. Pine needles were taped together and reflectance of the mat of needles was measured. Spectral properties changed less than 5% of initial values during the first week when leaves were stored at 5 C. Storage at 25 C promoted rapid senescence and large changes in spectral properties. BAP delayed, but did not stop, senescence at 25 C.

Daughtry, C. S. T.; Biehl, L. L.

1984-01-01

167

Chemopreventive and Antilipidperoxidative Efficacy of Piper longum (Linn.) on 7,12-dimethylbenz (a) anthracene (DMBA) Induced Hamster Buccal Pouch Carcinogenesis  

NASA Astrophysics Data System (ADS)

Aim of the present study was to find out the chemopreventive efficacy of Piper longum, a plant having diverse medicinal properties, in 7,12-dimethyl benz (a) anthracene (DMBA) induced oral carcinogenesis. The mechanistic pathway for its chemopreventive potential was analysed by measuring lipid peroxidation and antioxidants status in DMBA induced oral cancer. DMBA painting in hamster buccal pouch three times per week for 14 weeks resulted in well developed, well differentiated squamous cell carcinoma. Elevated lipid peroxidation and decline in antioxidants were noticed in tumor bearing hamsters as compared to control animals. Oral administration of ethanolic extract of Piper longum dried fruits (PLEFet) on alternate days to DMBA painting significantly prevented the tumor incidence, volume and burden and restored the status of lipid peroxidation and antioxidants in DMBA painted hamsters. Our results indicate that the dried fruits of P. longum has suppressing effects on cell proliferation, which is probably due to its antilipid peroxidative and antioxidative potential during DMBA induced oral carcinogenesis.

Senthil, Namasivayam; Manoharan, Shanmugam; Balakrishnan, Subramanian; Rajmani Ramachandran, Cinnamanoor; Muralinaidu, Radhakrishnan

168

5 CFR 630.911 - Restoration of transferred annual leave.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Restoration of transferred annual leave. 630...Leave Transfer Program § 630.911 Restoration of transferred annual leave...leave donors who, on the date leave restoration is made, are employed by a...

2011-01-01

169

5 CFR 630.911 - Restoration of transferred annual leave.  

...2014-01-01 2014-01-01 false Restoration of transferred annual leave. 630...Leave Transfer Program § 630.911 Restoration of transferred annual leave...leave donors who, on the date leave restoration is made, are employed by a...

2014-01-01

170

5 CFR 630.911 - Restoration of transferred annual leave.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Restoration of transferred annual leave. 630...Leave Transfer Program § 630.911 Restoration of transferred annual leave...leave donors who, on the date leave restoration is made, are employed by a...

2013-01-01

171

5 CFR 630.911 - Restoration of transferred annual leave.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 2012-01-01 false Restoration of transferred annual leave. 630...Leave Transfer Program § 630.911 Restoration of transferred annual leave...leave donors who, on the date leave restoration is made, are employed by a...

2012-01-01

172

5 CFR 630.911 - Restoration of transferred annual leave.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Restoration of transferred annual leave. 630...Leave Transfer Program § 630.911 Restoration of transferred annual leave...leave donors who, on the date leave restoration is made, are employed by a...

2010-01-01

173

Complete chloroplast genome sequences of Drimys, Liriodendron, andPiper: Implications for the phylogeny of magnoliids and the evolution ofGC content  

SciTech Connect

The magnoliids represent the largest basal angiosperm clade with four orders, 19 families and 8,500 species. Although several recent angiosperm molecular phylogenies have supported the monophyly of magnoliids and suggested relationships among the orders, the limited number of genes examined resulted in only weak support, and these issues remain controversial. Furthermore, considerable incongruence has resulted in phylogenies supporting three different sets of relationships among magnoliids and the two large angiosperm clades, monocots and eudicots. This is one of the most important remaining issues concerning relationships among basal angiosperms. We sequenced the chloroplast genomes of three magnoliids, Drimys (Canellales), Liriodendron (Magnoliales), and Piper (Piperales), and used these data in combination with 32 other completed angiosperm chloroplast genomes to assess phylogenetic relationships among magnoliids. The Drimys and Piper chloroplast genomes are nearly identical in size at 160,606 and 160,624 bp, respectively. The genomes include a pair of inverted repeats of 26,649 bp (Drimys) and 27,039 (Piper), separated by a small single copy region of 18,621 (Drimys) and 18,878 (Piper) and a large single copy region of 88,685 bp (Drimys) and 87,666 bp (Piper). The gene order of both taxa is nearly identical to many other unrearranged angiosperm chloroplast genomes, including Calycanthus, the other published magnoliid genome. Comparisons of angiosperm chloroplast genomes indicate that GC content is not uniformly distributed across the genome. Overall GC content ranges from 34-39%, and coding regions have a substantially higher GC content than non-coding regions (both intergenic spacers and introns). Among protein-coding genes, GC content varies by codon position with 1st codon > 2nd codon > 3rd codon, and it varies by functional group with photosynthetic genes having the highest percentage and NADH genes the lowest. Across the genome, GC content is highest in the inverted repeat due to the presence of rRNA genes and lowest in the small single copy region where most NADH genes are located. Phylogenetic analyses using maximum parsimony and maximum likelihood methods were performed on DNA sequences of 61 protein-coding genes. Trees from both analyses provided strong support for the monophyly of magnoliids and two strongly supported groups were identified, the Canellales/Piperales and the Laurales/Magnoliales. The phylogenies also provided moderate to strong support for the basal position of Amborella, and a sister relationship of magnoliids to a clade that includes monocots and eudicots. The complete sequences of three magnoliid chloroplast genomes provide new data from the largest basal angiosperm clade. Evolutionary comparisons of these new genome sequences, combined with other published angiosperm genome, confirm that GC content is unevenly distributed across the genome by location, codon position, and functional group. Furthermore, phylogenetic analyses provide the strongest support so far for the hypothesis that the magnoliids are sister to a large clade that includes both monocots and eudicots.

Zhengqiu, C.; Penaflor, C.; Kuehl, J.V.; Leebens-Mack, J.; Carlson, J.; dePamphilis, C.W.; Boore, J.L.; Jansen, R.K.

2006-06-01

174

Plant Structure--Leaves, Stems, and Roots  

NSDL National Science Digital Library

Page one consists of a full color illustration of an idealized plant, showing various leaf, stem and root features. Page two illustrates various adaptations of plant flowers, leaves and stems. All illustrations are accompanied by explanations of the structures' functions.

2000-01-01

175

The Chromatography of Leaves and Inks.  

ERIC Educational Resources Information Center

Describes the use of a simple process known as chromatography to separate and observe the color pigments in leaves, inks, and other materials. Provides some historical background and detailed procedures. (DDR)

Chemecology, 1997

1997-01-01

176

Family and Medical Leave Act (FMLA)  

MedlinePLUS

... Medical Leave Act of 1993 (FMLA) in light of the United States Supreme Court’s decision in United States v. Windsor, which found section 3 of the Defense of Marriage Act (DOMA) to be unconstitutional. ...

177

Family Medical Leave Process No Yes  

E-print Network

Family Medical Leave Process applicable) or discusses other required supporting documentation. * Does employee meet the basic. No Yes *Contact your HR Consultant regarding the appropriate documentation. If the employee provides

New Mexico, University of

178

38 CFR 21.342 - Leave accounting policy.  

Code of Federal Regulations, 2010 CFR

...CONTINUED) VOCATIONAL REHABILITATION AND EDUCATION Vocational Rehabilitation and Employment Under 38 U.S.C. Chapter 31 Leaves of Absence § 21.342 Leave accounting policy. (a) Amount of leave. A veteran pursuing one of the...

2010-07-01

179

38 CFR 21.342 - Leave accounting policy.  

...CONTINUED) VOCATIONAL REHABILITATION AND EDUCATION Vocational Rehabilitation and Employment Under 38 U.S.C. Chapter 31 Leaves of Absence § 21.342 Leave accounting policy. (a) Amount of leave. A veteran pursuing one of the...

2014-07-01

180

38 CFR 21.342 - Leave accounting policy.  

Code of Federal Regulations, 2011 CFR

...CONTINUED) VOCATIONAL REHABILITATION AND EDUCATION Vocational Rehabilitation and Employment Under 38 U.S.C. Chapter 31 Leaves of Absence § 21.342 Leave accounting policy. (a) Amount of leave. A veteran pursuing one of the...

2011-07-01

181

38 CFR 21.342 - Leave accounting policy.  

Code of Federal Regulations, 2012 CFR

...CONTINUED) VOCATIONAL REHABILITATION AND EDUCATION Vocational Rehabilitation and Employment Under 38 U.S.C. Chapter 31 Leaves of Absence § 21.342 Leave accounting policy. (a) Amount of leave. A veteran pursuing one of the...

2012-07-01

182

38 CFR 21.6340 - Leaves of absence.  

Code of Federal Regulations, 2010 CFR

... 2 2010-07-01 2010-07-01 false Leaves of absence. 21.6340 Section 21.6340...Vocational Training for Certain New Pension Recipients Leaves of Absence § 21.6340 Leaves of absence. (a) General. VA may...

2010-07-01

183

38 CFR 21.342 - Leave accounting policy.  

Code of Federal Regulations, 2013 CFR

...CONTINUED) VOCATIONAL REHABILITATION AND EDUCATION Vocational Rehabilitation and Employment Under 38 U.S.C. Chapter 31 Leaves of Absence § 21.342 Leave accounting policy. (a) Amount of leave. A veteran pursuing one of the...

2013-07-01

184

38 CFR 21.6340 - Leaves of absence.  

Code of Federal Regulations, 2011 CFR

... 2 2011-07-01 2011-07-01 false Leaves of absence. 21.6340 Section 21.6340...Vocational Training for Certain New Pension Recipients Leaves of Absence § 21.6340 Leaves of absence. (a) General. VA may...

2011-07-01

185

Spanning directed trees with many leaves  

Microsoft Academic Search

The Directed Maximum Leaf Out-Branching problem is to flnd an out-branching (i.e. a rooted oriented spanning tree) in a given digraph with the maximum number of leaves. In this paper, we obtain two com- binatorial results on the number of leaves in out-branchings. We show that † every strongly connected n-vertex digraph D with minimum in- degree at least 3

Noga Alon; Fedor V. Fomin; Gregory Gutin

186

Spanning directed trees with many leaves  

Microsoft Academic Search

The Directed Maximum Leaf Out-Branching problem is to nd an out-branching (i.e. a rooted oriented spanning tree) in a given digraph with the maximum number of leaves. In this paper, we obtain two combinatorial results on the number of leaves in out-branchings. We show that { every strongly connected n-vertex digraph D with minimum in- degree at least 3 has

Noga Alon; Fedor V. Fomin; Gregory Gutin; Michael Krivelevich; Saket Saurabh

2008-01-01

187

Characteristics of photosynthesis in peach leaves  

Microsoft Academic Search

Seasonal photosynthetic patterns of Loring peach (Prunus persica (L). Batsch) leaves were monitored throughout the 1974 growing season. Using leaves on detached branches, CO2 exchange was measured under controlled light and temperature conditions. Net photosynthesis rate varied from 9 to 12.4 mg CO2 dm-2 leaf area h-1 and was correlated with fruit development, with the highest values occurring during the

C. E. Crews; S. L. Williams; H. M. Vines

1975-01-01

188

More manganese accumulates in maple sun leaves than in shade leaves.  

PubMed

Nuclear magnetic resonance and neutron activation analysis were used to measure manganese concentrations in leaves of Acer platanoides. Mn was found to accumulate in both the vacuoles and the chloroplasts, with more Mn (per unit area) in sun leaves than in shade leaves. No Mn was lost at senescence. Different seasonal patterns of Mn accumulation were found in sun and shade leaves. The quantity of chloroplast reserve Mn (bound to the outer surface of thylakoid membranes) increased rapidly in sun leaves from bud-break through midsummer, and then remained approximately constant through senescence. In shade leaves, however, the quantity of reserve Mn increased slowly, and at approximately a constant rate throughout the growing season. PMID:16666945

McCain, D C; Markley, J L

1989-08-01

189

Leaving home and leaving the state: evidence from the United States  

Microsoft Academic Search

Leaving the parental home is an important first step in a long-term housing career. We extend the previous research on this topic by examining the impact of housing market factors on the risks of leaving with or without a partner in the United States. We also re-examine the role of the income of the young adult leavers in nest-leaving, and

Clara H. Mulder; William A. V. Clark

2000-01-01

190

The extraction of characteristic wavebands for radish leaves and rice leaves based on LCTF imaging method  

NASA Astrophysics Data System (ADS)

In order to identify and classify horticultural crops rapidly, it is great importance of selecting effective characteristic wavebands from a large number of imaging data. Extracting effective characteristic wavebands can nearly represent holistic information of the research target from rich imaging spectral data, mainly used for rapid characteristic identification, cluster analysis and establishing database, especially in high spectral sensing to recognize targets for a long distance. The experiment chooses radish leaves and rice leaves as research samples so as to obtain spectral information from the surface of samples by interval of 5nm based on LCTF imaging; then, the standard deviation and correlation coefficient of the gray images are calculated for these two kinds of leaves; next, we calculate the value of waveband index according to standard deviation and correlation coefficient, and extract the effective characteristic wavebands for radish leaves and rice leaves through the sorting of waveband index. By those, the experimental results show there are six ideal wavebands at 530nm, 550nm, 555nm, 715nm, 510nm and 565nm for radish leaves, 645nm, 675nm, 685nm, 670nm, 690nm and 660nm for rice leaves separately. Further, according to the principle of Euclidean distance, we also give an assessment of classification accuracy for these two samples by comparing characteristic wavebands with full wavebands, and the classification accuracy of radish leaves and rice leaves is 80.00% and 86.67% respectively. Therefore, choosing these wavebands can be used as effective characteristic wavebands for radish leaves and rice leaves.

Cao, Peng-fei; Feng, Jie; Li, Hong-ning

2013-08-01

191

Adipogenic effects of piperlonguminine in 3T3-L1 cells and plasma concentrations of several amide constituents from Piper chaba extracts after treatment of mice.  

PubMed

In our previous study, piperlonguminine from the fruit of Piper chaba was reported to promote adipogenesis in 3T3-L1 cells like the peroxisome proliferator-activated receptor-? (PPAR?) agonist, troglitazone. In the present study, the mode of action of piperlonguminine in cells was examined. Piperlonguminine increased mRNA levels of adiponectin, glucose transporter 4, and fatty acid-binding protein (aP2). It also increased mRNA levels of PPAR?2 but, unlike troglitazone, piperlonguminine did not activate PPAR? directly in a nuclear receptor cofactor assay. Analyses of plasma from mice treated with piperlonguminine, piperine, and retrofractamide A, and an extract of the fruit, showed that concentrations of piperlonguminine were higher than those of piperine and retrofractamide A, and that the "area-under-the-curve" of piperine increased following in vivo administration of the extract. PMID:23584920

Yamaguchi, Itadaki; Matsuda, Hisashi; Zhang, Hailong; Hamao, Makoto; Yamashita, Chihiro; Kogami, Yuichiro; Kon'I, Haruka; Murata, Megumi; Nakamura, Seikou; Yoshikawa, Masayuki

2014-01-01

192

Decision to Leave Scale: Perceived Reasons to Stay in or Leave Violent Relationships  

ERIC Educational Resources Information Center

The 30-item Decision to Leave Scale (DLS) was developed with 631 college women and 420 college women and women in shelters. Seven DLS subscales emerged for concerns in deciding to stay or leave: Fear of Loneliness, Child Care Needs, Financial Problems, Social Embarrassment, Poor Social Support, Fear of Harm, Hopes Things Change. Mean internal…

Hendy, Helen M.; Eggen, Doreen; Gustitus, Cheryl; McLeod, Kelli C.; Ng, Phillip

2003-01-01

193

29 CFR 825.202 - Intermittent leave or reduced leave schedule.  

Code of Federal Regulations, 2011 CFR

...occasional basis for medical appointments, or leave taken several days at a time spread over a period of six months, such as for chemotherapy. A pregnant employee may take leave intermittently for prenatal examinations or for her own condition, such as for...

2011-07-01

194

29 CFR 825.202 - Intermittent leave or reduced leave schedule.  

Code of Federal Regulations, 2010 CFR

...occasional basis for medical appointments, or leave taken several days at a time spread over a period of six months, such as for chemotherapy. A pregnant employee may take leave intermittently for prenatal examinations or for her own condition, such as for...

2010-07-01

195

Leaves Antimicrobial Activity of Glycyrrhiza glabra L.  

PubMed

Licorice (Glycyrrhiza glabra L.) is an important medicinal plant. In this study, the antimicrobial activities of ethanolic and aqueous extracts from licorice leaves were studied compared to root extracts activities. Bacillus subtilis, Enterococcus faecalis, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli, and Candida albicans were used as test organisms. Antimicrobial activity was tested by paper disc agar diffusion and serial dilution methods in order to determine minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The root and leave extracts showed activity against Candida albicans, and tested gram-positive bacteria in a dose dependent manner. The ethanolic extract of the leaves was the most active extract against gram-positive bacteria. Its effectiveness against strains provides hope that it can serve as an alternative therapeutic agent. PMID:24381608

Irani, Mahboubeh; Sarmadi, Marziyeh; Bernard, Françoise; Ebrahimi Pour, Gholam Hossein; Shaker Bazarnov, Hossein

2010-01-01

196

Request for Leave of Absence Year Month Day  

E-print Network

B-1 Form B-1 Request for Leave of Absence Year Month Day Dean of the Graduate School Day Year Month Day Record of Study Abroad and Leaves of Absence in the past. Leave of Absence Year Month Day Year Month Day Leave of Absence Year Month Day Year Month Day

Sano, Masaki

197

Medical Leave of Absence Without Pay Request Georgia Southern University  

E-print Network

Medical Leave of Absence Without Pay Request Georgia Southern University Employee Name Request Justification: Medical leave without pay: Medical leave without pay may be granted for reasons including extenuating personal health problems or immediate family issues. Medical leaves of absence without

Hutcheon, James M.

198

5 CFR 630.605 - Computation of home leave.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Computation of home leave. 630.605 Section 630.605 Administrative...CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Home Leave § 630.605 Computation of home leave. (a) For each month of service...

2010-01-01

199

5 CFR 630.606 - Grant of home leave.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Grant of home leave. 630.606 Section 630.606 Administrative...CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Home Leave § 630.606 Grant of home leave. (a) Entitlement. Except as...

2010-01-01

200

Time & Leave Benefits Summary Executive Compensation Plan (ECP) Employees Annual Leave Employees accrue annual leave monthly as set forth below  

E-print Network

Department. Bereavement Leave Employees may take up to 4 days for the death of an immediate family member as defined below: Immediate family shall be defined as spouse; natural, foster, or step parent; grand child, the Domestic Partner of the employee and a child or parent of the Domestic Partner or any other relative

Rosen, Jay

201

The Pied Piper  

NSDL National Science Digital Library

An unusually thorough British pest identification website loaded with general arthropod information, most of it well illustrated. Sections dedicated to chemicals, and miscellaneous home intruders are especially nice additions. They also include a bit of their work ethic, which contributes nicely to the overall quality.

0000-00-00

202

DEPARTMENT WORKSHEET FAMILY AND MEDICAL LEAVE  

E-print Network

DEPARTMENT WORKSHEET FAMILY AND MEDICAL LEAVE This worksheet is to be used when (1) an employee Injury/Illness Worksheet within 1 work day. Contact the WC office at x4-3362 if you have any questions remainder of worksheet and LOA form. If both boxes are not checked, employee is not eligible for FML

Leistikow, Bruce N.

203

Disaster Leave Office of Human Resources  

E-print Network

Disaster Leave 6.28 Office of Human Resources Applies to: Faculty, staff, and graduate associates for further direction and compensation information 1 . The Ohio State University ­ Office of Human Resources of Human Resources 614-292-2800 ohrc@hr.osu.edu hr.osu.edu/elr Benefits Customer Service Center, Office

Howat, Ian M.

204

The Biology of Ageing in Leaves.  

ERIC Educational Resources Information Center

Describes laboratory procedures for observing the progressive change deciduous leaves undergo prior to abscission. Outlines the starch test, sugar test, extraction and chromatography of pigments, and experimental results. States that obtained results enable the events of leaf senescence to be correlated with the carbohydrate economy of a tree in…

Gill, John; And Others

1988-01-01

205

Compartmentation of storage compounds in peach leaves  

E-print Network

Compartmentation of storage compounds in peach leaves J.P. Gaudillère1 J. Schaeffer2 A. Moing A de Bordeaux /, 33405 Talence Cedex, France Introduction High leaf photosynthesis is achieved when into the phloem and exported to other parts of the plant. The study of interactions be- tween photosynthesis

Paris-Sud XI, Université de

206

Pharmacognosy of Cassia Alata Linn – leaves  

PubMed Central

Cassia alata Linn, Commonly known as semaiagathi in Tamil is well known for its various medicinal properties in Indian systems of medicine. Various parts of this plant are used as vermicide, astringent, purgative, expectorant and to treat skin diseases. The present work deals with the anatomy, quantitative microscopy, physical constants and fluorescence analysis of the plant leaves. PMID:22557177

Mohideen, S.; Sasikala, E.; ARUHAJ, P.

2005-01-01

207

Yeasts from the leaves of pasture plants  

Microsoft Academic Search

The yeast population upon the leaves of pasture plants in New Zealand has been investigated in relation to season, soil yeast flora, and incidence of facial eczema toxin in autumn pasture. Leaf yeasts were shown to be taxonomically distinct from soil yeasts and to vary with season but not to vary with the localities sampled. During most of the year

M. E. di Menna

1959-01-01

208

Paid Leave Programs Policy 6.27  

E-print Network

vacation, sick, parental, jury duty/court appearance and organ donation leave to respond to employee needs; or death of an immediate family member. Definitions Term Definition Active pay status Conditions under-child of the adoptive parent. Adoptive parent A parent who has taken a child into one's family, through legal means

Howat, Ian M.

209

5 CFR 630.1203 - Leave entitlement.  

Code of Federal Regulations, 2010 CFR

...the notification and medical certification requirements...entitlement to family and medical leave. However, if...returning to work. In such cases, the incapacity of the...documented by a written medical certification from...The 12-month period referred to in paragraph...

2010-01-01

210

House of Leaves: The End of Postmodernism  

Microsoft Academic Search

Mark Z. Danielewski’s debut 2000 novel House of Leaves is written in part as an essay titled The Navidson Record by Zampanò. Within this essay, Zampanò includes footnotes and citations to many works both real and fictional. Through investigating some of his footnotes and allusions in The Navidson Record, certain connections to the postmodern movement may be drawn. By interpreting

Joseph B Noah

2012-01-01

211

29 CFR 825.202 - Intermittent leave or reduced leave schedule.  

Code of Federal Regulations, 2012 CFR

... 825.202 Section 825.202 Labor Regulations Relating to Labor (Continued) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR OTHER LAWS THE FAMILY AND MEDICAL...825.113 and 825.127. (c) Birth or placement . When leave is...

2012-07-01

212

29 CFR 825.202 - Intermittent leave or reduced leave schedule.  

... 825.202 Section 825.202 Labor Regulations Relating to Labor (Continued) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR OTHER LAWS THE FAMILY AND MEDICAL...825.113 and 825.127. (c) Birth or placement. When leave is...

2014-07-01

213

29 CFR 825.202 - Intermittent leave or reduced leave schedule.  

Code of Federal Regulations, 2013 CFR

... 825.202 Section 825.202 Labor Regulations Relating to Labor (Continued) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR OTHER LAWS THE FAMILY AND MEDICAL...825.113 and 825.127. (c) Birth or placement. When leave is...

2013-07-01

214

In vitro antimicrobial activity of olive leaves.  

PubMed

We investigated the antimicrobial effect of olive leaves against bacteria and fungi. The microorganisms tested were inoculated in various concentrations of olive leaf water extract. Olive leaf 0.6% (w/v) water extract killed almost all bacteria tested, within 3 h. Dermatophytes were inhibited by 1.25% (w/v) plant extract following a 3-day exposure whereas Candida albicans was killed following a 24 h incubation in the presence of 15% (w/v) plant extract. Olive leaf extract fractions, obtained by dialysis, that showed antimicrobial activity consisted of particles smaller than 1000 molecular rate cutoffs. Scanning electron microscopic observations of C. albicans, exposed to 40% (w/v) olive leaf extract, showed invaginated and amorphous cells. Escherichia coli cells, subjected to a similar treatment but exposed to only 0.6% (w/v) olive leaf extract showed complete destruction. These findings suggest an antimicrobial potential for olive leaves. PMID:12870202

Markin, D; Duek, L; Berdicevsky, I

2003-04-01

215

The Metabolism of Oat Leaves during Senescence  

PubMed Central

The senescence of the first leaves of light-grown Avena seedlings when detached and placed in the dark is inhibited by ?, ??-dipyridyl and ?, ??, ??-tripyridyl at concentrations between 10?5 and 10?4 M. Five other chelating agents exert similar inhibiting effects at concentrations 3 to 30 times higher. The senescence of etiolated leaves, as shown by loss of carotenoid and protein, is similarly inhibited. Ethylene-diaminetetraacetate has a similar effect in the dark, though only at 10 mM and above, but in the light it causes bleaching of chlorophyll. It is deduced that an iron-containing system plays an essential part in the initiation of the senescence process. PMID:16659244

Tetley, Richard M.; Thimann, Kenneth V.

1975-01-01

216

Antinociceptive activity of Gynandropsis gynandra leaves.  

PubMed

Gynandropsis gynandra (Capparidaceae) leaves are traditionally used in the treatment of pain. In order to evaluate the scientific validity of this, leaves were extracted successively to produce various extracts. These extracts were screened for antinociceptive activity using the hot plate test and acetic acid-induced writhing test in mice at a dose of 100 mg kg(-1), intraperitoneally. Ethanol and aqueous extracts were found most active in both the tests. The action was blocked by naloxone (1 mg kg(-1), s.c.) in the hot plate test, which suggests involvement of opioid receptors in the action. Flavonoids and tannins were observed in the active extracts, so we can say that they may responsible for the antinociceptive activity. PMID:19296373

Ghogare, U R; Nirmal, S A; Patil, R Y; Kharya, M D

2009-01-01

217

Nurses’ intentions to leave nursing in Finland  

Microsoft Academic Search

The shortage of nurses is a problem in many countries. We examined how factors related to wage, work, job satisfaction\\/dissatisfaction,\\u000a and workplace or demographic factors were associated with nurses’ intentions to switch from health care to non-health-care\\u000a roles. Wage and share of income from shift work were negatively and statistically significantly related to nurses’ intention\\u000a to leave the health care

T. Kankaanranta; P. Rissanen

2008-01-01

218

Morphology of leaves cuticle by fringe projection  

NASA Astrophysics Data System (ADS)

The development of this work is important in the morphological study of plant parts, specifically in the study of the cuticle of fruits or leaves. The implemented optical technique for fringe projection can identify potential fracture zones which damage the presentation of the fruits impacting business as well as producing them. Specifically, we obtained information on the thickness of a cuticle corresponding to the abaxial surface of a leaf of apple (Malus domestica) of the variety Golden Delicious.

Martínez, Amalia; Rayas Alvarez, J. A.; Cordero, Raúl; Balieiro R., Daniela

2011-10-01

219

Saponins from the leaves of Mimusops laurifolia.  

PubMed

Fifteen new bidesmosidic triterpenoid saponins (1-15) were isolated from a methanol extract of the leaves of Mimusops laurifolia. Their structures were established using one- and two-dimensional NMR spectroscopy and mass spectrometry and determined to be bidesmosides of protobassic acid (2-4, 11, 12, and 15) and of 16alpha-hydroxyprotobassic acid (1, 5-10, 13, and 14). PMID:15974604

Eskander, Jacqueline; Lavaud, Catherine; Abdel-Khalik, Soad M; Soliman, Hesham S M; Mahmoud, Ibrahim I; Long, Christophe

2005-06-01

220

Polysaccharide from the leaves of Phytolacca americana  

Microsoft Academic Search

A polysaccharide has been isolated from the leaves ofPhytolacca americana and has been characterized. It has been established that it contains residues of galactose, arabinose, xylose, and rhamnose,\\u000a in a ratio of 3:4:1:3 and also D-galacturonic acid (85–90%). The results obtained permit the polysaccharide to be assigned\\u000a to the class of pectin substances.

L. A. Chistyakova; S. I. Denisova

1982-01-01

221

The cost of sickness: on the effect of the duration of sick leave on post-sick leave earnings.  

PubMed

Studies analysing the effect of the duration of sick leave on subsequent labour market outcomes do not consider the potential endogenous relationship between duration and labour market outcomes. This paper deals with this shortcoming by using a consistent estimator attained through Instrumental Variables methods for estimating the effect of the duration of a sick leave spell on post-sick leave earnings. I use Danish administrative data and a major 2001 reform of the sick leave system as the instrument for duration. I find that the duration of a sick leave spell has both short and long term effects on post-sick leave earnings. PMID:20207060

Andersen, Signe Hald

2010-05-01

222

Carbon fluxes in mature peach leaves.  

PubMed

The turnover and transport of sugars are described in peach (Prunus persica L. Batsch), a species exporting both sucrose and sorbitol. Apparent export rate was slower in peach leaves than in leaves of herbaceous species. Sorbitol was the major soluble end product of photosynthesis and the major soluble carbohydrate in the leaf (higher than sucrose). Carbon fluxes were described using (14)C labeling, radioactivity loss curves, and compartmental analysis during the second half of the photoperiod when chemical steady state was reached for soluble carbohydrates. The measured specific radioactivity of sucrose was typical of a primary product. The delayed decrease in specific radioactivity of sorbitol indicated that part of it was secondarily synthesized. Sucrose is proposed to be the carbon source for the delayed synthesis of sorbitol in the light. The sorbitol to sucrose ratio was higher in the petiole than in the leaf tissues. In phloem sap, obtained using stylectomy of aphids and collected from the main stem between source leaves and apex, this ratio was lower than in the petiole, suggesting a preferential sorbitol demand by sinks. PMID:16653212

Moing, A; Carbonne, F; Rashad, M H; Gaudillère, J P

1992-12-01

223

Characterization of ?-Galactosidase from Cucumber Leaves 1  

PubMed Central

Two forms of ?-galactosidase (?-d-galactoside galactohydrolase, E.C. 3.2.1.22) which differed in molecular weight were resolved from Cucumis sativus L. leaves. The enzymes were partially purified using ammonium sulfate fractionation, Sephadex gel filtration, and diethylaminoethyl-Sephadex chromatography. The molecular weights of the two forms, by gel filtration, were 50,000 and 25,000. The 50,000-dalton form comprised approximately 84% of the total ?-galactosidase activity in crude extracts from mature leaves and was purified 132-fold. The partially purified 25,000-molecular weight form rapidly lost activity unless stabilized with 0.2% albumin and accounted for 16% of the total ?-galactosidase activity in the crude extract. The smaller molecular weight form was not found in older leaves. The two forms were similar in several ways including their pH optima which were 5.2 and 5.5 for the 50,000- and 25,000-dalton form, respectively, and activation energies, which were 15.4 and 18.9 kilocalories per mole for the larger and smaller forms. Both enzymes were inhibited by galactose as well as by excess concentrations of p-nitrophenyl-?-d-galactoside sub-strate. Km values with this substrate and with raffinose and melibiose were different for each substrate, but similar for both forms of the enzyme. With stachyose, Km values were 10 and 30 millimolar for the 50,000- and 25,000- molecular weight forms, respectively. PMID:16661511

Smart, Elizabeth L.; Pharr, David M.

