Black Background Research Articles

Feasibility Study For Large Scale Thermal Convective Flow Measurements In Building Physics

The Department of Building Physics / Energy-efficient Buildings at the Rheinland-Pfälzische Technische Universität Kaiserslautern-Landau is about to put a novel research-building into commission, the “Small House III”. Among other measurement equipment, a system for volumetric, large-scale, high-resolution flow velocity measurement should be utilized. In this paper, requirements for such a system are detailed, a suitable measurement system is proposed and a feasibility study for the verification of the system requirements is conducted. To this end, a tailored system for large-scale Lagrangian particle tracking (“Shake-the-Box”) is applied to thermal convective flow measurements above an electric radiator close to a wall. As a result, it is found that the designed volumetric velocity measurement system is capable of successfully operating in the design environment without minimal disturbance of the low-speed convection flow. . After a relatively short setup time (about 5 hours, including camera setup, calibration and self-calibration) up to 10000 images at 50 Hz (200 seconds) have been recorded continuously. Shake-the-Box results show a decline of the number of tracked particles from initially 48000 to about 8000 (with a half-life span of about 100 seconds for the helium filled soap bubbles used for seeding). Applying fine scale reconstruction (data assimilation), a vector spacing of 4 mm could be achieved for instantaneous volumetric velocity snapshots. Averaging resulted in a 2 mm vector spacing with an average of 3300 particles per bin and 410 particles per bin for 1 mm vector spacing (with 75% bin overlap). Weaker particles could only be detected in front of a black background. Using a white background (default background for later applications), weak particles could not be detected as well, so the number of detected particles and the measurement volume decreased slightly compared to the black background. Overall, the feasibility study successfully confirmed the readiness of the measurement system for the intended use for “Small House III” measurements.

Black hole bulk-cone singularities

Lorentzian correlators of local operators exhibit surprising singularities in theories with gravity duals. These are associated with null geodesics in an emergent bulk geometry. We analyze singularities of the thermal response function dual to propagation of waves on the AdS Schwarzschild black hole background. We derive the analytic form of the leading singularity dual to a bulk geodesic that winds around the black hole. Remarkably, it exhibits a boundary group velocity larger than the speed of light, whose dual is the angular velocity of null geodesics at the photon sphere. The strength of the singularity is controlled by the classical Lyapunov exponent associated with the instability of nearly bound photon orbits. In this sense, the bulk-cone singularity can be identified as the universal feature that encodes the ubiquitous black hole photon sphere in a dual holographic CFT. To perform the computation analytically, we express the two-point correlator as an infinite sum over Regge poles, and then evaluate this sum using WKB methods. We also compute the smeared correlator numerically, which in particular allows us to check and support our analytic predictions. We comment on the resolution of black hole bulk-cone singularities by stringy and gravitational effects into black hole bulk-cone “bumps”. We conclude that these bumps are robust, and could serve as a target for simulations of black hole-like geometries in table-top experiments.

Cultural differences and migrants’ interpretations of their voices

Purpose The purpose of this survivor-researcher-led study is to explore the agency of voice-hearers who are migrants and/or from black and minority ethnic backgrounds in actively negotiating the gaps between their understanding of hearing voices, and those of their family, their society or the medical establishment. Design/methodology/approach This study draws four case studies of voice-hearers, who are migrants and/or from black and minority ethnic backgrounds. Data were thematically analysed. Findings This study shows how bilingual voice-hearers related emotionally to voices in one or two languages. Originality/value This study is original in that it shows that bilingual voice-hearers may hear their voice/s in either their native language or second language, but that in both cases voices may embody strong positive or negative emotions.

