Camphor Research Articles

The etiology and comprehensive treatment of dental pulp disease

Objective To explore the etiology and treatment of dental pulp disease.Methods The clinical data on 100 patients with dental pulp disease who had received treatment from October 2007 to November 2010 were retrospectively analyzd.The patients were randomly divided into study group and control group,50 for each group.The control group received formocresol ( FC ) or camphor phenol ( CP ) for temporary close,and then mummification agent or root canal filling agent for permanent filling.The study group was treated with tinidazole,iodoform,and dexamethasone mixture,then twist cotton or cotton balls for CP temporary close.After symptoms disappeared, mixture of tinidazole, iodoform and dexamethasone was applied to fill the root canal,reaching the tip of the canal; zinc phosphate cement powder was used for filling the bottom,and then permanent filling was completed.The success rates of temporary close and permanent filling in both groups were analyzed.Results In the study group,temporary close succeeded in 43 patients but failed in 7,with a success rate of 86.0％; permanent filling succeeded in 43 patients but failed in 7,with a success rate of 86.0％.In the control group,temporary close succeeded in 29 patients and failed in 21,with a success rate of 58.0％ permanent filling succeeded in 26 patients and failed in 24,with a success rate of 52.0％.There were significant differences between the two groups in the success rates of temporary close and permanent filling ( P ＜ 0.01 ).Conclusions The diagnosis of most dental pulp disease can be confirmed based on medical history,clinical symptoms,and examination and analysis.Timely comprehensive treatment can achieve satisfactory outcomes. Key words: Dental pulp disease; Comprehensive treatment; Etiology; Exploration

Amorphous Carbon Deposited by a Novel Aerosol-Assisted Chemical Vapor Deposition for Photovoltaic Solar Cells

Amorphous carbon (a-C) solar cells were successfully prepared using a novel and self-designed aerosol-assisted chemical vapor deposition (AACVD) method using camphor oil as a precursor. The fabricated solar cell with the configuration of Au/p-C/n-Si/Au achieved an efficiency of 0.008% with a fill factor of 0.15 for the device deposited at 0.5 h. The current–voltage (I–V) graph emphasized on the linear graph (ohmic) for the a-C thin films, whereas for the p–n device structure, a rectifying curve was obtained. The rectifying curves signify the heterojunction between the p-type a-C film and the n-Si substrate and designate the generation of electron–hole pair of the samples under illumination. Photoresponse characteristics of the deposited a-C was highlighted when being illuminated (AM 1.5 illumination: 100 mW/cm2, 25 °C). Transmittance spectrum exhibit a large transmittance value (>85%) and absorption coefficient value of 103–104 cm-1 at the visible range of 390 to 790 nm. The atomization of a liquid precursor solution into fine sub-micrometre-sized aerosol droplets in AACVD induced the smooth surface of a-C films. To the best of our knowledge, fabrication of a-C solar cell using this AACVD method has not yet been reported.

An Investigation on the Formation of Carbon Nanotubes by Two‐Stage Chemical Vapor Deposition

High density of carbon nanotubes (CNTs) has been synthesized from agricultural hydrocarbon: camphor oil using a one‐hour synthesis time and a titanium dioxide sol gel catalyst. The pyrolysis temperature is studied in the range of 700–900°C at increments of 50°C. The synthesis process is done using a custom‐made two‐stage catalytic chemical vapor deposition apparatus. The CNT characteristics are investigated by field emission scanning electron microscopy and micro‐Raman spectroscopy. The experimental results showed that structural properties of CNT are highly dependent on pyrolysis temperature changes.

Dependency of thermal conductivity on the temperature and composition of d-camphor in the neopentylglycol–d-camphor alloys

Dependencies of thermal conductivity of solid phases for neopentylglycol (NPG)–[x]wt.% d-camphor (DC), x=0, 3, 30, 46, 70 and 96 alloys on temperature and composition have been investigated by using radial heat flow apparatus. From graphs of the solid phases thermal conductivity variations versus temperature, the thermal conductivities of the solid phases at their melting temperature and temperature coefficients for NPG–[x] wt.% DC, x=0, 3, 30, 46, 70 and 96 alloys were found to be 0.29, 0.28, 0.27, 0.26, 0.25 and 0.24W/Km and 0.002996, 0.002694, 0.005690, 0.010626, 0.003520 and 0.001404K−1, respectively. The ratios of thermal conductivity of liquid phase to thermal conductivity of solid phase for NPG–[x]wt.% DC, x=0, 3, 30, 46, 70 and 96 alloys at their melting temperature were found with a Bridgman type directional solidification apparatus to be 1.07, 0.93, 0.43, 0.50, 0.40 and 0.35, respectively.