1980-01-01

224

Differential Localization of Antioxidants in Maize Leaves.  

PubMed Central

The aim of this work was to determine the compartmentation of antioxidants between the bundle-sheath and mesophyll cells of maize (Zea mays L.) leaves. Rapid fractionation of the mesophyll compartment was used to minimize modifications in the antioxidant status and composition due to extraction procedures. The purity of the mesophyll isolates was assessed via the distribution of enzyme and metabolite markers. Ribulose-1,5 bisphosphate and ribulose-1,5-bisphosphate carboxylase/oxygenase were used as bundle-sheath markers and phosphoenolpyruvate carboxylase was used as the mesophyll marker enzyme. Glutathione reductase and dehydroascorbate reductase were almost exclusively localized in the mesophyll tissue, whereas ascorbate, ascorbate peroxidase, and superoxide dismutase were largely absent from the mesophyll fraction. Catalase, reduced glutathione, and monodehydroascorbate reductase were found to be approximately equally distributed between the two cell types. It is interesting that, whereas H2O2 levels were relatively high in maize leaves, this oxidant was largely restricted to the mesophyll compartment. We conclude that the antioxidants in maize leaves are partitioned between the two cell types according to the availability of reducing power and NADPH and that oxidized glutathione and dehydroascorbate produced in the bundle-sheat tissues have to be transported to the mesophyll for re-reduction to their reduced forms. PMID:12223757

Doulis, A. G.; Debian, N.; Kingston-Smith, A. H.; Foyer, C. H.

1997-01-01

225

Division of Human Resources Leave for Active Military Duty  

E-print Network

Division of Human Resources Leave for Active Military Duty Human Resources / Attendance and Leave recalled to active duty, it is critical that the Division of Human Resources is immediately notified. A military leave impacts terms and conditions of employment and staff and the Division of Human Resources

Meyers, Steven D.

226

Human Resources Division FMLA INTERMITTENT LEAVE TRACKING FORM  

E-print Network

1/06 Human Resources Division FMLA INTERMITTENT LEAVE TRACKING FORM Record hours used for approved FMLA leave purposes An FMLA Intermittent Leave Tracking Form must be submitted to the Human Resources: Supervisor Signature Date: Return Completed Tracking Form by Campus Mail, US Mail, or Fax to: Human Resources

Provancher, William

227

RESTORATION OF ANNUAL LEAVE CHECKLIST Exigency of the Smithsonian  

E-print Network

RESTORATION OF ANNUAL LEAVE CHECKLIST Exigency of the Smithsonian Employee schedules use year. Employee submits a request for restoration because of exigency through the supervisor of the leave year, but no later than January 31 of the new leave year The request for restoration should

228

Leave with Pay Bond/Waiver of Bond Form  

E-print Network

Leave with Pay Bond/Waiver of Bond Form Submit to: The Office of Faculty Affairs and Professional Development, ADM 451 I. As you were granted a leave with pay, you must either post a bond in the amount of the salary to be paid during the leave or be granted a waiver of the bond. Most faculty members request

229

Protein and fiber contents in alfalfa leaves and stems  

Microsoft Academic Search

SUMMARY - Alfalfa leaves and stems contain different protein and fiber concentration in different stages of growth. The objective of the study was to determine a dynamic of nutrient accumulation in leaves and stems. The experiment was conducted in two consecutive years (1999, 2000) on three cultivars (Slavonka, Vuka and Os-88). Chemical analysis of leaves and stems were obtained from

S. Popovic; M. Stjepanovic; S. Grljusic; T. Cupic; M. Tucak

230

29 CFR 825.120 - Leave for pregnancy or birth.  

...2014-07-01 false Leave for pregnancy or birth. 825.120 Section 825.120 Labor... § 825.120 Leave for pregnancy or birth. (a) General rules. Eligible...entitled to FMLA leave for pregnancy or birth of a child as follows: (1) Both...

2014-07-01

231

29 CFR 825.120 - Leave for pregnancy or birth.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Leave for pregnancy or birth. 825.120 Section 825.120 Labor... § 825.120 Leave for pregnancy or birth. (a) General rules. Eligible...entitled to FMLA leave for pregnancy or birth of a child as follows: (1) Both...

2010-07-01

232

29 CFR 825.120 - Leave for pregnancy or birth.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Leave for pregnancy or birth. 825.120 Section 825.120 Labor... § 825.120 Leave for pregnancy or birth. (a) General rules. Eligible...entitled to FMLA leave for pregnancy or birth of a child as follows: (1) Both...

2013-07-01

233

29 CFR 825.120 - Leave for pregnancy or birth.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Leave for pregnancy or birth. 825.120 Section 825.120 Labor... § 825.120 Leave for pregnancy or birth. (a) General rules. Eligible...entitled to FMLA leave for pregnancy or birth of a child as follows: (1) Both...

2012-07-01

234

29 CFR 825.120 - Leave for pregnancy or birth.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Leave for pregnancy or birth. 825.120 Section 825.120 Labor... § 825.120 Leave for pregnancy or birth. (a) General rules. Eligible...entitled to FMLA leave for pregnancy or birth of a child as follows: (1) Both...

2011-07-01

235

Leaving home: ;;The housing aspirations of young disabled people  

Microsoft Academic Search

This article explores the housing experiences and aspirations of young disabled people in Scotland. Those who leave the family home in crisis experience several housing moves before settling; those who leave in a planned way tend to stay in their first home. Young people aspiring to leave the parental home are limited to a social housing tenancy, as a result

Jo Dean

2003-01-01

236

Cytokine-mimetic properties of some Philippine food and medicinal plants.  

PubMed

This study evaluated Philippine indigenous plants for cytokine-mimetic properties and partially characterized candidate mimetics for their stability as well as their sensitivity to variations in temperature and pH. Forty-five plant extract preparations were tested for their ability to stimulate proliferation of mouse spleen cells and bone marrow cells. Temperature and pH effects were determined by subjecting the extracts to different temperature and pH levels and measuring their residual proliferative activities. Results revealed that 24 and 14 extracts were able to stimulate proliferation of bone marrow cells and spleen cells, respectively. Extracts from yam (Dioscorea alata L.) (Dioscoreaceae) roots and leaves, taro (Colocasia esculenta L.) (Araceae) roots, and buyo (Piper betle L.) (Piperaceae) leaf were among the extracts that strongly stimulated proliferation of both bone marrow cells and splenocytes, significantly increasing cell concentrations. Heating the extracts beyond 40 degrees C markedly reduced their proliferative ability, while a pH level below 4.0 and above 8.0 also significantly decreased the extracts' activity. Three protein-mimetics with sizes of 26 kDa, 35 kDa, and 50 kDa were isolated from buyo leaf, yam root, and taro root extracts, respectively. All three molecules are biologically active and stimulate a dose-dependent proliferative response. PMID:17651065

Tulin, Edgardo E; Ecleo, Zenaida T

2007-06-01

237

Mitochondrial electron transport protects floating leaves of long leaf pondweed (Potamogeton nodosus Poir) against photoinhibition: comparison with submerged leaves.  

PubMed

Investigations were carried to unravel mechanism(s) for higher tolerance of floating over submerged leaves of long leaf pondweed (Potamogeton nodosus Poir) against photoinhibition. Chloroplasts from floating leaves showed ~5- and ~6.4-fold higher Photosystem (PS) I (reduced dichlorophenol-indophenol ? methyl viologen ? O2) and PS II (H2O ? parabenzoquine) activities over those from submerged leaves. The saturating rate (V max) of PS II activity of chloroplasts from floating and submerged leaves reached at ~600 and ~230 µmol photons m(-2) s(-1), respectively. Photosynthetic electron transport rate in floating leaves was over 5-fold higher than in submerged leaves. Further, floating leaves, as compared to submerged leaves, showed higher F v/F m (variable to maximum chlorophyll fluorescence, a reflection of PS II efficiency), as well as a higher potential to withstand photoinhibitory damage by high light (1,200 µmol photons m(-2) s(-1)). Cells of floating leaves had not only higher mitochondria to chloroplast ratio, but also showed many mitochondria in close vicinity of chloroplasts. Electron transport (NADH ? O2; succinate ? O2) in isolated mitochondria of floating leaves was sensitive to both cyanide (CN(-)) and salicylhydroxamic acid (SHAM), whereas those in submerged leaves were sensitive to CN(-), but virtually insensitive to SHAM, revealing the presence of alternative oxidase in mitochondria of floating, but not of submerged, leaves. Further, the potential of floating leaves to withstand photoinhibitory damage was significantly reduced in the presence of CN(-) and SHAM, individually and in combination. Our experimental results establish that floating leaves possess better photosynthetic efficiency and capacity to withstand photoinhibition compared to submerged leaves; and mitochondria play a pivotal role in protecting photosynthetic machinery of floating leaves against photoinhibition, most likely by oxidation of NAD(P)H and reduction of O2. PMID:25366828

Shabnam, Nisha; Sharmila, P; Sharma, Anuradha; Strasser, Reto J; Govindjee; Pardha-Saradhi, P

2014-11-01

238

Evaluation of the Effectiveness of Piper cubeba Extract in the Amelioration of CCl4-Induced Liver Injuries and Oxidative Damage in the Rodent Model.  

PubMed

Background. Liver diseases still represent a major health burden worldwide. Moreover, medicinal plants have gained popularity in the treatment of several diseases including liver. Thus, the present study was to evaluate the effectiveness of Piper cubeba fruits in the amelioration of CCl4-induced liver injuries and oxidative damage in the rodent model. Methods. Hepatoprotective activity was assessed using various biochemical parameters like SGOT, SGPT, ?-GGT, ALP, total bilirubin, LDH, and total protein. Meanwhile, in vivo antioxidant activities as LPO, NP-SH, and CAT were measured in rat liver as well as mRNA expression of cytokines such as TNF?, IL-6, and IL-10 and stress related genes iNOS and HO-1 were determined by RT-PCR. The extent of liver damage was also analyzed through histopathological observations. Results. Treatment with PCEE significantly and dose dependently prevented drug induced increase in serum levels of hepatic enzymes. Furthermore, PCEE significantly reduced the lipid peroxidation in the liver tissue and restored activities of defense antioxidant enzymes NP-SH and CAT towards normal levels. The administration of PCEE significantly downregulated the CCl4-induced proinflammatory cytokines TNF? and IL-6 mRNA expression in dose dependent manner, while it upregulated the IL-10 and induced hepatoprotective effect by downregulating mRNA expression of iNOS and HO-1 gene. PMID:25654097

AlSaid, Mansour; Mothana, Ramzi; Raish, Mohammad; Al-Sohaibani, Mohammed; Al-Yahya, Mohammed; Ahmad, Ajaz; Al-Dosari, Mohammed; Rafatullah, Syed

2015-01-01

239

Piper nigrum Leaf and Stem Assisted Green Synthesis of Silver Nanoparticles and Evaluation of Its Antibacterial Activity Against Agricultural Plant Pathogens  

PubMed Central

Utilization of biological materials in synthesis of nanoparticles is one of the hottest topics in modern nanoscience and nanotechnology. In the present investigation, the silver nanoparticles were synthesized by using the leaf and stem extract of Piper nigrum. The synthesized nanoparticle was characterized by UV-vis spectroscopy, X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), energy dispersive X-ray analysis (EDAX), and Fourier Transform Infrared Spectroscopy (FTIR). The observation of the peak at 460?nm in the UV-vis spectra for leaf- and stem-synthesized silver nanoparticles reveals the reduction of silver metal ions into silver nanoparticles. Further, XRD analysis has been carried out to confirm the crystalline nature of the synthesized silver nanoparticles. The TEM images show that the leaf- and stem-synthesized silver nanoparticles were within the size of about 7–50?nm and 9–30?nm, respectively. The FTIR analysis was performed to identify the possible functional groups involved in the synthesis of silver nanoparticles. Further, the antibacterial activity of the green-synthesized silver nanoparticles was examined against agricultural plant pathogens. The antibacterial property of silver nanoparticles is a beneficial application in the field of agricultural nanotechnology. PMID:24558336

Paulkumar, Kanniah; Gnanajobitha, Gnanadhas; Vanaja, Mahendran; Rajeshkumar, Shanmugam; Malarkodi, Chelladurai; Pandian, Kannaiyan; Annadurai, Gurusamy

2014-01-01

240

Bioactivity of Piper hispidinervum (Piperales: Piperaceae) and Syzygium aromaticum (Myrtales: Myrtaceae) oils, with or without formulated Bta on the biology and immunology of Spodoptera frugiperda (Lepidoptera: Noctuidae).  

PubMed

The combination of essential oils and Bacillus thuringiensis Berliner may represent an interesting control strategy. Thus, the study tested the following hypothesis: the combination of long pepper oil (Piper hispidinervum L.) and clove (Syzygium aromaticum L.) oils in two concentrations with Xentari WG (Bta) yields a more effective control of Spodoptera frugiperda (JE Smith) (Lepidoptera: Noctuidae) affecting biological and reproductive parameters and leading to changes in the levels of phenoloxidase and nitric oxide in the hemolymph of the pest. The results demonstrate that only long pepper oil, at the highest concentration with Xentari WG (Bta), promotes reduced larval survival. However, both oils with or without the insecticide interfere in the biology and humoral immunity of S.frugiperda. All treatments caused a decrease in the amount of eggs, except for the clove oil at both concentrations without Bta. Therefore, the use of these oils is a promising alternative for the integrated management of S. frugiperda; however, its association with Bta demonstrated no significant increase in their efficiency. PMID:24665696

Cruz, G S; Wanderley-Teixeira, V; Oliveira, J V; Correia, A A; Breda, M O; Alves, T J S; Cunha, F M; Teixeira, A A C; Dutra, K A; Navarro, D M A F

2014-02-01

241

Evaluation of the Effectiveness of Piper cubeba Extract in the Amelioration of CCl4-Induced Liver Injuries and Oxidative Damage in the Rodent Model  

PubMed Central

Background. Liver diseases still represent a major health burden worldwide. Moreover, medicinal plants have gained popularity in the treatment of several diseases including liver. Thus, the present study was to evaluate the effectiveness of Piper cubeba fruits in the amelioration of CCl4-induced liver injuries and oxidative damage in the rodent model. Methods. Hepatoprotective activity was assessed using various biochemical parameters like SGOT, SGPT, ?-GGT, ALP, total bilirubin, LDH, and total protein. Meanwhile, in vivo antioxidant activities as LPO, NP-SH, and CAT were measured in rat liver as well as mRNA expression of cytokines such as TNF?, IL-6, and IL-10 and stress related genes iNOS and HO-1 were determined by RT-PCR. The extent of liver damage was also analyzed through histopathological observations. Results. Treatment with PCEE significantly and dose dependently prevented drug induced increase in serum levels of hepatic enzymes. Furthermore, PCEE significantly reduced the lipid peroxidation in the liver tissue and restored activities of defense antioxidant enzymes NP-SH and CAT towards normal levels. The administration of PCEE significantly downregulated the CCl4-induced proinflammatory cytokines TNF? and IL-6 mRNA expression in dose dependent manner, while it upregulated the IL-10 and induced hepatoprotective effect by downregulating mRNA expression of iNOS and HO-1 gene. PMID:25654097

AlSaid, Mansour; Mothana, Ramzi; Raish, Mohammad; Al-Sohaibani, Mohammed; Al-Yahya, Mohammed; Ahmad, Ajaz; Al-Dosari, Mohammed; Rafatullah, Syed

2015-01-01

242

Antioxidant, antiproliferative and antimicrobial activities of the volatile oil from the wild pepper Piper capense used in Cameroon as a culinary spice.  

PubMed

Wild pepper (Piper capense L.f., Piperaceae) is a spice traditionally used in western Cameroon to make soups called 'Nkui' and 'Nah poh'. In the present work, the essential oil hydrodistilled from fruits was analyzed by GC-FID and GC-MS, and for in vitro biological activities, namely cytotoxic, antioxidant and antimicrobial, by MTT, DPPH, ABTS and agar disc diffusion methods. The oil composition was dominated by monoterpene hydrocarbons (56.5%) responsible for the pepper odor, such as (beta-pinene (33.2%), sabinene (10.0%) and alpha-pinene (8.9%). The oil induced a concentration-dependent inhibitory effect on human tumor cells MDA-MB 231 (breast adenocarcinoma), A375 (malignant melanoma) and HCT116 (colon carcinoma), showing IC50 values of 26.3, 76.0 and 22.7 microg/ml, respectively. The oil showed total antioxidant activity with a Trolox equivalent antioxidant concentration (TEAC) value of 140 micromol/g. The essential oil of P. capense proved to be an effective scavenger of the ABTS+ radical, with an activity only about 30 times lower than that of Trolox. Moderate activity was observed against the Gram-positive species Staphylococcos aureus and Enterococcusfaecalis, and the yeast Candida albicans. The notable inhibition of some human tumor cells is worthy of further investigation to discover the possible mechanisms of action responsible for the observed cytotoxic effect of this essential oil. PMID:24555300

Woguem, Verlaine; Maggi, Filippo; Fogang, Hervet P D; Tapondjoua, Léon A; Womeni, Hilaire M; Luana, Quassinti; Bramuccic, Massimo; Vitali, Luca A; Petrelli, Dezemona; Lupidi, Giulio; Papa, Fabrizio; Vittori, Sauro; Barboni, Luciano

2013-12-01

243

Determination of kavalactones in dried kava (Piper methysticum) powder using near-infrared reflectance spectroscopy and partial least-squares regression.  

PubMed

Kava (Piper methysticum Forst F.), or àwa in the Hawaiian language, has been used for thousands of years by the people of the South Pacific Islands, in particular Fiji, Vanuatu, Tonga, and Samoa, for social and ceremonial occasions. Kava has the unique ability to promote a state of relaxation without the loss of mental alertness. Kava recently became part of the herbal pharmacopoeia throughout the United States and Europe because of its anxiolytic properties. The active compounds are collectively called kavalactones (or kava pyrones). The need for a less time-consuming and costly method to determine the concentration of kavalactones in dried kava is urgent. The combination of near-infrared reflectance spectroscopy (NIRS) and partial least-squares (PLS) methods has been found to be a convenient, versatile, and rapid analytical tool for determination of kavalactones in dried kava powder. Calibration equations were developed based on the analyses of 110 samples with variable physical and chemical properties collected over time from Hawaii kava growers and validated by analyses of a set of 12 samples with unknown kavalactones concentration. All six major kavalactones and the total kavalactones were measured using NIRS with accuracy acceptable for commercial use. The NIRS measurements are reproducible and have a repeatability on a par with HPLC methods. PMID:16910700

Gautz, Loren D; Kaufusi, Pakieli; Jackson, Mel C; Bittenbender, Harry C; Tang, Chung-Shih

2006-08-23

244

Inhibition of monoamine oxidase by derivatives of piperine, an alkaloid from the pepper plant Piper nigrum, for possible use in Parkinson's disease.  

PubMed

A series of compounds related to piperine and antiepilepsirine was screened in a monoamine oxidase A and B assay. Piperine is an alkaloid from the source plant of both black and white pepper grains, Piper nigrum. Piperine has been shown to have a wide range of activity, including MAO inhibitory activity. The z-factor for the screening assay was found to be greater than 0.8 for both assays. Notably, the compounds tested were selective towards MAO-B, with the most potent compound having an IC(50) of 498 nM. To estimate blood-brain barrier (BBB) permeability, we used a PAMPA assay, which suggested that the compounds are likely to penetrate the BBB. A fluorescent bovine serum albumin (BSA) high-throughput screening (HTS) binding assay showed an affinity of 8 ?M for piperine, with more modest binding for other test compounds. Taken together, the data described here may be useful in gaining insight towards the design of selective MAO-B inhibitory compounds devoid of MAO-A activity. PMID:23102654

Al-Baghdadi, Osamah B; Prater, Natalie I; Van der Schyf, Cornelis J; Geldenhuys, Werner J

2012-12-01

245

Achieving reliability and high accuracy in automated protein docking: ClusPro, PIPER, SDU, and stability analysis in CAPRI rounds 13-19.  

PubMed

Our approach to protein-protein docking includes three main steps. First, we run PIPER, a rigid body docking program based on the Fast Fourier Transform (FFT) correlation approach, extended to use pairwise interactions potentials. Second, the 1000 best energy conformations are clustered, and the 30 largest clusters are retained for refinement. Third, the stability of the clusters is analyzed by short Monte Carlo simulations, and the structures are refined by the medium-range optimization method SDU. The first two steps of this approach are implemented in the ClusPro 2.0 protein-protein docking server. Despite being fully automated, the last step is computationally too expensive to be included in the server. When comparing the models obtained in CAPRI rounds 13-19 by ClusPro, by the refinement of the ClusPro predictions and by all predictor groups, we arrived at three conclusions. First, for the first time in the CAPRI history, our automated ClusPro server was able to compete with the best human predictor groups. Second, selecting the top ranked models, our current protocol reliably generates high-quality structures of protein-protein complexes from the structures of separately crystallized proteins, even in the absence of biological information, provided that there is limited backbone conformational change. Third, despite occasional successes, homology modeling requires further improvement to achieve reliable docking results. PMID:20818657

Kozakov, Dima; Hall, David R; Beglov, Dmitri; Brenke, Ryan; Comeau, Stephen R; Shen, Yang; Li, Keyong; Zheng, Jiefu; Vakili, Pirooz; Paschalidis, Ioannis Ch; Vajda, Sandor

2010-11-15

246

Antinociceptive activity of Ricinus communis L. leaves  

PubMed Central

Objective To evaluate the antinociceptive activity of the methanol extract of Ricinus communis leaves (MRCL). Methods Antinociceptive activity was evaluated using acetic acid induced writhing test, formalin induced paw licking and tail immersion method in mice at doses of 100, 125 and 150 mg/kg bw. Results The results indicated that MRCL exhibited considerable antinociceptive activity against three classical models of pain in mice. Preliminary phytochemical analysis suggested the presence of saponin, steroids and alkaloids. Conclusions It can be concluded that MRCL possesses antinociceptive potential that may be due to saponin, steroids and alkaloids in it. PMID:23569744

Taur, Dnyaneshwar J; Waghmare, Maruti G; Bandal, Rajendra S; Patil, Ravindra Y

2011-01-01

247

Triterpenoids from the leaves of Psidium guajava  

Microsoft Academic Search

Two triterpenoids, 20?-acetoxy-2?,3?-dihydroxyurs-12-en-28-oic acid (guavanoic acid, 3), and 2?,3?-dihydroxy-24-p-z-coumaroyloxyurs-12-en-28-oic acid (guavacoumaric acid, 7), along with six known compounds 2?-hydroxyursolic acid (1), jacoumaric acid (2), isoneriucoumaric acid (4), asiatic acid (5), ilelatifol D (6) and ?-sitosterol-3-O-?-d-glucopyranoside (8), have been isolated from the leaves of Psidium guajava. Their structures were determined through spectroscopic methods. Compound 5 showed dose-dependent (10–500 ?g\\/ml) spasmolytic activity

Sabira Begum; Syed Imran Hassan; Bina S Siddiqui; Farhana Shaheen; M Nabeel Ghayur; Anwar H Gilani

2002-01-01

248

Random walks between leaves of random networks  

NASA Astrophysics Data System (ADS)

Motivated by the desire to model internet traffic we consider random walks that start and are absorbed on the leaves of random networks and study the length of such walks. We present and test two techniques to analyse these walks. On Erd?s-Rényi random graphs where the probability of a walk decays exponentially with its length, the methods give indistinguishable results for the decay exponent. This simple form of decay is not apparent on heterogeneous networks such as Barabási-Albert scale free networks and in this case each technique is demonstrated to have a different strength.

Lancaster, David

2014-02-01

249

Acylated flavonol glycosides from Eugenia jambolana leaves.  

PubMed

Two acylated flavonol glycosides and 15 known polyphenols have been isolated and identified from the leaves of Eugenca jambolana Lam. The structures of the new compounds were identified as 3-O-(4"-O-acetyl)-alpha-L-rhamnopyranoside of mearnsetin (myricetin 4'-methyl ether) and myricetin 3-O-(4"-O-acetyl-2"-O-galloyl)-alpha-L-rhamnopyranoside. The complete structure elucidation of all isolated metabolites based on chemical and spectroscopic methods of analysis (UV, 1D and 2D NMR) as well as negative ESI-MS with and without CID in-source fragmentation. PMID:11738415

Mahmoud, I I; Marzouk, M S; Moharram, F A; El-Gindi, M R; Hassan, A M

2001-12-01

250

Antihistaminic effect of Bauhinia racemosa leaves  

PubMed Central

Bauhinia racemosa Lam. (Caesalpiniaceae) leaves have been used in the treatment of asthma traditionally and we therefore undertook this study to scientifically validate its benefit in asthma using suitable animal models. Antihistaminic principles are known to be useful in the treatment of asthma; hence, in the present work, the antihistaminic activity of an ethanol extract of B. racemosa (at a dose of 50 mg/kg, i.p.) was assessed using clonidine-induced catalepsy and haloperidol-induced catalepsy in Swiss albino mice. The results showed that the ethanol extract inhibits clonidine-induced catalepsy but there is no effect on haloperidol-induced catalepsy. This suggests that the inhibition is through an antihistaminic action and that there is no role of dopamine. Hence, we concluded that the ethanol extract has significant antihistaminic activity. The polar constituents in the ethanol extract of leaves of B. racemosa may be responsible for the antihistaminic activity and B. racemosa may therefore have a role in the treatment of asthma. PMID:21731358

Nirmal, SA; Laware, RB; Rathi, R A; Dhasade, VV; Kuchekar, BS

2011-01-01

251

Ecojustice in science education: leaving the classroom  

NASA Astrophysics Data System (ADS)

Eduardo Dopico and Eva Garcia-Vázquez's article enriched the ecojustice literature with an interesting metaphor of leaving the classroom, which I argue for here. Glasson and Boggs help to highlight the challenges and fortitude of working ecojustice perspectives in science education and the ways that a dialogical conversation addresses the world at large rather than focusing narrowly and exclusively on science education. Considering the metaphor of `leaving the classroom' I want to explore the tensions that can be experienced by science educators who do research focused on ecosocial justice. While it is not a new idea to suggest that there are gatekeepers in science education who try to maintain what counts in terms of impact in the classroom and what counts or not for the purposes of doing good work in science education, I anticipate highlighting the tensions that ecojustice educators may experience and why they can and should persevere with the incisive work that they are doing to conserve the prospects of future generations. Ecojustice no longer belongs constrained under the confines of environmental sciences or environmental education in science education. It is a separate and distinct field of study that should be generally accepted for the ways it brings clarity and conversation to ideas, curriculum studies, and thick descriptions of how people engage in eco-justice and ethics.

Mueller, Michael P.

2011-06-01

252

Amino Acid Metabolism of Pea Leaves  

PubMed Central

In the young leaves of pea (Pisum sativum L.) plants, there was a diurnal variation in the levels of amino acids. In the light, total amino nitrogen increased for the first few hours, then stabilized; in the dark, there was a transient decrease followed by a gradual recovery. Asparagine, homoserine, alanine, and glutamine accounted for much of these changes. The incorporation of 15N into various components of the young leaves was followed after supply of 15N-nitrate. 15N appeared most rapidly in ammonia, due to reduction in the leaf, and this process took place predominantly in the light. A large proportion of the primary assimilation took place through the amide group of glutamine, which became labeled and turned over rapidly; labeling of glutamic acid and alanine was also rapid. Asparagine (amide group) soon became labeled and showed considerable turnover. Slower incorporation and turnover were found for aspartic acid, ?-aminobutyric acid, and homoserine. Synthesis and turnover of all of the amino acids continued at a low rate in the dark. ?-Aminobutyric acid was the only compound found to label more rapidly in the dark than in the light. PMID:16659967

Bauer, Alfred; Urquhart, Aileen A.; Joy, Kenneth W.

1977-01-01

253

Metabolism of Oat Leaves during Senescence 1  

PubMed Central

In air largely freed from CO2, senescence of isolated oat (Avena sativa cv Victory) seedling leaves is no longer prevented by white light; instead, the leaves lose both chlorophyll and protein as rapidly as in the dark. Senescence in light is also accelerated in pure O2, but it is greatly delayed in N2; 100% N2 preserves both protein and chlorophyll in light and in darkness. In light in air, most of the compounds tested that had previously been found to delay or inhibit senescence in darkness actually promote the loss of chlorophyll, but they do not promote proteolysis. Under these conditions, proteolysis can therefore be separated from chlorophyll loss. But in light minus CO2, where chlorophyll loss is rapid in controls, two of these same reagents prevent the chlorophyll loss. Unlike the many reagents whose action in light is thus the opposite of that in darkness, abscisic acid, which promotes chlorophyll loss in the dark, also promotes it in light with or without CO2. Kinetin, which prevents chlorophyll loss in the dark, also prevents it in light minus CO2. In general, therefore, the responses to light minus CO2 are similar to the responses to darkness, and (with the exception of abscisic acid and kinetin) opposite to the response to light in air. PMID:16662800

Satler, Sergio O.; Thimann, Kenneth V.

1983-01-01

254

5 CFR 630.1103 - Establishment of an emergency leave transfer program.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Establishment of an emergency leave transfer program. 630.1103...SERVICE REGULATIONS ABSENCE AND LEAVE Emergency Leave Transfer Program § 630.1103 Establishment of an emergency leave transfer program....

