A pH Switchable Responsive Surface for the Trapping And Release of a Hydrophobic Substance

Solid phase extraction is one of the most widely used techniques to trap and release compounds in a solution. A hydrophobic substance will stick efficiently to a hydrophobic surface (the “like dissolves like” principle). With an introduced response (i.e. pH change), a responsive surface can change from hydrophobic to hydrophilic, weakening the hydrophobic substance’s attraction and thus facilitate in an easy removal. A surface has been prepared having a terminal anthranilic acid (AA) moiety on silica gel particles, microscope slides, and TLC plates in three steps. First, a vinyl group was attached to the surface. Then, this vinyl group was reacted to form a surface carboxylic acid group. Finally, the carboxylic acid group was converted to an amide group that linked to the silica surface. FT-IR, and elemental analysis were used to confirm each step of the synthesis. At low pHs the –COOH group on the AA moiety is neutral and intrahydrogen bonding keeps this moiety’s phenyl (hydrophobic) portion exposed to the surface. The effect has been investigated by measuring contact angles at various pH values. At higher pHs the AA’s carboxylic acid group becomes the charged carboxylate, rendering the surface hydrophilic. Substances can be trapped and released using this unique switching approach. 2-naphthol, for example, is hydrophobic and thus was trapped at lower pHs (pH 4) (hydrophobic surface) and released at higher pHs (pH 10) (hydrophilic surface) on this responsive surfac

Effect of Magnetic Field From Mobile Phone on Brain

Human exposure to electromagnetic field (EMF) comes from many different sources and occurs in various situations in everyday life. Man-made static fields are mainly found in occupational settings, such as close to magnetic resonance imaging (MRI) scanners, although DC high-voltage overhead transmission lines are being constructed, which are expected to expose larger parts of the population to static electric and magnetic fields.Today, for power regulation most modern electrical equipment uses electronics instead of transformers. Examples include the switched power supplies to laptops, drilling tools, chargers of mobile phones and similar devices. As a consequence, the frequency content of the daily magnetic field exposure has changed mainly by adding odd harmonics (150 Hz, 250 Hz, 750 Hz, etc.). In particular, the third harmonic (150 Hz) has become another dominating frequency in our environment.In particular for brain tissues, the mobile phone used at the ear remains the main source of exposure. However, since the first generation of mobile telephony, the technology aimed at reducing the emitted power of mobile handsets. In particular, for Global System for Mobile communication (GSM) already the introduction of dynamic power control reduced the average output power to about 50% of its rated value during calls, whereas the use of discontinuous transmission during voice calls gave a further 30% reduction in average emitted power. Adaptive power control became faster and more effective in the third-generation (3G) of mobile telephony systems leading to a further reduction (by about two orders of magnitude) in the specific absorption Specific energy Absorption Rate (SAR) compared to GSM phones. In addition, hands-free kits reduce the energy absorbed by the head drastically. Digital Enhanced Cordless Telecommunications (DECT) phones are another source of everyday exposure

EFFECT OF MAGNETIC FIELD FROM MOBILE PHONE ON CENTRAL NERVOUS SYSTEM

Devices such as mobile phones, wireless internet modems, and radios and televisions, which occupy an important place in social life, produce electromagnetic fields (EMFs). Widespread use of these devices in daily life increases the intensity of exposure to EMFs on a day to day basis. Investigation of the effects on health of devices such as mobile phones used in close proximity to the body is attracting considerable interest from scientists. Mobile phones manufactured using the latest technology operate in a high frequency range (3003000 MHz). This further heightens concerns regarding the effect of mobile phones on human health. Most Global System for Mobile Communications (GSM) operators in Europe, Asia, and Africa use a frequency of 900 MHz. With the rapid development of electronic information and communication techniques, exposure to electromagnetic fields (EMFs) has increased dramatically. Some studies have focused on the biological effects of electromagnetic radiation. Microwave radiation has been reported as producing adverse effects in the central nervous system (CNS), including headache, sleep disorders, anxiety, cognitive dysfunction and neurogenesis impairment in both humans and animals. However, the direct effects of microwave radiation on neurodevelopment and the underlying mechanisms for any such effects remain unknown. As per todays global scenario use of mobile phone is increasing day by day for communication. Due to its constant use, the electromagnetic radiation (EMR) emitted from the cell phone, base station and other household appliances cause adverse effects on human health. There is an increase concern about the interaction of EMR generated from mobile phones, with the human organs specially with brain because of its close and long proximity to human brain during the mobile usage. Concerns have shown whether these exposures could have effect on brain and central nervous system (CNS)