Toxicity of essential and non-essential oils against the chewing louse, Bovicola (Werneckiella) ocellatus

The toxicity of six plant essential oils to the chewing louse, Bovicola (Werneckiella) ocellatus collected from donkeys, was examined in laboratory bioassays. The oils examined were: tea-tree (Melaleuca alternifolia), lavender (Lavandula angustifolia), peppermint (Mentha piperita), eucalyptus (Eucalyptus globulus Labillardiere), clove bud (Eugenia caryophyllata) and camphor (Cinnamomum camphora). All except camphor oil showed high levels of toxicity, with significant dose-dependent mortality and an LC50 at concentrations of below 2% (v/v). Hundred percent mortality was achieved at concentrations of 5–10% (v/v). Two essential oil components: eugenol and (+)-terpinen-4-ol showed similar levels of toxicity. The data suggest that these botanical products may offer environmentally and toxicologically safe, alternative veterinary pediculicides for the control of ectoparasitic lice.

In-situ and real-time investigation of the columnar-equiaxed transition in the transparent alloy system neopentylglycol-camphor onboard the sounding rocket TEXUS-47

The low-gravity experiment TRACE (TRansparent Alloys in Columnar Equiaxed solidification) has been performed onboard the sounding rocket TEXUS-47 to enable the investigation of dendritic growth and the dendrites' columnar to equiaxed transition during solidification. Low-gravity conditions provide solidification under diffusive heat and mass transfer conditions and without sedimentation or buoyancy of equiaxed dendrites or nucleation seeds to simplify the boundary conditions for dendritic microstructure simulation. In addition the transparent organic alloy system Neopentylglycol (NPG) - (D)Camphor (DC) was used to allow for a real-time and in-situ observation of the microstructure evolution with standard optics. For the flight experiment all relevant experimental parameters like thermal gradient, solidification velocity and undercooling within the bulk liquid and at the columnar dendritic tips have been determined by image analysis or from thermocouple recordings within the solidifying alloy. This allows a very detailed comparison with results of existing models for dendritic growth and for columnar-to-equiaxed transition. Here we present a summary of the experimental findings in comparison with results of some of the theoretical models.

Novel Method: Coral Like Structure of Align Carbon Nanotubes (A-CNTs) on Porous Silicon Template (PSiT) without Catalyst; Green Approach

Align Carbon Nanotubes (A-CNTs) is very promising materials and offer attractive applications especially in opto-emission devices and nanoelectronic. Normally CNTs prepared by catalytic chemical vapor deposition using various types of template such as alumina, quartz, silicon and glass template. In this paper, Novel method was introduced to prepare A-CNTs which is combination between immersion and evaporation method. The align CNTs were successfully growth on Porous Silicon template (PSiT) without catalyst. Camphor oil is used as precursor and evaporation temperature is at 800 °C. The PSiT was prepared by photo-electrochemical anodization method. The surface morphology of PSiT layer and A-CNTs were studied using Field Emission Scanning Electron Microscope (FESEM).While Raman spectroscopy will be carried out to study the degree of crystallinity or graphitization of A-CNTs. The growth mechanism will be discussed in this paper. Stubby A-CNTs was successfully growth with 30 nm diameter and 250 nm length on PSiT without metal catalytic process. Meanwhile, this novel technique was found that PSiT is an ideal template for growing A-CNTs without metal catalyst assisted. This novel technique was capable to obtained carbon nanotubes without metal catalyst assisted and improves their purity of product with low cost.