The impact of using reverse polarity text for children with vision impairment assessed using light-adapted flicker electroretinogram

ABSTRACT Clinical Relevance Children with vision impairment can have difficulty accessing classroom reading material and knowledge of which students are likely to have improved performance reading performance with reverse polarity would be of value to educators. Background Printed material is typically presented as black text on a white background; however, reversing the polarity to white text on a black background may improve the reading speed for children with vision impairment. This study sought to identify the visual function or pathological features of children with vision impairment where reversing the polarity of text would improve their reading performance. Methods Forty-eight vision-impaired participants (27 male), aged 5–18 years with binocular visual acuities between 0.18–1.52 logMAR, were included. Reading performance was assessed by changes in Critical Print Size (ΔCPS), Maximum Reading Speed (ΔMRS) in normal and reverse polarity digital print, and numeric reading speed (ΔNRS) with normal and reverse polarity fonts. Correlations were made with 30 Hz flicker electroretinogram amplitude and high/low contrast acuity. Paired nonparametric tests evaluated significance in pathological condition groups. Results Significant negative correlations were only found between the 30 Hz flicker amplitude and ΔMRS (r = −.42, p = .028) and ΔNRS (r = −.46, p = .027). Follow-up pairwise comparisons based on pathology group only showed a significant effect of the retinal dystrophy group and CPS (n = 12, z = −2.24, p = .025). All other pairwise comparisons based on group were non-significant (p > .05). Conclusions This study did not identify a specific pathological group or visual functional measure that could be used as a clinical marker to predict the impact of reversing polarity. However, significant improvements could be made in reading performance for some children and so a reading performance assessment is recommended for all children with vision impairment.

Experiences of Self-Sampling and Future Screening Preferences in Non-Attenders Who Returned an HPV Vaginal Self-Sample in the YouScreen Study: Findings From a Cross-Sectional Questionnaire.

We assessed experiences of human papillomavirus (HPV) vaginal self-sampling and future screening preferences in an ethnically and socio-economically diverse group of women overdue for cervical screening. A postal questionnaire was embedded in the YouScreen self-sampling trial in England: 32.5% (2712/8338) of kit completers returned the survey. Kit non-completers were encouraged to return a questionnaire, but no responses were received. Participants were ethnically diverse (40.3% came from ethnic minority backgrounds), and 59.1% came from the two most deprived quintiles. Differences in confidence in kit completion, trust in the test results and intention to attend a follow-up test if HPV-positive were evaluated using Pearson's χ2 analyses. Binary logistic regression models explored predictors of a future screening choice and preferences for urine versus vaginal self-sampling. Most kit-completers reported high confidence in self-sampling (82.6%) and high trust in the results (79.9%), but experiences varied by ethnicity and screening status. Most free-text comments were positive but some reported difficulties using the device, pain or discomfort. Most women would opt for self-sampling in the future (71.3% vs. 10.4% for a clinician-taken test) and it was more often preferred by ethnic minority groups, overdue screeners and never attenders. Urine self-tests were preferred to vaginal tests (41.9% vs. 15.4%), especially among women from Asian, Black or Other Ethnic backgrounds. Kit-completers were confident, found the test easy to complete, and trusted the self-sample results. However, experiences varied by ethnic group and some women highlighted difficulties with the kit. Most women would prefer self-sampling in the future, but it was not a universal preference, so offering a choice will be important. We did not have direct patient and public involvement and engagement (PPIE) in the questionnaire design. However, patients and public representatives did input into the design of the YouScreen trial and reviewed the wider study materials (e.g. participant information sheet). This questionnaire study was embedded in the YouScreen trial. The protocol for the YouScreen trial is available at https://www.isrctn.com/ISRCTN12759467. The National Institute for Health Research 43 Clinical Research Network (NIHR CRN) Central Portfolio Management System (CPMS) ID is 4441934.

Determination of the Color Change of Various Esthetic Monolithic Monochromatic Computer-Aided Design/Computer-Aided Manufacturing Materials.

