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The purpose of this study is to evaluate the content of bioactive pigments in coloured callus of Azadirachta indica and to understand the correlation between the callus colours with their bioactive constituents, antioxidant properties and cytotoxicity. These assessments will yield valuable insight into the use of in vitro-derived pigments for possible use as functional natural colourants.

In this study, the authors have successfully developed a protocol to produce leaf-derived callus of various colours with enhanced content of bioactive pigments in A. indica through plant tissue culture. Comparative analysis of the pigments content (chlorophyll, carotenoid, phenolics and anthocyanins) in the coloured callus was conducted, followed by evaluation of its bioactive properties. The antioxidant properties against 2,2-diphenyl-1-picrylhydrazyl and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radicals, ferric reducing antioxidant power and cytotox activities of the coloured callus extracts were also reported.

Callus of various colours were successfully produced in A. indica through plant tissue culture, and their valuable pigment content and bioactivity were evaluated. The green callus contained the highest amount of anthocyanin, followed by brown and cream callus. The total anthocyanin contents in both the green and brown callus was more than two-fold higher than that in cream callus. Contrasting observation was obtained for total phenolic content (TPC), where the TPC of cream callus was significantly higher than that in brown callus. Nevertheless, the green callus also exhibited the highest TPC. Green callus also contained the highest amount of total chlorophyll and carotenoid, as well as exhibited the highest antioxidant potential, and was found to be the only extract with active cytotox activity against SKOV-3 cells. Correlation analysis revealed that the excellent bioactivity exhibited by the coloured extracts was strongly correlated with the bioactive pigments present in the callus.

The major bioactive compounds identified in the methanolic extracts of A. indica coloured callus are anthocyanins, phenolics, chlorophylls and carotenoids. Future research work should include improvements in the extraction and identification methods, which may lead to detection and determination of other compounds that could attribute to its bioactivity, to complement the findings of the current study.

This analysis provides valuable information on the application of plant tissue culture as an alternative source for sustainable production of major pigments with medicinal benefits in A. indica for possible use as functional natural colourants.

A comparative study on bioactive pigment production in coloured callus from A. indica leaves and its antioxidant potential and cytotoxicity is original. To the best of the authors’ knowledge, this is the first report detailing a comparative evaluation on the production of coloured callus in A. indica and its relative biochemical composition and bioactive properties.

The purpose of the present study is to understand the role of auxin and cytokinin in stimulating the production of pigmented callus in Orthosiphon stamineus and to gain correlation between the callus colours with their antioxidant capacity and bioactive constituents.

In this study, plant tissue culture was used to induce production of callus of various colours from leaf explants of O. stamineus, via manipulation of plant hormones (0-2.0 mg L⁻¹ indole-3-acetic acid [IAA] and Kinetin [Kin]). The coloured callus was subjected to solvent extraction and used for quantification of its carotenoid, chlorophyll, anthocyanin and phenolic contents. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity of the extracts was also evaluated, before and after four weeks of storage at −20°C.

The highest mean (per cent) explants that produced roots (93.33 ± 0.05 per cent) were observed when the cultures were supplemented with 2.0 mg L⁻¹ IAA. The colour of the callus changed with time, from green to cream to brown after two and four months of culture, respectively. Optimum production of green callus was achieved with addition of 2.0 mg L⁻¹ Kin plus 1.0-2.0 mg L⁻¹ IAA to the media, while cream callus in 0.5 mg L⁻¹ Kin plus 2.0 mg L⁻¹ IAA and brown callus in 0.5 mg L⁻¹ Kin plus 1.5 mg L⁻¹ IAA. Green callus was found to contain the highest amount of chlorophylls, carotenoid and anthocyanin, while cream callus contained the highest amount of phenolic compounds. The amount of pigments and secondary metabolites in the callus extracts decreased after four weeks of storage, except anthocyanin. The antioxidant potential of the extracts also increased after storage.

The major compounds identified in the methanolic extracts of O. stamineus-coloured callus are chlorophylls, carotenoids, flavonoids and phenolic acids. Future research work should include improvements in the extraction and identification methods which may lead to detection of other compounds that could attribute to the antioxidant capacity, to complement the findings of the current study.

This analysis provides valuable information on the application of IAA and Kinetin (Kin) to manipulate the content of major pigments with medicinal benefits in O. stamineus by using the plant tissue culture system.

A comparative study on antioxidant capacity and bioactive constituents of pigmented callus from O. stamineus leaves is original. To the best of the authors’ knowledge, this is the first attempt of comparative evaluation on antioxidant potential of O. stamineus-coloured callus produced using IAA and Kin.

