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1,25-dihydroxyvitamin Db3s gut receptor kinetics in Japanese quail and vitamin D metabolism in calcium-depleted rats
(Texas Tech University, 1981-08) Abel de la Cruz, Luis Andres
Not available
1,8-Dihydroxy Naphthalene—A New Building Block for the Self-Assembly with Boronic Acids and 4,4′-Bipyridine to Stable Host–Guest Complexes with Aromatic Hydrocarbons
(2023) Manankandayalage, Chamila P. (TTU); Unruh, Daniel K. (TTU); Perry, Ryan (TTU); Krempner, Clemens (TTU)
The new Lewis acid–base adducts of general formula X(nad)B←NC5H4-C5H4N→B(nad)X [nad = 1,8-O2C10H6, X = C6H5 (2c), 3,4,5-F3-C6H2 (2d)] were synthesized in high yields via reactions of 1,8-dihydroxy naphthalene [nadH2] and 4,4′-bipyridine with the aryl boronic acids C6H5B(OH)2 and 3,4,5-F3-C6H2B(OH)2, respectively, and structurally characterized by multi-nuclear NMR spectroscopy and SCXRD. Self-assembled H-shaped Lewis acid–base adduct 2d proved to be effective in forming thermally stable host–guest complexes, 2d × solvent, with aromatic hydrocarbon solvents such as benzene, toluene, mesitylene, aniline, and m-, p-, and o-xylene. Crystallographic analysis of these solvent adducts revealed host–guest interactions to primarily occur via π···π contacts between the 4,4′-bipyridyl linker and the aromatic solvents, resulting in the formation of 1:1 and 1:2 host–guest complexes. Thermogravimetric analysis of the isolated complexes 2d × solvent revealed their high thermal stability with peak temperatures associated with the loss of solvent ranging from 122 to 147 °C. 2d, when self-assembled in an equimolar mixture of m-, p-, and o-xylene (1:1:1), preferentially binds to o-xylene. Collectively, these results demonstrate the ability of 1,8-dihydroxy naphthalene to serve as an effective building block in the selective self-assembly to supramolecular aggregates through dative covalent N→B bonds.
1-D Fourier Ptychographic Microscopy
(2017-05) Alotaibi, Mohammed; Grave de Peralta, Luis; Bernussi, Ayrton
Fourier Ptychographic Microscopy (FPM) is a novel and promising phase-recovery imaging technique that can surpass Rayleigh resolution limit when imaging non-periodic samples. However, we show that in photonic crystal imaging applications the resolution limit of the FPM technique cannot surpass Rayleigh resolution limit. We present a comprehensive discussion of this loophole in the FPM technique and we discuss how this limitation can be overcome
1.54 Micrometer Emitter and Optical Amplifier Based on Er Doped InGaN/GaN
(The International Society for Optics and Photonics, 2010) Zavada, J. M.; Jiang, H.X.; Lin, J.Y.; Dahal, R.
1.54 Micrometer Emitters Based on Erbium Doped InGaN P-I-N Junctions
(American Institute of Physics, 2010) Zavada, J. M.; Jiang, H. X.; Lin, J. Y.; Ugolini, C.; Dahal, R.
11-th order of accuracy for numerical solution of 3-D Poisson equation with irregular interfaces on unfitted Cartesian meshes
(2023) Idesman, Alexander (TTU); Mobin, Mir Moniruzzaman (TTU); Bishop, J.