2010-01-01

255

5 CFR 630.1105 - Application to become an emergency leave recipient.  

Code of Federal Regulations, 2010 CFR

... false Application to become an emergency leave recipient. 630.1105 Section...REGULATIONS ABSENCE AND LEAVE Emergency Leave Transfer Program § 630.1105 Application to become an emergency leave recipient. (a) An...

2010-01-01

256

Environmental controls over methanol emission from leaves  

NASA Astrophysics Data System (ADS)

Methanol is found throughout the troposphere, with average concentrations second only to methane among atmospheric hydrocarbons. Proposed global methanol budgets are highly uncertain, but all agree that at least 60% of the total source arises from the terrestrial biosphere and primary emissions from plants. However, the magnitude of these emissions is also highly uncertain, and the environmental factors which control them require further elucidation. Using a temperature-controlled leaf enclosure, we measured methanol emissions from leaves of six plant species by proton transfer reaction mass spectrometry, with simultaneous measurements of leaf evapotranspiration and stomatal conductance. Rates of emission at 30°C varied from 0.2 to 38 ?g g (dry mass)-1 h-1, with higher rates measured on young leaves, consistent with the production of methanol via pectin demethylation in expanding foliage. On average, emissions increased by a factor of 2.3 for each 10°C increase in leaf temperature. At constant temperature, emissions were also correlated with co-varying incident photosynthetic photon flux density and rates of stomatal conductance. The data were analyzed using the emission model developed by Niinemets and Reichstein (2003a, b), with the incorporation of a methanol production term that increased exponentially with temperature. It was concluded that control of emissions, during daytime, was shared by leaf temperature and stomatal conductance, although rates of production may also vary diurnally in response to variations in leaf growth rate in expanding leaves. The model, which generally provided reasonable simulations of the measured data during the day, significantly overestimated emissions on two sets of measurements made through the night, suggesting that production rates of methanol were reduced at night, perhaps because leaf growth was reduced or possibly through a direct effect of light on production. Although the short-term dynamics of methanol emissions can be successfully modeled only if stomatal conductance and compound solubility are taken into account, emissions on longer time scales will be determined by rates of methanol production, controls over which remain to be investigated.

Harley, P.; Greenberg, J.; Niinemets, É.; Guenther, A.

2007-12-01

257

Environmental controls over methanol emission from leaves  

NASA Astrophysics Data System (ADS)

Methanol is found throughout the troposphere, with average concentrations second only to methane among atmospheric hydrocarbons. Proposed global methanol budgets are highly uncertain, but all agree that at least 60% of the total source arises from the terrestrial biosphere and primary emissions from plants. However, the magnitude of these emissions is also highly uncertain, and the environmental factors which control them require further elucidation. Using a temperature-controlled leaf enclosure, we measured methanol emissions from leaves of six plant species by proton transfer reaction mass spectrometry, with simultaneous measurements of leaf evapotranspiration and stomatal conductance. Rates of emission at 30°C varied from 0.3 to 38 ?g g (dry mass)-1 h-1, with higher rates measured on young leaves, consistent with the production of methanol via pectin demethylation in expanding foliage. On average, emissions increased by a factor of 2.4 for each 10°C increase in leaf temperature. At constant temperature, emissions were also correlated with co-varying incident photosynthetic photon flux density and rates of stomatal conductance. The data were analyzed using the emission model developed by Niinemets and Reichstein (2003a, b), with the incorporation of a methanol production term that increased exponentially with temperature. It was concluded that control of emissions, during daytime, was shared by leaf temperature and stomatal conductance, although rates of production may also vary diurnally in response to variations in leaf growth rate in expanding leaves. The model, which generally provided reasonable simulations of the measured data during the day, significantly overestimated emissions on two sets of measurements made through the night, suggesting that production rates of methanol were reduced at night, perhaps because leaf growth was reduced or possibly through a direct effect of light on production. Although the short-term dynamics of methanol emissions can be successfully modeled only if stomatal conductance and compound solubility are taken into account, emissions on longer time scales will be determined by rates of methanol production, controls over which remain to be investigated.

Harley, P.; Greenberg, J.; Niinemets, Ü.; Guenther, A.

2007-08-01

258

Leaving and entering a career in physics  

NASA Astrophysics Data System (ADS)

Although a continuous research career is desirable for physicists, women often face situations that force them to interrupt their careers. Concerning the career-break problem, we discussed four issues. First, we analyzed the factors that force women to leave physics. Second, we discussed the effects of an interruption in a physics career. Should women continue to work as scientists without any break, at all costs? Or is it possible (and perhaps even better) to choose a more flexible career path? Third, we discussed the ways to retain women in physics. As an example, we focused on one of the most difficult problems: dual-career couples. Finally, we also discussed some possible ways in which one could support and facilitate women returning to a physics career after a break.

Narasimhan, Shobhana; Tajima, Setsuko; Yoon, Jin-Hee

2013-03-01

259

Steroids from Dysoxylum grande (Meliaceae) leaves.  

PubMed

Seven new 23-oxo-cholestane derivatives named as grandol A (1), B (2), C (3), D (4), E (5), F (6), and G (7) were isolated from Dysoxylum grande leaves alongside with a new 3,4-secodammar-4(28)-en-3-oic acid derivative (8). The structures of the compounds were elucidated based on the interpretation of spectroscopic data, and their relative configurations were established by NOESY 2D NMR data. All of the isolates were tested for anti-acetylcholinesterase activity using thin layer chromatography (TLC)-bioautography with fast blue B salt. Only grandol A (1) and B (2) showed positive results, with clear discoloration at a concentration of 12.5 ppm. However, the obtained IC(50) values for grandol A and B, when using Ellman's method, were not significant (>200 ?g/ml). PMID:23178158

Wah, Low Kok; Abas, Faridah; Cordell, Geoffrey A; Ito, Hideyuki; Ismail, Intan Safinar

2013-02-01

260

The bionomics of Liriomyza Trifolii on Gypsophila and Bean Leaves  

Microsoft Academic Search

A study was carried out to determine the distribution of feeding and oviposition punctures made byLiriomyza trifolii Burgess on gypsophila(Gypsophila paniculata ) and bean(Phaseolus vulgaris) leaves, and the development times of the immature stages on these plants. The absolute number of punctures per leaf area\\u000a was much greater on bean leaves than on gypsophila leaves. The number of mines per

Jeanine H. W. M. Van Elferen; Shoshana Yathom

1989-01-01

261

Reversal of chromoplasts to chloroplasts in Buxus leaves  

Microsoft Academic Search

The ultrastructural changes in plastids ofBuxus sempervirens L. leaves were observed during their seasonal yellowing and regreening. The disintegration of chloroplasts into globular\\u000a type chromoplasts in yellowing leaves and their direct restoration to functional chloroplasts again in regreening leaves were\\u000a followed.\\u000a \\u000a The results presented an example of recent information indicating the essential sense of the reversible reciprocation of plastid\\u000a transformation.

Hiroyuki Koiwa; Taiji Ikeda; Yoshio Yoshida

1986-01-01

262

Piperidine alkaloids from Piper retrofractum Vahl. protect against high-fat diet-induced obesity by regulating lipid metabolism and activating AMP-activated protein kinase.  

PubMed

The fruits of Piper retrofractum Vahl. have been used for their anti-flatulent, expectorant, antitussive, antifungal, and appetizing properties in traditional medicine, and they are reported to possess gastroprotective and cholesterol-lowering properties. However, their anti-obesity activity remains unexplored. The present study was conducted to isolate the anti-obesity constituents from P. retrofractum Vahl. and evaluate their effects in high-fat diet (HFD)-induced obese mice. Piperidine alkaloids from P. retrofractum Vahl. (PRPAs), including piperine, pipernonaline, and dehydropipernonaline, were isolated as the anti-obesity constituents through a peroxisome proliferator-activated receptor ? (PPAR?) transactivation assay. The molecular mechanism was investigated in 3T3-L1 adipocytes and L6 myocytes. PRPA treatment activated AMP-activated protein kinase (AMPK) signaling and PPAR? protein and also regulated the expression of lipid metabolism-related proteins. In the animal model, oral PRPA administration (50, 100, or 300mg/kg/day for 8weeks) significantly reduced HFD-induced body weight gain without altering the amount of food intake. Fat pad mass was reduced in the PRPA treatment groups, as evidenced by reduced adipocyte size. In addition, elevated serum levels of total cholesterol, low-density lipoprotein cholesterol, total lipid, leptin, and lipase were suppressed by PRPA treatment. PRPA also protected against the development of nonalcoholic fatty liver by decreasing hepatic triglyceride accumulation. Consistent with the in vitro results, PRPA activated AMPK signaling and altered the expression of lipid metabolism-related proteins in liver and skeletal muscle. Taken together, these findings demonstrate that PRPAs attenuate HFD-induced obesity by activating AMPK and PPAR?, and regulate lipid metabolism, suggesting their potential anti-obesity effects. PMID:21741367

Kim, Kyung Jin; Lee, Myoung-Su; Jo, Keunae; Hwang, Jae-Kwan

2011-07-22

263

Oil from Tobacco Leaves: FOLIUM - Installation of Hydrocarbon Accumulating Pathways in Tobacco Leaves  

SciTech Connect

PETRO Project: LBNL is modifying tobacco to enable it to directly produce fuel molecules in its leaves for use as a biofuel. Tobacco is a good crop for biofuels production because it is an outstanding biomass crop, has a long history of cultivation, does not compete with the national food supply, and is highly responsive to genetic manipulation. LBNL will incorporate traits for hydrocarbon biosynthesis from cyanobacteria and algae, and enhance light utilization and carbon uptake in tobacco, improving the efficiency of photosynthesis so more fuel can be produced in the leaves. The tobacco-generated biofuels can be processed for gasoline, jet fuel or diesel alternatives. LBNL is also working to optimize methods for planting, cultivating and harvesting tobacco to increase biomass production several-fold over the level of traditional growing techniques.

None

2012-01-01

264

Work-family balance after childbirth: the association between employer-offered leave characteristics and maternity leave duration.  

PubMed

Early return to work after childbirth has been increasing among working mothers in the US. We assessed the relationship between access to employer-offered maternity leave (EOML) (both paid and unpaid) and uptake and duration of maternity leave following childbirth in a socio-economically diverse sample of full-time working women. We focus on California, a state that has long provided more generous maternity leave benefits than those offered by federal maternity leave policies through the State Disability Insurance program. The sample included 691 mothers who gave birth in Southern California in 2002-2003. Using weighted logistic regression, we examined the EOML-maternity leave duration relationship, controlling for whether the leave was paid, as well as other occupational, personality and health-related covariates. Compared with mothers who were offered more than 12 weeks of maternity leave, mothers with <6 weeks of EOML and those offered 6-12 weeks had five times higher odds of returning to work within 12 weeks; those offered no leave had six times higher odds of an early return. These relationships were similar after controlling for whether the leave was paid and after controlling for other occupational and health characteristics. Access to and duration of employer-offered maternity leave significantly determine timing of return to work following childbirth, potentially affecting work-family balance. Policy makers should recognize the pivotal role of employers in offering job security during and after maternity leave and consider widening the eligibility criteria of the Family and Medical Leave Act. PMID:23504130

Guendelman, Sylvia; Goodman, Julia; Kharrazi, Martin; Lahiff, Maureen

2014-01-01

265

Conserved host-pathogen PPIs. Globally conserved inter-species bacterial PPIs based conserved host-pathogen interactome derived novel target in C. pseudotuberculosis, C. diphtheriae, M. tuberculosis, C. ulcerans, Y. pestis, and E. coli targeted by Piper betel compounds.  

PubMed

Although attempts have been made to unveil protein-protein and host-pathogen interactions based on molecular insights of important biological events and pathogenesis in various organisms, these efforts have not yet been reported in Corynebacterium pseudotuberculosis (Cp), the causative agent of Caseous Lymphadenitis (CLA). In this study, we used computational approaches to develop common conserved intra-species protein-protein interaction (PPI) networks first time for four Cp strains (Cp FRC41, Cp 316, Cp 3/99-5, and Cp P54B96) followed by development of a common conserved inter-species bacterial PPI using conserved proteins in multiple pathogens (Y. pestis, M. tuberculosis, C. diphtheriae, C. ulcerans, E. coli, and all four Cp strains) and E. Coli based experimentally validated PPI data. Furthermore, the interacting proteins in the common conserved inter-species bacterial PPI were used to generate a conserved host-pathogen interaction (HP-PPI) network considering human, goat, sheep, bovine, and horse as hosts. The HP-PPI network was validated, and acetate kinase (Ack) was identified as a novel broad spectrum target. Ceftiofur, penicillin, and two natural compounds derived from Piper betel were predicted to inhibit Ack activity. One of these Piper betel compounds found to inhibit E. coli O157:H7 growth similar to penicillin. The target specificity of these betel compounds, their effects on other studied pathogens, and other in silico results are currently being validated and the results are promising. PMID:23288366

Barh, Debmalya; Gupta, Krishnakant; Jain, Neha; Khatri, Gourav; León-Sicairos, Nidia; Canizalez-Roman, Adrian; Tiwari, Sandeep; Verma, Ankit; Rahangdale, Sachin; Shah Hassan, Syed; dos Santos, Anderson Rodrigues; Ali, Amjad; Guimarães, Luis Carlos; Thiago Jucá Ramos, Rommel; Devarapalli, Pratap; Barve, Neha; Bakhtiar, Marriam; Kumavath, Ranjith; Ghosh, Preetam; Miyoshi, Anderson; Silva, Artur; Kumar, Anil; Misra, Amarendra Narayan; Blum, Kenneth; Baumbach, Jan; Azevedo, Vasco

2013-03-01

266

[Effects of Piper longum L. on chills in Japanese young women: time-dependent changes in skin surface temperature and its recovery rate following the exposure to mild cold stress].  

PubMed

Chills can lead to problems such as insomnia, mental fatigue, and unstable emotions. Increasing evidence shows that young women, as well as menopausal women, suffer from chills. The present study investigated the effect of Piper longum L. on chills in young women. Participants with (n = 16) and without (n = 16) chills were sampled randomly from female university students using reported discriminative criteria (Yamada et al, 2007). Each participant was randomly assigned to low- (15 mg) and high-dose (30 mg) P. longum groups. We determined the severity of complaints related to chills, physical parameters (body mass index, body fat ratio, and blood pressure), the peripheral circulation dynamics using a laser tissue blood flow-meter, and the skin surface temperature in the fingers using a thermograph. Mild cold stress was applied 10 min after taking a capsule containing P. longum or a dextrin placebo. Then, a thermograph was recorded every minute for 11 min. Piper longum significantly facilitated the recovery of skin surface temperature at either low or high dosages in participants with chills. In subjects without chills, neither high- nor low-dosage of P. longum had an effect. Our findings have important implications for the utility of P. longum in women with chills. PMID:19326811

Yamada, Noriko; Nishihara, Chie; Yoshimura, Hiroyuki; Yamaguchi, Yasunaga; Takagaki, Ryoji; Miyakoshi, Masazumi; Mizutani, Kenji

2009-02-01

267

Ensilage of cardboard and date palm leaves.  

PubMed

Eight treatments of cardboard (CB) and date palm leaves (DPL) with or without alkali treatments plus molasses, dates, and ammonium sulfate were ensiled in laboratory silos. Latobacillus plantarum and Saccharomyces cerevisiae inoculants were added at an application rate of 10(5) cfu/g of silage to study their possible influence on the fermentation process. Silos were sealed and incubated at 30 degrees C. The anaerobic ensiling was evaluated for chemical and microbiological variables by opening the silos after 30, 60, and 90 days. After 90 days, significantly low pH values (5.2-3.5) were obtained. The percentages of hemicellulose, cellulose, lignin, and ash were determined. Concentrations of reducing sugars, ether extract, and crude protein tended to be acceptable among treatments. Silages showed a significantly high lactic acid concentration (up to 4.3%) and only traces of butyric acid (below 1%). Also changes in acetic and propionic acids concentrations were determined. Lactobacillus populations remained almost static while yeast and molds populations tended to be lower after 90 days of ensilage. Neither alkali treatment nor microbial inoculants showed a relationship with the ensiling process. Thus, overall, it was concluded that CB and DPL can be effectively ensiled and the resultant silages are acceptable to merit their use as ruminant feed in arid regions. PMID:15027834

Baroon, Z; El-Nawawy, A S; Al-Othman, A

2004-01-01

268

Maltose Biochemistry and Transport in Plant Leaves  

SciTech Connect

Transitory starch builds up in photosynthesizing leaves during the day and is then degraded each night. It has recently been shown through mutant analysis and genetically engineered plants that transitory starch is required for maximal rates of photosynthesis, especially in high carbon dioxide atmospheres. Understanding the pathway by which carbon is exported from chloroplasts at night is limited. Previous work has shown that starch conversion to sucrose at night involves maltose export from chloroplasts. This pathway for carbon export from chloroplasts normally does not occur during the day. The regulation of maltose formation, the transporters that allow export of maltose from the chloroplast, and the cytosolic reactions by which maltose is converted to sucrose remain obscure. Genomic and biochemical approaches are proposed here to address maltose metabolism and transport. The research will cover three areas (1) how are hydrolytic and phosphorylytic starch degradation regulated, (2) how is maltose exported from chloroplasts, and (3) how is maltose converted to sucrose in the cytosol? It is expected that this research will lead to new insights about photosynthesis at high carbon dioxide levels, how carbon is partitioned in plants, and how partitioning can be altered to adapt plants to human needs.

Weber, Andreas P.M.

2008-04-25

269

Phytotoxins from the leaves of Ruta graveolens.  

PubMed

Bioassay-guided fractionation of the ethyl acetate extract of Ruta graveolens (common rue) leaves led to the isolation of the furanocoumarins 5-methoxypsoralen (5-MOP), 8-methoxypsoralen (8-MOP), and the quinolone alkaloid graveoline as phytotoxic constituents. Graveoline and 8-MOP substantially inhibited growth of Lactuca sativa (lettuce) seedlings and reduced chlorophyll content at 100 microM; this effect was not due to a direct effect on chlorophyll synthesis. Radical growth of L. sativa was inhibited by 10 microM 8-MOP. Graveoline inhibited growth of Lemna paucicostata (duckweed) at 100 microM. This is the first report of the phytotoxic activity of graveoline. Growth of Agrostis stolonifera (bentgrass) was inhibited by 5-MOP at 30 microM. All three compounds substantially reduced cell division in Allium cepa (onion) at or below 100 microM. None of the compounds caused significant cellular leakage of Cucumis sativus (cucumber) cotyledon disks at 100 microM. All three compounds inhibit plant growth, at least partially through inhibition of cell division. PMID:15161195

Hale, Amber L; Meepagala, Kumudini M; Oliva, Anna; Aliotta, Giovanni; Duke, Stephen O

2004-06-01

270

Life-history strategies affect aphid preference for yellowing leaves  

PubMed Central

According to the nutrient-translocation hypothesis, yellowing tree leaves are colonized by aphids at the end of the growing season owing to improved availability of nutrients in the phloem sap after chlorophyll degradation. We measured aphid densities on potted Betula pendula seedlings in a field site where a small proportion of foliage rapidly turned yellow before normal autumn coloration as a consequence of root anoxia. The number of adults and nymphs of the birch-feeding specialist aphids Euceraphis betulae, Betulaphis brevipilosa and Callipterinella tuberculata were counted from leaves on each of the 222 plants. Aphids were detected on 19 per cent of green leaves and on 41 per cent of yellow leaves. There was no indication of aphid avoidance of yellow leaves, and the number of winged (alate) viviparous E. betulae adults and their nymphs were significantly higher on yellow leaves than on green leaves, while the numbers of apterous B. brevipilosa and C. tuberculata did not differ between the leaf colour types. Our result suggests that only aphid species with alate generation during colour change can take advantage of yellowing leaves. This may explain the exceptional abundance of E. betulae compared with other aphid species on birches. PMID:19535364

Holopainen, Jarmo K.; Semiz, Gürkan; Blande, James D.

2009-01-01

271

Endopeptidases during the development and senescence of Lolium temulentum leaves  

Microsoft Academic Search

The endopeptidase activity of Lolium temulentum leaf tissue was measured using azocasein as a substrate. The enzyme increased with leaf age, and also during senescence of excised leaf tissue. There were at least two distinct endopeptidase activities, characterized by different pH optima. The predominant form in leaves of intact plants was maximally active at pH 5. In detached leaves during

Karl Morris; Howard Thomas; Lyndon J. Rogers

1996-01-01

272

Request for Leave of Absence Heisei Year Month Day  

E-print Network

Month Day Dean of the Graduate School of Science, the University of Tokyo Date of Enrollment for the following reasons. Reason Duration Heisei Year Month Day to Heisei Year Month Day Past Study Abroad and Leaves of Absence Study Abroad Heisei Year Month Day to Heisei Year Month Day Leave of Absence Heisei

Sano, Masaki

273

Division of Human Resources Attendance & Leave Audit Procedures  

E-print Network

Division of Human Resources Attendance & Leave Audit Procedures Page | 1 Questions (813) 974 to access the HR A&L Website Home > A-Z Index > type in Human Resources in search box > HR Services/or the supervisor. #12;Division of Human Resources Attendance & Leave Audit Procedures Page | 2 Questions (813) 974

Meyers, Steven D.

274

PHARMACOGNOSTICAL STUDIES ON LEAVES OF ATAIANTIA MONOPHYIA CORREA  

PubMed Central

Leaves of Atalantia monophylla are used in chronic rheumatism and paralysis. The Pharmacognostical studies like histological characters, leaf constants, ash values and extractive values of leaves of Atalantia monophylla Corr were carried out. The preliminary phytochemical analysis were also carried out. PMID:22557099

Manimaran, S.; Sathya, S.; Subburaju, T.; Dhanabal, S. P.; Tamizhmani, T.; Nanjan, M.J.; Suresh, B.

2003-01-01

275

Fluidized and vibrofluidized shallow beds of fresh leaves  

Microsoft Academic Search

The fluid dynamics behavior of shallow fluidized and vibrofluidized beds operating with fresh leaves was investigated with the aim of exploring drying applications in a modified conveyor belt (MCB) system, which may be operated in a fixed- or fluidized-bed mode. Leaves of the specimens Duranta repens, Schinus molle, Coleus barbatus, Buxus sempervirens, and Bougainvillea spectabilis were tested with a range

Renata de Aquino Brito Lima; Maria do Carmo Ferreira

2011-01-01

276

Reasons that Orthodontic Faculty Teach and Consider Leaving Teaching.  

ERIC Educational Resources Information Center

Surveyed full-time (FT) and part-time (PT) orthodontic faculty about reasons for considering leaving academia. About 38 percent FT and 25 percent PT were currently considering leaving. The factors most important for FT were work-related: salary support, financial support of department, and control over work or destiny. For PTs, the reasons were:…

Kula, Katherine; Glaros, Alan; Larson, Brent; Tuncay, Orhan

2000-01-01

277

Disability & Medical Leave Resources A Guide for Employees  

E-print Network

Disability & Medical Leave Resources A Guide for Employees This guide is a resource for you if you are experiencing difficulties at work related to a disability or chronic medical condition. For example, you may: have a serious health condition and need medical leave be returning to work with restrictions

Saffman, Mark

278

Chicoric acid found in basil ( Ocimum basilicum L.) leaves  

Microsoft Academic Search

This is the first report to identify the presence of chicoric acid (cichoric acid; also known as dicaffeoyltartaric acid, which is a caffeic acid derivatized with tartaric acid) in basil leaves. Rosmarinic acid, chicoric acid and caftaric acid (in the order of most abundant to least; all derivatives of caffeic acid) were identified in fresh basil leaves. Rosmarinic acid was

Jungmin Lee; Carolyn F. Scagel

2009-01-01

279

Genotoxicity of Nicotiana tabacum leaves on Helix aspersa  

PubMed Central

Tobacco farmers are routinely exposed to complex mixtures of inorganic and organic chemicals present in tobacco leaves. In this study, we examined the genotoxicity of tobacco leaves in the snail Helix aspersa as a measure of the risk to human health. DNA damage was evaluated using the micronucleus test and the Comet assay and the concentration of cytochrome P450 enzymes was estimated. Two groups of snails were studied: one fed on tobacco leaves and one fed on lettuce (Lactuca sativa L) leaves (control group). All of the snails received leaves (tobacco and lettuce leaves were the only food provided) and water ad libitum. Hemolymph cells were collected after 0, 24, 48 and 72 h. The Comet assay and micronucleus test showed that exposure to tobacco leaves for different periods of time caused significant DNA damage. Inhibition of cytochrome P450 enzymes occurred only in the tobacco group. Chemical analysis indicated the presence of the alkaloid nicotine, coumarins, saponins, flavonoids and various metals. These results show that tobacco leaves are genotoxic in H. aspersa and inhibit cytochrome P450 activity, probably through the action of the complex chemical mixture present in the plant. PMID:23885210

da Silva, Fernanda R.; Erdtmann, Bernardo; Dalpiaz, Tiago; Nunes, Emilene; Ferraz, Alexandre; Martins, Tales L.C.; Dias, Johny F.; da Rosa, Darlan P.; Porawskie, Marilene; Bona, Silvia; da Silva, Juliana

2013-01-01

280

Secondary metabolite profiles in HLB-affected sweet orange leaves  

Technology Transfer Automated Retrieval System (TEKTRAN)

Preliminary analyses of methanolic extracts of orange leaves that are either healthy or symptomatic of citrus greening (HLB) have shown consistent differences in the profiles of important classes of phytochemicals. The main flavonoids in symptomatic and healthy leaves were monitored in the HPLC chro...

281

Organizational Justice and Social Workers' Intentions to Leave Agency Positions  

ERIC Educational Resources Information Center

The authors investigated the impact of organizational justice on social workers' intention to leave Korean social service agencies. Specifically, this study concentrated on the moderating effect of organizational justice on the relationship between burnout and intention to leave. The authors surveyed 218 front-line social workers from 51 social…

Kim, Tae Kuen; Solomon, Phyllis; Jang, Cinjae

2012-01-01

282

Nutritive Value of Tree Leaves m the Kansas Flint Hills  

E-print Network

w . 11 `c7 Nutritive Value of Tree Leaves m the Kansas Flint Hills JR. FORWOOD AND C.E. OWENSBY Flint Hills, the tons of tree leaves that fall to the ground each autumn are largely ignored MANAGEMENT 38(l), January 1985 We have observed cattle grazing Flint Hills rangeland in the fall selecting

Owensby, Clenton E.

283

The Features of Cotyledon Leaves of Buckwheat's Species Fagopyrum tataricum  

Microsoft Academic Search

Cotyledon leaves of 81 samples of world gene pool of tartary buckwheat were investigated. Their linear parameters were measured; their morphological description was submitted. High positive corre­ lation was established between linear parameters of cotyledon leaves and weight of 1000 grains. The distribution of samples on groups was conducted on the basis of these parameters.

Andriy V. Nikitchuk; Elena S. Alexeeva

284

THE HEIGHT DISTRIBUTION OF LEAVES IN ROOTED TREES  

E-print Network

THE HEIGHT DISTRIBUTION OF LEAVES IN ROOTED TREES Michael Drmota Technical University of Vienna meth- ods have been used. In addition the joint height distribution of two di#11;erent leaves-negative numbers ' 0 > 0, ' 1 #21; 0, ' 2 #21; 0; : : : , which are used to de#12;ne a weight !(T ) for any planted

Drmota, Michael

285

Extracts of ginkgo biloba leaves inhibit monoamine oxidase  

Microsoft Academic Search

Extracts of Ginkgo biloba leaves produce reversible inhibition of rat brain monoamine oxidase (MAO). Both MAO-A and -B types were inhibited to a similar extent. The MAO inhibitory compound(s) were present in dried or fresh Ginkgo biloba leaves as well as in commercially available capsules of Ginkgo biloba and appear to be heat stable with relatively low molecular weight. MAO

Helen L. White; Philip W. Scates; Barrett R. Cooper

1996-01-01

286

The Meaning of Korean Women's Career-Leaving Experience  

ERIC Educational Resources Information Center

What is the meaning of Korean women's career-leaving experience? To answer this question, this study adopted a hermeneutic phenomenology approach. My intention was to search for the deeper meaning of Korean women's career-leaving experience from their perspective. Ten Korean women who had left their careers due to their domestic roles in their…

Lee, Yu-Jin

2010-01-01

287

38 CFR 21.6340 - Leaves of absence.  

Code of Federal Regulations, 2012 CFR

...21.6070 through 21.6074. Leave may only be authorized for a veteran during a period of rehabilitation to the point of employability. (Authority: 38 U.S.C. 1524(b)) (b) Purpose. The purpose of the leave system is to enable the...

2012-07-01

288

38 CFR 21.6340 - Leaves of absence.  

...21.6070 through 21.6074. Leave may only be authorized for a veteran during a period of rehabilitation to the point of employability. (Authority: 38 U.S.C. 1524(b)) (b) Purpose. The purpose of the leave system is to enable the...

2014-07-01

289

Footprints and Fingerprints in Cyberspace: The Trail You Leave Behind.  

ERIC Educational Resources Information Center

Online users leave traces that others can find and use. Provides an overview of where and how users leave traces and what users can do to protect their privacy. Discusses Internet accounts; special files ("signature,""plan,""project,""file,""finger,""whois," and "vacation"); online use; e-mail and Usenet; patterns and trends; Web footprints and…

Dern, Daniel P.

1997-01-01

290

REGULAR PAPER Mitochondrial electron transport protects floating leaves of long  

E-print Network

higher Fv/Fm (variable to maximum chlorophyll fluorescence, a reflection of PS II efficiency), as well leaves possess better photosynthetic efficiency and capacity to withstand photoinhibition com- pared to submerged leaves; and mitochondria play a pivotal role in protecting photosynthetic machinery of floating

Govindjee

291

Enumerative sequences of leaves and nodes in rational trees  

E-print Network

of leaves or nodes in a rational tree. Let s be an IN-rational sequence of nonnegative numbers, that is a se in "Theoretical Computer Science 221, 1-2 (1999) 41-60" #12;A rational tree is a tree which has only a nite numberEnumerative sequences of leaves and nodes in rational trees Frederique Bassino Institut Gaspard

Boyer, Edmond

292

Extraction of tannin from fresh and preserved leaves  

Microsoft Academic Search

The extractability of tannin from fresh, lyophilized, and dried leaves collected at various times in the growing season was determined using the radial diffusion assay for protein-precipitating phenolics. The amount of tannin extracted depended on the method of leaf preservation and on the maturity of the leaf. Early in the season, more tannin was extracted from lyophilized leaves than from

Ann E. Hagerman

1988-01-01

293

First Grade Collecting Leaves with the book Leaf Man  

NSDL National Science Digital Library

This activity is takes place in nature and in the classroom. Students are gathering different types of leaves and naming characteristics of each then sorting them by those characteristics. Students then make a picture with leaves and writes 2-3 sentences about their picture using the characteristic words.

