The efficacy of two ultrasonic units in shaping curved canals in teeth were compared. Twenty teeth were instrumented using the Cavi-Endo unit at a power setting 1 using the technique recommended by the manufacturer. Another group of 20 teeth received similar treatment but were instrumented with the Enac unit. The time taken to instrument each canal was recorded. The pre- and post-instrumented radiographs of the teeth of x 10 magnification were taken using a microfocal technique. The radiographs were subjected to a subtraction technique to result in composite images of the pre- and post-instrumented shapes. The canal shape and the incidence of elbows were evaluated using various measurements taken from the radiographs. The manner the dentine was removed was similar in both groups. All canals exhibited unequal removal along the canal with more dentine being removed at the coronal end. The Enac group exhibited a higher incidence of elbows which occurred further apically than those in the Cavi-Endo group. There was no significant difference between groups in the following: time of instrumentation, amount of apical and coronal canal enlargement, apical deviation and change in width at the elbow. These findings were no different from those of another study using simulated canals.
The resonant characteristics of ultrasonic files driven by the Cavi-Endo unit were examined. The investigation was carried out by evaluating the pattern of oscillation and the power emitted by the ultrasonic files. It was observed that the files oscillated in a sinusoidal fashion, exhibiting a standing wave pattern along the file. The power emitted was found to be directly proportional to the flexibility of the file. Such behaviour is typical of a system that exhibits resonance.
The temperature rise of the irrigant in the root canal during free vibration of the ultrasonic file was studied in vitro in 10 human teeth. The mean temperature rise was found to be 0.6 degrees C. The minimal temperature increase may not significantly contribute to the effectiveness of ultrasonic root canal instrumentation.
PIP: Responses to questions relating to breastfeeding in the World Fertility Surveys of South Korea, Indonesia, Nepal, Sri Lanka, Malaysia, and Bangladesh are analyzed. Of these countries, the percentage of ever-married women who had breastfed in the last closed interval was between 94-99%, except for Malaysia (81%) and average number of months breastfeeding took place was from 16.5-19.2, except for Malaysia (7.3). The infant mortality rate in these countries was 33/1000 live births for South Korea, 45/1000 for Malaysia, 51/1000 for Sri Lanka, 137/1000 for Indonesia, 150/1000 for Bangladesh, and 152/1000 for Nepal. Responses, however, might vary according to different interview situations. Assuming that the reporting errors are of similar magnitude and direction, the relationship between duration of breastfeeding and the birth interval can be studied. But it is possible that breastfeeding was prolonged due to other reasons for which conception was delayed; thus the regression of breastfeeding duration on the birth interval is not as logical as the regression of the birth interval on the breastfeeding is, especially when habitual breastfeeding can be avoided. The negative relationship between breastfeeding and infant mortality does exist, assuming that a woman breastfeeds all her children for similar durations. Some breastfeeding differentials are place of residence (less for rural areas), education (reduces duration), and religion (Christians have shorter duration than Muslims, Hindus, or Buddhists). In South Korea the mean length of breastfeeding of women aged 25-34 and 35-44 are 17.5 and 20.5, and women using contraceptives are 26% for 25-34 and 20% for 35-44. South Korea also has the highest level of breastfeeding, highest incidence of ever use of contraceptives, and a very low level of fertility. Nepal and Bangladesh have a high level of breastfeeding but since their contraceptive incidence is low, their fertility level remains high. Some areas of further research include influence of breastfeeding on infant and child mortality.
The present study was aimed to investigate the efficacy of fenugreek seeds as a potential natural source of antioxidants and antimicrobials. Fenugreek seed (FS) extracts were prepared using ethanol (75%), methanol (75%) and water as extraction solvents. Ethanol (E-FSP), methanol (M-FSP), water (W-FSP) and hot water (HW-FSP) extracts were obtained from ground FS, whilst water extract (W-GeFS) was obtained from germinated FS. The results revealed that all extracts of the ground FS exhibited antioxidant and antimicrobial activities and the extractability of bioactive compounds in the presence of water was higher in germinated seeds (W-GeFS). Highest phenolic (156.3 mg GAE/ g) and flavonoid (38.5 mg CE/ g) contents were found in W-GeFS. It also showed the strongest DPPH radical-scavenging activity of 68 % inhibition at a lower concentration (0.06 mg/ ml). In addition, highest vitamin C equivalent antioxidant capacity (143.28 mg vitamin C/ g) with an IC50 value of 42.1 μg/ ml were found in W-GeFS. Based on disc diffusion method, W-GeFS exhibited highest antimicrobial activity against all tested bacterial pathogens (Bacillus subtilis, Staphylococcus aureus, and Escherichia coli). Thus, it can be concluded from the results that W-GeFS extract from germinating fenugreek seeds (W-GeFS) has the potential to be used as a natural source of bioactive compounds with varied applications in food industry especially, for active film packaging purposes to prolong the shelf-life of food products.
