top of page

Mysite Group

Public·223 members

Brownness



As a Caribbeanist, and as another child of the Cuban diaspora in the United States who critically questions what we must not continue doing with Cubanity, I ask, Can the semiosis of US-Latinx brownness operate without Afro-Caribbean and African American thought?2 If the semiosis of brownness requires the diction and thinking of black philosophy, literature, critical theory, religion, music, and culture to operate, then what, we might ask, does it offer the semiosis and poiesis of blackness in return?




brownness



Evolutionary psychology theories propose that contact with green, natural environments may benefit physical health, but little comparable evidence exists for brown, natural environments, such as the desert. In this study, we examined the association between "brownness" and "greenness" with fasting glucose among young residents of El Paso, Texas. We defined brownness as the surface not covered by vegetation or impervious land within Euclidian buffers around participants' homes. Fasting glucose along with demographic and behavioral data were obtained from the Nurse Engagement and Wellness Study (n = 517). We found that residential proximity to brownness was not associated with fasting glucose when modeled independently. In contrast, we found that residential greenness was associated with decreased levels of fasting glucose, despite the relatively low levels of greenness within the predominantly desert environment of El Paso. A difference between the top and bottom greenness exposure quartiles within a 250 m buffer was associated with a 3.5 mg/dL decrease in fasting glucose levels (95% confidence interval: -6.2, -0.8). Our results suggest that within the understudied context of the desert, green vegetation may be health promoting to a degree that is similar to other, non-desert locations in the world that have higher baselines levels of green.


Results: At 4, 16 and 22 h following oviposition, Pp IX concentrations in LBS and DBS groups were significantly higher in shell glands than in liver (P


Conclusions: In this study, the regulatory mechanisms of eggshell brownness were studied comprehensively by different eggshell color and time following oviposition. Results show that Pp IX is synthesized de novo and stored in shell gland, and ALAS1 is a key gene regulating Pp IX synthesis in the shell gland. We found three transporters in Pp IX pathway and three metabolites in shell glands and uterine fluid that may influence eggshell browning.


This essay looks at the place of race in Creole Nationalism in Jamaica. It asserts that Creole Nationalism is also Brown Nationalism in Jamaica and that its racial ideas can be seen through the thought of Norman Manley, the father of Creole Nationalism; his wife Edna, its cultural mouthpiece; and the politics of Alexander Bustamante. The essay contends that Creole Nationalism rooted itself in notions of indigeneity and the elevation of hybridity as the basis of the state's claims to legitimacy; legitimized a racial hierarchy that centered brownness; and provided a way to think self and nation in independence through the national motto. It contends that an aspiration to brownness was embedded in the identity politics emerging therein, which served to obscure the racial order and maintain the subordinate place of blackness in postcolonial Jamaica.


Brown eggs are popular in many countries and consumers regard eggshell brownness as an important indicator of egg quality. However, the potential regulatory proteins and detailed molecular mechanisms regulating eggshell brownness have yet to be clearly defined. In the present study, we performed quantitative proteomics analysis with iTRAQ technology in the shell gland epithelium of hens laying dark and light brown eggs to investigate the candidate proteins and molecular mechanisms underlying variation in chicken eggshell brownness. The results indicated 147 differentially expressed proteins between these two groups, among which 65 and 82 proteins were significantly up-regulated in the light and dark groups, respectively. Functional analysis indicated that in the light group, the down-regulated iron-sulfur cluster assembly protein (Iba57) would decrease the synthesis of protoporphyrin IX; furthermore, the up-regulated protein solute carrier family 25 (mitochondrial carrier; adenine nucleotide translocator), member 5 (SLC25A5) and down-regulated translocator protein (TSPO) would lead to increased amounts of protoporphyrin IX transported into the mitochondria matrix to form heme with iron, which is supplied by ovotransferrin protein (TF). In other words, chickens from the light group produce less protoporphyrin IX, which is mainly used for heme synthesis. Therefore, the exported protoporphyrin IX available for eggshell deposition and brownness is reduced in the light group. The current study provides valuable information to elucidate variation of chicken eggshell brownness, and demonstrates the feasibility and sensitivity of iTRAQ-based quantitative proteomics analysis in providing useful insights into the molecular mechanisms underlying brown eggshell pigmentation.