294

Page 1 of 8 ADJUSTING FURLOUGH LEAVE ACCRUAL BALANCES  

E-print Network

Page 1 of 8 ADJUSTING FURLOUGH LEAVE ACCRUAL BALANCES DESCRIPTION OF PROGRAMS The following program affects the furlough leave accrual balances of eligible faculty and staff: The Gift-Endowment Program (GEP. IMPLEMENTATION In order to ensure that campus records reflect an accurate furlough accrual balance, Departments

Yamamoto, Keith

295

ADJUSTING FURLOUGH LEAVE ACCRUAL BALANCES DESCRIPTION OF PROGRAMS  

E-print Network

ADJUSTING FURLOUGH LEAVE ACCRUAL BALANCES DESCRIPTION OF PROGRAMS The following program affects the furlough leave accrual balances for faculty: The Clinical Coverage Program (CCP) is being used they are paid. This document will provide guidance only for manually adjusting furlough balances as a result

Yamamoto, Keith

296

Page 1 of 7 ADJUSTING FURLOUGH LEAVE ACCRUAL BALANCES  

E-print Network

Page 1 of 7 ADJUSTING FURLOUGH LEAVE ACCRUAL BALANCES DESCRIPTION OF PROGRAMS The following program affects the furlough leave accrual balances for faculty: Over-the-cap ("NIH-OTC") DOS codes are used, as in the example below, the increase to an individual's furlough accrual balance will be negligible (less than one

Yamamoto, Keith

297

Leaving home in the Netherlands: when and in which  

Microsoft Academic Search

The paper addresses two aspects of leaving the parental home in the Netherlands: the timing of leaving home in the life course, and the outcome in terms of the first housing situation. We investigate to what extent the timing and the housing outcome are influenced by the child's and the parents' resources, and how they differ between spatial contexts and

Clara H. Mulder

298

Leaving home: A study of laboratory mouse pup independence  

Microsoft Academic Search

Juvenile wild house mice leave their mothers at 8 weeks (+). In contrast, laboratory strains of mice (lab mice) are typically ‘weaned’ at postnatal day (PND) 21. Lab mice might mature faster than their wild forebears; but if they do not, standard laboratory weaning likely involves maternal deprivation. We therefore investigated when lab mice voluntarily leave their mothers. C57BL\\/6J families

Allison Bechard; Georgia Mason

2010-01-01

299

Profiler Cheat Sheet For Online Leave Users Table of Contents  

E-print Network

Profiler Cheat Sheet For Online Leave Users Table of Contents DOCUMENT PURPOSE........................................................................... 9 Information Technology Services Last Updated November 4, 2009 #12;Profiler Cheat Sheet for Online see this: #12;Profiler Cheat Sheet for Online Leave Users v1 11/04/2009 Page 3 User Profile

Olsen, Stephen L.

300

Phenolic composition and antioxidant activity of Malus domestica leaves.  

PubMed

The aim of this study was to determine the composition and content of phenolic compounds in the ethanol extracts of apple leaves and to evaluate the antioxidant activity of these extracts. The total phenolic content was determined spectrophotometrically, as well as the total flavonoid content in the ethanol extracts of apple leaves and the antioxidant activity of these extracts, by the ABTS, DPPH, and FRAP assays. The highest amount of phenolic compounds and flavonoids as well as the highest antioxidant activity was determined in the ethanol extracts obtained from the apple leaves of the cv. Aldas. The analysis by the HPLC method revealed that phloridzin was a predominant component in the ethanol extracts of the apple leaves of all cultivars investigated. The following quercetin glycosides were identified and quantified in the ethanol extracts of apple leaves: hyperoside, isoquercitrin, avicularin, rutin, and quercitrin. Quercitrin was the major compound among quercetin glycosides. PMID:25302319

Liaudanskas, Mindaugas; Viškelis, Pranas; Raudonis, Raimondas; Kviklys, Darius; Uselis, Norbertas; Janulis, Valdimaras

2014-01-01

301

Phenolic Composition and Antioxidant Activity of Malus domestica Leaves  

PubMed Central

The aim of this study was to determine the composition and content of phenolic compounds in the ethanol extracts of apple leaves and to evaluate the antioxidant activity of these extracts. The total phenolic content was determined spectrophotometrically, as well as the total flavonoid content in the ethanol extracts of apple leaves and the antioxidant activity of these extracts, by the ABTS, DPPH, and FRAP assays. The highest amount of phenolic compounds and flavonoids as well as the highest antioxidant activity was determined in the ethanol extracts obtained from the apple leaves of the cv. Aldas. The analysis by the HPLC method revealed that phloridzin was a predominant component in the ethanol extracts of the apple leaves of all cultivars investigated. The following quercetin glycosides were identified and quantified in the ethanol extracts of apple leaves: hyperoside, isoquercitrin, avicularin, rutin, and quercitrin. Quercitrin was the major compound among quercetin glycosides. PMID:25302319

Viškelis, Pranas; Uselis, Norbertas

2014-01-01

302

Machine Recognition for Broad-Leaved Trees Based on Synthetic Features of Leaves Using Probabilistic Neural Network  

Microsoft Academic Search

This paper is to effectively solve the problem that the objects of traditional plant identification were too broad and the classification features of it were usually not synthetic and the recognition rate was always slightly low. This study gives one recognition approach, in which the shape features and the texture features of the leaves of broad-leaved trees combine, composing a

Huang Lin; He Peng

2008-01-01

303

Maltose Biochemistry and Transport in Plant Leaves  

SciTech Connect

Final Technical Report for DOE grant DE-FG02-04ER15565 Maltose Biochemistry and Transport in Plant Leaves PI Thomas D. Sharkey University of Wisconsin-Madison Starch is a desirable plant product for both food and biofuel. Leaf starch is ideal for use in biofuels because it does not compete with grain starch, which is used for food. Starch is accumulated in plant leaves during the day and broken down at night. If we can manipulate leaf starch breakdown it may be possible to design a plant that provides both grain starch for food and leaf starch for biofuel. The pathway of leaf starch breakdown was not known when this work started. Preliminary evidence had shown that maltose was the primary product of leaf starch breakdown (Weise, Weber & Sharkey, 2004) and that it was metabolized by a disproportionating enzyme called amylomaltase but given the initials DPE2 (Lu & Sharkey, 2004). In this work we showed that only one form of maltose was metabolically active (Weise et al., 2005a) and that maltose was located in two different places when the amylomaltase was knocked out but only inside the chloroplast when the maltose transporter was knocked out (Lu et al., 2006a). This allowed us to estimate the energetics of maltose export and to show that maltose export is more efficient than glucose export (Weise et al., 2005b). We examined how daylength affected starch breakdown rate and found that starch breakdown rate could respond to changes in daylength within one day (Lu, Gehan & Sharkey, 2005). We also were able to show a second starch breakdown pathway by chloroplastic starch phosphorylase (Weise et al., 2006). Work to this point was summarized in a review (Lu & Sharkey, 2006). We were able to show that the amylomaltase in plants could substitute for the amylomaltase in bacteria (Lu et al., 2006b). In this paper we also showed the importance of a second enzyme called alpha-glucan phosphorylase in starch breakdown. Finally, we were able to determine the enzymatic mechanism of the amylomaltase (Steichen, Petty & Sharkey, 2008). These results have laid the groundwork for manipulating plants for improved biofuel production. Lu Y., Gehan J.P. & Sharkey T.D. (2005) Daylength and circadian effects on starch degradation and maltose metabolism. Plant Physiology, 138, 2280-2291 Lu Y. & Sharkey T.D. (2004) The role of amylomaltase in maltose metabolism in the cytosol of photosynthetic cells. Planta, 218, 466-473 Lu Y. & Sharkey T.D. (2006) The importance of maltose in transitory starch breakdown. Plant, Cell and Environment, 29, 353-366 Lu Y., Steichen J.M., Weise S.E. & Sharkey T.D. (2006a) Cellular and organ level localization of maltose in maltose-excess Arabidopsis mutants. Planta, 224, 935-943 Lu Y., Steichen J.M., Yao J. & Sharkey T.D. (2006b) The role of cytosolic ?-glucan phosphorylase in maltose metabolism and the comparison of amylomaltase in Arabidopsis and E. coli. Plant Physiology, 142 878-889 Steichen J.M., Petty R.V. & Sharkey T.D. (2008) Domain characterization of a 4-?-glucanotransferase essential for maltose metabolism in photosynthetic leaves. J. Biol. Chem., 283, 20797-20804 Weise S.E., Kim K.S., Stewart R.P. & Sharkey T.D. (2005a) Beta-maltose is the metabolically active anomer of maltose during transitory starch degradation. Plant Physiology, 137, 756-761 Weise S.E., Schrader S.M., Kleinbeck K.R. & Sharkey T.D. (2006) Carbon balance and circadian regulation of hydrolytic and phosphorolytic breakdown of transitory starch. Plant Physiology, 141, 879-886 Weise S.E., Sharkey T.D., van der Est A. & Bruce D. (2005b) Energetics of carbon export from the chloroplast at night. In: Photosynthesis: Fundamental aspects to global perspectives, the proceedings of the 13th international congress on photosynthesis, pp. 816-818. International Society of Photosynthesis/Alliance Communications Group, Lawrence. Weise S.E., Weber A. & Sharkey T.D. (2004) Maltose is the major form of carbon exported from the chloroplast at night. Planta, 218, 474-482

Thomas D. Sharkey

2010-01-28

304

Green synthesis of gold nanoparticles using extracts of Artocarpus Lakoocha fruit and its leaves, and Eriobotrya Japonica leaves  

NASA Astrophysics Data System (ADS)

Gold nanoparticles (AuNPs) synthesis is demonstrated successfully using fresh young leaves of Artocarpus Lakoocha (A. Lakoocha), fruit pulp of A. Lakoocha and loquat (Eriobotrya Japonica) leaves. We have also compared green synthesis with chemical assisted tri-n-octyl-phosphine (TOP) stabilized gold nanoparticles. Samples were characterized with transmission electron microscopy (TEM), Fourier transform infrared spectroscopy and UV-Visible spectroscopy. TEM images have shown that the average size of the particles is 15.06, 36.8 and 25.08 nm for A. Lakoocha fruits, A. Lakoocha leaves and loquat leaves assisted gold nanoparticles, respectively. Hydrogen tetrachloroaurate is reduced and AuNPs are stabilized by phenols, hydroxyls and carboxyls groups such as terpenoids, flavonoids, tannins etc, present in young leaves and fruit extracts. It was observed that green synthesis using botanical extracts is a cost effective and non- toxic way for nanoparticle preparation.

Sharma, Ankita; Dhiman, Naresh; Singh, Bhanu P.; Gathania, Arvind K.

2014-04-01

305

Leishmania donovani pteridine reductase 1: comparative protein modeling and protein-ligand interaction studies of the leishmanicidal constituents isolated from the fruits of Piper longum.  

PubMed

Visceral leishmaniasis or kala-azar is caused by the dimorphic parasite Leishmania donovani in the Indian subcontinent. Treatment options for kala-azar are currently inadequate due to various limitations. Currently, drug discovery for leishmaniases is oriented towards rational drug design; the aim is to identify specific inhibitors that target particular metabolic activities as a possible means of controlling the parasites without affecting the host. Leishmania salvages pteridin from its host and reduces it using pteridine reductase 1 (PTR1, EC 1.5.1.33), which makes this reductase an excellent drug target. Recently, we identified six alkamides and one benzenoid compound from the n-hexane fraction of the fruit of Piper longum that possess potent leishmanicidal activity against promastigotes as well as axenic amastigotes. Based on a homology model derived for recombinant pteridine reductase isolated from a clinical isolate of L. donovani, we carried out molecular modeling and docking studies with these compounds to evaluate their binding affinity. A fairly good agreement between experimental data and the results of molecular modeling investigation of the bioactive and inactive compounds was observed. The amide group in the conjugated alkamides and the 3,4-methylenedioxystyrene moiety in the benzenoid compound acts as heads and the long aliphatic chain acts as a tail, thus playing important roles in the binding of the inhibitor to the appropriate position at the active site. The remarkably high activity of a component containing piperine and piperine isomers (3.36:1) as observed by our group prompted us to study the activities of all four isomers of piperine-piperine (2E,4E), isopiperine (2Z,4E), isochavicine (2E,4Z), and chavicine (2Z,4Z)-against LdPTR1. The maximum inhibitory effect was demonstrated by isochavicine. The identification of these predicted inhibitors of LdPTR1 allowed us to build up a stereoview of the structure of the binding site in relation to activity, affording significant information that should prove useful during the structure-based design of leishmanicidal drugs. PMID:22752544

Sahi, Shakti; Tewatia, Parul; Ghosal, Sabari

2012-12-01

306

Dose–response relation between physical activity and sick leave  

PubMed Central

Objective To investigate the dose–response relation between moderate and vigorous physical activity and sick leave in a working population. Methods Data were used from three large Dutch databases: two continuous, cross sectional surveys among a representative sample of the Dutch population and one prospective cohort study. A distinction was made between duration, frequency and intensity of physical activity. The outcome measure was the number of days of sick leave. Analyses of variance were used to compare sick leave (in days) for workers with different amounts of physical activity, in particular workers meeting the physical activity recommendations v those who did not. Linear and logistic regression analyses were used to obtain effect estimates in the prospective cohort study, with the generalised estimating equation (GEE) method. Results No relation was found between moderate physical activity and sick leave. In two databases, workers meeting the recommendation of vigorous physical activity (active at a vigorous level for at least three times a week) had significantly less sick leave: more than one day over two months and more than four days over a year. The duration of vigorous physical activity was not associated with sick leave. Conclusion Physical activity at a vigorous intensity level for at least three times a week, as in the CDC/ACSM recommendation, has a positive effect on sick leave. PMID:16432007

Proper, K I; van den Heuvel, S G; De Vroome, E M; Hildebrandt, V H; Van der Beek, A J

2006-01-01

307

Resveratrols in Grape Berry Skins and Leaves in Vitis Germplasm  

PubMed Central

Background Resveratrol is an important stilbene that benefits human health. However, it is only distributed in a few species including grape and is very expensive. At present, grape has been an important source resveratrol. However, the details are scarce on resveratrol distribution in different Vitis species or cultivars. Methodology/Principal Finding The composition and content of resveratrols were investigated by HPLC for assessing genotypic variation in berry skins and leaves of 75 grape cultivars, belonging to 3 species and 7 interspecific hybrids. Trans-resveratrol, cis-piceid and trans-piceid were detected in berry skins and leaves, but cis-resveratrol was not. Resveratrol content largely varied with genetic background as well as usage. In most cultivars, total resveratrol including the above three compounds was higher in berry skins than leaves. In berry skins of most cultivars and leaves of almost all cultivars, cis-piceid was the most abundant resveratrol; trans-resveratrol and trans-piceid were minor components. Some specific cultivars were found with extremely high levels of trans-resveratrol, cis- piceid, trans-piceid or total resveratrols in berry skins or leaves. In skins and leaves, rootstock cultivars had a higher content of total resveratrols, and the cultivated European type cultivars and their hybrids with V. labrusca had relatively low totals. There were no significant correlations of the amounts of total resveratrols or any individual resveratrol between berry skins and leaves. All 75 cultivars can be divided into four groups based on the composition of resveratrols and their concentration by principal component analysis. Conclusion Resveratrol content of grape berries and leaves varied largely with their genetic background and usage. Rootstock cultivars had a higher content of total resveratrols than the other germplasm. Total resveratrols were lower in leaves than berry skins in most cultivars. Cis-piceid was the most abundant resveratrol in most cultivars, and trans-res and trans-pd were minor components. PMID:23637874

Wang, Lijun; Xu, Man; Liu, Chunyan; Wang, Junfang; Xi, Huifen; Wu, Benhong; Loescher, Wayne; Duan, Wei; Fan, Peige; Li, Shaohua

2013-01-01

308

Photosynthate Partitioning in Soybean Leaves at Two Irradiance Levels  

PubMed Central

High irradiance-acclimated soybean leaves had the same CO2 exchange rates, but lower starch accumulation rates and correspondingly higher translocation rates than unacclimated leaves. Increased translocation rates were associated with increased sucrose phosphate synthetase (EC 2.4.1.14) activity. Foliar sucrose levels and adenosine diphosphate-glucose pyrophosphorylase (EC 2.7.7.9) activity were unaffected. Carbon assimilation, partitioning, and enzyme activity of unacclimated leaves were unaltered even after a second day's exposure to high irradiance. Results are consistent with the hypothesis that photosynthate partitioning between starch synthesis and sucrose translocation are controlled in part by the rate of sucrose synthesis. PMID:16661072

Silvius, John E.; Chatterton, N. Jerry; Kremer, Diane F.

1979-01-01

309

Photoinactivation of photosystem II in leaves.  

PubMed

Photoinactivation of Photosystem II (PS II), the light-induced loss of ability to evolve oxygen, inevitably occurs under any light environment in nature, counteracted by repair. Under certain conditions, the extent of photoinactivation of PS II depends on the photon exposure (light dosage, x), rather than the irradiance or duration of illumination per se, thus obeying the law of reciprocity of irradiance and duration of illumination, namely, that equal photon exposure produces an equal effect. If the probability of photoinactivation (p) of PS II is directly proportional to an increment in photon exposure (p = kDeltax, where k is the probability per unit photon exposure), it can be deduced that the number of active PS II complexes decreases exponentially as a function of photon exposure: N = Noexp(-kx). Further, since a photon exposure is usually achieved by varying the illumination time (t) at constant irradiance (I), N = Noexp(-kI t), i.e., N decreases exponentially with time, with a rate coefficient of photoinactivation kI, where the product kI is obviously directly proportional to I. Given that N = Noexp(-kx), the quantum yield of photoinactivation of PS II can be defined as -dN/dx = kN, which varies with the number of active PS II complexes remaining. Typically, the quantum yield of photoinactivation of PS II is ca. 0.1micromol PS II per mol photons at low photon exposure when repair is inhibited. That is, when about 10(7) photons have been received by leaf tissue, one PS II complex is inactivated. Some species such as grapevine have a much lower quantum yield of photoinactivation of PS II, even at a chilling temperature. Examination of the longer-term time course of photoinactivation of PS II in capsicum leaves reveals that the decrease in N deviates from a single-exponential decay when the majority of the PS II complexes are inactivated in the absence of repair. This can be attributed to the formation of strong quenchers in severely-photoinactivated PS II complexes, able to dissipate excitation energy efficiently and to protect the remaining active neighbours against damage by light. PMID:16049752

Chow, Wah Soon; Lee, Hae-Youn; He, Jie; Hendrickson, Luke; Hong, Young-Nam; Matsubara, Shizue

2005-06-01

310

Hydraulic design of leaves: insights from rehydration kinetics  

E-print Network

-like action of guard cells provides leaves with the ability to control rates of water loss to the environ- ment, stomatal closure involves the net movement of water out of cells and thus proceeds at a finite

Holbrook, N. Michele

311

A Postdoc's Guide to Pregnancy and Maternity Leave  

NSDL National Science Digital Library

This guide provides general information on pregnancy and maternity leave for postdocs, including tips for keeping your research going and talking with your supervisor. This guide is intended primarily for postdoc women who are pregnant or are planning for pregnancy.

Kathleen Flint Ehm (National Postdoctoral Association)

2011-10-05

312

Changes in spectral properties of detached birch leaves  

NASA Technical Reports Server (NTRS)

A study conducted in order to determine the rate of changes in spectral properties of detached leaves and to evaluate the effectiveness of low temperature and cytokinins for delaying the changes, is examined. For five minutes, leaves from red birch are immersed in water or 0.001 M BAP, and then stored in plastic bags in the dark at either 5 or 25 C. Using a spectroradiometer and an integrating sphere, total directional-hemispherical reflectance and transmittance of the adaxial surface of the leaves are measured over the 400-1100 nm wavelength region. The results indicate that for leaves stored at 5 C for one week, the changes in the spectral properties are less than 5 percent of the initial values, whereas storage at 25 C promotes rapid senescence and large changes in the spectral properties. It is shown that low temperature is more effective than BAP in delaying senescence.

Daughtry, C. S. T.; Biehl, L. L.

1985-01-01

313

Nurse manager job satisfaction and intent to leave.  

PubMed

An electronic survey was used to collect data from 291 nurse managers working in U.S. hospitals. Seventy percent were satisfied or very satisfied with their jobs and 68% were either likely or very likely to recommend nursing management as a career choice. Seventy-two percent of these nurse managers were also planning to leave their positions in the next 5 years. The four most common reasons reported for intent to leave included burnout, career change, retirement, and promotion. Burnout was the most common reason cited by the entire sample but the fourth most common reason for leaving cited by those nurse managers who were planning to leave and also satisfied or very satisfied with their positions. Recommendations for nursing leaders include evaluating the workload of nurse managers, providing career counseling, and developing succession plans. PMID:24689156

Warshawsky, Nora E; Havens, Donna S

2014-01-01

314

Indirect suppression of photosynthesis on individual leaves by arthropod herbivory  

E-print Network

REVIEW Indirect suppression of photosynthesis on individual leaves by arthropod herbivory Paul D imaging tech- nologies revealed that alterations to photosynthesis and transpiration propagate of herbivory on photosynthesis, measured by gas exchange or chlorophyll fluorescence, and identifies four

DeLucia, Evan H.

315

Indirect Suppression of Photosynthesis on Individual Leaves by Arthropod Herbivory  

E-print Network

REVIEW Indirect Suppression of Photosynthesis on Individual Leaves by Arthropod Herbivory PAUL D tissues are unaltered, and plant photosynthesis and water balance function normally. However, recent application of thermal and fluorescent imaging technologies revealed that alterations to photosynthesis

DeLucia, Evan H.

316

IET. Stack interior. Masons lay fire brick liner, leaving air ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

IET. Stack interior. Masons lay fire brick liner, leaving air layer between bricks and concrete wall. Date: May 20, 1955. INEEL negative no. 55-1306 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

317

29 CFR 825.201 - Leave to care for a parent.  

Code of Federal Regulations, 2010 CFR

...DEPARTMENT OF LABOR OTHER LAWS THE FAMILY AND MEDICAL LEAVE ACT OF 1993 Employee Leave Entitlements Under the Family and Medical Leave Act § 825.201...different operating divisions of the same company. On the other hand, if...

2010-07-01

318

29 CFR 825.121 - Leave for adoption or foster care.  

Code of Federal Regulations, 2010 CFR

...DEPARTMENT OF LABOR OTHER LAWS THE FAMILY AND MEDICAL LEAVE ACT OF 1993 Coverage Under the Family and Medical Leave Act § 825.121 Leave...different operating divisions of the same company. On the other hand, if one...

2010-07-01

319

38 CFR 21.348 - Leave following completion of a period of training or rehabilitation services.  

...CONTINUED) VOCATIONAL REHABILITATION AND EDUCATION Vocational Rehabilitation and Employment Under 38 U.S.C. Chapter 31 Leaves of Absence § 21.348 Leave following completion of a period of training or rehabilitation services. (a) Leave...

2014-07-01

320

38 CFR 21.348 - Leave following completion of a period of training or rehabilitation services.  

Code of Federal Regulations, 2011 CFR

...CONTINUED) VOCATIONAL REHABILITATION AND EDUCATION Vocational Rehabilitation and Employment Under 38 U.S.C. Chapter 31 Leaves of Absence § 21.348 Leave following completion of a period of training or rehabilitation services. (a) Leave...

2011-07-01

321

38 CFR 21.348 - Leave following completion of a period of training or rehabilitation services.  

Code of Federal Regulations, 2010 CFR

...CONTINUED) VOCATIONAL REHABILITATION AND EDUCATION Vocational Rehabilitation and Employment Under 38 U.S.C. Chapter 31 Leaves of Absence § 21.348 Leave following completion of a period of training or rehabilitation services. (a) Leave...

2010-07-01

322

38 CFR 21.348 - Leave following completion of a period of training or rehabilitation services.  

Code of Federal Regulations, 2012 CFR

...CONTINUED) VOCATIONAL REHABILITATION AND EDUCATION Vocational Rehabilitation and Employment Under 38 U.S.C. Chapter 31 Leaves of Absence § 21.348 Leave following completion of a period of training or rehabilitation services. (a) Leave...

2012-07-01

323

38 CFR 21.348 - Leave following completion of a period of training or rehabilitation services.  

Code of Federal Regulations, 2013 CFR

...CONTINUED) VOCATIONAL REHABILITATION AND EDUCATION Vocational Rehabilitation and Employment Under 38 U.S.C. Chapter 31 Leaves of Absence § 21.348 Leave following completion of a period of training or rehabilitation services. (a) Leave...

2013-07-01

324

Optical Properties of Leaves: Modelling and Experimental Studies  

Microsoft Academic Search

This paper deals with the interpretation of leaves spectra following an approach based on modelling and laboratory studies.\\u000a First, the leaves structure and principal constituents are described together with the way they interact with light. The effects\\u000a of growth, senescence and environmental factors on the leaf optical properties are summarised. A laboratory study conducted\\u000a on drought stress of maize (Zea

Jean Verdebout; Stephane Jacquemoud; Guido Schmuck

325

Oospore Production of Phytophthora infestans in Potato and Tomato Leaves.  

PubMed

ABSTRACT Fungal, host, and environmental factors affecting sexual reproduction of Phytophthora infestans in planta were studied. Intact and detached leaves were coinoculated with sporangia of various combinations of A(1) and A(2) mating-type isolates; leaves were incubated under various conditions, and oospore production was estimated microscopically within whole, clarified leaflets. Some A(1) + A(2) isolate combinations were more reproductive than others, whereas some potato genotypes better supported oospore formation than others. Tomato usually supported more oospore formation than potato. To induce oospore formation, A(1) and A(2) sporangia were usually mixed at a 1:1 ratio. Ratios of 1:19 to 19:1, however, also allowed abundant production of oospores. Optimal temperatures for sexual sporulation ranged from 8 to 15 degrees C, but oospores also were produced at 23 degrees C. Oogonia developed 5 to 6 days after sporangial coinoculation, and oospores developed after 8 to 10 days. Light had little effect on oospore formation in both tomato and potato leaves provided that initial lesions were established under photoperiodic conditions. Although A1 and A(2) sporangia usually were mixed before inoculation on leaves to obtain oospores, we found that discrete A(1) and A(2) lesions produced on opposite sides of the midvein of tomato leaves also induced oospore formation in the midvein and adjacent tissues. Oospores also formed when the two halves of the leaves were cut and separated at 3 days after sporangial coinoculation, which corresponded with the appearance of late blight lesions. The continuous supply of moisture to infected leaves was essential to oospore production. No oospores or oogonia formed in severely diseased plants kept at 50 to 80% relative humidity. Such plants did allow some oospore formation when kept continuously wet for 2 weeks in plastic boxes or tents. Detached leaves floated on water supported the highest sexual sporulation. Under optimal conditions of wetness and temperature, as many as 100 oospores per mm(2) of tissue were observed. PMID:18945141

Cohen, Y; Farkash, S; Reshit, Z; Baider, A

1997-02-01

326

Chemical analysis of Ginkgo biloba leaves and extracts  

Microsoft Academic Search

The chemical analysis and quality control of Ginkgo leaves and extracts is reviewed. Important constituents present in the medicinally used leaves are the terpene trilactones, i.e., ginkgolides A, B, C, J and bilobalide, many flavonol glycosides, biflavones, proanthocyanidins, alkylphenols, simple phenolic acids, 6-hydroxykynurenic acid, 4-O-methylpyridoxine and polyprenols. In the commercially important Ginkgo extracts some of these compound classes are no

Teris A van Beek

2002-01-01

327

Leaving home in the Netherlands: when and in which housing  

Microsoft Academic Search

Abstract The paper addresses two aspects of leaving the parental home,in the Netherlands: the timing of leaving home in the life course, and the outcome in terms of the first housing situation. We investigate to what extent the timing and the housing outcome,are influenced by the child’s and the parents’ resources, and how they differ between spatial contexts and through

Clara H. Mulder

328

Crystal Macropattern Development in Prunus serotina (Rosaceae, Prunoideae) Leaves  

PubMed Central

• Background and Aims Prunus, subgenus Padus, exhibits two completely different calcium oxalate crystal macropatterns in mature leaves. Foliar macropattern development has been described previously in P. virginiana, representing one version. Prunus serotina, in the group exhibiting the second macropattern, is described here. The goal was to describe developmental details for comparison with P. virginiana, and to extend the sparse current knowledge of crystal macropatterns. • Methods Leaves at various developmental stages were removed from local trees and from herbarium specimens. Early leaf stages and freehand leaf and stem sections were mounted directly in aqueous glycerine; larger leaves were processed whole or in representative pieces in household bleach, dehydrated in alcohol/xylol, and mounted in Permount. Crystals were detected microscopically between crossed polarizers. • Key Results Bud scales have a dense druse population. Druses appear first at the stipule tip and proliferate basipetally but soon stop forming; growing stipules therefore have a declining density of druses. Druses appear at the tip of leaves <1 mm long, then proliferate basipetally in the midrib. Lamina druses appear in the distal marginal teeth of leaves 3 cm long; from here they proliferate basipetally and towards midrib along major veins. In about two-thirds-grown leaves (6–9 cm length) druses are all adaxial to veins of most orders; a shift occurs then to formation of prisms, which appear first abaxial to, then all around, veins. Mature leaves have virtually all prisms encrusting all major veins, more sparsely along smaller minor veins. Late season leaves form epitactic crystals on existing prismatics. • Conclusions The developing and mature macropattern of P. serotina is almost the reverse of the pattern described previously in P. virginiana, and shows that two closely related species can develop radically different modes of crystallization. The few detailed macropattern studies to date reveal striking variations that indicate a new level of organization that must be integrated with the anatomical, physiological and molecular approaches that have been dominant so far. PMID:16513655

LERSTEN, NELS R.; HORNER, HARRY T.

2006-01-01

329

Light absorption by anthocyanins in juvenile, stressed, and senescing leaves.  