MEDICINAL VALUE OF LAGERSTROEMIA SPECIOSA: AN UPDATED REVIEW

Lagerstroemia speciosa (Family: Lythraceae) is native to Asia-tropical and subtropical regions. The phytochemical investigation of Lagerstroemia speciosa leaf and fruit revealed that it contained steroids, terpenoids, glycosides, phenolic compounds, α-amino acids, saponins, starch, alkaloids, carbohydrates, organic acids, flavonoids, reducing sugars, tannins and many other active metabolites. Lagerstroemia speciosa possessed many Pharmacological effects included antimicrobial, antioxidant, anticancer, antidiabetic, hypolipidemic, antiobesity, anti-inflammatory, analgesic, gastrointestinal, diuretic, thrombolytic, cardiovascular, central nervous, inhibition of TNFα production, xanthine oxidase inhibitition, hepatoprotective and nephroprotective effects. The current review discussed the chemical constituents, pharmacological and therapeutic effects of Lagerstroemia speciosa

Constituents and Pharmacological Effects of Leontice Leontopetalum- A Review

Phytochemical analysis showed that Leontice leontopetalum contained many quinolizidine alkaloids, tannins, phenolic,  flavonoids  and many other bioactive contents. The pharmacological studies revealed  that Leontice leontopetalum possessed antioxidant, antidiabetic, convulsant and anti convulsant, cytotoxic, anticholinesterase cardiovascular and smooth muscle contractile effects. The current mini review discussed the chemical constituents and pharmacological effects of Leontice leontopetalum

Melatonin production influenced by low frequency magnetic fields

In several residential and occupational studies, suppression of nocturnal melatonin in humans, which is induced by magnetic field, has been reported. The pineal gland produces melatonin and consider it as its major secretory product, which has a vital role in human well-being and health as it was suggested by the growing literature. Generally, exposure to the electric field has many biological effects, and the research on which has recently made this neurohormone, which is associated with the generation and classification of electric field, a focal point. To raise the risk of cancer through changing the pineal glands' regular functions and disrupting the melatonin's nocturnal increase in its release and synthesis, exposure to magnetic fields has been hypothesized. It is very essential to ascertain whether hormonal levers are changed during the exposure of humans to a magnetic field at night because the evidence for the "melatonin hypothesis" relies chiefly upon rodent data. The field-induced alterations were failed to be observed by all studies which have investigated the alterations in melatonin under controlled laboratory conditions when humans are exposed to a magnetic field. However, melatonin levels are altered through the exposure to low frequency magnetic fields, as it has been proposed by several observational studies in occupational and residential settings, which usually differ in terms of the presence of possible confounders, the individuals' health status and their general characteristics, the exposure conditions, and the attained measurement's precisions, durations and types. The associated differences in the duration of exposure may lead to this model of conflicting results. In the laboratory studies, only one night of exposure to a magnetic field was received by volunteers. In contrast, participants in the observational studies, usually for long periods on a daily basis, received chronic exposures to such fields. The consistent measurements of each melatonin over time is considered as another related possible explanation. It is unknown if the frequent magnetic field exposures suppress the inherent stability of each measurement of melatonin over time. In conclusion, the explanation of the contrasting results obtained in laboratory studies, and not in observational ones, could be helped by the evidence for improved suppression or increased variable measurements of melatonin attained in studies with longer controlled exposures

Medical Benefit of Lallemantia Iberica- A review

Lallemantia iberica (Family: Lamiaceae) is used traditionally   as stimulant, diuretic, expectorant, in the treatment of common cold, coughing, stomach  and abdominal pain. It produced many secondary metabolites such as phenolic acids, flavonoids, tannins, triterpen, mucilage and oil. It possessed many pharmacological effects included analgesic, antibacterial and antioxidant effects. The current review discussed the chemical constituents and pharmacological effects of Lallemantia iberica