Dental technology has developed materials for prosthetics that are very similar to natural teeth and offer a good balance between durability and esthetics; however, some of these materials are not very color-stable under the influence of external factors. Therefore, the aim of this study is to determine and compare the color change (∆E00) of different esthetic monolithic monochromatic CAD/CAM materials after they have been thermocycled and treated with staining solutions. The color parameters were determined using a spectrophotometer on a white and black background. Five CAD/CAM materials were used for this study-CAD/CAM nanoceramic (GC Cerasmart270), CAD/CAM lithium disilicate ceramic (IPS e.max CAD), CAD/CAM polymer (Telio CAD), CAD/CAM composite (Tetric CAD) and CAD/CAM polymer-infiltrated ceramic (Vita Enamic). The test specimens produced were divided into groups and were thermocycled in distilled water. They were then stored for four weeks at 37 °C in either distilled water as a control liquid, black tea, instant coffee or red wine. The aim is also to evaluate the color changes as a function of the exposure time of the staining solutions. The results obtained were analyzed statistically. All CAD/CAM materials tend to discolor to varying degrees. Among the factors contributing to discoloration, red wine proved to be the most significant influencing factor. The conclusion from the results is that the color change is influenced by the type of material, the staining solution, the sample thickness, the color background and the aging time.

Influence of donor age, sex and ethnicity on high-titre anti-A and -B: Review of 6 million donations from two national blood providers.

Some blood operators routinely screen blood donations for high-titre (HT) anti-A/B to reduce the risk of a haemolytic transfusion reaction due to out-of-group plasma-rich components. We assessed donor factors associated with an increased likelihood of screening positive and compared routine data between England and Australia. Data were assessed from HT screening during 2018-2020 in Australia and 2018-2021 in England, totalling nearly 6 million blood donations. Screening was performed using a Beckman Coulter PK7300 analyser with a micro-titre plate saline direct agglutination test in both countries, although different reagent red cells were chosen. HT-positive was defined as testing positive at a titre of 128 or above. The likelihood of a donor testing HT-positive was greater for females than males, declined with age and was dependent on the ABO group. However, the proportion of donors testing HT-positive was consistently higher in Australia than in England: overall, 14% of group O donations and 5% of group A donations in England tested HT-positive, compared with 51% and 22%, respectively in Australia. English data also showed that donors from Black, Asian or mixed ethnic backgrounds were more likely to test HT-positive than White donors. These data demonstrate that donor sex, age, ABO group and ethnicity affect the likelihood of testing HT-positive. Differences in testing methods likely had a significant impact on the proportion of donors testing as HT-positive or -negative rather than any differences in donor populations.

Phase transition to RS: cool, not supercool

Motivated by the warped conifold compactification, we model the infrared (IR) dynamics of confining gauge theories in a Randall-Sundrum (RS)-like setup by modifying the stabilizing Goldberger-Wise (GW) potential so that it becomes large (in magnitude) in the IR and back-reacts on the geometry. We study the high-temperature phase by considering a black brane background in which we calculate the entropy and free energy of the strongly back-reacted solution. As with Buchel’s result for the conifold [1], we find a minimum temperature beyond which the black brane phase is thermodynamically unstable. In the context of a phase transition to the confining background, our results suggest that the amount of supercooling that the metastable black brane phase undergoes can be limited. It also suggests the first-order phase transition (and the associated gravitational waves from bubble collision) is not universal. Our results therefore have important phenomenological implications for early universe model building in these scenarios.

Effects of background color on survival, growth, and shell coloration of juvenile Chinese mitten crab (Eriocheir sinensis)

Background color is a crucial factor influencing the growth performance and feed utilization in crustaceans. However, little is known about its impacts on the culture performance of Chinese mitten crab (Eriocheir sinensis). In this study, we examined the impacts of six different background colors (white-W, black-BK, green-G, red-R, yellow-Y, and blue-BL) on growth, inter-molt period, and coloration and total carotenoids content of carapace of juvenile E. sinensis. The culture experiment comprised two trials: a 68-day individual culture, and a 30-day group culture. Individual culture results: No significant effects of background color were found on weight gain rate (WGR), specific growth rate (SGR), molting interval, carapace length and width, and survival rate (SR) of the juvenile crabs (P > 0.05). However, during the second molting cycle, the BL group exhibited the highest WGR, and the G group showed the lowest hepatopancreas index (HSI). Meanwhile, markedly lower feed conversion ratio (FCR) was obtained for the W group compared to the G and BK groups. Group culture results: Significantly higher SR was recorded for the BK group, and the highest limb loss rate was detected for Y group indicating the significant effects of background color on survival and aggressiveness of juvenile E. sinensis. Moreover, background color impacted the carapace coloration indices where the W, BK and Y groups showed the highest brightness (L*), redness (a*), and yellowness (b*) values, respectively. Furthermore, correlation analysis revealed a positive linear relationship between the L* value and background color (y =0.1638x+27.961, R2=0.613). In conclusion, our results demonstrated that background color significantly affects culture performance and carapace color. Black background color was shown to enhance the survival rate and reduce the limb amputation rate under group culture condition. These results provide new insights on the optimization of farming technology for juvenile E. sinensis.