Chrome azurol S immobilised on XAD-2 has been used in this study as a reagent phase for the development of an optical fibre Al(III) sensor. Using a kinetic approach, this sensor was able to give a linear response in the Al(III) concentration range of 1.3 x 10(-5)-2.0 x 10(-4) M with a limit of detection of 1.0 x 10(-4) M. The optimum responses were obtained at pH 6.0 and when the solution was stirred. The sensor response was found to have a repeatability and reproducibility of 1.6% and 5.8%, respectively. The results obtained for Al(III) determination in aqueous sample were in good agreement with those obtained using graphite furnace-atomic absorption spectrometry.
Many researchers documented that the stock market data are nonstationary and nonlinear time series data. In this study, we use EMD-HW bagging method for nonstationary and nonlinear time series forecasting. The EMD-HW bagging method is based on the empirical mode decomposition (EMD), the moving block bootstrap and the Holt-Winter. The stock market time series of six countries are used to compare EMD-HW bagging method. This comparison is based on five forecasting error measurements. The comparison shows that the forecasting results of EMD-HW bagging are more accurate than the forecasting results of the fourteen selected methods.
In this paper, the singular LR fuzzy linear system is introduced. Such systems are divided into two parts: singular consistent LR fuzzy linear systems and singular inconsistent LR fuzzy linear systems. The capability of the generalized inverses such as Drazin inverse, pseudoinverse, and {1}-inverse in finding minimal solution of singular consistent LR fuzzy linear systems is investigated.
An optical sensor for Hg(II) monitoring using a complex of zinc dithizonate immobilised on XAD 7 which is based on reflectance spectrophotometry has been developed in this study. Measurements were made using a kinetic approach whereby the reflectance signal is measured at a fixed time of 5 min. The sensor could be regenerated using a saturated solution of KCl in 1 M sulphuric acid. The sensor was found to have an optimum response at pH 3.0 with respective measurement repeatability and probe-to-probe reproducibility of 1.53% and 5.26%. A linear response was observed in the Hg(II) concentration range of 0.0-180.0 ppm with a calculated limit of detection (LOD) of 0.05 ppm. The results obtained for aqueous Hg(II) determination using this probe were found to be comparable with the well-established method of atomic absorption spectrometry.
Gallocynin immobilized in chitosan membrane has been studied as a sensor element of an optical sensor for lead using a flowing system. By using this set up, lead in solution has been determined in the concentration range from 1.0x10(-1) to 1.0x10(3) ppm with a detection limit of 0.075 ppm. The standard deviation of the method for the repeatability of lead detection at a concentration of 100 ppm was found to be 2.10%. The response of the sensor was reproducible and can be regenerated by using acidified saturated KNO(3) solution. Interference from foreign ions was also studied at 1:1 mole ratio of Pb(II):foreign ions.
A flow-through optical fibre chemical sensor for the determination of Co(II) at trace level using immobilised 2-(4-pyridylazo)resorcinol (PAR) as the reagent phase is proposed. PAR is physically adsorbed onto XAD-7. This method provided a great sensitivity and simplicity with wide linear response range from 1x10(-2) to 1x10(3)ppm and detection limit of 20ppb. This method also showed a reproducible result with relative standard deviation (R.S.D.) of 1.78% and response time of approximately 5min. The response towards Co(II) was also reversible using acidified KCl as the regenerating solution. Interference studies showed that Cr(III) significantly interfered during the determination. Excellent agreement with reference to inductively coupled plasma optical emission spectroscopy (ICPOES) method was achieved when the developed sensor was applied for determination of Co(II) in aqueous samples.
The incidence of breakage of Piezon-Master ultrasonic K files were evaluated. Three groups of unused files were subjected to three treatments, namely; free vibration in air without irrigation, free vibration in root canal while minimizing contact with the wall of canal in the presence of irrigation and light filing in root canal with free flow of irrigation. Cavitation produced by files in contact and free of contact with a glass surface was examined in order to observe the relationship between cavitation defects and breakage. In addition, the fractured and unfractured files were examined under a scanning electron microscope for the presence of cavitation pits. The results indicated that more files broke in air. In water, a higher incidence of breakage occurred when files were allowed to freely vibrate while no breakage occurred when the files were used in filing. All files generated cavitation which resulted in pitting of their surfaces. However, it was considered unlikely that the pits contributed to fracture. Fatigue cracks which could be the result of the manufacturing process were observed at some of the corners of the cross sections of the fractured files and could be the main contributory factor to fracture.