Will P450cam Hydroxylate or Desaturate Alkanes? QM and QM/MM Studies

The hydroxylation versus desaturation for the enzyme P450cam is addressed by comparing the reactivity of the active species Por•+Fe(IV)═O (Cpd I) toward cyclohexane (CH), camphor (CAM), and cyclohexene (CHE). The quantum mechanics (QM)-only calculations, which reveal protein-free trends, show mixed and nonselective hydroxylation/desaturation activities, branching from the PorFe(IV)OH/R• intermediates. By contrast, the quantum mechanics/molecular mechanics (QM/MM) results with CAM and CHE show exclusive alcohol formation. Two distinct modes by which the protein controls the hydroxylation/desaturation selectivity were identified: (a) with the native substrate CAM, the tight binding site of the P450cam protein prevents the second hydrogen abstraction and leads to exclusive C5–H hydroxylation, and (b) with the freely tumbling CHE, the protein stabilizes the polarizable electromers, Por•+Fe(III)OH/R•, which possess intrinsic hydroxylase preference. The latter mechanism is common for substrates that are not tightly bound. It is a unique mechanism to P450 Cpd I, which possesses the Por•+Fe(III)OH electromers that dominate the in-protein reactivity. This is contrasted with nonheme enzymes, which lack such electromers.

Evaluation of the antifungal effects of rosemary oil and comparison with synthetic borneol and fungicide on the growth of Aspergillus flavus

Rosemary (Rosmarinus officinalis L.) with more than 240 active pharmacological and nutritional compounds is important from the botanical point of view. Pharmacological studies show the antifungal properties of Rosemary plant. The essential oil analyses of the aerial parts of rosemary collected from Kerman province were obtained using gas chromatography and gas chromatography mass spectrometry. The study of antifungal effects of the oil sample tested against strain of Aspergillus flavus (PTCC = 5004) fungi by disc diffusion method via average inhibition zone. The results showed that yield of Rosemary oil from Kerman province was 3.2%. Forty-one compounds were identified in the essential oil concluded as 99.74% of the total oil. The major components were α-pinene (15.52%), camphor (11.66%), verbenone (11.10%) and 1, 8-cineole (10.63%). The results showed that essential oil from rosemary plant at 1, 1/2 and 1/4 oil dilutions exhibited strong antifungal activity than gentamycin antibiotic on A. flavus and exhibited moderate of borneol was at 10% dilution. Benomil fungicide at 10% dilution had no inhibitory effect on A. flavus. Large percentage antifungal activities of Rosemary oil are related with α-pinene of monoterpenes as the main compound. Key words: Rosmarinus officinalis L., essential oil, Aspergillus flavus, aflatoxin, borneol.

The effect of antagonizing corticotropin releasing factor receptor 1/activating corticotropin releasing factor receptor 2 on visceral sensitivity and colonic motility of irritable bowel syndrome rats

Objective To explore the effect of corticotropin releasing factor (CRF) and its receptor on visceral sensitivity and colon motility of irritable bowel syndrome (IBS) rats. Methods sixty SD rats were divided randomly and equally into control group (without treatment),model group (sensitized in turn with camphor odor as conditional stimulation and physical restraint in combination with rectal distention pressure as non-conditional stimulation),treatment control group (injected physiological saline into lateral ventricles before treatment),treatment group 1 (injected CRF-R1antagonist into lateral ventricles before treatment),treatment group 2 (injected CRF-R2 agonist into lateral ventricles before treatment). Then the rats' visceral sensitivity were assessed by AWR,and colonic electricity activities such as volatility,maximum amplitude of fast wave and slow wave,interdigestive number of contraction wave and index of contraction were recorded. The data was analyzed with SPSS 16. 0 software. Results By the amount of ractal water injection to reach AWR=3 as the evaluation index,model group [(0. 90±0. 11) ml] showed higher visceral sensitivity than that of control group [(1. 23±0. 07) ml,F=82. 586,P＜0. 01],and colonic electricity activity increased (P＜0. 05),model was successfully set up. There was no significant difference of the amount of ractal water injection between model group [(0. 90±0. 11) ml] and treatment control group [(0. 81±0. 11) ml,F=3. 734,P＞0. 05]. Compared with treatment control group,the visceral sensitivity decreased in treatment group 1 [(1. 28±0. 07) ml,F=161. 878,P＜0. 01] and treatment group 2 [(1. 22±0.05) ml,F=121. 564,P＜0. 01]. There was no significant difference between treatment control group and model group in electricity activities such as volatility,maximum amplitude of fast wave and slow wave,interdigestive number of contraction wave and index of contraction (all P＞0. 05). While the electricity activities was weakened in treatment group 1 and 2 compared with the treatment control group (all P＜0. 05). Conclusions CRF plays an important role in the pathogenesis of IBS. Inhibition of CRF-R1 or activation of CRF-R2 may lower visceral hypersensitivity and decrease colon motility of rats. Key words: Irritable bowel syndrome; Receptors,corticotropin-releasing hromone; Visceral; Colon; Sensitivity and specificity; Colonic diseases,functional