Predicting Survival in Mucinous Adenocarcinoma of the Appendix: Demographics, Disease Presentation, and Treatment Methodology

BackgroundMucinous adenocarcinoma of the appendix (MACA) follows a complex disease course with variable survival. Large-scale predictive modeling may determine subtle yet important prognostic factors otherwise unseen in smaller cohort analyses.MethodsPatients with MACA were identified from the Surveillance, Epidemiology, and End Results (SEER) Research Plus database (2005–2019). Primary, secondary, and tertiary outcomes were disease-specific survival (DSS), overall survival (OS), and average annual percent change (AAPC) in incidence.ResultsAmong 4,258 included patients, MACA was most frequently diagnosed at 50 to 69 years (52.0%), with female preponderance (55.9%). MACA incidence AAPC was 3.8 (95% confidence interval [CI] 1.9–5.9). For patients with exclusive, first-diagnosis MACA included in survival analysis (3,222 patients), median DSS and OS were 118 and 88 months, respectively. In DSS-based multivariable analysis, worse prognosis was associated with non-Hispanic Black background (HR 1.36, 95% CI 1.02–1.82; p = 0.036), high grade (grade 3 HR 3.10, 95% CI 2.44–3.92; p < 0.001), lymphatic spread (HR 2.73, 95% CI 2.26–3.30; p < 0.001), and distant metastasis (HR 5.84, 95% CI 3.86–8.83; p < 0.001). In subcohort analysis of patients with rationale for cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC, 2,387 patients), CRS-HIPEC was associated with survival benefit compared with surgery alone but only for moderate-grade tumors (median DSS/OS 138/138 vs. 116/87 months; p < 0.001).ConclusionsMucinous adenocarcinoma of the appendix incidence is increasing in the United States. Survival rates are affected by both demographics and classical risk factors, and CRS-HIPEC-associated survival benefit predominantly occurs in moderate-grade tumors. Further exploration of biologic and clinicopathologic features may enhance risk stratification for this disease.

Effect of thickness on the translucency of machinable and printable ceramic-glass polymer materials

ObjectivesTo assess the translucency of machinable and printable ceramic-glass polymer materials with different thicknesses. MethodsFive ceramic-glass polymer materials were tested: one 3D-printable material, Permanent Crown resin (3D), two machinable materials available at low translucency (LT) and high translucency (HT) levels, VITA Enamic (VE) HT/LT, and Cerasmart 270 (CS) HT/LT. A total of 100 specimens were produced across 10 subgroups (n = 10) with thicknesses of 1 mm and 1.5 mm. The colour coordinates of the specimens were measured against black and white backgrounds using a spectrophotometer. Translucency was quantified using the Relative Translucency Parameter (RTP), calculated via the CIEDE2000 formula. A two-way ANOVA followed by post-hoc tests with Bonferroni correction (α = 0.05) was used for statistical analysis. ResultsThe RTP for both thicknesses were ranked as follows: CSHT > VEHT > CSLT > 3D > VELT. The RTP of the 3D was lower than that of the HT machinable materials (CSHT and VEHT) for both thicknesses (p < 0.05). No significant difference was observed between the RTP of 3D and CSLT at 1.5 mm (p = 1.000); however, at 1 mm, the RTP of the 3D was lower than that of the CSLT (p < 0.05). Notably, the 3D showed the least translucency difference with a 0.5 mm increase in thickness. ConclusionsPrintable ceramic-glass polymer materials demonstrated lower translucency than HT machinable ceramic-glass polymer materials. Both the thickness and type significantly influenced the translucency of the LT machinable counterparts compared to the printable ceramic-glass polymer material. Clinical significancePrintable ceramic-glass polymer resins may be a suitable option for minimally invasive procedures, especially when attempting to mask undesirable-coloured abutments. When selecting HT machinable ceramic-glass polymers, clinicians should pay greater attention to the abutment colour and thickness of the restorative material.

