p-HBTF copolymer have been synthesized and agar diffusion method was employed to study their antibacterial activity (Fig.8). Test bacterial pathogens used in this study includes B. Subtilis , E. Coli , S. Typhi The antibacterial screening of p-HBTF is analysed at BIOGENICS, Hubli (Karnataka). Initially, the stock cultures of bacteria were revived by inoculating in broth media and grown at 37ºC for 18 hrs. The agar plates of the above media were prepared and wells were made in the plate. Each plate was inoculated with 18 h old cultures (100 µl, 10 4 cfu) and spread evenly on the plate. After 20 min, the wells were filled with different concentrations of samples. The control wells were filled with Gentamycin. All the plates were incubated at 37ºC for 24 h and the diameter of inhibition zones were noted. Test samples were tested at different concentration to test their efficacy in inhibiting the growth of the human pathogens.
p-NP-4,4’-ODA-F-I copolymer has been synthesized by condensation of p-nitrophenol (2.78 gm, 0.2 mol), 4,4’-oxydianiline (2 gm, 0.1 mol) and formaldehyde (11.25 ml, 0.3 mol) with the molar proportion of 2:1:3 in presence of 2 M hydrochloric acid (200ml) as a catalyst. Reaction was carried out in a round-bottom flask fitted with a water condenser and heated at 130 0 C in an oil
The nanostructuration observed is coherent with the computer simulation of the phase diagram of random copolymers carried out by Houdayer and Muller . Based on our knowledge, this is the first time that the nanostructuration of a P(DLLA-co-CL) copolymer is reported. Moreover, very few experimental demonstra- tions of the nanostructuration of random copolymers have been reported in the scientific literature [28,29]. Taking into account the small amount of PCL, less than 15 mol%, it is assumed that spherical CL- enriched domains have been obtained. In this case, we consider that, because of the chemical nature of the copolymer, the higher affinity of chloroform for CL than for LA (as obtained by the solubility parameters calculated by the Hoftyzer and van Krevelen theory ) has favored the phase separation of CL-enriched domains in a matrix of pure LA or of LA with a lower CL content.
The yields of polymerization of the homopolymer and copolymer hydrogels were found to be above 90%.The swelling values were determined at appropriate time intervals. For pure PHEMA hydrogel, the water uptake is 243% which was 6 times than that reported in the literature review. And it was decreased for P(HEMA-MMA) hydrogel due to hydrophobicity of MMA to about 1.27 times from that of PHEMA The mechanical properties such as tensile strength and hardness were studied on the homopolymer and copolymer hydrogels. The pure PHEMA hydrogel showed the tensile strength of 0.52 kg/cm 2 which is very low. The tensile strength of P(HEMA-MMA) hydrogel increased from 0.38 kg/cm 2 to 9.03 kg/cm 2 with the increase in contents of MMA from 5% to 20% in which MMA was a conventional strengthening monomer. Incorporation of MMA upto 10% in HEMA monomer decreased the strength one fold and further incorporation of higher concentrations of MMA alone increased the strength upto 17 times.
In this research, we have developed a process for cova- lently coating MNPs with PNIPAAm and P(NIPAAm- MAA-VP). We have shown that these PNIPAAm-MAA- VP-coated MNPs have a LCST above body temperature and functional groups on their surface for conjugation of biomolecules . Also we intend to investigate the in vitro characteristics of our nanoparticles for drug deliv- ery applications. To manufacture the PNIPAAm-MAA- VP-coated MNPs, NIPA, MAA, and VP were then po- lymerized the MNPs via methylene-bis-acrylamide and benzoil peroxid (BP) as a cross-linking agent and an ini- tiator, respectively. The nanoparticle size and morphology were analyzed using scanning electron microscopy (SEM). The drug release behavior of doxorubicin DOX, an anti- cancer drug model from the nanoparticles at temperatures below and at the LCST was also analyzed. Furthermore, it would be possible to image the cancer in vivo and dis- cern the effect of the therapy on the tumor . This type of multifunctionality (ability to image and provide ther- apy) in MNPs has recently been gained interest .