For the first time the optimal local truncation error method (OLTEM) with 125-point stencils and unfitted Cartesian meshes has been developed in the general 3-D case for the Poisson equation for heterogeneous materials with smooth irregular interfaces. The 125-point stencils equations that are similar to those for quadratic finite elements are used for OLTEM. The interface conditions for OLTEM are imposed as constraints at a small number of interface points and do not require the introduction of additional unknowns, i.e., the sparse structure of global discrete equations of OLTEM is the same for homogeneous and heterogeneous materials. The stencils coefficients of OLTEM are calculated by the minimization of the local truncation error of the stencil equations. These derivations include the use of the Poisson equation for the relationship between the different spatial derivatives. Such a procedure provides the maximum possible accuracy of the discrete equations of OLTEM. In contrast to known numerical techniques with quadratic elements and third order of accuracy on conforming and unfitted meshes, OLTEM with the 125-point stencils provides 11-th order of accuracy, i.e., an extremely large increase in accuracy by 8 orders for similar stencils. The numerical results show that OLTEM yields much more accurate results than high-order finite elements with much wider stencils. The increased numerical accuracy of OLTEM leads to an extremely large increase in computational efficiency. Also, a new post-processing procedure with the 125-point stencil has been developed for the calculation of the spatial derivatives of the primary function. The post-processing procedure includes the minimization of the local truncation error and the use of the Poisson equation. It is demonstrated that the use of the partial differential equation (PDE) for the 125-point stencils improves the accuracy of the spatial derivatives by 6 orders compared to post-processing without the use of PDE as in existing numerical techniques. At an accuracy of 0.1% for the spatial derivatives, OLTEM reduces the number of degrees of freedom by times compared to quadratic finite elements. The developed post-processing procedure can be easily extended to unstructured meshes and can be independently used with existing post-processing techniques (e.g., with finite elements).
13-93 bioactive glass/alginate composite scaffolds 3D printed under mild conditions for bone regeneration
(2017) Luo, Guilin; Ma, Yufei; Cui, Xu; Jiang, Lixin; Hu, Yang (TTU); Luo, Yanfeng; Pan, Haobo; Ruan, Changshun
Composite scaffolds of type 13-93 bioactive glass (13-93 BG) and sodium alginate (SA), denoted 13-93 BG/SA, in mass ratios of 0 : 4, 1 : 4, 2 : 4 and 4 : 4 were prepared for bone regeneration by 3D printing under mild conditions. All obtained scaffolds were completely interconnected. As the 13-93 BG/SA mass ratio increased from 0 : 4 to 4 : 4, the pore size improved from 340 ± 27 to 530 ± 27 μm, porosity increased from 65.5 ± 5.3 to 87.5 ± 3.9% and shrinkage ratios decreased by half. Moreover, 13-93 BG incorporation improved the compressive strength and modulus of the SA scaffold, achieving highest values of 16.74 ± 1.78 MPa and 79.49 ± 7.38 MPa, respectively, in 13-93 BG/SA with a 2 : 4 mass ratio. Furthermore, in vitro apatite mineralization, the release of bioactive ions (Mg2+ and SiO44−) and a weakly alkaline pH were exhibited by scaffolds containing 13-93 BG, which further promoted the attachment, proliferation and osteogenic differentiation of rBMSCs on composite scaffolds. As a result, 3D-printed 13-93 BG/SA scaffold was an ideal candidate for bone regeneration.
1967: The year that created ‘68 media perspectives and student outcries
(2011-05) Strong, Ryan R.; Wong, Aliza S.; D'Amico, Stefano; Fallwell, Lynne A.
In 1967, Italian students developed the principles and practices that led to the monumental events of '68. Students occupied faculty buildings and demonstrated in the streets of major Italian cities. Following every events local, national and political newspapers reported to their readers a very well thought out perspective. The perspective given to the reader was the major way many Italians learned of the Italian student movement. Therefore, newspapers played a major role in the perceived memory of sessantotto in the minds of Italians.
The 1988 Yellowstone Fires : The Response of the Elk and Bison Community
(1998-08) Apple, Tanya C.
1996 Lubbock Summer Rep
(1996-06) Department of Theatre and Dance - Texas Tech University; Wilkins, Peter; Kerns, Williams
1:1 technology initiative: A case study to determine the barriers of implementation in a rural school setting
(2012-12) Barnett, Shaun; Klinker, JoAnn F.; Duemer, Lee S.; Brown, Wendell J.
The purpose of this qualitative study is to explore the decisions necessary for superintendents of small rural schools who desire to implement a 1:1 technology initiative. Superintendents have an ethical obligation to their staff, their students, and to all stakeholders of the district, to use their resources wisely, to think outside of the box, and to create an environment that allows for the integration of technology into the curriculum. When implementing a 1:1 technology initiative, many barriers present themselves that must be considered when determining the path toward a 1:1 initiative. This study will center on the characteristics of transformational leadership that are exhibited by the superintendents being studied and the ethical decisions that are necessary when undertaking such an initiative. A superintendent, using transformational leadership with an ethical focus, must work to overcome the barriers associated with implementing a technology initiative. They must be leaders with a truly visionary approach to the future successes of their students and their schools. The literature reviewed for this study showed a consistent purpose for administrators to develop procedures for the implementation of technology into the school setting. The integration of technology into the school setting helps transform schools into an environment of learning by doing instead of a system of merely absorbing knowledge (Collins & Halverson, 2009). Further research is needed in the areas of financial considerations, appropriate professional development, and the impact a 1:1 initiative will have on high-stakes testing accountability.