Stress wave tomography for the quantification of artificial hole detection in camphor trees (Cinnamomum camphora).

The purpose of this study was to evaluate defects/holes in trees using a stress wave tomo-graphic technique. Results revealed that there was a significant positive relationship of the residual disc diameter ratio with the stress wave velocity, and a negative relationship with a reduction in the corresponding stress wave velocity in the virtual radial direction. A difference in the mapped color and stress wave velocity between the hole area and its surrounding sound area was obvious, and when the ratio of the hole area to the cross-sectional area exceeded 2.3%, the hole was detectable by tomography. A significant positive relationship between wood density and stress wave velocity of the transverse section was found in this study. Moreover, above the fiber saturation point, stress wave velocities tended to decrease with increasing moisture contents using tomography. Experimental results could provide some vital information for detecting defect locations and sizes in trunk cross-sections.

EVALUATION OF SOME NATURAL SUBSTANCES AGAINST VARROA DESTRUCTOR INFESTING HONEYBEE, APIS MELLIFERA IN EGYPT

This study was conducted to investigate the effect of certain natural substances against Varroa mite. Four natural substances (Apiguard and Thyme, Camphor and Basil oils) were evaluated in the field as control agents against the parasitic mite, V. destructor. Four treatments of each tested material were applied to each colony during the treatment period. . Data showed that all four tested compounds were effective in controlling Varroa and Apiguard was the most effective substance as they had an efficiency of 81.3%, 74.6%, 71% and 67%, respectively.

Carbon nanotubes formation from Fe/Ni/Mg by camphor oil decomposition

In this study, carbon nanotubes were formed from camphor oil decomposition on Fe/Ni/Mg catalysts at 650°C by fluidized floating catalyst method. X-ray diffraction (XRD) was used to examine the characteristics of carbon nanotubes. The carbon nanotubes were also examined both by FESEM and Raman spectroscopy to define their appearance and structure which revealed that dense bundle of mixed multi-walled and single-walled carbon nanotubes. The diameters of the single-walled carbon nanotubes were estimated to be around 0.86–2.31 nm. Little amount of carbon nanotubes were found on the Fe/Ni/Mg catalyst surface at 550°C; while a significant amount of carbon nanotubes were observed at 650°C. According to the XRD spectrum, there was carbon and graphite present in the deposited samples. Raman spectroscopy revealed two peaks at 1347–1357 cm−1 (D band, disorder mode, amorphous carbon) and 1572 cm−1 (G band, graphite sp2 structure). FESEM results indicated the Fe/Ni/Mg could catalyze the camphor oil decomposition to form carbon nanotubes even at a lower temperature.

Fumigant toxicity of volatile synthetic compounds and natural oils against red flour beetle Tribolium castaneum (Herbst) (Coleopetera: Tenebrionidae)

Two synthetic volatile compounds (benzaldehyde and propionic acid) and two volatile oils (camphor and eucalyptus) were screened individually and in combinations against different life stages of Tribolium castaneum. Benzaldehyde–propionic acid combination recorded the maximum larvicidal (LC50=78.03μl/l) and adulticidal (LC50=30.60μl/l air) activities and this treatment was also effective in reducing the oviposition, egg hatchability and adult emergence of T. castaneum. Among the individual treatments benzaldehyde was found to be more toxic to adults (LC50=34.07μl/l) and larvae (94.15μl/l). The individual treatments of camphor and eucalyptus oils were less effective, but combinations of benzaldehyde–camphor oil were found to be effective. Benzaldehyde–propionic acid combination recorded 99.3% adult mortality inside a 1m3 wooden cage after 15days and this mixture can be used as a fumigant in store houses.