PubMed

The optical properties of leaves from five species, Norway maple (Acer platanoides L.), cotoneaster (Cotoneaster alaunica Golite), hazel (Corylus avellana L.), Siberian dogwood (Cornus alba L.), and Virginia creeper (Parthenocissus quinquefolia (L.) Planch.), differing in pigment composition and at different stages of ontogenesis, were studied. Anthocyanin absorption maxima in vivo, as estimated with spectrophotometry of intact anthocyanic versus acyanic leaves and microspectrophotometry of vacuoles in the leaf cross-sections, were found between 537 nm and 542 nm, showing a red shift of 5-20 nm compared with the corresponding maxima in acidic water-methanol extracts. In non-senescent leaves, strong anthocyanin absorption was found between 500 nm and 600 nm (with a 70-80 nm apparent bandwidth). By and large, absorption by anthocyanin in leaves followed a modified form of the Lambert-Beer law, showing a linear trend up to a content of nearly 50 nmol cm(-2), and permitting thereby a non-invasive determination of anthocyanin content. The apparent specific absorption coefficients of anthocyanins at 550 nm showed no substantial dependence on the species. Anthocyanin contribution to total light absorption at 550 nm was followed in maple leaves in the course of autumn senescence. Photoprotection by vacuolar anthocyanins is discussed with special regard to their distribution within a leaf; radiation screening by anthocyanins predominantly localized in the epidermal cells in A. platanoides and C. avellana leaves was also evaluated. PMID:18796701

Merzlyak, Mark N; Chivkunova, Olga B; Solovchenko, Alexei E; Naqvi, K Razi

2008-01-01

330

Photosynthesis in lightfleck areas of homobaric and heterobaric leaves  

PubMed Central

Leaves within a canopy are exposed to a spatially and temporally fluctuating light environment which may cause lateral gradients in leaf internal CO2 concentration and diffusion between shaded and illuminated areas. In previous studies it was hypothesized that lateral CO2 diffusion may support leaf photosynthesis, but the magnitude of this effect is still not well understood. In the present study homobaric leaves of Vicia faba or heterobaric leaves of Glycine max were illuminated with lightflecks of different sizes, mimicking sunflecks. Photosynthetic properties of the lightfleck areas were assessed with combined gas exchange measurements and chlorophyll fluorescence imaging. Lateral diffusion in homobaric leaves with an interconnected intercellular air space stimulated photosynthesis and the effect was largest in small lightfleck areas, in particular when plants were under drought stress. Such effects were not observed in the heterobaric leaves with strongly compartmented intercellular gas spaces. It is concluded that lateral diffusion may significantly contribute to photosynthesis of lightfleck areas of homobaric leaves depending on lightfleck size, lateral diffusivity, and stomatal conductance. Since homobaric leaf structures have been reported for many plant species, it is hypothesized that leaf homobary may have an impact on overall plant performance under conditions with a highly heterogeneous light environment. PMID:20008895

Pieruschka, Roland; Chavarría-Krauser, Andrés; Schurr, Ulrich; Jahnke, Siegfried

2010-01-01

331

Spectra of normal and nutrient-deficient maize leaves  

NASA Technical Reports Server (NTRS)

Reflectance, transmittance and absorptance spectra of normal and six types of nutrient-deficient (N, P, K, S, Mg, and Ca) maize (Zea mays L.) leaves were analyzed at 30 selected wavelengths from 500 to 2600 nm. The analysis of variance showed significant differences in reflectance, transmittance and absorptance in the visible wavelengths among leaf numbers 3, 4, and 5, among the seven treatments, and among the interactions of leaf number and treatments. In the infrared wavelengths only treatments produced significant differences. The chlorophyll content of leaves was reduced in all nutrient-deficient treatments. Percent moisture was increased in S-, Mg-, and N-deficiencies. Polynomial regression analysis of leaf thickness and leaf moisture content showed that these two variables were significantly and directly related. Leaves from the P- and Ca-deficient plants absorbed less energy in the near infrared than the normal plants; S-, Mg-, K-, and N-deficient leaves absorbed more than the normal. Both S- and N-deficient leaves had higher temperatues than normal maize leaves.

Al-Abbas, A. H.; Barr, R.; Hall, J. D.; Crane, F. L.; Baumgardner, M. F.

1973-01-01

332

Nurse manager job satisfaction and intent to leave  

PubMed Central

Background The nurse manager role is critical to staff nurse retention and often the portal to senior nursing leadership, yet little is known about nurse managers' job satisfaction and career plans. The purpose of this study was to describe nurse managers' job satisfaction and intent to leave. Methods An electronic survey was used to collect data from 291 nurse managers working in U.S. hospitals. Findings Seventy percent were satisfied or very satisfied with their jobs and 68% were either likely or very likely to recommend nursing management as a career choice. Seventy-two percent of these nurse managers were also planning to leave their positions in the next five years. The four most common reasons reported for intent to leave included burnout, career change, retirement, and promotion. Burnout was the most common reason cited by the entire sample but the fourth most common reason for leaving cited by those nurse managers who were planning to leave and also satisfied or very satisfied with their positions. Conclusions Recommendations for nursing leaders include evaluating the workload of nurse managers, providing career counseling, and developing succession plans. Additional research is needed to understand the determinants and consequences of nurse manager job satisfaction, intent to leave, and turnover. PMID:24689156

Warshawsky, Nora E.; Havens, Donna S.

2015-01-01

333

Protection by Isoprene against Singlet Oxygen in Leaves  

PubMed Central

Isoprene (2-methyl-1,3-butadiene) protection against effects of singlet oxygen was investigated in Myrtus communis and Rhamnus alaternus. In M. communis, singlet oxygen produced in the leaves by Rose Bengal (RB) led to a 65% decrease in net assimilation rates within 3 h, whereas isoprene emission rates showed either a 30% decrease at ambient CO2 concentrations or a 70% increase under high CO2. In both cases, these changes led to an increase in calculated internal isoprene concentrations. The isoprene protection effect was directly demonstrated by fumigation of young (non-emitting) leaves, treated with RB or bromoxynil (simulating photoinhibition). There was 42% and 29% reduction in the damage to net assimilation compared with non-fumigated leaves for RB or bromoxynil, respectively. In R. alaternus, similar effects of RB on net assimilation were observed, and additional fluorescence measurements showed a significantly smaller decrease in Fv/Fm in isoprene-fumigated young leaves treated with RB (from 0.78 to 0.52), compared with non-fumigated leaves (from 0.77 to 0.27). The internal isoprene concentrations used in this study and possible rate of 1O2 production in leaves indicate that the protective effects observed should be beneficial also under natural conditions. PMID:12011357

Affek, Hagit P.; Yakir, Dan

2002-01-01

334

Metabolism of purine bases, nucleosides and alkaloids in theobromine-forming Theobroma cacao leaves  

Microsoft Academic Search

We examined the purine alkaloid content and purine metabolism in cacao (Theobroma cacao L.) plant leaves at various ages: young small leaves (stage I), developing intermediate size leaves (stage II), fully developed leaves (stage III) from flush shoots, and aged leaves (stage IV) from 1-year-old shoots. The major purine alkaloid in stage I leaves was theobromine (4.5 ?mol g–1 fresh weight),

Yoko Koyama; Yoshihisa Tomoda; Misako Kato; Hiroshi Ashihara

2003-01-01

335

Time & Leave Benefits Summary Higher Education Officer Series Employees Annual Leave Employees accrue annual leave monthly, based on years of service, as set forth below  

E-print Network

Office Human Resources Department. Bereavement Leave Employees may take up to 4 days for the death, or step parent; grand child; mother-in-law; father-in-law; natural, foster, or step brother; natural and effective January 1, 2004, the Domestic Partner of the employee and a child or parent of the Domestic

Rosen, Jay

336

Douglas H. Green Piper & Marbury  

E-print Network

. The purpose of such a suspension would be to avoid expending resources evaluating Part B permits when a mixed for which treatment technology and/or disposal capacity is currently available or becomes available during

337

[FTIR spectroscopic study of broad bean diseased leaves].  

PubMed

In the present paper, broad bean rust, fusarium rhizome rot, broad bean zonate spot, yellow leaf curl virus and normal leaves were studied using Fourier transform infrared spectroscopy combined with chemometrics. The results show that the spectra of samples were similar, only with minor differences in absorption intensity of several peaks. Second derivative analyses show that the significant difference of all samples was in the range of 1200-700 cm(-1). The data in the range of 1 200-700 cm(-1) were selected to evaluate correlation coefficients, hierarchical cluster analysis (HCA) and principal component analysis (PCA). Results showed that the correlation coefficients are larger than 0.928 not only between the healthy leaves, but also between the same diseased leaves. The values between healthy and diseased leaves, and among diseased leaves, are all declined. HCA and PCA yielded about 73.3% and 82.2% accuracy, respectively. This study demonstrated that FTIR techniques might be used to detect crop diseases. PMID:22827057

Li, Zhi-yong; Liu, Gang; Li, Lun; Ou, Quan-hong; Zhao, Xing-xiang; Zhang, Li; Zhou, Xiang-ping; Wang, Lu-xiang

2012-05-01

338

Sucrose transporter1 functions in phloem loading in maize leaves  

PubMed Central

In most plants, sucrose is exported from source leaves to carbon-importing sink tissues to sustain their growth and metabolism. Apoplastic phloem-loading species require sucrose transporters (SUTs) to transport sucrose into the phloem. In many dicot plants, genetic and biochemical evidence has established that SUT1-type proteins function in phloem loading. However, the role of SUT1 in phloem loading in monocot plants is not clear since the rice (Oryza sativa) and sugarcane (Saccharum hybrid) SUT1 orthologues do not appear to function in phloem loading of sucrose. A SUT1 gene was previously cloned from maize (Zea mays) and shown to have expression and biochemical activity consistent with a hypothesized role in phloem loading. To determine the biological function of SUT1 in maize, a sut1 mutant was isolated and characterized. sut1 mutant plants hyperaccumulate carbohydrates in mature leaves and display leaf chlorosis with premature senescence. In addition, sut1 mutants have greatly reduced stature, altered biomass partitioning, delayed flowering, and stunted tassel development. Cold-girdling wild-type leaves to block phloem transport phenocopied the sut1 mutants, supporting a role for maize SUT1 in sucrose export. Furthermore, application of 14C-sucrose to abraded sut1 mutant and wild-type leaves showed that sucrose export was greatly diminished in sut1 mutants compared with wild type. Collectively, these data demonstrate that SUT1 is crucial for efficient phloem loading of sucrose in maize leaves. PMID:19181865

Slewinski, Thomas L.; Meeley, Robert; Braun, David M.

2009-01-01

339

Persistence and metabolism of fipronil in sugarcane leaves and juice.  

PubMed

Fipronil gives effective control of early shoot borer and termites in sugarcane. The persistence and metabolism of fipronil in sugarcane leaves and juice were studied following application of fipronil (Regent 0.3 G) at 75 and 300 g a.i. ha(-1). Samples of sugarcane leaves were collected at various time intervals. Samples of sugarcane juice were collected at harvest. Residues of fipronil and its metabolites were quantified by gas liquid chromatograph. The limit of quantification of fipronil and its metabolites was 0.01 mg kg(-1) for sugarcane leaves and juice. Total residues of fipronil and its metabolites in sugarcane leaves after 7 days of its application at 75 and 300 g a.i. ha(-1) were 0.26 and 0.66 mg kg(-1), respectively. Residues could not be detected after 60 and 90 following fipronil application at either concentration. In sugarcane leaves, fipronil was found to be the main constituent, followed by its metabolites amide, desulfinyl, sulfone and sulfide. Samples of sugarcane juice did not reveal the presence of fipronil or its metabolites following its application at both the dosages at harvest. PMID:24343262

Mandal, Kousik; Singh, Balwinder

2014-02-01

340

A Global Regulation Inducing the Shape of Growing Folded Leaves  

PubMed Central

Shape is one of the important characteristics for the structures observed in living organisms. Whereas biologists have proposed models where the shape is controlled on a molecular level [1], physicists, following Turing [2] and d'Arcy Thomson [3], have developed theories where patterns arise spontaneously [4]. Here, we propose that volume constraints restrict the possible shapes of leaves. Focusing on palmate leaves (with lobes), the central observation is that developing leaves first grow folded inside a bud, limited by the previous and subsequent leaves. We show that the lobe perimeters end at the border of this small volume. This induces a direct relationship between the way it was folded and the final unfolded shape of the leaf. These dependencies can be approximated as simple geometrical relationships that we confirm on both folded embryonic and unfolded mature leaves. We find that independent of their position in the phylogenetic tree, these relationships work for folded species, but do not work for non-folded species. This global regulation for the leaf growth could come from a mechanical steric constraint. Such steric regulation should be more general and considered as a new simple means of global regulation. PMID:19956690

Couturier, Etienne; Courrech du Pont, Sylvain; Douady, Stéphane

2009-01-01

341

[Research on lettuce leaves' moisture prediction based on hyperspectral images].  

PubMed

In order to conduct rational management of watering lettuce, the model of detecting lettuce leaves' moisture was built. First of all, the hyperspectral images of lettuce leaves were acquired and simultaneously the moisture proportions of leaves were measured. Meanwhile, hyperspectral images were analyzed and the characteristic bands of lettuce leaves' moisture were found. Then the images in characteristic bands were processed and the image features of lettuce leaves' moisture were computed. The image features highly relevant to moisture were obtained through correlation analysis. Furthermore, due to the possible correlation among image features, the principal components of the images were extracted by principal components analysis and were used as BP neural network's inputs to establish PCA-ANN model. At the same time, other models were constructed by using BP neural network and traditional MLR (multiple liner regression) method respectively. Prediction examinations of the three models were made based on the same sample data. The experimental results show that the average prediction error of PCA-ANN prediction model of tillering stage reaches 9.323% which is improved compared with BP-ANN and MLR prediction models. PMID:23697146

Sun, Jun; Wu, Xiao-Hong; Zhang, Xiao-Dong; Gao, Hong-Yan

2013-02-01

342

Computational Approach to Seasonal Changes of Living Leaves  

PubMed Central

This paper proposes a computational approach to seasonal changes of living leaves by combining the geometric deformations and textural color changes. The geometric model of a leaf is generated by triangulating the scanned image of a leaf using an optimized mesh. The triangular mesh of the leaf is deformed by the improved mass-spring model, while the deformation is controlled by setting different mass values for the vertices on the leaf model. In order to adaptively control the deformation of different regions in the leaf, the mass values of vertices are set to be in proportion to the pixels' intensities of the corresponding user-specified grayscale mask map. The geometric deformations as well as the textural color changes of a leaf are used to simulate the seasonal changing process of leaves based on Markov chain model with different environmental parameters including temperature, humidness, and time. Experimental results show that the method successfully simulates the seasonal changes of leaves. PMID:23533545

Wu, Dong-Yan

2013-01-01

343

Proteinase Inhibitor-inducing Factor in Plant Leaves  

PubMed Central

Thirty-nine plant species representing 20 families from the four major divisions of plants were surveyed for the presence of proteinase inhibitor-inducing factor activity in leaves or other tissues. Tissue juices were assayed for their capacity to induce accumulation of proteinase inhibitor I in excised tomato (Lycopersico esculentum) leaves. In tissues of only 2 of the 39 species was proteinase inhibitor-inducing factor-like activity not found. The activity was absent in cabbage leaves and celery stalks. Fruiting bodies from one of three fungi genera assayed contained exceptionally large quantities of proteinase inhibitor-inducing factor-like activity. Extracts from Agraricus campestris fruiting bodies contained over 20 times more activity than tomato leaf juice. The survey confirms that substances with proteinase inhibitor-inducing factor-like activity are widespread in the plant kingdom. PMID:16658956

McFarland, Douglas; Ryan, Clarence A.

1974-01-01

344

Densitometric determination of arbutin in cowberry leaves (Vaccinium vitis idaeae).  

PubMed

Densitometry was used for quantitative determination of arbutin (Vaccinium vitis idaeae) in leaves of cowberry collected from region of Suwalszczyzna, Poland. Arbutin was extracted using methanol. Chromatography was performed on glass TLC plates with layers of silica gel. The quantitative densitometric analysis was performed using internal standard solution method. On the base of densitometric analysis it was shown that the band characteristic for absorption maximum of arbutin is placed at lambda(max) = 285 nm. The second absorption band is at lambda = 225 nm. It was stated that contents of arbutin are ca. 35 mg and 47 mg in 1 g of herbs, in cowberry leaves coming from collections in 2005 and 2006 year, respectively. The presented method is accurate, selective, and precise, and can be used for routine quality control analysis and quantitative determination of arbutin in cowberry leaves. PMID:18540157

Pyka, Alina; Bober, Katarzyna; Stolarczyk, Adam

2007-01-01

345

Correlation between loss of turgor and accumulation of abscisic acid in detached leaves  

Microsoft Academic Search

Mature leaves of Phaseolus vulgaris L. (red kidney bean), Xanthium strumarium L. (cocklebur), and Gossypium hirsutum L. (cotton) were used to study accumulation of abscisic acid (ABA) during water stress. The water status of individual, detached leaves was monitored while the leaves slowly wilted, and samples were cut from the leaves as they lost water. The leaf sections were incubated

Margaret Pierce; Klaus Raschke

1980-01-01

346

5 CFR 630.607 - Transfer and recredit of home leave.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Transfer and recredit of home leave. 630.607 Section 630.607 ...CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Home Leave § 630.607 Transfer and recredit of home leave. An employee is entitled to have...

2010-01-01

347

The major phenolic compounds in the leaves of Cyclopia species (honeybush tea)  

Microsoft Academic Search

The phenolic compounds of the leaves of Cyclopia species (tribe Podalyrieae) are of both chemotaxonomic and commercial interest, as the leaves are used to brew a herbal drink known as honeybush tea. Despite the commercial importance of Cyclopia, virtually nothing was known about the chemistry of the leaves prior to the present work. Methanolic extracts from leaves of 22 species

Anna Maria De Nysschen; Ben-Erik Van Wyk; Fanie R. Van Heerden; Anne Lise Schutte

1996-01-01

348

Effect of autumn?olive on the mineral composition of black walnut leaves  

Microsoft Academic Search

Nitrogen concentrations were significantly higher in walnut leaves from trees planted with autumn?olive than in leaves from walnut planted alone, while the reverse was true for potassium. The amount of nitrogen, phosphorus, potassium, calcium, and magnesium based on leaf weight was higher in leaves from walnut trees mixed with autumn?olive than in leaves from walnut planted alone. The differences in

Felix Ponder Jr

1983-01-01

349

Distribution of Salmonella typhimurium in romaine lettuce leaves.  

PubMed

Leafy greens are occasionally involved in outbreaks of enteric pathogens. In order to control the plant contamination it is necessary to understand the factors that influence enteric pathogen-plant interactions. Attachment of Salmonella enterica serovar typhimurium to lettuce leaves has been demonstrated before; however, only limited information is available regarding the localization and distribution of immigrant Salmonella on the leaf surface. To extend our knowledge regarding initial pathogen-leaf interactions, the distribution of green-fluorescent protein-labeled Salmonella typhimurium on artificially contaminated romaine lettuce leaves was analyzed. We demonstrate that attachment of Salmonella to different leaf regions is highly variable; yet a higher attachment level was observed on leaf regions localized close to the petiole (7.7 log CFU g(-1)) compared to surfaces at the far-end region of the leaf blade (6.2 log CFU g(-1)). Attachment to surfaces located at a central leaf region demonstrated intermediate attachment level (7.0 log CFU g(-1)). Salmonella displayed higher affinity toward the abaxial side compared to the adaxial side of the same leaf region. Rarely, Salmonella cells were also visualized underneath stomata within the parenchymal tissue, supporting the notion that this pathogen can also internalize romaine lettuce leaves. Comparison of attachment to leaves of different ages showed that Salmonella displayed higher affinity to older compared to younger leaves (1.5 log). Scanning electron microscopy revealed a more complex topography on the surface of older leaves, as well as on the abaxial side of the examined leaf tissue supporting the notion that a higher attachment level might be correlated with a more composite leaf landscape. Our findings indicate that initial attachment of Salmonella to romaine lettuce leaf depends on multiple plant factors pertaining to the specific localization on the leaf tissue and to the developmental stage of the leaf. PMID:21569943

Kroupitski, Yulia; Pinto, Riky; Belausov, Eduard; Sela, Shlomo

2011-08-01

350

Water is allocated differently to chloroplasts in sun and shade leaves.  

PubMed

Hydrogen-1 nuclear magnetic resonance spectroscopy was used to study water allocation in cell compartments of sun and shade leaves. NMR spectra of Acer platanoides were resolved into two peaks that were assigned to chloroplast and nonchloroplast water. Sun leaves contained 1.7 times more water per unit area of surface than shade leaves, and the water was allocated differently. Chloroplasts in sun leaves contained 17% of the total leaf water versus 47% in shade leaves. Comparing equal leaf surface areas, the chloroplasts in shade leaves contained 60% more water than those in sun leaves. PMID:16665860

McCain, D C; Croxdale, J; Markley, J L

1988-01-01

351

The uptake of elemental iodine vapour by bean leaves  

NASA Astrophysics Data System (ADS)

Deposition of iodine vapour to leaves of phaseolus vulgaris was measured over a range of conditions of humidity, temperature and illumination. Transpiration measurements were used to deduce stomatal opening. The results showed that stomatal resistance controlled iodine absorption at relative humidities below 40 per cent, but that the rate of absorption of iodine increased by an order of magnitude when the relative humidity was raised to 80 per cent, presumably due to cuticular absorption. After exposure to iodine at high humidity, a substantial fraction of the iodine could be washed from the leaves. In Britain, cuticular uptake would probably dominate stomatal uptake of iodine on most occasions.

Garland, J. A.; Cox, L. C.

352

Why Do the Colors of Leaves Change in the Fall?  

NSDL National Science Digital Library

The color change of the leaves on deciduous trees is one of the most striking signals that summer is ending and fall is beginning. What is it that causes this change in color? We all know that leaves contain chlorophyll Â? giving them their green-color but why do they change from green to the palette of colors we see in the fall? In this investigation students determine the pigment molecules that green plants contain and what happens to those molecules as the season progresses.

Mr. William A White (Arsenal Technical High School)

2000-08-01

353

Fungal diversity on fallen leaves of Ficus in northern Thailand* §  

PubMed Central

Fallen leaves of Ficus altissima, F. virens, F. benjamina, F. fistulosa and F. semicordata, were collected in Chiang Mai Province in northern Thailand and examined for fungi. Eighty taxa were identified, comprising 56 anamorphic taxa, 23 ascomycetes and 1 basidiomycete. Common fungal species occurring on five host species with high frequency of occurrence were Beltraniella nilgirica, Lasiodiplodia theobromae, Ophioceras leptosporum, Periconia byssoides and Septonema harknessi. Colletotrichum and Stachybotrys were also common genera. The leaves of different Ficus species supported diverse fungal taxa, and the fungal assemblages on the different hosts showed varying overlap. The fungal diversity of saprobes at the host species level is discussed. PMID:18837113

Wang, Hong-kai; Hyde, Kevin D.; Soytong, Kasem; Lin, Fu-cheng

2008-01-01

354

Triterpenoids and a triterpene glycoside from Schefflera bodinieri leaves  

Microsoft Academic Search

Two novel triterpenoids and a triterpene glycoside have been isolated from the leaves of Schefflera bodinieri. They are 3-oxo-20-demethylisoaleuritolic-14(15)-ene-28,29-dioic acid, 28-O-[?-l-rhamnopyranosyl(1?4)-O-?- d-glucopyranosyl(1?6)-]-O-?-d-glucopyranoside of 3-oxo-20-demethylisoaleuritic-14(15)-ene-28,29-dioic acid and 3?-hydroxyl-20-demethylisoaleuritolic-14(15)-ene-28,30-dioic acid. The known compounds, d-sorbitol, stigmasterol-3-O-?-d-glucose and two trisaccharides, were also isolated from the leaves. The structures were established on the basis of chemical and spectral evidence.

Min Zhu; J. David Phillipson; Pam M. Greengrass; Norman G. Bowery

1996-01-01

355

Free Radical Scavenging Activity of Majorana hortensis leaves  

PubMed Central

Antioxidants are an essential defense mechanism to protect our body against free radical damage. They balance the production of free radicals and detoxify them when in excess. The objective of the study is to determine the free radical scavenging potential of the candidate plant leaves when subjected to a battery of free radical scavenging assays. The different leaf extracts used were aqueous, methanol and chloroform. The results suggest that Majorana hortensis (L.) H. Karst leaves could serve as a potential source of antioxidant and can be used in any preparation for combating free radical mediated damage to the body. PMID:22557436

Palaniswamy, Radha; Padma, P R

2011-01-01

356

Shapes of river networks and leaves: are they statistically similar?  

PubMed Central

The structure of river networks is compared with the vein structure of leaves. The two structures are visually similar at the smaller scales. The statistics of branching and side branching are nearly identical. The branching structure of diffusion-limited aggregation clusters is also similar and can provide an explanation for the structure of river networks. The origin of the self-similar branching and side branching of the vein structure in leaves is not clear but it appears to be an optimal network in terms of transporting nutrients to all parts of the leaf with the least total resistance. PMID:10724463

Pelletier, J D; Turcotte, D L

2000-01-01

357

Shapes of river networks and leaves: are they statistically similar?  

PubMed

The structure of river networks is compared with the vein structure of leaves. The two structures are visually similar at the smaller scales. The statistics of branching and side branching are nearly identical. The branching structure of diffusion-limited aggregation clusters is also similar and can provide an explanation for the structure of river networks. The origin of the self-similar branching and side branching of the vein structure in leaves is not clear but it appears to be an optimal network in terms of transporting nutrients to all parts of the leaf with the least total resistance. PMID:10724463

Pelletier, J D; Turcotte, D L

2000-02-29

358

Maize seedling blight induced by Fusarium verticillioides: accumulation of fumonisin B? in leaves without colonization of the leaves.  

PubMed

Fusarium verticillioides produces fumonisin mycotoxins during the colonization of maize, and fumonisin B? (FB?) production is necessary for manifestation of maize seedling blight disease. The objective of this study was to address FB? mobility and accumulation in seedlings to determine if proximal infection by F. verticillioides is necessary for FB? accumulation. Taking advantage of an aconidial mutant known to have limited capability for seedling infection, tissue and soil samples were analyzed to compare wild-type F. verticillioides against the mutant. Inoculation with either strain caused accumulation of FB? in the first and second leaves, but the mutants were unable to colonize aerial tissues. FB?, FB?, and FB? were detected in the soil and seedling roots, but only FB? was detected in the leaves of any treatment. These data suggest root infection by F. verticillioides is necessary for accumulation of FB? in leaves, but the mechanism for accumulation does not require colonization of the leaf. PMID:24524621

Baldwin, Thomas T; Zitomer, Nicholas C; Mitchell, Trevor R; Zimeri, Anne-Marie; Bacon, Charles W; Riley, Ronald T; Glenn, Anthony E

2014-03-01

359

Physiological, biochemical, and fluorescence parameters of senescing sugar beet leaves in the vegetative phase of growth  

Microsoft Academic Search

The phase of vegetative growth of sugar beet (Beta vulgaris L., single-sprout form) was conditionally subdivided into four periods according to leaf number and size (including already\\u000a withered leaves): (A) 8 ± 1 weeks after seedling emergence (wase) (5–7 leaves); (B) 11 ± 1 wase (10–12 leaves); (C) 14 wase (13–15 leaves); (D) 15 wase (15–18 leaves). It took each

A. K. Romanova; G. A. Semenova; N. S. Novichkova; A. R. Ignat’ev; V. A. Mudrik; B. N. Ivanov

2011-01-01

360

Stomatal development in new leaves is related to the stomatal conductance of mature leaves in poplar (Populus trichocarpaxP. deltoides)  

Microsoft Academic Search

In general, stomatal density (SD) decreases when plants are grown at high CO2 concentrations. Recent studies suggest that signals produced from mature leaves regulate the SD of expanding leaves. To de- termine the underlying driver of these signals in poplar (Populus trichocarpa3P. deltoides) saplings, a cuvette system was used whereby the environment around mature (lower) leaves could be controlled indepen-

Shin-Ichi Miyazawa; Nigel J. Livingston; David H. Turpin

2005-01-01

361

Rapid and Pervasive Occupation of Fallen Mangrove Leaves by a Marine Zoosporic Fungus †  

PubMed Central

Samples of leaves of red mangrove (Rhizophora mangle) were incubated on an agar medium selective for pythiaceous oomycetes. Leaves on trees above the water did not contain oomycetes. Marine oomycetes, principally Phytophthora vesicula, had colonized leaves within 2 h of leaf submergence, probably finding them by chemotaxis. The frequency of occurrence of P. vesicula in submerged leaves reached 100% within 30 h of submergence. By 43 h most, if not all, parts of leaves were occupied, and surface treatment with a biocide indicated that leaves were occupied internally. Frequencies of P. vesicula remained near 100% through about 2 weeks of submergence and then declined to about 60% in older (?4 weeks) leaves. Leaves of white mangrove (Laguncularia racemosa) were also extensively occupied by P. vesicula after falling into the water column, but decaying leaves of turtlegrass (Thalassia testudinum) were not colonized by oomycetes. Ergosterol analysis indicated that the standing crop of living, non-oomycete (ergosterol-containing) fungal mass in submerged red-mangrove leaves did not rise above that which had been present in senescent leaves on the tree; decaying turtlegrass leaves had an ergosterol content that was only about 2% of the maximum concentration detected for red-mangrove leaves. These results suggest that oomycetes are the predominant mycelial eucaryotic saprotrophs of mangrove leaves that fall into the water column and that for turtlegrass leaves which live, die, and decompose under submerged conditions, mycelial eucaryotes make no substantial contribution to decomposition. PMID:16347463

Newell, S. Y.; Miller, J. D.; Fell, J. W.

1987-01-01

362

Turnover and intent to leave among speech pathologists.  