Penilaian status visual kanak-kanak prasekolah adalah penting kerana ia adalah salah satu faktor yang menentukan ketersediaan mereka untuk bersekolah. Walau bagaimanapun, tidak semua kanak-kanak prasekolah mendapat peluang untuk mengikuti program saringan penglihatan. Dalam kajian ini, akuiti visual jauh dan dekat serta tahap stereoakuiti diukur di kalangan kanak-kanak berumur enam tahun (n=385). Parameter tersebut kemudiannya dibandingkan di antara kanak-kanak prasekolah swasta bandar dan prasekolah KEMAS daripada keluarga berpendapatan rendah di luar bandar. Tujuh peratus kanak-kanak prasekolah KEMAS adalah gagal dalam ujian saringan penglihatan jauh berbanding dengan 6% kanak-kanak prasekolah swasta. Untuk ujian penglihatan dekat, kadar kegagalan adalah masing-masing 8.7% dan 4.9% bagi kanak-kanak prasekolah swasta dan KEMAS masing-masing. Untuk ujian stereoakuiti, seramai 3.3% kanak-kanak prasekolah swasta dan 2.5% kanak-kanak prasekolah KEMAS dikategorikan sebagai lemah stereopsis. Semua perbezaan tersebut adalah tidak signifikan secara statistik (semua p>0.05). Peratusan kanak-kanak yang gagal ujian saringan penglihatan adalah serupa untuk kedua-dua jenis prasekolah. Oleh itu, program saringan penglihatan perlu dijalankan di semua jenis prasekolah untuk memastikan sebarang masalah penglihatan dapat dikesan, didiagnos, dirawat dan dicegah.
Psychotherapies were offered to alleviate psychological and physical symptoms; however, most psychological interventions were only delivered after cancer treatment. Newly diagnosed cancer patients experienced psychological distress while waiting for treatments. This review paper focused on randomized control trial studies, aimed to investigate the effectiveness of psychological intervention among newly diagnosed cancer patients. Eight randomized control trial papers were found in recent 10 year period through electronic database. A moderate to large effect size was detected on the outcomes, ranging from 0.43 to 0.89. This indicated that psychological-based prehabilitation with standard care yielded better outcomes than standard care alone. Psychological-based prehabilitation provides evidence in its effectiveness to reduce psychological distress, functional impairment, recurrence of cancer, numbers of immune reactivity and sleeping quality; however, inconsistent with longer survival result among cancer patients. In conclusion, psychological-based prehabilitation before cancer treatment is necessary for better treatment outcome, and future research is needed to investigate more directly the outcome.
Shale rock swelling poses a significant challenge during drilling a well, leading to issues related to wellbore instability. Water-based mud with specific shale inhibitors is preferred over oil-based drilling mud due to its lower environmental impact. Recently, ionic liquids (ILs) have emerged as potential shale inhibitors due to their adjustable properties and strong electrostatic attraction. However, research has shown that the most commonly used class of ILs (imidazolium) in drilling mud are toxic, non-biodegradable, and expensive. Deep Eutectic Solvents (DESs), the fourth generation of ionic liquids, have been proposed as a cheaper and non-toxic alternative to ILs. However, ammonium salt-based DESs are not truly environmentally friendly. This research explores the utilization of Natural Deep Eutectic Solvent (NADES) based on Epsom salt (a naturally occurring salt) and glycerine as a drilling fluid additive. The drilling mud is prepared according to API 13B-1 standards. Various concentrations of NADES-based mud are tested for yield point, plastic viscosity, and filtration properties for both aged and non-aged samples. The linear swell meter is used to determine the percentage swelling of the NADES-based mud, and the results are compared with the swelling caused by KCl- and EMIM-Cl-based mud. FTIR analysis is conducted to understand the interaction between NADES and clay, while surface tension, d-spacing (XRD), and zeta potential are measured to comprehend the mechanism of swelling inhibition by NADES. The findings reveal that NADES improves the yield point and plastic viscosity of the mud, resulting in a 26% reduction in mudcake thickness and a 30.1% decrease in filtrate volume at a concentration of 1%. NADES achieves a significant 49.14% inhibition of swelling at the optimal concentration of 1%, attributed to its ability to modify surface activity, zeta potential of clay surfaces, and d-spacing of clay layers. Consequently, NADES emerges as a non-toxic, cost-effective, and efficient shale inhibitor that can replace ILs and DESs.