This study aims to determine the appropriate irradiation dose for induction of somaclonal variation in mass of unorganized parenchyma cells derived from sainfoin (Onobrychis viciifolia) tissues.

To investigate the feasibility of UV-B irradiation (312 nm), seeds and callus of sainfoin were exposed to five different intensities (20-100 per cent) for evaluating the effectiveness of phytochemical constituents and cellular behaviour.

Although percentage of seed viability reduced in 20 per cent intensity of UV-B irradiation compared with control seeds, the germination speed significantly enhanced from 3.58 to 5.42. The spectrophotometer analysis confirmed that concentrations of chlorophyll (a and b) decreased after UV-B exposure as compared with control callus. Also, carotenoid content showed significant differences among treated calli. Flavonoid and phenolic contents were observed to gradually increase when the non-irradiated callus subjected to 40 and 60 per cent intensities of UV-B irradiation, respectively. Observation on cellular behaviour such as determination of nuclear and cell areas, mitotic index and chromosomal aberrations were also detected to change in different intensities of UV-B irradiation. Fragmented and aneuploidy aberrations were only observed in exposed cells with more than 40 per cent intensity of UV-B irradiation.

In reality, radiocytological evaluation was proven to be essential in deducing the effectiveness of UV-B irradiation to induce somaclonal variation in callus tissue of sainfoin.

To gain a better understanding of the impact of students’ home languages and cultural experiences on reading and writing instruction, the instructional methods and materials that best supported these students’ emerging bilingualism, and the contributions of their families in their utilization of their home languages and cultural experiences in a school setting. Mixed methods provided data on the literacy development in both home and school languages of three first-grade Latino students who were non-native English speakers enrolled in a school literacy intervention program for 12 to 20 weeks. The students’ confidence and motivation within their reading and writing instruction improved greatly with the encouragement of the use of their home languages and cultural experiences. All three students showed gains in speaking, reading, and writing in both their home and school languages. They made solid and useful connections between the languages and the texts, and drew upon their cultural experiences, which strengthened their reading and writing strategies in both languages. Involving the children’s families in lessons and in activities at school, and supporting their use of reading and writing at home, helped build relationships among the participants, families, and school faculty. This contributed to the beginnings of new understandings on the part of the school’s teachers and administration. Students need to have the space to use their home languages and cultural experiences in school, and I describe how educators in varied educational settings can replicate the same kinds of methods, materials, and support I offered to these students. I also describe suggested ways that teachers and administrators could include the knowledge of emergent bilingual families within the life of the school to further expand all students’ learning and promote social justice in the classroom setting.

This paper aims to empirically analyze the extent to which advertising reception among consumers with a migration background (German-Turks) is influenced by a person’s strength of national identifications with his/her country-of-origin (COO) and with his/her country-of-residence (COR). The focus is on Turkey-sensitive advertisements (ads) of telecommunication service suppliers in Germany because such communication measures are quite common and about three million German-Turks constitute an economically important group.

Measures of COO and COR identification as well as of three ad reception criteria were obtained in a survey of 291 German-Turks and analyzed via moderated regression models.

Strength of COO identification was a significantly positive predictor of the frequency with which participants remembered Turkey-sensitive ads for telecommunication services. Additionally, COO identification related significantly to two criteria that capture facets of attitudes toward such ads. By contrast, COR identification acted partly as a moderator which attenuated links between respondents’ COO identification and two ad reception measures. Nevertheless, German-Turks with a strong COR identification (i.e. “accultured” consumers) were still receptive to Turkey-sensitive telecommunication services ads even if their self-image was simultaneously strongly dependent on their COO. “Alienated” German-Turks who identify neither with their COO nor with their COR were least responsive to ethnic ads.

The research indicates that marketing practitioners should not use uniform communication measures to address migrant consumers with a specific COO but segment this target group further by simultaneously considering their members’ COO and COR identifications.

The contribution of this paper results from the simultaneous inclusion of both COO and COR identifications as factors explaining differences in reactions to communication measures among migrant consumers which share the same COO. Furthermore, the scarcity of empirical work on reactions of German-Turks to ethnomarketing is reduced.