of OEG macromonomers is functionalized at one ter- minal only, and for most of which methacrylate is used as the terminal groups, whereas for the comonomers of low molecular weight, a variety of (meth)acrylates and acrylamide are used and MAA is rarely used [3, 13–17]. To prepare a novel type of OEG-based thermoresponsive polymers, a new type of OEG with both terminals functionalized with acrylate (OEGDA) was copolymer- ized in water with MAA, also a rarely used monomer (see Additional file 1: Figure S1). The polymerization was done with 40% of OEGDA in moles. The com- position of the obtained P(OEGDA-MAA) was ana- lyzed by 1 H NMR (Fig. 1). The assignments of the peaks were carried out based on those of the mono- mers used (see Additional file 1: Figure S2) and on the reported polymers with similar structures . The group of the peaks at chemical shift of 1.2 ppm or lower zone was assigned to the methyl protons in MAA unit in the polymer; the large and sharp peak at 2.0 ppm was assigned to the protons in the main chain consisting of MAA and acrylic segments, while the group of the large peaks appeared from 3.2 to 3.9 ppm was assigned to the protons of the ethylene of the backbone. The characteristic peaks, at chemical shifts of 12.35 and 4.11 ppm (Fig. 1) attributed to the carboxylic proton of MAA (Ha) and the oxyethylene ester protons (Hb) immediately adjacent to the acryl- ate units, were used to estimate the composition of
10 Read more
polymer); therefore, the homopolymer shows a unique switch temperature. In contrast, NIPAAm can take many chemical environments in a copolymer, e.g., -BA-NIPAAm-BA-, -BA- NIPAAm-NIPAAm-BA-, -BA-NIPAAm-NIPAAm-NIPAAm- BA-, etc. Therefore, the switch temperature can be considered to be distributed over wide temperature range as compared with the homopolymer. For the later result (decreasing average value of switch-temperature), the hydrophobic character of BA is thought to influence the switch-temperature. It is reported that P(NIPAAm) assumes globular and coiled conformations in aqueous solution at low and high temperatures, respectively. Water molecules can link to the hydrophilic part of -CO-NH- and prevent aggregation of the hydrophobic regions in NIPAAm at low temperatures (Stillinger 1980; Sun et al., 2008; Crassous 2008; Mackiewicz 2014; Speˇvácˇek et al., 2014; Ishida et al., 2007; Ishida et al., 2007). In the copolymer, it can be considered that increasing the BA components promotes aggregation of the hydrophobic regions in NIPAAm and BA, and the copolymer has low transition temperatures. The present DSC results suggest that the average switch-temperature of the copolymer of NIPAAm-co-BA (0.90:0.10), which was employed for the outdoor measurement (results are presented in Fig. 10), was ca. 20°C. Therefore, if the ambient temperature were to fall below 20°Con a summer night, more water molecules would be adsorbed on the coating materials and cooling effects would be observed in the afternoon, as shown in Fig. 9. In order to evaluate the water resistance, a wall was coated with the copolymer. After drying, the wall was washed withD 2 O (NMR solvent). However, no
The VP-6124 and VP-6124-E are fully regulated 24VDC, 6 Amp switching power supplies. The primary is protected by a 4 Amp slo-blow fuse and the 2 Amp outputs by auto resetting fuses. The outputs are floating with respect to ground. The regulator will maintain 24 Volts +/-2% over the rated range of input voltages and output loads. A greater than 6 Amp load on power up will cause the power supply to current limit. Short circuit protection is provided. Over voltage is provided to limit the output voltage to approximately 28 Volts should a failure occur within the power supply. Outputs may be paralleled but not series connected.
In conclusion, the high importance of MAA as an accurate, rapid, sensitive and specific marker for identification of milk quality and also subclinical mastitis has been reported. Furthermore, we considered that the concentration of MAA can be a useful indicator of mammary gland inflammation and unfavorable changes in milk quality in cow; although a clear and standardized cut- off value for the healthy udder-half should be confirmed. These results encourage further study of the MAA physiology in other animal species. Using three different concentrations of MAA is practical approach to study the quality of bulk tank milk samples. The advantage of MAA over other mastitis markers is attributable to the fact that it is not present in the milk of healthy animals and is not influenced by factors other than mastitis. Therefore, MAA estimation in milk is a useful diagnostic method to detect subclinical mastitis especially in bulk tank milk samples to monitor herd health. Therefore, the online measurement of MAA with automated milking systems can enable early detection of mammary inflammation and infection, reduce the economic loss and improve the health and welfare of dairy herds as well as public health.