Potential toxic elements (PTEs) in rhizosphere soils and crops under a black shale high geological background: Pollution characteristics, distribution and risk assessment

The LouShao Basin in Hunan Province is covered with two sets of black rock series containing various potential toxic heavy metal elements. The rock series are rich in various potential toxic heavy metal elements, and the weathered black shale is the main formation of local farmland soil, making it a typical area with high geological background in China. The purpose of this study is to assess the regional ecological and health risks by studying the correlation between the content of heavy metal elements enriched in rhizosphere soil, non-rhizosphere soil, and crops, and the concentration of heavy metal elements in the main source, black shale rocks. The results show that the elements in the black shale far exceed the world average of rock, severely affecting soil element concentrations. Se element is the most severely polluted in rhizosphere soil, exceeding the background value by 7 times. The concentration of heavy metals between rock-non-rhizosphere soil-rhizosphere soil-crops decreases linearly. The distribution of pollution has strong spatial autocorrelation, and the high geological background is the main reason. Pollution index results show significant pollution of Se, Cr, Hg, and Cd in crops, with the pollution of heavy metal element Cr in corn being extremely serious with Igeo = 6.71. The ecological risk order is Se > Cd > Cr > As > Pb > Hg. Humans mainly contact elements through skin contact and food chain intake. The HI value of heavy metal element Cd is greater than 1, indicating a high carcinogenic risk. Human exposure to Cd through skin contact and food chain intake may lead to related diseases such as kidney stones, and pose greater harm to children.

Breaking the concrete ceiling: Resources and strategies for career success amongst Black and Asian minority ethnic women leaders

AbstractDespite ongoing research efforts to resolve the pertinent issues with the underrepresentation of women from Black and Asian Minority Ethnic backgrounds in senior leadership positions, the problem persists. We suggest that one reason for the lack of progress is that management research has predominantly focused on the manifestation of race and gender inequality, the barriers experienced by these women, and the resulting adverse outcomes, with inadequate attention given to practical interventions for resolving these issues. We argue that an urgent and critical paradigm shift from problems to solutions is required in order to advance the field. Using the conservation of resource theory as a lens, we explore the lived experiences of 50 highly successful Black and Asian women and how they navigated the organizational labyrinth to achieve success in their careers. Our findings revealed that despite discriminatory experiences that threatened their career advancement, there were several personal and contextual resources which they drew upon to achieve career success. We develop a resource taxonomy framework illustrating these salient career advancement resources across their career journey, alongside strategies they used to protect these valuable resources. Our findings have theoretical and practical implications for career, leadership and diversity scholars and practitioners.

Charge superradiance on charged BTZ black holes

We study superradiant scattering for a charged scalar field subject to Robin (mixed) boundary conditions on a charged BTZ black hole background. Scalar field modes having a real frequency do not exhibit superradiant scattering, independent of the boundary conditions applied. For scalar field modes with a complex frequency, no superradiant scattering occurs if the black hole is static. After exploring some regions of the parameter space, we provide evidence for the existence of superradiantly scattered modes with complex frequencies for a charged and rotating BTZ black hole. Most of the superradiantly scattered modes we find satisfy Robin (mixed) boundary conditions, but there are also superradiantly scattered modes with complex frequencies satisfying Dirichlet and Neumann boundary conditions. We explore the effect of the black hole and scalar field charge on the outgoing energy flux of these superradiantly scattered modes, and also investigate their stability.