PubMed

Sound, large scale and systematic research into why health professionals want to leave their jobs is needed. This study used psychometrically-sound tools and logistic regression analyses to determine why Australian speech pathologists were intending to leave their jobs or the profession. Based on data from 620 questionnaires, several variables were found to be significantly related to intent to leave. The speech pathologists intending to look for a new job were more likely to be under 34 years of age, and perceive low levels of job security and benefits of the profession. Those intending to leave the profession were more likely to spend greater than half their time at work on administrative duties, have a higher negative affect score, not have children under 18 years of age, and perceive that speech pathology did not offer benefits that met their professional needs. The findings of this study provide the first evidence regarding the reasons for turnover and attrition in the Australian speech pathology workforce, and can inform the development of strategies to retain a skilled and experienced allied health workforce. PMID:20497738

McLaughlin, Emma G H; Adamson, Barbara J; Lincoln, Michelle A; Pallant, Julie F; Cooper, Cary L

2010-05-01

363

ETHICS CODE PROVISIONS FOR THOSE LEAVING STATE SERVICE  

E-print Network

ETHICS CODE PROVISIONS FOR THOSE LEAVING STATE SERVICE The State Code of Ethics contains several should review the following rules and, if necessary, seek guidance from the Office of State Ethics or the Office of Audit, Compliance & Ethics. 1. You may never use confidential information for financial gain

Holsinger, Kent

364

When Fire Ants Move In, Others Leave Elizabeth Pennisi  

E-print Network

ECOLOGY: When Fire Ants Move In, Others Leave Elizabeth Pennisi For Amy Arnett, getting a Ph, collecting ants at 33 sites along the way. They had set out to look at how the food resources for ant lions, insects that prey on ants, changed from north to south along the East Coast. But in the process

Gotelli, Nicholas J.

365

Antioxidant Potential and Oil Composition of Callistemon viminalis Leaves  

PubMed Central

The present study was designed to investigate the antioxidant potential and oil composition of Callistemon viminalis leaves. GC-MS analysis of the n-hexane extract revealed the presence of 40 compounds. Leaves contained appreciable levels of total phenolic contents (0.27–0.85?GAE?mg/g) and total flavonoid contents (2.25–7.96?CE?mg/g). DPPH radical scavenging IC50 and % inhibition of linoleic acid peroxidation were found to be in the ranges of 28.4–56.2??g/ml and 40.1–70.2%, respectively. The haemolytic effect of the plant leaves was found in the range of 1.79–4.95%. The antioxidant activity of extracts was also studied using sunflower oil as an oxidative substrate and found that it stabilized the oil. The correlation between the results of different antioxidant assays and oxidation parameters of oil indicated that leaves' methanolic extract, exhibiting higher TPC and TFC and scavenging power, was also more potent for enhancing the oxidative stability of sunflower oil. PMID:23818824

Zubair, Muhammad; Hassan, Sadia; Rizwan, Komal; Rasool, Nasir; Riaz, Muhammad; Zia-Ul-Haq, M.; De Feo, Vincenzo

2013-01-01

366

Leaving So Soon? Understanding and Predicting Web Search Abandonment Rationales  

E-print Network

Leaving So Soon? Understanding and Predicting Web Search Abandonment Rationales Abdigani Diriye1.diriye@ucl.ac.uk, {ryenw, georgbu, sdumais}@microsoft.com ABSTRACT Users of search engines often abandon their searches. Despite the high frequency of Web search abandonment and its importance to Web search engines, little

Dumais, Susan

367

Department of Human Resources APPLICATION FOR DEFERRED SALARY LEAVE  

E-print Network

Department of Human Resources APPLICATION FOR DEFERRED SALARY LEAVE *Forward to the Director of Human Resources prior to January 31st DEFSAL 08/05 NAME DEPARTMENT ADDRESS PRESENT POSITION NUMBER to Employee Relations, Department of Human Resources, Arts and Administration Building, Memorial University

Oyet, Alwell

368

The Essential Oil of the Leaves of Psidium guajava L  

Microsoft Academic Search

A characterization of the compounds present in the essential oil from the leaves of Psidium guajava L. (a traditional Chinese medicinal plant) has been obtained. ?-Pinene (37.8%) and 1,8-cineole (18.9%) are the major components.

Xiao-duo Ji; Quan-long Pu; H. Martin Garraffo; Lewis K. Pannell

1991-01-01

369

at the National Oceanic and Atmospheric Administration "We must leave  

E-print Network

.kimbrough@noaa.gov) · Lake Sturgeon Health Assessment Contact: Paula Bizot (paula.bizot@noaa.gov) · Great Lakes Sedimentat the National Oceanic and Atmospheric Administration "We must leave the Great Lakes better for the next generation than the condition in which we inherited them." Great Lakes Restoration Initiative

370

Leaving Care: Retrospective Reports by Alumni of Israeli Group Homes  

ERIC Educational Resources Information Center

This study examines the retrospective reports of alumni of Israeli group homes on their experiences of leaving care, taking into account possible gender differences as well as associations with their experiences while in care. The reports of 94 alumni (38 men and 56 women) interviewed by phone revealed major difficulties associated with the…

Schiff, Miriam

2006-01-01

371

Micro Windmills to Recharge Cell Leave a reply  

E-print Network

Micro Windmills to Recharge Cell Phones Leave a reply The Windmill in Action At the University of Texas Arlington, scientists J.C. Chiao and Smitha Rao have developed micro-windmills which recharge Page 1 of 2Micro Windmills to Recharge Cell Phones | MADE 2/3/2014http://themadeblog.com/micro

Chiao, Jung-Chih

372

Transpiration-induced changes in the photosynthetic capacity of leaves  

Microsoft Academic Search

High transpiration rates were found to affect the photosynthetic capacity of Xanthium strumarium L. leaves in a manner analagous to that of low soil water potential. The effect was also looked for and found in Gossypium hirsutum L., Agathis robusta (C. Moore ex Muell.) Bailey, Eucalyptus microcarpa Maiden, Larrea divaricata Cav., the wilty flacca tomato mutant (Lycopersicon esculentum (L.) Mill.)

Thomas D. Sharkey

1984-01-01

373

MODELING EXPANSION OF INDIVIDUAL LEAVES IN THE POTATO CANOPY  

Technology Transfer Automated Retrieval System (TEKTRAN)

A model to simulate expansion of individual leaves in the potato (Solanum tuberosum cv. Kennebec) canopy was developed by modifying an existing growth model. Data for model development and testing were obtained from three soil-plant-atmosphere-research (SPAR) chamber experiments. The first experi...

374

25 CFR 38.12 - Leave system for education personnel.  

Code of Federal Regulations, 2010 CFR

...personnel. (a) Full-time school-term employees...Employees on a full-time school-term contract...incurred on-the-job and not covered by...included under this part. However, whenever...after instructional time. (i) Sick leave...before the first day of student instruction or...

2010-04-01

375

June 3, 2010 Federal Funding Cuts Leave Oceanographers, Spill  

E-print Network

June 3, 2010 Federal Funding Cuts Leave Oceanographers, Spill Responders in Dark By PAUL VOOSEN in tracking the Gulf's unfolding oil disaster. But the money ran out, and the collective blind spot to use satellite snapshots and imperfect models to guess where the oil will travel, dragged by unwatched

Gilbes, Fernando

376

Iridoid glucosides from the leaves and stems of Duranta erecta  

Microsoft Academic Search

From the leaves of Duranta erecta, four new iridoid glucosides, duranterectosides A, B, C and D, were isolated along with durantosides I and II, lamiide, lamiidoside and verbascoside. Duranterectoside A was also isolated from the stems together with durantosides I, II and III, and lamiidoside. The structures of the new compounds were elucidated based on the spectroscopic evidence.

Yoshio Takeda; Youko Morimoto; Takashi Matsumoto; Choei Ogimi; Eiji Hirata; Anki Takushi; Hideaki Otsuka

1995-01-01

377

Iridoid glucosides from the leaves and stems of Duranta erecta.  

PubMed

From the leaves of Duranta erecta, four new iridoid glucosides, duranterectosides A, B, C and D, were isolated along with durantosides I and II, lamiide, lamiidoside and verbascoside. Duranterectoside A was also isolated from the stems together with durantosides I, II and III, and lamiidoside. The structures of the new compounds were elucidated based on the spectroscopic evidence. PMID:7626266

Takeda, Y; Morimoto, Y; Matsumoto, T; Ogimi, C; Hirata, E; Takushi, A; Otsuka, H

1995-07-01

378

Neolignans from the Leaves of Casearia sylvestris Swartz  

Technology Transfer Automated Retrieval System (TEKTRAN)

Six new neolignans, casearialignans A-F (1-6) and one known lignan syringaresinol-ß-D-glucoside were isolated from the leaves of Casearia sylvestris. Their structures were determined on the basis of 1D and 2 D NMR and high resolution ESI-MS spectroscopic analyses. The relative and absolute configura...

379

COLORADO SCHOOL OF MINES LEAVE SHARING BANK PROGRAM  

E-print Network

-altering catastrophic events or emergencies, such as wildfires, floods, tornados, other natural disasters, murder, and illness/injury covered by short-term and long-term disability (except for the waiting period), PERA and sick leave. The bank may also be available to employees who are directly affected by life

380

Academic radiology: the reasons to stay or leave 1  

Microsoft Academic Search

Rationale and Objectives. To find major reasons why junior academic radiologists leave academia for private practice and to suggest future changes to motivate them to stay.Materials and Methods. 2000 surveys were sent to every tenth member of the Radiological Society of North America (RSNA) who completed training within the past decade. Those in academic institutions and those who left within

Mihra S Taljanovic; Tim B Hunter; Elizabeth A Krupinski; Jennifer N Alcala; Kimberly A Fitzpatrick; Theron W Ovitt

2003-01-01

381

Carbon Dreaming: getting to know hummers, tropical leaves  

E-print Network

Carbon Dreaming: getting to know hummers, tropical leaves and power plants Kevin Robert Gurney (CSU Cotton Honorary Stove! #12;The Global Carbon Cycle (pre-industrial) Atmosphere! 500! Units: billion tons Global Carbon Cycle Atmosphere! 500! Units: billion tons of C = 1 Gt C Ocean! 38,000! ~90/yr! ~90/yr

Collett Jr., Jeffrey L.

382

Who Is No Child Left Behind Leaving Behind?  

Microsoft Academic Search

More than six years after the election of our current president, the nation is analyzing the effects of the No Child Left Behind (NCLB) federal legislation. Educators are discovering that the plan is flawed, developmentally inappropriate, ill funded, and leaving more students, teachers, and schools behind than ever before. In this article, the author offers a brief history of educational

Theoni Soublis Smyth

2008-01-01

383

Who Is No Child Left Behind Leaving Behind?  

ERIC Educational Resources Information Center

More than six years after the election of our current president, the nation is analyzing the effects of the No Child Left Behind (NCLB) federal legislation. Educators are discovering that the plan is flawed, developmentally inappropriate, ill funded, and leaving more students, teachers, and schools behind than ever before. In this article, the…

Smyth, Theoni Soublis

2008-01-01

384

A Statewide Analysis of RNs' Intention To Leave Their Position.  

ERIC Educational Resources Information Center

Secondary analysis of registered nurse work force data from Vermont (n=4,418, 85% response) identified predictors of intention to leave current position. Differences in intention vary by educational attainment, hours worked, gender, practice role, and practice activity. Improving retention will require increased attention to compensation,…

Rambur, Betty; Palumbo, Mary Val; McIntosh, Barbara; Mongeon, Joan

2003-01-01

385

Isolation and Characterization of Phosphatidyl Choline from Spinach Leaves.  

ERIC Educational Resources Information Center

This inexpensive but informative experiment for undergraduate biochemistry students involves isolating phosphatidyl choline from spinach leaves. Emphasis is on introducing students to techniques of lipid extraction, separation of lipids, identification using thin layer chromatography, and identification of fatty acids. Three periods of three hours…

Devor, Kenneth A.

1979-01-01

386

In vitro antiprotozoal activity of the leaves of Artemisia ludoviciana  

Microsoft Academic Search

The inhabitants of Northeast of Mexico use an infusion of leaves from Artemisia ludoviciana as an antidiarrheal remedy. The aqueous, methanol, acetone and hexane leaf extracts from mature plants were found to be active in vitro against the parasitic protozoa Entamoeba histolytica and Giardia lamblia.

Salvador Said Fernández; Monica Celina Ramos Guerra; Benito David Mata Cárdenas; Javier Vargas Villarreal; Licet Villarreal Treviño

2005-01-01

387

In vitro antiprotozoal activity of the leaves of Artemisia ludoviciana.  

PubMed

The inhabitants of Northeast of Mexico use an infusion of leaves from Artemisia ludoviciana as an antidiarrheal remedy. The aqueous, methanol, acetone and hexane leaf extracts from mature plants were found to be active in vitro against the parasitic protozoa Entamoeba histolytica and Giardia lamblia. PMID:15975735

Said Fernández, Salvador; Ramos Guerra, Monica Celina; Mata Cárdenas, Benito David; Vargas Villarreal, Javier; Villarreal Treviño, Licet

2005-07-01

388

Rutin and Luteolin from Spearmint (Mentha spicata L.) Leaves  

Microsoft Academic Search

In this study, supercritical carbon dioxide (SC-CO ) extraction conditions were optimized for the 2 simultaneous separation of four bioactive flavonoids (catechin, CA; epicatechin, EP; rutin, RU; luteolin, LU) contained in spearmint (Mentha spicata L.) leaves. SC-CO extraction parameters such as pressure, temperature 2 and dynamic extraction time were optimized by Complete Randomize Design (CRD) full factorial. The optimum condition

M. Bimakr; R. A. Rahman; F. S. Taip; L. T. Chuan; A. Ganjloo; J. Selamat; A. Hamid

389

Adaptive Significance of Evergreen vs. Deciduous Leaves: Solving the Triple  

E-print Network

evergreens, deciduous trees, optimality models, leaf longevity, phenology Author´s address Dept of Botany imagery (DeFries et al. 2000), evergreen broad-leaved trees dominate tropical rain forests and cloud, boreal forests, 2) deciduous larch in many nutrient-poor peatlands, and 3) evergreen leaf

Givnish, Thomas J.

390

Lock Your Computer Screen Before Leaving Your Desk  

E-print Network

Lock Your Computer Screen Before Leaving Your Desk Locking your computer's screen is an easy and effective step to take to protect the information on your computer system while it's unattended. Create Virus Protection Computers are infected with a virus more often than most people. Make sure antivirus

California at Santa Barbara, University of

391

Methyl Jasmonate Induces Papain Inhibitor(s) in Tomato Leaves.  

PubMed Central

Leaves of 18- to 24-d-old tomato (Lycopersicon esculentum) plants exposed to gaseous methyl jasmonate (MJ) for 24 h at 30[deg]C in continuous light contained high levels of soluble protein that inhibited papain. Chromatographic analysis demonstrated that the active protein had a molecular mass of 80 to 90 kD. Induction of papain inhibitor was directly related to the concentration of air-borne MJ up to a maximum of 0.1 [mu]L MJ per treatment and depended on the duration of exposure up to 18 h. Inhibitor activity in plants treated for less than 18 h increased with time after treatment. Levels remained constant for up to 4 d after treatment, after which time activity decreased. The youngest leaf, leaf 5, consistently lost activity at a faster rate than older, lower leaves. Inhibitor concentration in all leaves was reduced to minimum levels by 11 d after MJ treatment, but did not return to control levels. Treatment with MJ in the dark did induce inhibitor activity, but at a significantly lower rate. Polyclonal antibodies raised to purified potato tuber skin cysteine proteinase inhibitors (CPI) cross-reacted with the tomato inhibitor, suggesting that the tomato papain inhibitor and the potato CPI are closely related. No papain inhibitor activity was observed in extracts from wounded tomato leaves, nor was there any immunoreactivity with antibodies raised to potato tuber skin CPI. PMID:12232028

Bolter, C. J.

1993-01-01

392

Spectral characteristics of normal and nutrient-deficient maize leaves  

NASA Technical Reports Server (NTRS)

Reflectance, transmittance and absorbance spectra of normal and six types of mineral-deficient (N,P,K,S,Mg and Ca) maize (Zea mays L.) leaves were analyzed at 30 selected wavelengths along the electromagnetic spectrum from 500 to 2600 nm. Chlorophyll content and percent leaf moisture were also determined. Leaf thermograms were obtained for normal, N- and S- deficient leaves. The results of the analysis of variance showed significant differences in reflectance, transmittance and absorbance in the visible wavelengths among leaf numbers 3, 4, and 5, among the seven nutrient treatments, and among the interactions of leaves and treatments. In the reflective infrared wavelengths only treatments produced significant differences. The chlorophyll content of leaves was reduced in all deficiencies in comparison to controls. Percent moisture was increased in S-, Mg- and N- deficiencies. Positive correlation (r = 0.707) between moisture content and percent absorption at both 1450 and 1930 nm were obtained. Polynomial regression analysis of leaf thickness and leaf moisture content showed that these two variables were significantly and directly related (r = 0.894).

Al-Abbas, A. H.; Barr, R.; Hall, J. D.; Crane, F. L.; Baumgardner, M. F.

1972-01-01

393

Modeling Carbon Export Out of Mature Peach Leaves  

Microsoft Academic Search

The characteristics of sorbitol and sucrose export out of mature leaves in seedlings of peach (frunus persica 1. Batsch cv CF 305) were investigated by simulating carbon fluxes through the leaf. Three treatments were employed: a control treatment and two treatments modifying leaf export, the latter using either shading or girdling. Photosynthesis and \\

Annick Moing; Abraham Escobar-Cutierrez; Jean Pierre Caudillère

394

46 CFR 502.68 - Motion for leave to intervene.  

Code of Federal Regulations, 2013 CFR

...intervene. (a) Filing. A motion for leave to intervene may...this chapter. (2) The motion must: (i) Comply with...intervention, and address the grounds for intervention set forth...part. (3) A response to a motion to intervene must be...

2013-10-01

395

46 CFR 502.68 - Motion for leave to intervene.  

...intervene. (a) Filing. A motion for leave to intervene may...this chapter. (2) The motion must: (i) Comply with...intervention, and address the grounds for intervention set forth...part. (3) A response to a motion to intervene must be...

2014-10-01

396

Nutritive evaluation of some Acacia tree leaves from Kenya  

Microsoft Academic Search

A study was conducted to evaluate the nutritive potential value of six species of acacia tree leaves: Acacia brevispica, nubica, tortilis, seyal, nilotica, and mellifera from Kenya. A wide variability in chemical composition, polyphenolics and gas production and in situ dry matter (DM) degradability was recorded. Crude protein (CP) content ranged from 134 to 213g\\/kg DM. The content of neutral

S. A. Abdulrazak; T. Fujihara; J. K. Ondiek; E. R. Ørskov

2000-01-01

397

Cytology of infection of apple leaves by Diplocarpon mali  

Technology Transfer Automated Retrieval System (TEKTRAN)

Diplocarpon mali, the causal agent of Marssonina leaf blotch of apple, causes severe defoliation during the growing season. Little information is available on the mode of infection and infection process. In this study, the infection strategies of D. mali in apple leaves were investigated using fluor...

398

Policy in Action: New Jersey's Family Leave Insurance  

E-print Network

Policy in Action: New Jersey's Family Leave Insurance Program at Age Three KAREN WHITE LINDA HOUSER ELIZABETH NISBET Center for Women and Work Rutgers, the State University of New Jersey School of Management at Rutgers, The State University of New Jersey. CWW is also affiliated with the internationally

399

Acylated anthocyanins from leaves of the water lily, Nymphaéa × marliacea  

Microsoft Academic Search

Three anthocyanins have been isolated from the leaves of the water lily, Nymphaéa × marliacea. Even though the lability of the two major anthocyanins was high, especially the linkage between the acetic acid and the galactose moieties, it was possible by means of homo- and heteronuclear two-dimensional NMR techniques and electrospray mass spectrometry to give the full structures of the

Torgils Fossen; Øyvind M. Andersen

1997-01-01

400

Students Matter in School Reform: Leaving Fingerprints and Becoming Leaders  

ERIC Educational Resources Information Center

Our examination of three schools demonstrates how students can be involved in school reform by giving input about problems, helping design the reform, and sharing implementation responsibilities with adult leaders. Their involvement affects both the reform--as students leave their fingerprints on it--and the students themselves, who show signs of…

Osberg, Jerusha; Pope, Denise; Galloway, Mollie

2006-01-01

401

Antioxidant capacity of Adansonia digitata fruit pulp and leaves  

Microsoft Academic Search

In the recent years, in the attempt to counteract the detrimental effects of oxidative damages is always more convincing the strategy of implementing the diet with antioxidants nutrients, especially deriving from natural sources. Etnobotanical studies have confirmed the high content of antioxidant vitamins in Adansonia digitata fruit constituents and leaves. Baobab fruit pulp can be considered a much valuable source

Silvia Vertuani; Elena Braccioli; Valentina Buzzoni; Stefano Manfredini

2002-01-01

402

Typical ADHD Care Leaves Room for Improvement, Study Finds  

MedlinePLUS

... features on this page, please enable JavaScript. Typical ADHD Care Leaves Room for Improvement, Study Finds Many ... 2015) Monday, November 3, 2014 Related MedlinePlus Pages Attention Deficit Hyperactivity Disorder Children's Health Talking With Your Doctor MONDAY, Nov. ...

403

Adolescents Leaving Parental Home: Psychosocial Correlates and Implications for Conservation  

E-print Network

correspondence to Li An, Department of Fisheries and Wildlife, Michigan State University, 13 Natural Resources- ever, the psychological causes and effects of leaving one's parental home, and especially with observable conflicts between development and conversation goals, provides us an ex- cellent site to address

An, Li

404

Quantitative HPLC analysis of cardiac glycosides in Digitalis purpurea leaves.  

PubMed

An analytical method for the determination of cardiac glycosides in Digitalis purpurea leaves by hplc was developed. Quantitation was carried out by the incorporation of lanatoside A as an internal standard. The present method is sufficiently precise and relatively simple. PMID:7673934

Ikeda, Y; Fujii, Y; Nakaya, I; Yamazaki, M

1995-06-01

405

REQUEST FOR LEAVE NAME__________________________College of Charleston ID# (CWID#)________________  

E-print Network

. Family Sick Leave/Medical Appt.* 9. Death in Family __three or less days __over three days Relation the employee or the spouse. Death in the Immediate Family ­ up to three consecutive workdays with pay for death of spouse, parents, grandparents, great-grandparents, brothers, sisters, children, grandchildren and great

Kasman, Alex

406

Antiinflammatory property of the leaves of Gongronema latifolium.  

PubMed

An aqueous extract of the dried leaves of Gongronema latifolium was studied for its antiinflammatory activity. The extract significantly (p < 0.05) inhibited carrageenan-induced rat paw oedema, carrageen-induced leucocyte migration in rats and dye leakage induced by intraperitoneal injection of acetic acid in mice. These results demonstrate the antiinflammatory property of G. latifolium. PMID:11933146

Morebise, Olugbenga; Fafunso, Michael A; Makinde, J Modupe; Olajide, Olumayokun A; Awe, E O

2002-03-01

407

CONTROL OF POWDERY MILDEW ON LEAVES AND STEMS OF GOOSEBERRY  

Technology Transfer Automated Retrieval System (TEKTRAN)

Powdery mildew [Sphaerotheca mors-uvae (Scw.) Berk] severely infects young shoots and leaves of gooseberry (Ribes uva-crispa L.) in the Pacific Northwest. Less environmentally damaging control measures are being sought as alternatives to sulfur or de-methylation inhibiting fungicides. This study exa...

408

Expedition Five crew is ready to leave KSC for Houston  

NASA Technical Reports Server (NTRS)

KENNEDY SPACE CENTER, FLA. -- The Expedition Five crew are ready to leave KSC for Houston. From left are Science Officer Peggy Whitson, Commander Valery Korzun and Flight Engineer Sergei Treschev. The three returned to Earth on Endeavour Dec. 7, with the STS-113 crew, after six months on the International Space Station.

2002-01-01

409

Wet fractionation for improved utilization of alfalfa leaves  

Technology Transfer Automated Retrieval System (TEKTRAN)

Utilization of alfalfa could be greatly improved if protein-rich leaves were efficiently separated and preserved from fibrous stems. This work envisions a new harvest scheme combining three processes: mechanical leaf separation, dewatering, and fermentation. Gross plant fractionation is accomplished...

410

The effects of polyphenols in olive leaves on platelet function  

Microsoft Academic Search

IntroductionThe phenolic compounds of olive leaves and olive oils in the Mediterranean diet have been associated with a reduced incidence of heart disease. Accordingly, antioxidant-rich diets may prevent the deleterious effects of oxidative metabolism by scavenging free radicals, thus inhibiting oxidation and delaying atherosclerosis. The process involves phospholipase C activation and arachidonic acid metabolism, and is thought to reduce hydrogen

Indu Singh; Michelle Mok; Anne-Marie Christensen; Alan H. Turner; John A. Hawley

2008-01-01

411

Growth and regeneration of waxes on the leaves of Eucalyptus  

Microsoft Academic Search

The relationships of wax morphology to wax chemistry and the effects of light intensity on wax development were investigated using rubbing techniques to produce nearly wax free cuticular surfaces. Wax regeneration took place rapidly on leaves which were in their exponential stage of expansion, but only slowly on those that had fully expanded. The pattern of wax development suggested that

N. D. Hallam

1970-01-01

412

Research Papers Leaf Processing by Wild Chimpanzees: Physically Defended Leaves  

E-print Network

Research Papers Leaf Processing by Wild Chimpanzees: Physically Defended Leaves Reveal Complex Andrews, Fife, Scotland Abstract The manual processing of eight species of leaf was investigated in the M-group chimpanzees of Mahale Mountains National Park, Tanzania. Leaf species varied in the extent to which physical

413

Volatile Constituents of the Leaves of Ocimum sanctum L  

Microsoft Academic Search

Analysis of the volatiles isolated from the leaves of Ocimum sanctum L., Lamiaceae, by capillary GC and GC\\/MS resulted in the identification of 25 components comprising 98.7% of the total oil. Eugenol (53.4%), ?-caryophyllene (31.7%) and ?-elemene (6.2%) were the major components found.

P. M. Raju; Mohamed Ali; Arturo Velasco-Negueruela; María José Pérez-Alonso

1999-01-01

414

202 Music PROFESSORS Preston, Rasmussen (Chair), Serghi (on leave Fall  

E-print Network

202 · Music Music PROFESSORS Preston, Rasmussen (Chair), Serghi (on leave Fall 2012). ASSOCIATE Gilman.VISITINGLECTURERMauthe,DIRECTOROFAPPLIED MUSIC Zwelling. ARTS LIBRARIAN DeLaurenti. VISITING AS. The Department of Music is committed to teaching the discipline of music through its interrelated subdisciplines

Lewis, Robert Michael

415

Photosynthesis in Plants with Non-Green Leaves  

ERIC Educational Resources Information Center

Enquiry based learning is an important tool in science teaching. Students of Class XI (16-17 years old) were asked to hypothesise on the role of different pigments found in plants with non-green leaves. The majority hypothesised that these plants were devoid of chlorophylls and some other pigments performed the function of photosynthesis. Their…

Vartak, Rehka

2006-01-01

416

Photosynthesis and nitrogen relationships in leaves of C 3 plants  

Microsoft Academic Search

The photosynthetic capacity of leaves is related to the nitrogen content primarily bacause the proteins of the Calvin cycle and thylakoids represent the majority of leaf nitrogen. To a first approximation, thylakoid nitrogen is proportional to the chlorophyll content (50 mol thylakoid N mol-1 Chl). Within species there are strong linear relationships between nitrogen and both RuBP carboxylase and chlorophyll.

John R. Evans

1989-01-01

417

The evolution, morphology, and development of fern leaves.  

PubMed

Leaves are lateral determinate structures formed in a predictable sequence (phyllotaxy) on the flanks of an indeterminate shoot apical meristem. The origin and evolution of leaves in vascular plants has been widely debated. Being the main conspicuous organ of nearly all vascular plants and often easy to recognize as such, it seems surprising that leaves have had multiple origins. For decades, morphologists, anatomists, paleobotanists, and systematists have contributed data to this debate. More recently, molecular genetic studies have provided insight into leaf evolution and development mainly within angiosperms and, to a lesser extent, lycophytes. There has been recent interest in extending leaf evolutionary developmental studies to other species and lineages, particularly in lycophytes and ferns. Therefore, a review of fern leaf morphology, evolution and development is timely. Here we discuss the theories of leaf evolution in ferns, morphology, and diversity of fern leaves, and experimental results of fern leaf development. We summarize what is known about the molecular genetics of fern leaf development and what future studies might tell us about the evolution of fern leaf development. PMID:24027574

Vasco, Alejandra; Moran, Robbin C; Ambrose, Barbara A

2013-01-01

418

Leaving Education: The Agony and the Ecstasy of Changing Careers.  

ERIC Educational Resources Information Center

A description is given of a workshop format that is being successfully used to motivate and guide teachers who are changing careers. Reasons cited for teachers leaving the profession include a heavily supplied market with reduced demand, economic stagnation and noncompetitive salaries, and job burnout. The workshop is designed to promote the…

Stone, Christopher I.

419

Functional transient genetic transformation of Arabidopsis leaves by biolistic bombardment  

E-print Network

with genetically modified Arabidopsis plants. Floral dip, however, is designed for the production of transgenicFunctional transient genetic transformation of Arabidopsis leaves by biolistic bombardment Shoko. Arabidopsis thaliana is the most widely used model organism for plant biology research due to the availability

Citovsky, Vitaly

420

Crystal Macropattern Development in Prunus serotina (Rosaceae, Prunoideae) Leaves  

Microsoft Academic Search

Background and Aims Prunus, subgenus Padus, exhibits two completely different calcium oxalate crystal macropatterns in mature leaves. Foliar macropattern development has been described previously in P. virginiana, representing one version. Prunus serotina, in the group exhibiting the second macropattern, is described here. The goal was to describe developmental details for comparison with P. virginiana, and to extend the sparse current

NELS R. LERSTEN; HARRY T. HORNER

2006-01-01

421

New prenylflavones from the leaves of Epimedium saggitatum.  

PubMed

Five new prenylflavones, yinyanghuo A (1), yinyanghuo B (2), yinyanghuo C (3), yinyanghuo D (4), and yinyanghuo E (5), along with six known flavonoids, chrysoeriol, quercetin, apigenin, apigenin 7,4'-dimethyl ether, kaempferol, and luteolin, were isolated from the leaves of Epimedium sagittatum. Their structures were determined from spectral analysis. Compounds 1 and 2 showed significant antiplatelet induced by arachidonic acid. PMID:8699184

Chen, C C; Huang, Y L; Sun, C M; Shen, C C

1996-04-01

422

Indole alkaloids from leaves and twigs of Rauvolfia verticillata.  