CHEMICAL CONSTITUENTS AND PHARMACOLOGICAL EFFECTS OF LEPIDIUM SATIVUM-A REVIEW

Lepidium sativum contained many bioactive constituents included cardiac glycoside, alkaloids, phenolic, flavonoids, cardiotonic glycosides, coumarins, glucosinolates, carbohydrates, proteins and amino-acids, mucilage, resins, saponins, sterols, tannins, volatile oils, triterpene, sinapic acid and uric acid. The pharmacological investigation revealed that Lepidium sativum possessed antimicrobial, antidiabetic, antioxidant, anticancer, reproductive, gastrointestinal, respiratory, anti-inflammatory, analgesic, antipyretic, cardiovascular, hypolipidemic, diuretic, central nervous, fracture healing and protective effects. The current review discussed the chemical constituents and pharmacological effects of Lepidium sativum

A REVIEW ON LAWSONIA INERMIS: A POTENTIAL MEDICINAL PLANT

Lawsonia inermis (Family: Lythraceae) contained carbohydrates, phenolic, flavonoids, saponins, proteins, alkaloids, terpenoids, quinones, coumarins, xanthones, fat, resin and tannins. It also contained 2-hydroxy-1,4-naphthoquinone (lawsone). Many alkaloids, naphthoquinone derivatives, phenolics and flavonoids were isolated from different parts of Lawsonia inermis. The pharmacological studies showed that Lawsonia inermis showed antibacterial, antifungal, antiparasitic, molluscicidal, antioxidant, hepatoprotective, central nervous, analgesic, anti-inflammatory, antipyretic, wound and burn healing, immunomodulatory, antiurolithiatic, antidiabetic, hypolipidemic, antiulcer, antidiarrhoeal, diuretic, anticancer and many other pharmacological effects. The current review will highlight the chemical constituents and pharmacological effects of Lawsonia inermis

Pattern reconfigurable metamaterial antenna for 5G base station network

Reconfiguration of an antenna’s radiation pattern in a predefined direction is very important for enhancing the performance of communication systems in terms of the quality of service, system security, avoiding interference, and economizing power. Metamaterials, on the other hand, are commonly used in antenna design to enhance the gain, bandwidth, and efficiency and recently to tilt the radiation beam. Nonetheless, few issues had been encountered especially when the frequency is pushed to higher range such as the inherent losses that restrict the variety of their applications. Hence, metamaterials structures with relatively low loss are in high demand. In this thesis, various metamaterial structures with low loss properties are proposed. Then these structures are reconfigured and integrated with the fifth-generation (5G) planar antennas at two different frequency bands i.e. millimetre-wave (MMW) band and sub-6 GHz band for beam deflection applications. The modified double square ring resonator (DSRR) and contiguous squares resonator (CSR) structures are investigated numerically and experimentally to provide low loss property at 76 GHz and around 28 GHz, respectively. DSRR and CSR achieve losses of 0.5 dB and 0.2 dB, respectively. Both structures are manufactured and measured to validate the results. Furthermore, the analytical model is introduced to predict the electromagnetic behaviour of the proposed metamaterial structures. Thereafter, the CSR, Bridge shaped resonator (BSR) and split square resonator (SSR) structures are electronically reconfigured to produce different refractive indices at MMW and sub-6 GHz spectrums, which are used for deflecting the radiation beam of the 5G planar antennas. An array of unreconfigurable adjacent square-shaped resonators (ASSRs) has been also used for tilting the radiation pattern of planar antenna at sub-6 GHz spectrum. These proposed structures are included in the substrate of the dipole antenna and bow-tie antenna for deflecting the radiation pattern in E-plane at two different 5G bands of 28 GHz and 3.5 GHz. The results of all designs at both bands show that the radiation beam of the antennas is deflected in both positive and negative directions with respect to y-direction of antenna. At 28 GHz, a high deflection angle of 34° is obtained using simple structure, BSR, with gain improvement up to 1.9 dB (26.7%). On the other hand, at 3.5 GHz, the beam deflection angle of ±39º is achieved with gain enhancement up to 2.4 dB (35.6%) using passive beam deflection antenna whereas the beam deflection of ±36º is obtained using an active beam deflection antenna. The reconfigurable metamaterial antennas are proposed to be used in 5G base station network with advantages of high deflection angles, gain enhancement, low profile structure, low cost, lightweight, and easy integration with other circuits for 5G beam deflection applications