Molecular characterization, spatiotemporal expression, and background adaptation regulation of tyrosinase in loach (Misgurnus anguillicaudatus).

The Poyang Lake region is home to large-blackspot loaches (LBL), small-blackspot loaches (SBL), and non-blackspot loaches (NBL), Misgurnus anguillicaudatus. To investigate the impact of tyrosinase on spot development, the complementary DNAs (cDNA) of tyrosinase in M. anguillicaudatus (designated as Matyr) were cloned using the rapid amplification of cDNA ends (RACE)-PCR method. The full-length cDNA for Matyr was 2020 bp, and the open-reading frame comprised 1617 bp, encoding a predicted protein with 538 amino acids. Phylogenetic studies revealed that MaTyr was first grouped with Tyr of Triplophysa tibetana and Leptobotia taeniops, and then Tyr of other cyprinid fish. The quantitative reverse-transcription-PCR results show that Matyr was highly expressed in the muscle, caudal fin, and dorsal skin. The Matyr gene's messenger RNA expression pattern steadily increased from the fertilized ovum period to the somitogenesis period, and from the muscle effect stage to 6 days after fertilization, it considerably increased (p < 0.01). The Matyr hybridization signals with similar location could be found in all developmental stages of three kinds of loaches using whole-mount in situ hybridization (WISH) technology and were the strongest during the organ development period and melanin formation period. Dot hybridization signals in LBLs rapidly spread to the back of the body beginning at the period when the eyes first formed melanin, and their dimensions were larger than those of NBLs during the same time period. The body color of loaches could change reversibly with black/white background adaptation. The α-msh, mitfa, and tyr are mainly expressed in loaches adapted with a black background. Tyr gene could be involved in the development of blackspots and body color polymorphism, and contribute to organ development in the loach.

A qualitative study exploring experiences of racial minority stress in pharmacy education and practice

BackgroundDespite 49.1% of registered pharmacists in the UK being from a Black, Asian and Minority Ethnic (BAME) background, senior management roles within pharmacy are dominated by white males. People from BAME communities may experience minority stress which contributes to a professional attainment gap compared with non-BAME colleagues. Minority stress describes additional stressors, such as unconscious bias, micro-aggression and racial minority stress, experienced by minoritized people to adhere to the social norms of the majority. There is little evidence describing experiences of minority stress in pharmacy practice and education. The aim was to explore experiences of racial minority stress in pharmacy education and practice. MethodsA convenience sample of pharmacy students and pharmacists were recruited via email and social media posts to volunteer to take part in interviews and focus groups. A topic guide was used to explore experiences of unconscious bias, microaggressions and racial minority stress in education and practice. Interviews and focus groups were transcribed verbatim and inductively analysed using thematic analysis underpinned by a phenomenological approach. Ethical approval was granted from Newcastle University (5340/2020, 2430/2593). ResultsForty-five participants were recruited. Six focus groups and sixteen one-to-one semi-structured interviews were conducted. The sample was varied, with 56% (n = 25) students and 33% (n = 15) registered pharmacists from community, hospital, primary care, academia and an additional 11% (n = 5) still in foundation training in these sectors. The sample include diversity of racial identities, including 40% (n = 18) South Asian, 27% (n = 12) White, 15% (n = 7) Black, 7% (n = 3) Chinese and Arab mixed, 2% (n = 1) and 2% (n = 1) Not disclosed. Three themes were identified – Theme 1) Experiences of racial minority stress, Theme 2) Making sense of racial minority stress, and Theme 3) Responding to racial minority stress. Participants characteristics (for example skin colour, dialect, religious dress) made them feel susceptible to judgement, racist comments and microaggressions in education and practice. Participants required time to interpret, understand and make sense of incidents of racial minority stress. Responses to stressors included ‘ignoring ignorance’ and using a ‘professional identity’ to mask feelings. However, malicious comments and actions from other pharmacy staff were responded to differently to experiences from patients. Participants reported poor self-confidence to challenge racist behaviours in the workplace. ConclusionsThe aim of this study was to explore experiences of racial minority stress in pharmacy education and practice. This study shows dealing with microaggression, racial minority stress and judgement in pharmacy education and practice is a burden experienced by people from BAME backgrounds. These experiences could contribute to the professional attainment gap in pharmacy, as making sense of these experiences is an additional burden pharmacists and trainees must bear in comparison to people from non-BAME backgrounds. Further work is needed to explore interventions to reduce minority stress in pharmacy practice and education to reduce the attainment gap across the sector.