PubMed

Seven new indole alkaloids, rauverines A-G (1-7), and 19 known indole alkaloids were isolated from the leaves and twigs of Rauvolfia verticillata. All compounds showed no cytotoxicity against five human cancer cell lines, human myeloid leukemia (HL-60), hepatocellular carcinoma (SMMC-7721), lung cancer (A-549), breast cancer (MCF-7), and colon cancer (SW480) cells. PMID:24266393

Zhang, Bing-Jie; Peng, Lei; Wu, Zhi-Kun; Bao, Mei-Fen; Liu, Ya-Ping; Cheng, Gui-Guang; Luo, Xiao-Dong; Cai, Xiang-Hai

2013-01-01

423

Optimal vein density in artificial and real leaves  

PubMed Central

The long evolution of vascular plants has resulted in a tremendous variety of natural networks responsible for the evaporatively driven transport of water. Nevertheless, little is known about the physical principles that constrain vascular architecture. Inspired by plant leaves, we used microfluidic devices consisting of simple parallel channel networks in a polymeric material layer, permeable to water, to study the mechanisms of and the limits to evaporation-driven flow. We show that the flow rate through our biomimetic leaves increases linearly with channel density (1/d) until the distance between channels (d) is comparable with the thickness of the polymer layer (?), above which the flow rate saturates. A comparison with the plant vascular networks shows that the same optimization criterion can be used to describe the placement of veins in leaves. These scaling relations for evaporatively driven flow through simple networks reveal basic design principles for the engineering of evaporation–permeation-driven devices, and highlight the role of physical constraints on the biological design of leaves. PMID:18599446

Noblin, X.; Mahadevan, L.; Coomaraswamy, I. A.; Weitz, D. A.; Holbrook, N. M.; Zwieniecki, M. A.

2008-01-01

424

Einstein's Tea Leaves and Pressure Systems in the Atmosphere  

ERIC Educational Resources Information Center

Tea leaves gather in the center of the cup when the tea is stirred. In 1926 Einstein explained the phenomenon in terms of a secondary, rim-to-center circulation caused by the fluid rubbing against the bottom of the cup. This explanation can be connected to air movement in atmospheric pressure systems to explore, for example, why low-pressure…

Tandon, Amit; Marshall, John

2010-01-01

425

LEAVES AND THE EFFECTS OF ELEVATED CARBON DIOXIDE LEVELS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Since the onset of the Industrial Revolution, the burning of fossil fuel and the clearing of land has led to dramatic rises in the concentration of CO2 in the atmosphere. Leaves concentrate highly dilute CO2 from the atmosphere and transform organic carbon compounds into useful forms (food and fibe...

426

ASYMMETRIC LEAVES1 regulates abscission zone placement in Arabidopsis flowers  

PubMed Central

Background The sepals, petals and stamens of Arabidopsis flowers detach via abscission zones formed at their boundaries with the underlying receptacle. The ASYMMETRIC LEAVES1 (AS1) MYB transcription factor plays a critical role in setting boundaries between newly formed leaf primordia and the shoot meristem. By repressing expression of a set of KNOTTED1-LIKE HOMEODOMAIN (KNOX) genes from developing leaf primordia, AS1 and its partner ASYMMETRIC LEAVES2 allow the patterning and differentiation of leaves to proceed. Here we show a unique role for AS1 in establishing the positions of the sepal and petal abscission zones in Arabidopsis flowers. Results In as1 mutant flowers, the sepal abscission zones are displaced into inverted V-shaped positions, leaving behind triangular stubs of tissue when the organs abscise. Movement of the petal abscission zones is also apparent. Abscission of the medial sepals is delayed in as1 flowers; loss of chlorophyll in the senescing sepals contrasts with proximal zones that remain green. AS1 has previously been shown to restrict expression of the KNOX gene, BREVIPEDICELLUS (BP), from the sepals. We show here that loss of BP activity in as1 flowers is sufficient to restore the positions of the sepal and petal abscission zones, the sepal-receptacle boundary of the medial sepals and the timing of their abscission. Conclusions Our results indicate that AS1 activity is critical for the proper placement of the floral organ abscission zones, and influences the timing of organ shedding. PMID:25038814

2014-01-01

427

5 CFR 550.1207 - Recrediting annual leave.  

Code of Federal Regulations, 2010 CFR

... PAY ADMINISTRATION (GENERAL) Lump-Sum Payment for Accumulated and Accrued Annual...reemployment and the expiration of the lump-sum period. The recredited annual leave...reemployment and the expiration of the lump-sum period. (2) When an employee...

2010-01-01

428

Leaving home in the Netherlands: Timing and first housing  

Microsoft Academic Search

Successive birth cohorts have left the parentalhome at an accelerating pace in the earlypost-war decades in the Netherlands. A secondtrend, starting later but lasting longer, isthat people increasingly leave the parentalhome to live alone. Both trends have hadimplications for the housing market as theycontributed to the continuation of the housingshortage and generated a shift in the type ofaccommodation in which

Clara H. Mulder; Pieter Hooimeijer

2002-01-01

429

Voices from the Darkness: A House of Leaves Experience  

Microsoft Academic Search

House of Leaves is both a love letter to the written word and a demonstration of its inadequacies, a cautionary tale, a horror story, a romance, a bildungsroman, an eloquent mockery of literary criticism, and much else besides. It incorporates postmodern poly-vocal framing techniques, which are sort of a literary version of Russian nesting dolls, if the dolls all talked

Waltman Melanie

2009-01-01

430

PHYTOCHEMICAL INVESTIGATION ON THE LEAVES OF DODONAEA VISCOSA var. ANGUSTIFOLIA.  

E-print Network

??The petroleum ether extract of the leaves of Dodonaea viscosa var. angustifolia afforded a diterpene 5-(2-(furan-3-yl)ethyl)-3,4,4a,5,6,7,8,8a-octahydro-8 hydroxy-5,6,8a-trimethylnaphthalene-1-carboxylic acid (compound Dc-8B) whereas the chloroform extract gave… (more)

Dessalegn, Bekele

2009-01-01

431

When the Leader Leaves: Sustaining Success at Romero High School  

ERIC Educational Resources Information Center

This case study asks readers to consider what leadership actions might help to sustain success for immigrant students in a small urban high school when the leader leaves. Principal Michael Perez, the founding principal of Romero High School, has been recruited to become the superintendent of a first-ring suburban district with rapidly changing…

Johnson, Lauri; Sillman, Kathryn

2012-01-01

432

Incidence of naturally internalized bacteria in lettuce leaves.  

PubMed

Lettuce is the fresh leafy vegetable most frequently involved in foodborne disease outbreaks. Human bacterial pathogens may be experimentally internalized into lettuce plants, but the occurrence of natural microflora inside lettuce leaves has not been elucidated. To characterize the endophytic microorganism residing in commercial lettuce leaves, two separate studies were conducted. First, a total of 30 and 25 heads of romaine and red leaf lettuce, respectively, served as the source of individual leaves which were surface sterilized, stomached, enriched in BHI broth for 24h and plated onto BHI agar for non-selective isolation of internalized microorganism. In a separate survey, 80 heads of each of the two types of lettuce were similarly processed, except that GN broth and MacConkey agar (MCA) were used for isolation of Gram negative bacteria. Thirty-eight out of 100 leaves were positive for internalized microorganisms, and Bacillus, Pseudomonas and Pantoea were the genera most frequently found in both types of lettuce. Members of the genus Erwinia were isolated from romaine lettuce only. In the second study, 21 and 60% of romaine and red leaf lettuce heads, respectively, had internalized bacteria capable of growing on MCA. Among the Gram negative strains, Pseudomonas and Pantoea genera were most frequently isolated. Enterobacter isolates were obtained from three red leaf samples. In summary, spore-forming bacteria and traditional epiphytic bacterial genera were frequently detected in surface-sterilized commercial lettuce leaves. Despite the common occurrence of internalized bacteria, only Enterobacter was related to Escherichia coli O157:H7 and Salmonella. PMID:23454817

Hou, Zhe; Fink, Ryan C; Radtke, Christie; Sadowsky, Michael J; Diez-Gonzalez, Francisco

2013-04-01

433

29 CFR 825.310 - Certification for leave taken to care for a covered servicemember (military caregiver leave).  

Code of Federal Regulations, 2010 CFR

...DEPARTMENT OF LABOR OTHER LAWS THE FAMILY AND MEDICAL LEAVE...servicemember to have such periodic care and an estimate of the...servicemember to have such periodic care, which can include assisting...frequency and duration of the periodic care. (c) Required...

2010-07-01

434

29 CFR 825.310 - Certification for leave taken to care for a covered servicemember (military caregiver leave).  

Code of Federal Regulations, 2012 CFR

...DEPARTMENT OF LABOR OTHER LAWS THE FAMILY AND MEDICAL LEAVE...servicemember to have such periodic care and an estimate of the...servicemember to have such periodic care, which can include assisting...frequency and duration of the periodic care. (c) Required...

2012-07-01

435

29 CFR 825.310 - Certification for leave taken to care for a covered servicemember (military caregiver leave).  

Code of Federal Regulations, 2011 CFR

...DEPARTMENT OF LABOR OTHER LAWS THE FAMILY AND MEDICAL LEAVE...servicemember to have such periodic care and an estimate of the...servicemember to have such periodic care, which can include assisting...frequency and duration of the periodic care. (c) Required...

2011-07-01

436

Why Leaves Turn Red in Autumn. The Role of Anthocyanins in Senescing Leaves of Red-Osier Dogwood  

Microsoft Academic Search

Why the leaves of many woody species accumulate anthocyanins prior to being shed has long puzzled biologists because it is unclear what effects anthocyanins may have on leaf function. Here, we provide evidence for red-osier dogwood (Cornus stolonifera) that anthocyanins form a pigment layer in the palisade mesophyll layer that decreases light capture by chloroplasts. Measurements of leaf absorbance demonstrated

Taylor S. Feild; David W. Lee; N. Michele Holbrook

2001-01-01

437

Movement of Water from Old to Young Leaves in Three Species of Succulents  

PubMed Central

A hypothetical adaptive response of succulent plants to drought?stress is the redistribution of water from old to young leaves. We examined the effects of possible movement of water from old to young leaves in three succulent species, Carpobrotus edulis (weak CAM?inducible), Kalanchoe tubiflora (CAM) and Sedum spectabile (possibly a CAM?cycler or CAM?inducible). Old leaves were removed from plants, and photosynthesis, transpiration, f. wt?:?d. wt ratios, diurnal acid fluctuations, stomatal conductance and internal CO2 concentrations of the remaining young leaves were measured during drought?stress. Comparison was made with plants retaining old leaves. There was no evidence that water moved from old to young leaves during drought?stress as previously hypothesized. Only in drought?stressed plants of K. tubiflora, were photosynthetic and transpiration rates of young leaves greater on shoots with old leaves removed compared with attached. There was a trend in all species for greater fluctuations in acidity in young leaves on shoots that lacked older leaves. For two of the three species studied, the f. wt?:?d. wt ratios of young leaves were greater under drought?stress, on shoots with old leaves removed than with them attached. Absence of old leaves may reduce competition for water with young leaves, which consequently have higher water content and greater photosynthetic rates. PMID:12907468

RABAS, A. R.; MARTIN, C. E.

2003-01-01

438

Hackelia cinerea (Piper) Johnst. gray stickseed Boraginaceae (Borage Family) Hackelia cinerea gray stickseed Status: State Sensitive Rank: G4?S1  

E-print Network

Perennial, 8 to 32 inches tall. Stems several or sometimes solitary, strigose and generally also more or less spreading-bristly. Leaves are hirsute or hispid-hirsute with spreading or subappressed hairs, and often strigose or strigose-sericeous especially beneath, the basal ones well-developed and commonly persistent, petiolate, oblanceolate or narrowly elliptic, 2 to 8 inches long and 1/8 to 2/3 inch wide, the cauline ones mostly sessile and progressively smaller, lanceolate to linear or linearoblong. Corolla is white with a yellow eye, the limb to inch wide, the fornices evidently papillate-hairy. Marginal prickles of the nutlet are united for about 1/3 to their length to form an evident cupulate border. Intramarginal prickles are small. Identification Tips: The taxon can be readily distinguished from other Northwest members of the genus by the uniformly sericeous condition on the upper surface of the leaves, and the shape, texture, and surface of the fornices (Gentry and Carr 1976). There is overlap with Hackelia diffusa var. arida and H. ciliata in most other characters. A technical key is recommended for positive identification. Phenology: Flowers from mid-May through July. Range: Occurs in northwestern Montana, north and central Idaho to Spokane County, Washington. The species has also been found in Lincoln and Stevens counties in Washington. All known occurrences are along the Spokane River or its tributaries. All sites are within the Columbia Basin physiographic province. Habitat: This species occurs in open or sparsely forested areas, especially on cliffs or talus, or other exposed rock, often in mossy cracks. Associated species include Eupatorium occidentale, Physocarpus malvaceus, Philadelphus lewisii, Amelanchier

General Description; Adapted Hitchcock

439

Phenolic compounds analysis of root, stalk, and leaves of nettle.  

PubMed

Types of nettles (Urtica dioica) were collected from different regions to analyze phenolic compounds in this research. Nettles are specially grown in the coastal part. According to this kind of properties, nettle samples were collected from coastal part of (Mediterranean, Aegean, Black sea, and Marmara) Turkey. Phenolic profile, total phenol compounds, and antioxidant activities of nettle samples were analyzed. Nettles were separated to the part of root, stalk, and leaves. Then, these parts of nettle were analyzed to understand the difference of phenolic compounds and amount of them. Nettle (root, stalk and leaves) samples were analyzed by using High-Performance Liquid Chromatography with Diode-Array Detection (HPLC-DAD) to qualitative and quantitative determination of the phenolic compounds. Total phenolic components were measured by using Folin-Ciocalteu method. The antioxidant activity was measured by using DPPH (2,2-diphenyl-1-picrylhydrazyl) which is generally used for herbal samples and based on single electron transfer (SET). PMID:22593694

Otles, Semih; Yalcin, Buket

2012-01-01

440

Underground leaves of Philcoxia trap and digest nematodes  

PubMed Central

The recently described genus Philcoxia comprises three species restricted to well lit and low-nutrient soils in the Brazilian Cerrado. The morphological and habitat similarities of Philcoxia to those of some carnivorous plants, along with recent observations of nematodes over its subterranean leaves, prompted the suggestion that the genus is carnivorous. Here we report compelling evidence of carnivory in Philcoxia of the Plantaginaceae, a family in which no carnivorous members are otherwise known. We also document both a unique capturing strategy for carnivorous plants and a case of a plant that traps and digests nematodes with underground adhesive leaves. Our findings illustrate how much can still be discovered about the origin, distribution, and frequency of the carnivorous syndrome in angiosperms and, more generally, about the diversity of nutrient-acquisition mechanisms that have evolved in plants growing in severely nutrient-impoverished environments such as the Brazilian Cerrado, one of the world's 34 biodiversity hotspots. PMID:22232687

Pereira, Caio G.; Almenara, Daniela P.; Winter, Carlos E.; Fritsch, Peter W.; Lambers, Hans; Oliveira, Rafael S.

2012-01-01

441

Bioactive molecules in Kalanchoe pinnata leaves: extraction, purification, and identification.  

PubMed

Kalanchoe pinnata (Lam.) Pers. (syn. Bryophyllum pinnatum; family Crassulaceae) is a popular plant used in traditional medicine in many temperate regions of the world and particularly in South America. In Guyana, the leaves are traditionally used as an anti-inflammatory and antiseptic to treat coughs, ulcers, and sores. The purpose of this study was to implement a method for targeting and identifying molecules with antimicrobial activity, which could replace chemical preservatives in cosmetic applications. The leaves were extracted by a method based on pressurized liquid extraction (PLE), using different solvents. A study of antimicrobial activity and cytotoxicity tests were performed to select the most interesting extract. To isolate one or more active molecules, the selected crude extract was fractionated by centrifugal partition chromatography (CPC) and then antimicrobial activity and cytotoxicity of each fraction were tested under the same procedure. The last step consisted of identifying the main compounds in the most active fraction by LC-MS/MS. PMID:20714893

El Abdellaoui, Saïda; Destandau, Emilie; Toribio, Alix; Elfakir, Claire; Lafosse, Michel; Renimel, Isabelle; André, Patrice; Cancellieri, Perrine; Landemarre, Ludovic

2010-10-01

442

Flowering time regulation: photoperiod- and temperature-sensing in leaves  

PubMed Central

Plants monitor changes in photoperiod and temperature to synchronize their flowering with seasonal changes to maximize fitness. In the Arabidopsis photoperiodic flowering pathway, the circadian clock-regulated components, such as FLAVIN-BINDING, KELCH REPEAT, F-BOX 1 and CONSTANS, both of which have light-controlled functions, are crucial to induce the day-length specific expression of the FLOWERING LOCUS T (FT) gene in leaves. Recent advances indicate that FT transcriptional regulation is central for integrating the information derived from other important internal and external factors, such as developmental age, amount of gibberellic acid, and the ambient temperature. In this review, we describe how these factors interactively regulate the expression of FT, the main component of florigen, in leaves. PMID:23790253

Song, Young Hun; Ito, Shogo; Imaizumi, Takato

2013-01-01

443

Antioxidant and anticancer constituents from the leaves of Liriodendron tulipifera.  

PubMed

Sixteen compounds were extracted and purified from the leaves of Liriodendron tulipifera. These compounds include aporphines, oxoaporphine, coumarin, sesquiterpene lactone, benzenoids, cyclitol and steroids. (+)-Norstephalagine (2) (an aporphine) and scopoletin (8) (a coumarin) were isolated from Liriodendron tulipifera leaves from the first time. The identified compounds were screened for their antiradical scavenging, metal chelating and ferric reducing power activities. The results have showed that these compounds have antioxidative activity. The study has also examined the chemopreventive property of the isolated compounds against human melanoma cells A375. The results shown that (-)-anonaine (1), (-)-liridinine (3), (+)-lirinidine (6), lysicamine (7) and epitulipinolide diepoxide (9) significantly inhibited the proliferation of melanoma cells. These results revealed that these compounds have antioxidative activity and chemopreventive activity in skin melanoma cells. PMID:24705566

Kang, Ya-Fei; Liu, Chi-Ming; Kao, Chiu-Li; Chen, Chung-Yi

2014-01-01

444

Spectral and spectral-polarization characteristics of potato leaves  

NASA Astrophysics Data System (ADS)

The results of laboratory investigations of the spectral and spectral-polarization characteristics of radiation reflected from the leaves of potato (Solanum tuberosum) of different varieties are discussed. During the vegetation season of 1997, the angular dependence of the degree and azimuth of polarization of radiation reflected from potato leaves as well as the scattering indicatrices in the range 380 1080 nm were determined by a specially developed method with the use of a laboratory goniometric setup. The relationship between the spectral polarization characteristics of radiation and biological parameters of the potato has been obtained with the help of different methods of statistical analysis and explained on the basis of the known physical mechanisms.

Belyaev, B. I.; Belyaev, Yu. V.; Chumakov, A. V.; Nekrasov, V. P.; Shuplyak, V. I.

2000-07-01

445

Antimicrobial activity of endophytic fungi isolated from Swietenia macrophylla leaves.  

PubMed

The endophytic fungi isolated from leaves of Swietenia macrophylla of different ages were examined for antimicrobial activity. The agar plug diffusion assay was used for primary screening, followed by the disc diffusion method. A total of 461 filamentous endophytic fungi were isolated and cultured to examine their antimicrobial properties. In the primary screen, 315 isolates (68.3%) exhibited activity against at least one of the test pathogenic microorganisms. The percentage of isolates exhibiting antimicrobial activity increased with leaf age. Endophytic fungal assemblages, as well as those isolates exhibiting antimicrobial properties appeared to increase with leaf age. The main antimicrobial compounds were produced extracellularly by the endophytic fungi. The results suggest that healthy leaves at older stages of growth can be a potential source for the isolation of endophytic fungi with antimicrobial properties. PMID:24689302

Ibrahim, Darah; Lee, Chong Chai; Sheh-Hong, Lim

2014-02-01

446

Identification of phenylpropanoids in fig (Ficus carica L.) leaves.  

PubMed

In this study, the phenylpropanoid composition and antioxidant activity of identified components in fig (Ficus carica L.) leaves were examined. Known polyphenols rutin, isoschaftoside, isoquercetin, and chlorogenic acid were identified. Furthermore, caffeoylmalic acid (CMA) was the most abundant polyphenol and was identified for the first time. CMA exhibited antioxidant activity similar to that of vitamin C or catechin. Psoralen and bergapten were identified as known furanocoumarins, with psoralen being the most abundant. Moreover, psoralic acid glucoside (PAG) was identified for the first time. As a precursor of psoralen, PAG content was equivalent to the psoralen content in moles. Notably, the content of these compounds varied between the five fig varieties, and the furanocoumarin and PAG contents varied more than that of the polyphenols. Further investigations concerning the influence of CMA and PAG on human health are necessary to elucidate functionalities of fig leaves. PMID:25198243

Takahashi, Toru; Okiura, Aya; Saito, Keita; Kohno, Masahiro

2014-10-15

447

Antifungal aryltetralin lignans from leaves of Podophyllum hexandrum  

Microsoft Academic Search

Two aryltetralin lignans, 4?-O-demethyldehydropodophyllotoxin and picropodophyllone, which were earlier reported as semi-synthetic products, were isolated from the leaves of Podophyllum hexandrum of Pakistani origin. Two known aryltetralin lignans, isopicropodophyllone and dehydropodophyllotoxin, were also isolated. Structures were identified by spectroscopic methods. The two new lignans showed strong antifungal activity against Epidermophyton floccosum, Curvularia lunata, Nigrospora oryzae, Microsporum canis, Allescheria boydii and

Atta-ur-Rahman; M. Ashraf; M. Iqbal Choudhary; M. H. Kazmi

1995-01-01

448

Flavonoids in the leaves of twenty-eight polygonaceous plants  

Microsoft Academic Search

Flavonoids in the leaves of twenty-eight species belonging to the Polygonaceae were studied. Thirty-three kinds of flavonoids\\u000a were isolated, and eighteen kinds were obtained as crystals. Quercetin glycosides were commonly found in the family. In the\\u000a quercetin glycosides, 3-O-rhamnoside was most frequently found: 3-O-glucuronide is also distributed widely. Myricetin glycosides were rare. Methylated flavonols were found in some species of

Masaru Kawasaki; Takeshi Kanomata; Kunijiro Yoshitama

1986-01-01

449

What do red and yellow autumn leaves signal?  

Microsoft Academic Search

The widespread phenomenon of red and yellow autumn leaves has recently attracted considerable scientific attention. The fact\\u000a that this phenomenon is so prominent in the cooler, temperate regions and less common in warmer climates is a good indication\\u000a of a climate-specific effect. In addition to the putative multifarious physiological benefits, such as protection from photoinhibition\\u000a and photo-oxidation, several plant\\/animal interaction

Simcha Lev-Yadun; Kevin S. Gould

2007-01-01

450

Chemical constituents from the leaves of Psidium guajava  

Microsoft Academic Search

Five constituents including one new pentacyclic triterpenoid guajanoic acid (1) and four known compounds ?-sitosterol (2), uvaol (3), oleanolic acid (4), and ursolic acid (5) have been isolated from the leaves of Psidium guajava.The new constituent1has been characterized as 3?-p-E-coumaroyloxy-2?-methoxyurs-12-en-28-oic acid through 2D NMR techniques and chemical transformations. This is the first report of isolation of compound 3 from the

Sabira Begum; Syed Imran Hassan; Syed Nawazish Ali; Bina S. Siddiqui

2004-01-01

451

Friedolanostanes and lanostanes from the leaves of Garcinia hombroniana.  

PubMed

Five new triterpenes, one 17,14-friedolanostane (garcihombronane F, 1), three 17,13-friedolanostanes (garcihombronanes G-I, 2-4), and one lanostane (garcihombronane J, 5), were isolated from the leaves of Garcinia hombroniana together with nine known compounds including five triterpenes, two ionone-derived glycosides, and two flavonoid glucosides. Their structures were identified by analysis of spectroscopic data and comparison of the NMR data with those previously reported. PMID:16124765

Rukachaisirikul, Vatcharin; Saelim, Somsak; Karnsomchoke, Pueksa; Phongpaichit, Souwalak

2005-08-01

452

Flavonoids in the leaves of Asclepias incarnata L.  

PubMed

Seven flavonoid compounds: quercelin 3-O-beta-galactopyranoside, 3-O-beta-glucopyranoside, 3-O-arabinoside, 3-O-beta-glucopyranosyl (1-->2)-beta-galactopyranoside, 3-O-beta-xylopyranosyl (1-->2)-beta-galactopyranoside, 3-O-alpha-rhamnopyranosyl (1-->2)-beta-galactopyranoside and kaempferol 3-beta-glucopyranoside were isolated and identified from the leaves of Asclepias incarnata, L. (Asclepiadaceae). PMID:15080595

Sikorska, Maria

2003-01-01

453

Phenylpropanoid glycosides from the leaves of Paulownia coreana.  

PubMed

Study on the water soluble fraction from the leaves of Paulownia coreana led to the isolation of verbascoside (1), isoverbascoside (2), campneoside II (3), and a new phenylpropanoid glycoside, (R,S)-7-hydroxy-7-(3,4-dihydroxyphenyl)-ethyl-O-alpha-L-rhamnopyranosyl(1 --> 3)-beta-d-(6-O-caffeoyl)-glucopyranoside (4). The structures of these compounds were established on the basis of spectroscopic evidence. PMID:18266154

Kim, Jin-Kyu; Si, Chuan-Ling; Bae, Young-Soo

2008-02-15

454

Identification of a senescence-related protease in coriander leaves  

Microsoft Academic Search

Senescence-related protease may play an important role in leaf senescence. By improved SDS-Gelatin-PAGE assay, a 63 ku senescence-related\\u000a protease (63 SRP) in coriander leaves was identified. Activity of 63 SRP was increased in parallel to the advance of coriander\\u000a leaf senescence, and inhibited by treating the leaf with gibberellic acid, and enhanced by ethylene treatment. The 63 SRP\\u000a was suggested

Weibo Jiang; Xiangjuan Zhou; Yumei Zhao; Pengcheng Liu

2002-01-01

455

Thermal Inactivation Kinetics of Peroxidase in Coriander Leaves  

Microsoft Academic Search

Design of efficient blanching treatments requires knowledge of critical factors such as enzyme inactivation kinetic parameters\\u000a and relative proportions of heat-labile and heat-resistant fractions, which is unique in each vegetable. Thermal inactivation\\u000a curves for peroxidase in coriander leaves were determined in the temperature range of 70 to 100 °C and in steam. The isothermal\\u000a data were statistically treated using both linear

S. G. Rudra; S. Basu; B. C. Sarkar

2008-01-01

456

Ultrasonically assisted antioxidant extraction from grape stalks and olive leaves  

NASA Astrophysics Data System (ADS)

Grape stalks and olive leaves present high amount of phenolic compounds with antioxidant properties. The extraction of these compounds may be considered a way to increase in value both agro-food by-products. Ultrasound is widely applied in extraction due to its effects (cavitation, microstirring or sponge effect) over the process. The goal of this work was to address the application of ultrasound on the antioxidant extraction of olive leaves and grape stalk. For that purpose, the extraction of antioxidant compounds from grape stalks and olive leaves, previously dried at 100 °C, were carried out using a ethanolic solution (80 % v/v) at 60 °C. Extractions were carried out with (US; 30 kHz; 600W)) and agitation (AG) without ultrasound application. In the AG experiments, the solution was agitated with a stirrer. Samples were obtained at different extraction time (10, 30, 60, 120, 180, 240, 360, 480 and 1440 min) and their antioxidant capacity was measured using FRAP method. The Naik model was used to model the extraction kinetics, being identified the antioxidant capacity of extracts at the equilibrium (Y eq) and the initial velocity of extraction (Y eq/B). For grape stalks, the antioxidant capacity of extracts at the equilibrium (Y eq) and the initial velocity of extraction (Y eq/B) were higher in AG experiments than in US experiments. In the olive leaves extractions, the Y eq/B was of the same order for both treatments but Y eq was significantly higher for US experiments. The different influence of ultrasound for both by-products can be explained from their different geometry and structure.

Cárcel, Juan A.; García-Pérez, José V.; Mulet, Antonio; Rodríguez, Ligia; Riera, Enrique

2010-01-01

457

Factors affecting the determination of net photosynthesis of apple leaves  

Microsoft Academic Search

Net photosynthesis (Pn) was determined on individual leaves of greenhouse grown Golden Delicious on seedling rootstocks. Saturation light intensity varied among experiments, but was typically between 2000 and 4000 ft-c. Pn increased with increasing air flow rates up to about 2.5 liters min⁻¹ with only slight increases above this rate. Good comparisons of Pn could be made on either a

Barden

1971-01-01

458

Chlorophyllase activity in developing leaves of Phaseolus vulgaris L  

Microsoft Academic Search

In crude extracts of primary leaves from dark grown seedlings of Phaseolus vulgaris L., relatively high hydrolytic activity of chlorophyllase (chlorophyll-chlorophyllido-hydrolase, EC 3.1.1.14) was observed. When plants were exposed to continuous illumination, the enzyme activity in the extracts was doubled within 3 days and both chlorophyll a and b were synthesized. However, when exposed to periodic illumination (1 min light-59

W. A. W. Moll; B. Wit; R. Lutter

1978-01-01

459

Photosystem II efficiency in low chlorophyll, iron-deficient leaves  

Microsoft Academic Search

Iron deficiency (iron chlorosis) is the major nutritional stress affecting fruit tree crops in calcareous soils in the Mediterranean\\u000a area. This work reviews the changes in PS II efficiency in iron-deficient leaves. The iron deficiency-induced leaf yellowing\\u000a is due to decreases in the leaf concentrations of photosynthetic pigments, chlorophylls and carotenoids. However, carotenoids,\\u000a and more specifically lutein and the xanthophylls

Javier Abadía; Fermín Morales; Anunciación Abadía

1999-01-01

460

Systemic signalling of environmental cues in Arabidopsis leaves  

Microsoft Academic Search

Light intensity and atmospheric CO2 partial pressure are two environmental signals known to regulate stomatal numbers. It has previously been shown that if a mature Arabidopsis leaf is supplied with either elevated CO2 (750 ppm instead of ambient at 370 ppm) or reduced light levels (50 lmol m22 s21 instead of 250 lmol m22 s21), the young, developing leaves that

S. A. Coupe; B. G. Palmer; J. A. Lake; S. A. Overy; K. Oxborough; F. I. Woodward; J. E. Gray; W. P. Quick

2010-01-01

461

Cassava leaves as protein source for pigs in Central Vietnam  

Microsoft Academic Search

The aim of the studies described in this thesis was to evaluate the use of cassava leaves as protein sources for pigs when used at high levels in the diet, either in fresh form or with simplified methods of processing.\\u000a\\u000aIn twenty cassava varieties taken from the upper part of the plant at the root harvesting, the crude protein varied

Du Thanh Hang

2007-01-01

462

Photosynthetic symmetry of sun and shade leaves of different orientations  

Microsoft Academic Search

The photosynthetic responses to light of leaves irradiated on the adaxial or abaxial surfaces, were measured for plants with contrasting leaf orientations. For vertical-leaf species of open habitats (Eryngium yuccifolium and Silphium terebinthinaceum), photosynthetic rates were identical when irradiated on either surface. However, for horizontal-leaf species of open habitats (Ambrosia trifida and Solidago canadensis), light-saturated rates of photosynthesis for adaxial

Evan H. Lucia; Hemanth D. Shenoi; Shawna L. Naidu; Thomas A. Day

1991-01-01

463

Polarized directional reflectance from laurel and mullein leaves  

NASA Astrophysics Data System (ADS)

The ability to perform polarimetric imaging throughout the visible and infrared (IR) wavebands has improved considerably in the past decade. Systems now exist that enable measurements to be made of all four Stokes parameters arising from each pixel in the image. The question of whether polarimetric imaging offers an advantage over conventional imaging methods for discrimination of plant type in scenes of natural vegetation remains to be answered. Although the size of a leaf may be below the spatial resolution of an imaging system, the polarimetric properties of individual leaves may affect the data observed from a tree or forest canopy. We report the results of measurements of the polarized hemispherical directional reflectance (HDR), which is related to the directional emissivity, and bidirectional reflectance distribution function (BRDF) from two examples of leaves. To completely characterize the polarimetric properties of a leaf, and ultimately a leaf canopy, an extensive measurement of the polarized BRDF and HDR of individual leaves is required. This is necessary because of the large range of possible relative orientations of the illumination, leaf and observer, and the range of polarization states of incident radiation. We report a limited set of laboratory measurements designed to investigate whether any gross polarimetric difference exist between two dissimilar types of plant leaves in the visible, near IR (NIR), and IR spectral wavebands. Laurel (prunus laurecatious) has a wax surface creating a gloss or glabrous appearance to the leaf. The surface of mullein (verbascum thapsus) is highly pubescent with a dense layer of hair over the adaxial surface, creating a highly diffuse surface reflectance. Significant differences are found between the two species of leaf in the measured polarized directional reflectance and emissivity.