Brown eggs dominate commercial markets in many countries, such as China, Britain, France, Italy and Portugal. Eggshell color has low genetic correlation with external and internal egg quality traits [1]. However, consumers still regard eggshell color as an important indicator of egg quality. Market tests suggest that consumers positively perceive brown eggs as being more nutritious and flavorful, and that hens laying brown eggs are thought to be organically fed [2]. Consumers who prefer brown eggs also pay attention to the intensity of eggshell brownness, and exhibit a preference for uniformity in eggshell brownness [3].


A total of 765 eggs from 281 hens were collected on three consecutive days, and eggshell color, egg shape index, eggshell strength, eggshell thickness and eggshell weight were measured. The L* value was used to represent the intensity of eggshell brownness, as verified by the high correlation coefficient between the L*value and protoporphyrin IX quantity in the eggshell [11]. Lower L* values are associated with darker eggshells, and vice-versa. The Shapiro-Wilk normality test showed that the eggshell color (L* value) of the 281 hens followed a normal distribution (W = 0.9938, p-value = 0.3077). Chickens were selected according to L* values from two tails of the selected eggs; the selected chickens consistently laid eggs with uniform eggshell brownness throughout this laying period. Although the two groups of chickens used for proteomic analysis laid eggs differing significantly in eggshell color, they did not differ in other egg parameters (egg shape index, eggshell strength, eggshell thickness and eggshell weight) (Table 1). This sample selection method was applied in order to eliminate potential interference caused by differences in the other eggshell traits.


The objective of the present study was to identify proteomic differences in the shell gland epithelium of chickens laying light and dark brown eggs in order to provide insight into the mechanisms regulating the intensity of eggshell brownness. Four different biological replicates from each group were analyzed in order to estimate the relative abundance of proteins using iTRAQ-labeling technology.


The intensity of eggshell brownness is dependent on the concentration of protoporphyrin IX in the eggshell [11], which will be affected by the total amount of protoporphyrin IX and the size of eggshell. Given the same amount of protoporphyrin IX, larger eggs will have lighter brownness than smaller eggs. To avoid this interference, we identified two groups of hens that laid eggs with different levels of eggshell brownness, but with similar egg shape index, eggshell thickness and eggshell weight. This approach ensured that the difference in brownness between two groups was caused by the total amount of protoporphyrin IX, rather than the size of eggshell.


The results showed that 2250 proteins were reliably identified in the chicken shell gland epithelium, and 147 proteins were differentially expressed between the two groups. The biosynthesis, transport, accumulation and deposition of protoporphyrin IX in the shell gland are coordinated with eggshell mineralization. At 6 h post-oviposition the next egg reaches the shell gland to undergo mineralization during nearly 19 hours; meanwhile, the protoporphyrin IX granules can be observed in the epithelium of the shell gland, suggesting that the proteins associated with protoporphyrin IX synthesis and transport are active at this time. Our previous studies indicated that the intensity of eggshell brownness was determined by the content of protoporphyrin IX deposited onto the eggshell, and that the protoporphyrin IX content in the eggshell depends on the accumulation of protoporphyrin IX in the shell gland epithelium [11]. Therefore, the differentially expressed proteins (S2 Table) that are involved in protoporphyrin IX synthesis and transport warrant further investigation. The biosynthesis pathway for protoporphyrin IX has been fully elucidated. Protoporphyrin IX is formed in the mitochondrion and the involved enzymes are mainly located in the mitochondrial inner or outer membrane, suggesting that the differentially expressed proteins located in the mitochondrial inner or outer membrane, based on their cellular component, might be active during the synthesis and transport of protoporphyrin IX. The functional and pathway analysis gave an overall view of the differentially expressed proteins (S2 Table). In addition, we searched databases and related literature for detailed functional descriptions of these differentially expressed proteins. Finally, we identified eight putative protein candidates (Table 4). These include four proteins that could function in protoporphyrin IX synthesis and transport: iron-sulfur cluster assembly protein (Iba57), ovotransferrin (TF), the 18 kDa translocator protein (TSPO) and the adenine nucleotide transporter (SLC25A5). An additional four proteins are involved in the oxidative phosphorylation pathway and could play vital roles in the production and accumulation of protoporphyrin IX in the shell gland epithelium: cytochrome c oxidase subunit (COX7A2L), NADH dehydrogenase (NDUFA5), NADH-ubiquinone oxidoreductase chain 5 (ND5) and succinate dehydrogenase. 041b061a72


About

Welcome to the group! You can connect with other members, ge...
bottom of page