Racial differences in genomic profiles and targeted treatment use in ER+ HER2- metastatic breast cancer.

1017 Background: Despite well-documented disparities in survival between patients (pts) with Black and White racial backgrounds, there are limited data on racial equity of targeted treatment use for pts with estrogen receptor positive, HER2 negative (ER+/HER2-) metastatic breast cancer (MBC). We evaluated differences in circulating tumor DNA (ctDNA) genomic alterations in Black and White pts with ER+/HER2- MBC. Methods: This retrospective cohort study analyzed a database of 1327 pts with MBC who were treated at Washington University in St. Louis, Massachusetts General Hospital, and Northwestern University and had ctDNA testing through the commercially available Guardant360 assay. Progesterone receptor (PR) status of the ER+/HER2- pts was identified to categorize pts as ER+/PR+/HER2- (N=60 Black, N=435 White) and ER+/PR-/HER2- (N=24 Black, N=237 White). Pts were evaluated by self-reported race and use of PIK3CA, CDK4/6, and mTOR inhibitors, either through clinical trial enrollment or after FDA approval. A multivariate logistic analysis was performed to determine genomic and prognostic differences by race. Overall survival (OS) from time of first ctDNA testing was determined by subgroup. Results: Black pts with PIK3CA single nucleotide variants (SNVs) were significantly less likely to receive targeted therapy than White pts (5.9%, 1/17 pts vs. 28.8%, 45/156 pts, Fisher’s exact test p=0.045), while there was no difference in use of CDK4/6 or mTOR inhibitors. None of the Black pts with PIK3CA mutations were enrolled in clinical trials vs. 11.5% of White pts. Black pts with ER+/PR+/HER2- tumors were more likely to have CCND1 copy number variation (cnv) (odds ratio (OR) 2.4, 95% confidence interval (CI) 1.1-5.4, p=0.030) when compared with White pts. Black pts with PR- tumors were more likely to have de novo metastatic disease (OR 3.4, 95% CI 1.1-10.8, p=0.034) and GATA3SNV (OR 3.5, 95% CI 1.04-11.6, p=0.044). KRAS cnv was more common in White PR- pts (HR 2.9, CI 1.02-8.3, p=0.045). There were significant differences in OS between Black and White pts with ER+/PR+/HER2- tumors (median OS of 25 vs. 32 months, respectively) and for Black and White pts with ER+/PR-/HER2- MBC, (median OS of 9.1 vs. 21 months, respectively, log-rank test p=0.00093). Conclusions: To our knowledge, this is the largest clinicogenomic dataset comparing genomic alterations and targeted treatment use by race in MBC. We identified significant disparities in the use of PI3K inhibitors for Black pts while other drugs that do not require genomic profiling were similarly utilized. OS and clinical trial enrollment disparities are consistent with prior findings and must continue to be addressed. Further research is needed to validate these findings, elucidate the factors contributing to these disparities, and explore interventions to improve racial disparities in use of precision medicine therapies and enrollment in clinical trials.

Toxic element characterization against a typical high geology background: Pollution enrichment, source tracking, spatial distribution, and ecological risk assessment