Raven, Peter N.; Jordan, David L.; Smith, Catherine E.

2002-05-01

464

Sesquiterpenes from the leaves of Ligularia fischeri var. spiciformis.  

PubMed

From the leaves of Ligularia fischeri var. spiciformis, a new eremophilanolide, 8 alpha-methoxy-6-oxoeremophil-7(11)-en-12,8-olide (6-oxoeremophilenolide) and a eudesmane-type sesquiterpene, (+)-intermedeol were isolated. The structures were determined on the basis of 2D-NMR spectral data. Data on cytotoxicity showed that the latter was clearly more potent than the former compound. PMID:11199147

Park, H J; Kwon, S H; Yoo, K O; Sohn, I C; Lee, K T; Lee, H K

2000-12-01

465

Effects of gravity on transpiration of plant leaves.  

PubMed

To clarify effects of gravity on the water vapor exchange between plants and the ambient air, we evaluated the transpiration rate of plant leaves at 0.01, 1.0, and 2.0 g for 20 s each during parabolic airplane flights. The transpiration rates of a strawberry leaf and a replica leaf made of wet cloth were determined using a chamber method with humidity sensors. Absolute humidity at 3 and 8 mm below the lower surface of leaves was measured to evaluate the effect of gravity on humidity near leaves and estimate their transpiration rate. The transpiration rate of the replica leaf decreased by 42% with decreasing gravity levels from 1.0 to 0.01 g and increased by 31% with increasing gravity levels from 1.0 to 2.0 g. Absolute humidity near the intact strawberry leaf was 5 g m(-3) at ambient absolute humidity of 2.3 g m(-3) and gravity of 1.0 g. The absolute humidity increased by 2.5 g m(-3) with decreasing gravity levels from 1.0 to 0.01 g. The transpiration rate of the intact leaf decreased by 46% with decreasing gravity levels from 1.0 to 0.01 g and increased by 32% with increasing gravity levels from 1.0 to 2.0 g. We confirmed that the transpiration rate of leaves was suppressed by retarding the water vapor transfer due to restricted free air convection under microgravity conditions. PMID:19426314

Hirai, Hiroaki; Kitaya, Yoshiaki

2009-04-01

466

Characterization of a cadmium-binding complex of cabbage leaves  

Microsoft Academic Search

The chemical nature of a principle, inducible cadmium-binding complex which accumulates in cabbage leaves was studied and compared with that of animal metallothionein and copper-binding proteins isolated from various organisms. The apparent molecular weight of native cabbage complex and carboxymethylated ligand of the complex under native conditions as determined by gel filtration was about 10,000 daltons. Under denaturing conditions their

G. J. Wagner

1984-01-01

467

5- O-glucosyldihydroflavones from the leaves of Helicia cochinchinensis  

Microsoft Academic Search

From the leaves of Helicia cochinchinensis, collected on Okinawa Island, seven phenolic glucosides and two terpenic glucosides were isolated. Five of the phenolic glucosides were previously known, being identified with p-coumaric and ferulic acids glucosyl esters, rhodioloside, helicidiol, and naringenin 5-O-?-d-glucopyranoside. The structures of two other phenolic glucosides, named heliciosides A and B, were elucidated to be 5-O-?-d-glucosides of 3-hydroxyflavanone,

Ken-Ichi Morimura; Asuka Gatayama; Reiki Tsukimata; Katsuyoshi Matsunami; Hideaki Otsuka; Eiji Hirata; Takakazu Shinzato; Mitsunori Aramoto; Yoshio Takeda

2006-01-01

468

Enumerative sequences of leaves and nodes in rational trees  

E-print Network

Enumerative sequences of leaves and nodes in rational trees Fr'ed'erique Bassino Institut Gaspard://www­igm.univ­mlv.fr/~fbassino,beal,perring Abstract We prove that any IN­rational sequence s = (s n ) nâ??1 of nonnega­ tive integers satisfying of a rational k­ary tree. We give an efficient algorithm to get a k­ary rational tree. Particular cases

Bassino, Frédérique

469

Bioactive limonoids from the leaves of Azaridachta indica (Neem).  

PubMed

Eight new limonoids (1-8) and one new phenol glycoside (9), along with six known compounds, were isolated from the leaves of Azaridachta indica. The structures of 1-9 were elucidated on the basis of spectroscopic data analysis. Compounds isolated were assayed for their cytotoxicity against different cancer cell lines. Moreover, their ability to interact with the molecular chaperone Hsp90, affecting its biological activity, was tested. PMID:24499352

Gualtieri, Maria J; Malafronte, Nicola; Vassallo, Antonio; Braca, Alessandra; Cotugno, Roberta; Vasaturo, Michele; De Tommasi, Nunziatina; Dal Piaz, Fabrizio

2014-03-28

470

Antioxidant properties and stability of aegle marmelos leaves extracts  

Microsoft Academic Search

Aegle marmelos (AM) leaves were extracted with methanol (ME), ethanol (EE), water (WE) and analyzed for antioxidant activities by DPPH radical\\u000a scavenging method, reducing power and in vitro inhibition by Fenton’s reagent—induced oxidation of lipid system. Stability of extracts to pH (4, 7 and 9) and temperature\\u000a (100 °C, 15 min.) was studied. The three extracts showed varying degree of efficacy in

Vanitha P. Reddy; Asna Urooj

471

Polarization of Light by Leaves and Plant Canopies  

NASA Technical Reports Server (NTRS)

This talk will focus first on the information contained in the surface-scattered light from leaves, plant canopies and surface waters. This light is in general polarized and depends upon surface roughness. Thus, for example, - The surface reflection from shiny green leaves measured in the specular direction shows no chlorophyll absorption bands, no 'red edge.' - Conversely, the degree of linear polarization of such light displays marked variation with wavelength having local maxima in the chlorophyll absorption bands and an inverted red edge. - Plant canopies with shiny leaves distributed in angle like the area on a sphere, specularly reflect sunlight in the subsolar or specular direction- but also in every other view direction. - Canopies of green plants may appear white not green when viewed obliquely toward the sun. - In a light to moderate wind, the often blindingly bright glitter of sunlight off smooth water surfaces provides a strong, angularly narrow signature reflection characteristic of inundated vegetated areas that are big sources of atmospheric methane, a climatically important greenhouse gas. (Conversely, a blindingly bright glitter-type reflection is uncharacteristic of upland or wind ruffled open water areas that are poor sources of atmospheric methane.) Because some of these results may be 'head scratchers,' it's always important to properly calibrate ones instruments. Indeed, as the second portion of the talk will show, the characteristics of the light measuring instrument, particularly its entrance aperture, may affect the results and should be taken into account during across-instrument data comparisons.

Vanderbilt, V. C.

2006-01-01

472

Revising Himself : Walt Whitman and Leaves of Grass  

NSDL National Science Digital Library

An impressive feat of literary collation, the Library of Congress presents this exhibition on Walt Whitman, probably America's first superstar author, and Whitman's book of poetry, _Leaves of Grass_. Initially published in 1855, _Leaves of Grass_ contained 12 poems. Whitman continuously revised it until his death in 1892, when it contained 400 poems. The poet added new poems, renamed older ones, reworded lines, changed punctuation, and regrouped poems (through the 1881 edition), as well as inventing typography, and posing for frontispiece portraits wearing various styles of clothing and props. (front and back views of a cardboard butterfly that Whitman posed with in 1877 are included in the show). The exhibition traces this evolution of _Leaves of Grass_ and Whitman's life, as a poet and a person, from the first appearance of the lines "I am the poet of the body, And I am the poet of the soul" in a notebook dating 1847-1950s, to the final "Deathbed edition" of 1891-1892. A wealth of interesting biographical material on Whitman, his friends and associates, his work as a teacher, tending the wounded during the Civil War, and for the federal government, also appears in the exhibit.

473

An Assessment of Wound Healing Potential of Argyreia speciosa Leaves  

PubMed Central

In North India, poultice of young unfolded leaves of Argyreia speciosa Linn. (Convolvulaceae) is used for healing wounds. In order to find scientific evidence for the traditional utilization of leaves of A. speciosa in wound healing, this investigation was carried out. A linear incision wound of about 3?cm in length and 2?mm in depth and circular excision wound of 177?mm2 full thickness were made on the dorsal region of separate groups (n = 5) of anesthetized Swiss albino mice. A simple ointment, developed by including ethanol, ethanol-water, and water extracts (10% each, separately) of A. speciosa, was applied topically to mice once daily for 14 days after wounding. To evaluate the effect of each extract, wound contraction, epithelization period, wound breaking strength, and hydroxyproline content were determined. The water extract of A. speciosa showed accelerated wound healing activity as evidenced by fast wound contraction (96.30 ± 0.52%; P < 0.01), rapid epithelization period (11.40 ± 0.60 days; P < 0.001), greater wound breaking strength (376.56 ± 21.16?g; P < 0.001), and higher hydroxyproline content (16.49 ± 1.12?mg/g; P < 0.05) of granulation tissue. The present report supports the traditional use of Argyreia speciosa leaves for wound healing and signify its relevant therapeutic potential. PMID:24688387

Yadav, Narayan Prasad; Rawat, Bindu; Rai, Vineet Kumar; Shanker, Karuna; Venkateswara Rao, Chandana

2014-01-01

474

Evaluation of acute toxicity potential of water hyacinth leaves.  

PubMed

Although higher protein yield per hectare of water hyacinth than that of soy, high protein content of its leaves and good essential amino acid pattern have been proven, its dietary toxicity for human or animal consumption has not yet been evaluated. Therefore, the acute toxicity of water hyacinth leaves has been evaluated by an animal feeding test. The concentrations of common toxic metals including cadmium, lead, platinum, palladium, tin, mercury, barium, silver, stibium and aluminum in the water hyacinth leaf powder (WHLP) used for the animal feeding test were within their maximum limits in food additives as reported by the World Health Organization. The median lethal dose (LD50) of WHLP was more than 16 g kg(-1) body weight. In the study, after feeding for 7 and 28 days, the body weight of all the mice increased. The results of hematological analysis, clinical biochemical analysis, histopathological evaluation, general dissection or investigations of internal organs, appearance and behavior observations did not indicate any adverse effects from the diet containing WHLP. It is therefore concluded that water hyacinth leaves are not acutely toxic. PMID:22933551

Wu, Wenbiao; Guo, Xiaoguang; Huang, Mingliang

2014-06-01

475

Leaving from and returning to nursing practice: contributing factors.  

PubMed

Many nurses leave nursing and never return. Others return after a period of time. Given the global shortage of nurses a better understanding of these movements is needed. The present study focused on nurses who had been out of nursing for more than five years, and explored factors that influenced their leaving and return to practice. All the nurses who had undertaken a Competency Assessment Programme at a given New Zealand tertiary institution during 2005 were invited to participate. Of the 70 questionnaires mailed out 32 (44.5%) were completed and returned. Quantitative data were analysed using Microsoft Excel, and the qualitative data were coded and analysed by means of content analysis. For each, leaving and returning, three key issues emerged. Nurses left for personal reasons, to seek a career change, or because of poor working conditions. They returned when they had the personal freedom to do so, for fiscal reasons, or because they were motivated by some sense of unfinished business. These findings indicate that it is important for educators involved with Competency Assessment Programmes to collaborate with employers in ensuring that there are opportunities for re-entry to positive work environments, with a degree of flexibility that suits the demographic characteristics of those nurses returning to practice. PMID:19928648

Jamieson, Isabel; Taua, Chris

2009-07-01

476

Arsenic stress activates MAP kinase in rice roots and leaves.  

PubMed

The toxic metalloid arsenite has become a potential threat to rice growing regions leading to serious contamination in food chain. In the present study effect of different physiological concentration of arsenite that is toxic and triggers the molecular events were evaluated in rice seedlings. Along with severe effect on the growth of rice seedling, production of reactive oxygen species (ROS) and nitric oxide (NO) in arsenite treated rice roots was also observed. Activation of a 42kDa mitogen activated protein kinase (MAPK/MPK) by arsenite was observed in rice leaves and 42 and 44kDa in roots in dose dependent manner. The activated MAPK could be immunoprecipitated with anti-phospho-tyrosine antibody, 4G10. The kinetic of MAPK activation by arsenite was found to be dose dependent. Transcript analysis of MAPK family and immunokinase assay in arsenite treated rice seedling revealed significant level of induction in OsMPK3 transcripts in leaves and OsMPK3, OsMPK4 transcripts in roots. Among MAPK kinase (MKKs) gene family, OsMKK4 transcripts were found to be induced in arsenite treated rice leaves and roots. In-silico homology modeling and docking analysis supported OsMPK3-OsMKK4 interaction. The data indicates that arsenite stress is transduced through MAPK signaling cascade in rice. PMID:21081102

Rao, Kudupudi Prabhakara; Vani, Gubbala; Kumar, Kundan; Wankhede, Dhammaprakash Pandhari; Misra, Mohit; Gupta, Meetu; Sinha, Alok Krishna

2011-02-01

477

Characterization and subcellular localization of aminopeptidases in senescing barley leaves  

NASA Technical Reports Server (NTRS)

Four aminopeptidases (APs) were separated using native polyacrylamide gel electrophoresis of cell-free extracts and the stromal fractions of isolated chloroplasts prepared from primary barley (Hordeum vulgare L., var Numar) leaves. Activities were identified using a series of aminoacyl-beta-naphthylamide derivatives as substrates. AP1, 2, and 3 were found in the stromal fraction of isolated chloroplasts with respective molecular masses of 66.7, 56.5, and 54.6 kilodaltons. AP4 was found only in the cytoplasmic fraction. No AP activity was found in vacuoles of these leaves. It was found that 50% of the L-Leu-beta-naphthylamide and 25% of the L-Arg-beta-naphthylamide activities were localized in the chloroplasts. Several AP activities were associated with the membranes of the thylakoid fraction of isolated chloroplasts. AP1, 2, and 4 reacted against a broad range of substrates, whereas AP3 hydrolyzed only L-Arg-beta-naphthylamide. Only AP2 hydrolyzed L-Val-beta-naphthylamide. Since AP2 and AP3 were the only ones reacting against Val-beta-naphthylamide and Arg-beta-naphthylamide, respectively, several protease inhibitors were tested against these substrates using a stromal fraction from isolated chloroplasts as the source of the two APs. Both APs were sensitive to both metallo and sulfhydryl type inhibitors. Although AP activity decreased as leaves senesced, no new APs appeared on gels during senescence and none disappeared.

Thayer, S. S.; Choe, H. T.; Rausser, S.; Huffaker, R. C.

1988-01-01

478

Antioxidant and antityrosinase proanthocyanidins from Polyalthia longifolia leaves.  

PubMed

In the present study the structure of proanthocyanidins from Polyalthia longifolia leaves was characterized with (13)C nuclear magnetic resonance, high performance liquid chromatography electrospray ionization mass spectrometry, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analyses. The results showed that the proanthocyanidins were mixture of homopolymers of B-type procyanidins with degree of polymerization up to 14-mer. Furthermore, the antioxidant activity of the proanthocyanidins was studied through 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) free-radical scavenging activities, and ferric reducing/antioxidant power assays. In addition, antityrosinase activity of the proanthocyanidins was investigated. The IC50 for 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) free-radical scavenging activity of the proanthocyanidins were 89.32 ± 12.07 and 76.79 ± 5.88 ?g/mL, respectively; the ferric reducing/antioxidant power value was 710.54 ± 142.82 mg ascorbic acid equivalent/g dry weight. The IC50 for antityrosinase activity was 773.09 ± 1.47 ?g/mL. In conclusion, the proanthocyanidins from P. longifolia leaves exhibited potent antioxidant and antityrosinase activities. This research would provide scientific evidence for the use of proanthocyanidins from P. longifolia leaves as antioxidant and antityrosinase agents. PMID:24863181

Chen, Xiao-Xin; Liang, Ge; Chai, Wei-Ming; Feng, Hui-Ling; Zhou, Han-Tao; Shi, Yan; Chen, Qing-Xi

2014-11-01

479

Distribution of cadmium in leaves of Thlaspi caerulescens.  

PubMed

Knowledge of the intracellular distribution of Cd in leaves is necessary in order to understand the mechanisms of hyperaccumulation in Thlaspi caerulescens. Ganges and Prayon, two ecotypes accumulating Cd to different levels, were grown in nutrient medium containing varying concentrations (0, 5, 10, 50, and 100 microM) of Cd. Several different approaches were combined in this study to (i) validate the results obtained by a specific method and (ii) establish the link between observations and measurements performed at different scales. In both ecotypes, Cd, localized by autoradiography, was found mainly at the edges of the leaves, but also in points of higher concentration spread over the whole limb surface. This localization was clearly correlated with the necrotic spots observed on Prayon leaves. Scanning electron microscopy coupled with energy dispersive X-ray microanalysis (cryo-SEM-EDXMA) and tissue fractionation (apoplasm, cell walls, mesophyll protoplasts, and lower epidermis) showed that Cd had similar patterns of distribution in leaf cells of both ecotypes. Cadmium was found both inside the cells and in the cell walls, mainly in the large epidermal cells but also in small epidermal cells. All the methods used agreed well and the results indicated that metal storage in the plants studied involves more than one compartment and that Cd is stored principally in the less metabolically active parts of leaf cells. PMID:15642714

Cosio, Claudia; DeSantis, Laura; Frey, Beat; Diallo, Saliou; Keller, Catherine

2005-02-01

480

Osmotic Stress-Induced Polyamine Accumulation in Cereal Leaves 1  

PubMed Central

Arginine decarboxylase activity increases 2- to 3-fold in osmotically stressed oat leaves in both light and dark, but putrescine accumulation in the dark is only one-third to one-half of that in light-stressed leaves. If arginine or ornithine are supplied to dark-stressed leaves, putrescine rises to levels comparable to those obtained by incubation under light. Thus, precursor amino acid availability is limiting to the stress response. Amino acid levels change rapidly upon osmotic treatment; notably, glutamic acid decreases with a corresponding rise in glutamine. Difluoromethylarginine (0.01-0.1 millimolar), the enzyme-activated irreversible inhibitor of arginine decarboxylase, prevents the stress-induced putrescine rise, as well as the incorporation of label from [14C]arginine, with the expected accumulation of free arginine, but has no effect on the rest of the amino acid pool. The use of specific inhibitors such as ?-difluoromethylarginine is suggested as probes for the physiological significance of stress responses by plant cells. PMID:16663552

Flores, Hector E.; Galston, Arthur W.

1984-01-01

481

Regulation of Monoterpene Accumulation in Leaves of Peppermint1  

PubMed Central

Plants synthesize numerous classes of natural products that accumulate during development and are thought to function as constitutive defenses against herbivores and pathogens. However, little information is available about how the levels of such defenses are regulated. We measured the accumulation of monoterpenes, a model group of constitutive defenses, in peppermint (Mentha × piperita L.) leaves and investigated several physiological processes that could regulate their accumulation: the rate of biosynthesis, the rate of metabolic loss, and the rate of volatilization. Monoterpene accumulation was found to be restricted to leaves of 12 to 20 d of age, the period of maximal leaf expansion. The rate of monoterpene biosynthesis determined by 14CO2 incorporation was closely correlated with monoterpene accumulation, as determined by gas chromatographic analysis, and appeared to be the principal factor controlling the monoterpene level of peppermint leaves. No significant catabolic losses of monoterpenes were detected throughout leaf development, and monoterpene volatilization was found to occur at a very low rate, which, on a monthly basis, represented less than 1% of the total pool of stored monoterpenes. The composition of volatilized monoterpenes differed significantly from that of the total plant monoterpene pool, suggesting that these volatilized products may arise from a separate secretory system. With the demonstration that the rate of biosynthesis is the chief process that determines monoterpene accumulation in peppermint, efforts to improve production in this species can now focus on the genes, enzymes, and cell differentiation processes that regulate monoterpene biosynthesis. PMID:10631264

Gershenzon, Jonathan; McConkey, Marie E.; Croteau, Rodney B.

2000-01-01

482

29 CFR 825.119 - Leave for treatment of substance abuse.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Leave for treatment of substance abuse. 825.119 Section 825.119 Labor...Act § 825.119 Leave for treatment of substance abuse. (a) Substance abuse may be a serious health condition if...

2013-07-01

483

29 CFR 825.119 - Leave for treatment of substance abuse.  

...2014-07-01 false Leave for treatment of substance abuse. 825.119 Section 825.119 Labor...Act § 825.119 Leave for treatment of substance abuse. (a) Substance abuse may be a serious health condition if...

2014-07-01

484

29 CFR 825.119 - Leave for treatment of substance abuse.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Leave for treatment of substance abuse. 825.119 Section 825.119 Labor...Act § 825.119 Leave for treatment of substance abuse. (a) Substance abuse may be a serious health condition if...

2012-07-01

485

29 CFR 825.119 - Leave for treatment of substance abuse.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Leave for treatment of substance abuse. 825.119 Section 825.119 Labor...Act § 825.119 Leave for treatment of substance abuse. (a) Substance abuse may be a serious health condition if...

2010-07-01

486

29 CFR 825.119 - Leave for treatment of substance abuse.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Leave for treatment of substance abuse. 825.119 Section 825.119 Labor...Act § 825.119 Leave for treatment of substance abuse. (a) Substance abuse may be a serious health condition if...

2011-07-01

487

25 CFR 39.119 - When must a student leave a gifted and talented program?  

... false When must a student leave a gifted and talented program? 39.119 Section... Indian School Equalization Formula Gifted and Talented Programs § 39.119 When must a student leave a gifted and talented program? A student...

2014-04-01

488

25 CFR 39.119 - When must a student leave a gifted and talented program?  

Code of Federal Regulations, 2012 CFR

... true When must a student leave a gifted and talented program? 39.119 Section... Indian School Equalization Formula Gifted and Talented Programs § 39.119 When must a student leave a gifted and talented program? A student...

2012-04-01

489

25 CFR 39.119 - When must a student leave a gifted and talented program?  

Code of Federal Regulations, 2011 CFR

... false When must a student leave a gifted and talented program? 39.119 Section... Indian School Equalization Formula Gifted and Talented Programs § 39.119 When must a student leave a gifted and talented program? A student...

2011-04-01

490

25 CFR 39.119 - When must a student leave a gifted and talented program?  

Code of Federal Regulations, 2013 CFR

... false When must a student leave a gifted and talented program? 39.119 Section... Indian School Equalization Formula Gifted and Talented Programs § 39.119 When must a student leave a gifted and talented program? A student...

2013-04-01

491

25 CFR 39.119 - When must a student leave a gifted and talented program?  

Code of Federal Regulations, 2010 CFR

... false When must a student leave a gifted and talented program? 39.119 Section... Indian School Equalization Formula Gifted and Talented Programs § 39.119 When must a student leave a gifted and talented program? A student...

2010-04-01

492

75 FR 8424 - Culturally Significant Objects Imported for Exhibition Determinations: “Leaves From an Austrian...  

Federal Register 2010, 2011, 2012, 2013

...Significant Objects Imported for Exhibition Determinations: ``Leaves From an Austrian Mahzor'' SUMMARY: Notice is hereby given...determine that the objects to be included in the exhibition ``Leaves from an Austrian Mahzor,'' imported from abroad for...

2010-02-24

493

29 CFR 825.220 - Protection for employees who request leave or otherwise assert FMLA rights.  

Code of Federal Regulations, 2013 CFR

...example, not only refusing to authorize FMLA leave, but discouraging an employee from using such leave. It would also include manipulation by a covered employer to avoid responsibilities under FMLA, for example: (1) Transferring employees from one...

2013-07-01

494

Radioactivity of Tobacco Leaves and Radiation Dose Induced from Smoking  

PubMed Central

The radioactivity in tobacco leaves collected from 15 different regions of Greece and before cigarette production was studied in order to find out any association between the root uptake of radionuclides from soil ground by the tobacco plants and the effective dose induced to smokers from cigarette tobacco due to the naturally occurring primordial radionuclides, such as 226Ra and 210Pb of the uranium series and 228Ra of the thorium series and/or man-made radionuclides, such as 137Cs of Chernobyl origin. Gamma-ray spectrometry was applied using Ge planar and coaxial type detectors of high resolution and high efficiency. It was concluded that the activities of the radioisotopes of radium, 226Ra and 228Ra in the tobacco leaves reflected their origin from the soil by root uptake rather than fertilizers used in the cultivation of tobacco plants. Lead-210 originated from the air and was deposited onto the tobacco leaves and trapped by the trichomes. Potassium-40 in the tobacco leaves was due to root uptake either from soil or from fertilizer. The cesium radioisotopes 137Cs and 134Cs in tobacco leaves were due to root uptake and not due to deposition onto the leaf foliage as they still remained in soil four years after the Chernobyl reactor accident, but were absent from the atmosphere because of the rain washout (precipitation) and gravitational settling. The annual effective dose due to inhalation for adults (smokers) for 226Ra varied from 42.5 to 178.6 ?Sv/y (average 79.7 ?Sv/y), while for 228Ra from 19.3 to 116.0 ?Sv/y (average 67.1 ?Sv/y) and for 210Pb from 47.0 to 134.9 ?Sv/y (average 104.7 ?Sv/y), that is the same order of magnitude for each radionuclide. The sum of the effective doses of the three radionuclides varied from 151.9 to 401.3 ?Sv/y (average 251.5 ?Sv/y). The annual effective dose from 137Cs of Chernobyl origin was three orders of magnitude lower as it varied from 70.4 to 410.4 nSv/y (average 199.3 nSv/y). PMID:19440399

Papastefanou, Constantin

2009-01-01

495

Longevity of guard cell chloroplasts in falling leaves: implication for stomatal function and cellular aging  

SciTech Connect

Guard cell chloroplasts in senescing leaves from 12 species of perennial trees and three species of annual plants survived considerably longer than their mesophyll counterparts. In Ginkgo biloba, stomata from yellow leaves opened during the day and closed at night; guard cell chloroplasts from these leaves showed fluorescence transients associated with electron transport and photophosphorylation. These findings indicate that guard cell chloroplasts are highly conserved throughout the life-span of the leaf and that leaves retain stomatal control during senescence.

Zeiger, E.; Schwartz, A.

1982-11-12

496

Quantitation of chafurosides A and B in tea leaves and isolation of prechafurosides A and B from oolong tea leaves.  

PubMed

A procedure was developed for the quantitative determination of chafuroside A, a flavone C-glycoside with potent anti-inflammatory activity, and its regioisomer chafuroside B, as well as isovitexin and vitexin, by selected reaction monitoring liquid chromatography-tandem mass spectrometry (SRM LC-MS/MS) analysis. This method was successfully applied to commercial leaves of green tea, houji tea, oolong tea, and black tea. High levels of chafurosides A and B were found in oolong tea leaves that had been heated at >140 degrees C. Next, their precursors, prechafurosides A and B, were isolated from methanol extract of oolong tea leaves prepared from Shizu 7132, Camellia sinensis (L.) O. Kuntze, by partition with n-butanol and H2O and chromatography on Diaion SP-825, Sephadex LH-20, and ODS C-18, guided by assay of chafuroside formation. Prechafurosides A and B gave chafurosides A and B, respectively, in good yields when heated at 160 degrees C for 0.5 h. Solvolysis of prechafurosides A and B with pyridine and dioxane quantitatively afforded isovitexin and vitexin, respectively. On the basis of these results and physicochemical data (MS, UV, and NMR), prechafurosides A and B were concluded to be new flavone C-glycoside sulfates, isovitexin-2''-sulfate and vitexin-2''-sulfate, respectively. PMID:19572651

Ishida, Hitoshi; Wakimoto, Toshiyuki; Kitao, Yukiko; Tanaka, Shimako; Miyase, Toshio; Nukaya, Haruo

2009-08-12

497

Termination of Nutrient Import and Development of Vein Loading Capacity in Albino Tobacco Leaves  

PubMed Central

The sink-source conversion in developing leaves of tobacco (Nicotiana tabacum L.) was studied to determine whether import termination is caused by the onset of export or is related to achievement of positive carbon balance. Albino shoots were grown in vitro and grafted to detopped stems of green tobacco plants. Termination of import was studied by providing mature leaves of the stock plant with 14CO2 and detecting the presence of labeled nutrient in developing albino leaves by whole-leaf autoradiography. In albino leaves, import terminated progressively in the basipetal direction at the same stage of development as in leaves