Advanced ceramics such as alumina are widely in use in the design of components for high engineering applications mainly because of their high wear resistance, high compressive strength, low specific density and high temperature capability. Processing and manufacturing of pure alumina products is a difficult and expensive task. Therefore, additional compounds are added to alumina to achieve a more complex component design and to minimise the product processing and manufacturing costs. This paper examines the effects of speed, load values and the addition of Cr₂O₃, SiO₂ and MnO₂ compounds on the friction and wear behaviour of alumina ceramic. Wear tests for alumina and alumina samples containing w1.5% Cr₂O₃ w3% SiO₂ and w1.5% MnO₂ compounds was carried out on a pin‐on‐disc machine. Tribological tests were under 2.5, 5 and 10N loads and at 0.5, 0.75 and 1m/Sec speeds. The specific wear rates were deduced from mass loss. The wear rate for alumina without additional compounds was in the order of 10^–8 to 10^–7mm²/N, while the wear rate values for alumina with additional compounds were in the order of 10^–6. Moreover, the wear rate showed more sensitivity to the applied load, particularly at low sliding speeds. Furthermore, it is concluded that a 20 per cent decrease in the sintering temperature resulted in 300 per cent increase in the specific wear rate of alumina ceramic material.

Electric fields (EFs) are known to influence cell and tissue activity. This influence can be due to thermal or non-thermal effects. While the non-thermal effects are still matter of discussion, thermal effects might be detrimental for cell and tissue viability due to thermal damage, this fact being exploited by applications like hyperthermia and tissue ablation. The paper aims to discuss these issues.

In this work the authors investigate the influence of thermal damage in the consolidation of bone formation during electrostimulation (ES). The authors introduce a mathematical model describing the migration of osteoprogenitor cells, the thermal variation, the thermal damage accumulation and the formation of new bone matrix in an injury (fracture) site.

Numerical results are in agreement with experimental data and show that EFs more intense than 7.5 V/cm are detrimental for the viability of osteoprogenitor cells and the formation of new bone.

The model is suitable to conduct dosimetry studies in support of other different ES techniques aimed at improving bone and soft tissues repair.

The policing of Black male bodies is not uncommon to America. Less known is Black male bodies policed in public libraries. Having worked at the Nashville Public Library’s Hadley Park branch, I saw behaviors and stereotypes played out on both sides of the public service desk. Hyper masculine behavior, homophobia, mental illness, and staff safety were issues that had to be faced by me and my staff. The quandary was my being a Black man who understood the ramifications of a police call or verbal exchange. Putting a Black man in a “problem” branch in a Black neighborhood was not by accident. Administrative choices were based upon racist and sexist tropes that Black men are familiar with dysfunctional environments of drugs and prostitution and don’t need a sense of safety like any other human beings.

This research explores the experiences of self-identified queer victims of intimate partner violence, their personal encounters with violence-response organizations, and the extent to which their gender/sexual identity impacted their willingness to disclose their abuse.

Eleven respondents were recruited from online queer social networking sites and were interviewed via e-mail or Skype.

All respondents identified as gender variant or had an abusive partner who identified as gender variant. All study participants reported having experienced physical abuse. Several reported sexual and emotional abuse. Respondents reported a reluctance to seek institutional support and intervention. Several respondents were unable to recognize abuse as abuse until much later. When asked about whether or not they sought intervention, most respondents in this study described a sort of isolation, where they perceived that they were facing prejudice and stigmatization, and risked being dismissed and delegitimized. Several respondents sensed that there simply were no organizations that were sensitized and available to queer-identified victims. Even if they had pursued help from existing institutions, several respondents communicated a doubt that they could truly be of service, since these institutions likely operated with heteronormative narratives and practices. Collectively, the respondents in this study describe experiences as victims of IPV that are clearly mediated by homophobia and cissism.

We emphasize the need for an “intersectional awareness” in scholarship and organizing surrounding IPV. We critique the state’s gender-based practices of violence intervention and propose alternative possibilities for more inclusive intervention and organizing on behalf of queer victims of violence.

The body of literature that exists on IPV among LGBTQ persons is small, and much of this literature is focused on how patterns of IPV differ from heterosexual violence. In exploring IPV among self-identified queer victims, we depart from most research on IPV in that our analysis is not so much concerned with the gender or sex assignment of the victim, but rather the gendered context in which the violence is playing out.

This letter to David R. Maines celebrates our friendship over the last 35 years. I read his voice in emails, handwritten letters, and recollected phone conversations to display the meaningful exchanges of our scholarly friendship. I thank Dave for teaching me how to retire from the academy and grow older with purpose and grace. Highlighting his expert mentoring of my book Friendship Matters (1992), I recall how his suggested revisions for the chapters on aging anticipated a poignant array of our own experiences as friends in our later years. Finally, I appreciate his cultivated interests in drawing, writing poetry, and playing guitar, and thank him for encouraging my music. I am grateful for his dedication to esthetic endeavors, which warmly shaped our friendship during our later years.