The geological environment determines the initial content of various elements in soil, while the late input of toxic elements produced through weathering and leaching is a persistent threat to food security and human health. In this study, we selected the Lou Shao Basin, a black rock system background, and combined geostatistical analysis and multivariate statistics to quantify the specific contribution of weathering of the black rock system, and to analyze the source traces, spatial distributions, and ecological risks of the soil toxicity of elements. The results show that the soils in the study area are acidic, which is related to the weathering of sulfides in the black rock system. The concentrations of most elements in the soil were determined to exceed the soil background values, and the Cd, Se and N contents, exceeded more than five times, especially Se, Mo nearly as high as 13 times. Strong positive correlation between Se, Cu, V and P, low correlation between N and Se, Cu, V, P, Ni and Cd.72.52%, 43%, 77.79%, 82%, 77%, and 44.1% of Cd, Se, Ni, Cu, B, and Mo came from the black rock system, respectively, which were greatly affected by geogenic weathering; V, Zn, Pb, and As are mainly from biomass burning sources; N and P are mainly from agricultural surface sources. Comparison found that the Cd and Se elements in the rocks in the study area were 16.78 times and 1.36 times higher than the world shale average, respectively, and need to pay attention to the weathering process of the two, and the spatial distribution of the 12 elements in soils showed a striped and centralized block distribution pattern, specifically around the distribution of carbonate and metamorphic rocks and other high-geology blocks. The ecological risk results showed that Cd was the main element causing high ecological risk, followed by Se and N, which were at moderate to high ecological risk levels, and Se and N showed similar ecological risk patterns, which may be related to the fact that selenium can promote the uptake and transformation of nitrogen. The present results add to the endogenous sources of toxic elements, quantify the source contributions of toxic elements in soils with high geologic backgrounds, fill this knowledge gap, and provide new insights for pollution control and ecological protection in areas with high geochemical backgrounds.

Exact massless spinor quasibound states of Schwarzschild black hole

In this work, we investigate the behavior of massless spin 12 field by working out the Dirac equation in a curved static spherically symmetric Schwarzschild space-time. Detailed derivation of novel exact massive and massless scalar quasibound state in Schwarzschild black hole background is presented in this work. After decoupling the Dirac equation, we successfully solve both of the angular and radial parts, respectively in terms of spin weighted Spherical Harmonics and Confluent Heun functions. With the exact radial wave solution in hand, applying its polynomial condition leads to the discovery of the quantized energy levels expression. We found that the massless spinor field around the Schwarzschild black hole has complex valued energy levels, in contrast to the purely imaginary for a massless boson around the same black hole. In the last section, the Hawking radiation distribution function is derived via Damour-Ruffini method and the Hawking temperature is obtained.

Influence of different printing orientations and post-polymerization time on the translucency of three-dimensional (3D) printed denture base resins.

To evaluate the effect of different printing orientations and post-polymerization time with thermal cycling on the translucency of 3D-printed denture base resins. Heat-polymerized (HP) acrylic resin specimens were fabricated and 3D-printed denture base materials (NextDent, ASIGA, FormLabs) were printed with different printing orientations (0, 45, 90 degrees) and subjected to different post-polymerization times (15-, 30-, 60-, and 90-min). All specimens were polished and immersed in distilled water for 1day at 37°C. CIEDE2000 was used to measure the translucency parameters (TP00) before and after thermal cycling (5000 cycles) recording the color parameters (L*, a*, b*) against a black and white background using a spectrophotometer. k-factors ANOVA followed by post hoc Tukey's test (α=.05) was performed for statistical analysis. The k-factors ANOVA test showed a significant effect of resin material, post-polymerization time, and printing orientation on translucency (p<0.001). In comparison to HP, all 3D-printed resins showed lower translucency with all post-polymerization times and printing orientation (p<0.001) except FormLabs resin (p>0.05). For all 3D-printed resins, the translucency increased, with increasing the post-polymerization time (p<0.001) and 60- and 90-min showed the highest translucency. For printing orientation, 90 and 45 degrees significantly showed high translucency in comparison to 0 degrees (p<0.001). FormLabs showed significantly higher translucency when compared with NextDent and ASIGA per respective printing orientation and post-polymerization time. The translucency significantly decreased after thermal cycling for all tested resins (p<0.001). The findings of this study demonstrated that the translucency of 3D-printed resins is influenced by the printing orientation, post-polymerization time, and resin type. As a result, choosing a resin type, and printing orientation, with a longer post-polymerization time should be considered since it may improve the esthetic appearance of the 3D-printed resins.