Since discontinuous constituents are a typical manifestation of free word order, we can summa- rize that the word order freedom within Bulgarian VP is a result of different information packaging. The constraints on word order, though, come from semantics. This means that whenever adjuncts with narrow sematic scope are realized within VP, their semantics poses restrictions on word order since the adjunct has to be realized in contact to the ele- ment of the VP it semantically modifies. The reali- zation of the adjunct in contact to the element it modifies semantically (in pre- or postposition to
There was considerable amount of facial asymmetry in both group 1 and 2 as shown in Table 6. Paired samples test was applied to find the level of statistical significance between the measures of the right and left sides among group 1 participants. The following parameters were found to be statistically significant: Condyle to Menton (Co-Me), Chin to O point (Ch - O pt), Gonion to Vertical plane (Go-VP), Condyle - Antegonion - Menton angle (CO-Ago-Me) O point - Chin - Chin’ angle (O-Ch-Ch’) as shown in Table 7.
Virtual prototyping (VP) is a computer aided design process concerned with the construction of digital product model (virtual prototypes) and realistic graphical simulations that addresses the broad issue of physical layout, operational concept, functional specifications and dynamic analysis under various operating environment. The VP technology has been extensively and successfully applied to the automobile and aerospace fields. An automobile can be fabricated virtually using the VP technology and allows various team members to view the 3D image of finished products, evaluate the design, and identify the production problems prior the actual start of mass production.
respectively. The spectrum of IL in Figure 1b, which was almost conform to the literature , was confirmed. That is, the presence of the O-H at 3404 cm -1 (while the band at ~ 3540 cm -1 could be due to the O-H stretching mode of intercalated water), the C-H stretching bands located at 2966 cm -1 and 2893 cm -1 , C-O vibration at 1060 cm -1 and the C-H vibration at ~1450 cm -1 , as well as the imidazolium framework vibration at 1633 cm -1 (ν(C=N)), 1573 cm -1 (ν(C=C)) and 1168 cm -1 (ν(C-N)) are primarily evidenced. In figure 1c, the bands at 1732 cm -1 is the evidence of ester group. While the absorbance bands of O-H in IL and MAA disappeared. The lost of characteristic peaks of hydroxyl groups and the present bands of ester group confirmed that the esterification reactions between the IL and the MAA had been finished and the IL-MAA SAM formed successfully. The FT-IR spectrum of IL-MAA also exhibits IL features, which are the presence of the C-H stretching bands located at about 3120 cm -1 and 2964 cm -1 , and the C-H vibration at 1455 cm -1 , as well as the imidazolium framework vibration at 1632 cm -1 and 1573 cm -1 .
15 Read more
Data analysis was performed using statistical analysis software (SPSS version 18). All data are presented as mean ± standard deviation for continuous variables, and as numbers with percentages for categorical variables. We used correlation and linear regression models for assessment of the association of LV mass index, aortic root size, age, and duration of hypertension, with MAA. We performed 1-way analysis of statistical variance with Bonferroni correction to compare the aortic root size, MAA dimension, and duration of hypertension between the 4 groups of LV geometry.
Overall, the results indicate that the envelope organization of LDV virions is markedly different from that of togavirus virions, even though superficially the morphologies of their virions are similar. In Sindbis virus, the envelope proteins form an icosahedral shell which is composed of trimers of het- erodimers of the E1 and E2 spike proteins, with molecular masses of about 50 kDa (1, 12, 22). The outer shell is stabilized by disulfide bonds within the large ectodomains of the E1 and E2 proteins, which are rich in cysteine residues (13, 22). Disruption of the bonds by incubation with 5 mM DTT results in rapid loss of infectivity, just as observed for LDV, but in contrast to LDV, loss of infectivity is associated with disassem- bly of the envelope and release of the nucleocapsid (1, 12, 13). On the other hand, LDV virions seem much more unstable than Sindbis virus virions under other conditions not involving disulfide bond reduction (4, 20). For example, during prepa- ration for electron microscopy the envelope of LDV virions tends to slough off, releasing cylindrical structures with a diameter of 8 to 14 nm (4). These structures may be composed of the VP-3–VP-2/M heterodimers. Furthermore, the envelope of LDV is removed from the nucleocapsid by treatment with Nonidet P-40 at concentrations as low as 0.01%, whereas at least 10-fold-higher Nonidet P-40 concentrations are required for removal of the envelope of Sindbis virus (4). These observations lead us to speculate that the primary function of the disulfide bonds between VP-3 and VP-2/M may be to stabilize the virus attachment site rather than to stabilize virion structure per se.