FORMULATION, SPECIFICATIONS, EFFECTIVENES AND EVALUATION OF TESTED PLANT OILS AGAINST CERTAIN PLANT PATHOGIN FUNGI

A laboratory experiment had been conducted to throw light on the fungicidal activities of plant oils camphor oil, citronella oil and cotton seed oil against four species of fungi: P so/ant R. so/ant, S. roils// and T. virile These oils were prepared as emulsifiable concentrates (EC) using different surface active agents, namely: Sodium dodecyl sulphate, PEG 600 monolaurate, PEG 600 dioleate, Tween80 and Tween20, and solvents the xylene, isopropyl alcohol and dimethyl formamide. The physico — chemical properties for surface active agents, solvents, crude oils and prepared oils were measured. The bioassay experiments were designed to evaluate the EC50 for the plant oils against the fungi under investigation. Each plant oil was prepared in serial dilutions: 125, 250, 500, 1000 and 2000 pg/ml in PDA media. The results of bioassay showed that the response of the fungus S. rolfsii for all plant oils used was higher than other fungi under investigation. Also, the study showed that the fungus F. so/ani had more response to the plant oil citronella than for the other plant oils. On the other hand, the response of the fungi R. solani and T. virile to the plant oil camphor was higher compared to the other plant oils under investigation.

Chemical composition of the essential oil of two Iranian Satureja species (S. edmondi and S. isophylla)

Satureja genus presents 12 aromatic species in Iran, eight of which are endemic. Because of the several usages of Satureja species or their oils in different industries, we were interested to study the oil content and composition of Iranian Satureja species. In this research, the essential oil content and composition of two endemic species (S. edmondi and S. isophylla) were investigated. Essential oils from aerial parts of Satureja edmondi Briquet and Satureja isophylla Rech. f. were obtained by hydro-distillation. The oils were analyzed by capillary gas chromatography, using flame ionization and mass spectrometric detection. The components were identified with their mass spectrum and retention indices. Thirty components were identified in the oil of S. edmondi with p-cymene (61.1%), gamma-terpinene (9.6%), thymol (5.0%) and alpha-terpineol (4.8%) as main constituents. Fifty-six compounds were identified in the oil of S. isophylla with alpha-eudesmol (11.3%), beta-eudesmol (9.6%), camphor (7.1%), beta-caryophyllene (6.1%), gamma-eudesmol (5.8%) and geranial (5.5%) as main components. The results showed different composition of the essential oils of these Satureja species. The oil content and composition of these Satureja species were studied for the first time. We have studied some of the other Satureja species oils previously. This study showed the sharp differences between the oils of these two species with other Satureja species that will be presented compeletly.

Composition, radical scavenging and antifungal activities of essential oils from 3 Helichrysum species growing in Cameroon against Penicillium oxalicum a yam rot fungi.

The chemical composition of essential oils from leaves of Helichrysumcameroonense Hutch. and Dalziel, Helichrysum cymosum Sensu C. D. Adam, Helichrysum globosum Sch. Bip. ex A. Rich. and flowers of Helichrysumcameroonense was examined by means of GC and GC-MS. In addition, the radical scavenging and antifungal activities were assayed according to the DPPH (Diphenyl Picryl Hydrazyl) and dilution methods respectively. The results showed a predominance of monoterpenes in the oils of the leaves (89.5%) and flowers (62.9%) of H. cameroonense and of sesquiterpenes (58.0%) in that of H. cymosum. Extract from H. globosum was characterized by comparable proportions of monoterpenes (49.6%) and sesqiterpenes (49.1%). The major components were found to be a-pinene (46.4%) and camphor (11.5%) in the oil of leaves of H. cameroonense while a-pinene (31.4%) and guaienol (18.9%) were those from the flowers of the same specie. ∆-3-Carene (16.1%) and b-caryophyllene (12.0%) were the predominant compounds of the essential oils ofH. cymosum and a-pinene (36.6%), valerianone (10.9%) were those of H.globosum. The radical scavenging activities of essential oils from the leaves of H.cameroonense and H. cymosum were found to be 4.9 and 6.3 g/l respectively while butylated hydroxy toluene (BHT) used as reference has a SC50 =7.0 mg/l, On another hand, the essential oils from the leaves of these Helichrysum species showed significant antifungal activities against Penicillium oxalicum, with percent inhibition at 5 mg/ml ranging from 54.7 to 100%. These results highlight the potential of some essential oils as an alternative tool to fight this pathogen which is one of the most prevailing causing agent of soft rot of post harvest yam tuber. Key words: Helichrysum, Asteraceae, essential oil, radical scavenging activity, antifungal activity, Penicillium oxalicum, yams, Discoreaceae.