A biosensor for measuring the antidiabetic potential of medicinal plants was developed by covalent immobilization of α-glucosidase (AG) enzyme onto amine-functionalized multi-walled carbon nanotubes (MWCNTs-NH2). The immobilized enzyme was entrapped in freeze-thawed polyvinyl alcohol (PVA) together with p-nitrophenyl-α-D-glucopyranoside (PNPG) on the screen-printed carbon electrode at low pH to prevent the premature reaction between PNPG and AG enzyme. The enzymatic reaction within the biosensor is inhibited by bioactive compounds in the medicinal plant extracts. The capability of medicinal plants to inhibit the AG enzyme on the electrode correlates to the potential of the medicinal plants to inhibit the production of glucose from the carbohydrate in the human body. Thus, the inhibition indicates the antidiabetic potential of the medicinal plants. The performance of the biosensor was evaluated to measure the antidiabetic potential of three medicinal plants such as Tebengau (Ehretis laevis), Cemumar (Micromelum pubescens), and Kedondong (Spondias dulcis) and acarbose (commercial antidiabetic drug) via cyclic voltammetry, amperometry, and spectrophotometry. The cyclic voltammetry (CV) response for the inhibition of the AG enzyme activity by Tebengau plant extracts showed a linear relation in the range from 0.423-8.29 μA, and the inhibition detection limit was 0.253 μA. The biosensor exhibited good sensitivity (0.422 μA/mg Tebengau plant extracts) and rapid response (22 s). The biosensor retains approximately 82.16 % of its initial activity even after 30 days of storage at 4 °C.
Ti-doped ZnO nanorod arrays were grown onto Si substrate using chemical bath deposition (CBD) method at 93 °C. To investigate the effect of time deposition on the morphological, and structural properties, four Ti-doped ZnO samples were prepared at various deposition periods of time (2, 3.5, 5, and 6.5 h). FESEM images displayed high-quality and uniform nanorods with a mean length strongly dependent upon deposition time; i.e. it increases for prolonged growth time. Additionally, EFTEM images reveal a strong erosion on the lateral side for the sample prepared for 6.5 h as compared to 5 h. This might be attributed to the dissolution reaction of ZnO with for prolonged growth time. XRD analysis confirms the formation of a hexagonal wurtzite-type structure for all samples with a preferred growth orientation along the c-axis direction. The (100) peak intensity was enhanced and then quenched, which might be the result of an erosion on the lateral side of nanorods as seen in EFTEM. This study confirms the important role of growth time on the morphological features of Ti-doped ZnO nanorods prepared using CBD.
Keratitis is corneal inflammatory disease which may be caused by several reason such as an injury, allergy, as well as a microbial infection. Besides these, overexposure to ultraviolet light and unhygienic practice of contact lenses are also associated with keratitis. Based on the cause of keratitis, different lines of treatments are recommended. Photodynamic therapy is a promising approach that utilizes light activated compounds to instigate either killing or healing mechanism to treat various diseases including both communicable and non-communicable diseases. This review focuses on clinically-important patent applications and the recent literature for the use of photodynamic therapy against keratitis.
There is an increasing trend among pharmaceutical industries to use natural bioactive materials as medicinal agents and to use new technologies such as self-nanoemulsifying systems. The solubility and bioavailability of poorly soluble drugs can be enhanced by self-nanoemulsifying systems. Swietenia oil is frequently used because of its antimicrobial, antimutagenic, and anticancer bioactive medical properties. This study was conducted to develop self-nanoemulsifying systems for Swietenia oil that will enhance the anti-inflammatory activity of the oil. The self-emulsifying systems developed for Swietenia oil in this study were constructed using ternary phase diagrams and contained the nonionic surfactants Labrasol(®), Tween 20, Capmul(®), and Labrafil(®). The effect of these surfactants on the formulation was examined. The mean droplet size of Swietenia oil as well as their distribution, appearance, viscosity, and spreading times were studied to find the optimum formula, which contained droplets that were less than 200 nm. The next step was to test the anti-inflammatory properties of the optimum formula using a carrageenan-induced rat paw edema test. The results from this test were compared to the oil solution. Different oil/surfactants mixtures had various emulsification properties that were related to the size of their droplets. Tween 20 is a good surfactant to use in self-emulsifying systems because it produces droplets of nano-size. Mixtures of Capmul/Labrasol at a ratio of 2:1 and Labrafil/Tween 20 at a ratio of 1:2 were able to produce self-nanoemulsifying formulations containing Swietenia oil concentrations that ranged from 20%-50%. Nanoemulsion occurred when the size of the droplets fell below 200 nm with low size distribution (<0.3) after being gently mixed with water. It was found that the hydrophilic/lipophilic balance value affected the ternary phase diagram behavior of Swietenia oil and surfactants. In addition, the anti-inflammatory properties of Swietenia oil were greater in the self-nanoemulsifying systems than in the oil solution.