All chemicals and solvents used were of reagent grade. Solvents were dried and distilled before use according to the standard procedure. Redistilled and deionized water was used wherever it was needed. Methanol and chloroform were purchased from Merck Company. Ampicillin was purchased from Hi media (India). N-isopropylacrylamide (NIPAAm) from Across Organics (USA) re-crystallized with N-hexane at 40 o C and dried under vacuum, stored at 4 o C. N-vinyl 2-
Thus, above-mentioned changes after the incubation in BM 199 of PUU and film materials with drug on their basis allow us to conclude about the influence of the concentration of VP-VA copolymer in the structure of the polymer matrix on their physical-mechanical properties. So, at minimum content of copolymer in the structure of the PUU under the influence of BM 199 there is an increase of strength characteristics, while increasing the copolymer content causes a decrease of strength (at 60% of VP-VA) and relative elongation at break (from 40% of VP-VA). It is confirmed by the well-known data that increase in amount of a hydrophilic component leads to increase of biodegradation [4, 5]. For all film materials with D-cycloserine based on PUU with fragments of copolymer VP-VA after the incubation in BM 199 there is a decrease of tensile strength and relative elongation at break. It allows concluding that the introduction of D-cycloserine into the PUU contributes to their biodegradation, which is probably due to release of D- cycloserine from the polymer matrix. This is because D- cycloserine is water-soluble drug. Therefore its release happens due to diffusion which promotes penetration of BM 199 into a polymer matrix and its swelling. And it in turn promotes to degradation of polymer material [12, 13]. 3.2. Study of Biodegradation by ATR FT-IR Spectroscopy
in previous work .Moreover, the aggregation of Na-MMT/NIPAm-VP and Na-MMT/NIPAm- AMPS-Na nanogel composites in aqueous solution is determined from the critical aggregation concentration (cac; mol/L) as confirmed from Figure 4. Careful inspection of data indicates that the cac values were reduced for Na-MMT/NIPAm-VP nanogel in sea water more than fresh distilled water. Moreover, Na-MMT/NIPAm-AMPS-Na nanogel does not aggregated in bulk sea water solution and behaves as strong electrolyte and cannot act as amphiphilic nanoparticles in sea water . This means that Na-MMT/NIPAm-AMPS-Na will absorb water and their particle size increased due to strong hydrophilicity of SO 3 Na groups. This observation can be referred to the formation of strong
14 Read more
Cellulose nanocrystals from ramie fibers were produced and characterized according to a procedure reported previosly. 138 The size of the obtained rod-like CNCs was determined to be 3-15 nm in diameter and 50-250 nm in length. Poly(N-isopropylacrylamide) was grafted from CNCs via surface-initiated single-electron transfer living radical polymerization (SI-SET-LRP) with various reaction conditions producing a variety of graft densities and molecular weights. Of the various molecular weights of the polymer grafts obtained in the previous study, one case was examined as Pickering emulsion stabilizer on the basis of work by Saigal et al. 195 in which silica nanoparticles with the lowest graft densities of (2- (dimethylamino)ethyl methacrylate) (PDMAEMA) were shown to be the most robust and efficient emulsifiers. From the high emulsifying efficiency of low graft density nanoparticles, it was implied that they had a high-affinity adsorption isotherm at the oil-water interface, which required low particle concentrations. The CNCs utilized in this study were carrying poly(NiPAAm) grafts polymerized from CNCs containing a molar ratio between initiator [Br] and anhydroglucose units [AGU] in CNCs ([Br]:[AGU]) of 5:3 and a number average molecular weight (M n ) of 12,170 g/mol.
163 Read more
Narrow MWD homopolymers of MOSu 35 were prepared with suitable MW’s for drug conjugation by the application of Cu mediated ATRP procedures. Different MW’s were obtained by varying the ratio of monomer to initiator. At the time of writing this thesis, the polymerisation of 35 was the only example of the homopolymérisation of a (meth)acrylic acid derived active ester by ATRP procedures described in the literature. However, evidence supporting an extremely fast polymerisation and a high level of irreversible termination during initiation and the early stages of propagation was found for 35, resulting in higher than expected values for M„. It was proposed therefore that the polymerisation of 35 may also involve conventional redox-initiated free radical polymerisation kinetics in addition to the ATRP process. Homogeneous conditions for a high yielding polymerisation were found to be 43 wt% DMSO at > 80 °C. These reactions were carried out on a 1.8 to 6 g scale. Narrow MWD PMOSu 36 was also achieved in acetone and THF solutions, with the polymer precipitating during heating at lower MW’s (M„ = 1,800 to 20,000 g-mol'^) than obtained in the homogenous DMSO reactions. It was also shown that an active ester-based block copolymer, poly(MOSu-b-ethylene glycol) 56, could successfully be prepared by using a PEG macro-initiator 55 synthesised by the functionalisation of monomethoxy-PEG 53.
231 Read more