Preliminary investigation on nest-tree and nest-cavity characteristics of the Taiwan Barbet (Megalaima nuchalis) in Taipei Botanical Garden.

Taiwan Barbet (Megalaima nuchalis) is the only species of the Ramphastidae found in Taiwan and is endemic to the island. Megalaima nuchalis is found at low to mid elevations and is typically seen in the mid-canopy layer of broadleaf forests. During the breeding season, M. nuchalis excavates its own nest cavity in tree trunks or branches; therefore, it is closely associated with forests. From March to September of 2008, we investigated the characteristics of nest trees and nest cavities of M. nuchalis in Taipei Botanical Garden (TBG). The measured variables were nest tree species, tree height, tree diameter at breast height, nest height, tree diameter at nest, diameter of the cavity entrance, length of the horizontal passage, depth of the hole, and orientation of the cavity entrance. In total, we found 27 nest holes in 12 trees, which included 8 different tree species dominated by camphor (Cinnamomum camphora (L.) Presl). Megalaima nuchalis excavated nests in dead trees or in dead branches of living trees, and very few of the nest trees were monocotyledons. The nest cavities were found either on the main tree trunk or on side limbs, and the nest locations seemed to be related to the location of dead limbs on the nest tree and nest tree height. The shape of most cavity entrances was almost circular, and the size corresponded well to the body size of the birds themselves, as this prevents the invasion by natural enemies. The cavity entrances were mainly orientated towards the northwest to southwest, as these directions might have good air flow and could keep the nests well-ventilated and dry. The removal of dead trees and dead limbs from M. nuchalis habitats is disadvantageous during their breeding season. We recommend preserving dead trees and dead limbs which pose no danger in urban green areas as they provide nest cavities and resting holes for M. nuchalis and other secondary cavity nesters-in order to maintain and even enhance urban animal biodiversity.

Modified fluidised floating catalyst thermal CVD method for preparing carbon nanotubes using Fe/Co/Al

Carbon nanotubes (CNTs) have been successfully prepared at a low temperature of 650°C by using the fluidised floating catalyst method. Optimum concentration for Fe/Co/Al has been found to be around 0·75% for the best yield. Carbon nanotubes are produced from the evaporation of part of the precursor (camphor oil) which decomposes in situ and aggregates on the metal alloy catalyst particles present in the evaporating boat. Since the metallic alloy was obtained by calcining the respective nitrates, it is expected to have residual entrapped nitrogen which may bond with the depositing CNT. Fourier transmission infrared spectra confirm the presence of nitrogen in the prepared nanotubes which is stipulated to be embedded on the carbon surface in the form of C-N bonding instead of intercalating within the nanotubes.

THE INFLUENCES OF POWDER MIXING PROCESS ON THE QUALITY OF W-CU COMPOSITES

The mixing homogeneity of powders has a significant influence on the quality of composites fabricated from a powder metallurgy process. The factors that influence the homogeneity include the powder mixer, the medium, and the ball-milling procedure. In this paper, the influences of powder mixers and mixing media on the quality of tungsten-particle reinforced copper matrix composites are studied. Apart from dry mixing, other media used in the wet mixing process include n-butyl alcohol, camphor oil, and paraffin oil. Comparisons on mixing feature are made to a TURBULA® mixer and a Random mixer. The TURBULA® mixer is commercially available, and the Random mixer is an in-house designed machine. Our results show that using paraffin oil as the mixing medium, one may obtain optimal homogeneity in the composites. The Random mixer is superior to the TUBULA® mixer due to the fact that the Random mixer offers an avalanching motion creating pure shear forces onto the powders.