1st International Space Ecology Workshop - Research Needs & Roadmap to the Future
(2023 International Conference on Environmental Systems, 2023-07-16) Escobar, Christine; Grubbs, Patrick; Lantin, Stephen; Shevtsov, Jane; Taub, Frieda; Damlo, Sherri
Self-sufficient life support systems will be crucial for meeting the physical and mental health needs of crew during long-term, deep space exploration missions and for maintaining a permanent human presence in space. Closing the material loop with food production and waste recycling is necessary to reduce reliance on Earth resupply. Closed ecological systems (CES) can utilize a combination of biological, ecological, and physicochemical processes to support human life. A space habitat can be considered an artificial ecosystem in which human beings exchange energy and material with other system components and their extraterrestrial environment. The inaugural International Space Ecology Workshop was held on October 22, 2022, to promote and organize CES research internationally and to reignite interest in the ecological systems approach to space life support. This workshop brought together engineers, space biologists, and ecologists to discuss the past, present, and future of CES that could enable indefinite, sustainable human exploration of space, as well as sustainable living on Earth. Specific workshop goals were to review research needs and knowledge gained to date, connect active professionals in the field, and plan next steps for closing knowledge and technology gaps. This paper summarizes the proceedings and a Space Ecology Roadmap for prioritizing and guiding future action.
The 2 × 2 Achievement Goals in Sport and Physical Activity Contexts: A Meta-Analytic Test of Context, Gender, Culture, and Socioeconomic Status Differences and Analysis of Motivations, Regulations, Affect, Effort, and Physical Activity Correlates
(MDPI, 2020) Lochbaum, Marc; Zanatta, Thaís; Kazak, Zişan
Approach-avoidance achievement goals are studied extensively in the context of competitive sports and physical activity, including leisure and physical education. Building upon past meta-analyses, the purpose of this quantitative review was to provide basic descriptive data, estimated means for testing of several research questions (i.e., context, gender, culture, and socioeconomic status), and meta-analyzing outcome correlates (i.e., self-determination constructs, affect, effort, and physical activity). A total of 116 studies up to 1 December 2018, met inclusion criteria. These 116 studies, totaling a sample size of 43,133 participants (M sample size = 347.85 + 359.36), from 22 countries with 92.7% of samples, are drawn from participants less than 30 years of mean age. From the 116 unique studies, nearly half (49.6%) were from a sport context and the rest from leisure-time physical activity (PA) (19.4%) and physical education (PE) (31.0%) contexts. A number of different analyses were conducted to examine our research questions. Support was found for several of our research questions: The mastery-approach goal was endorsed more than all the other goals, while sport participants endorsed the performance-approach goal more than PA and PE groups; females endorsed the mastery-avoidance goal more than males; more culturally individualistic countries endorsed the mastery-approach goal; and countries from lower socioeconomic and interdependent countries endorsed the mastery-avoidance goal than higher socioeconomic and independent countries. Concerning, the meta-analyzed correlates, most relationships were hypothesized through the performance-approach goal, and both avoidance goals appeared to be too similar in relationships with the correlates raising theoretical concerns. Overall, the mastery-approach goals had the most meaningful biased corrected effect size values (rc) with the outcome correlates, such as relative autonomy (0.47), intrinsic motivation (0.52), effort (0.40), positive affect (0.42), physical activity intent (0.38). Based on the present and past meta-analytic results, the 2 × 2 achievement goals as currently measured was questioned. Future research suggestions included fundamental questionnaire issues, the need for latent profile analysis or other more advanced statistics, and whether the 2 × 2 achievement goal framework is the most appropriate framework in physical activity contexts.
2 × 2 achievement goals profiles in Chilean competitive and recreational athletes: a first look
(2016) Lochbaum, Marc; Jean-Noel, Javan; Kazak Çetinkalp, Zişan; Vallejo-Reyes, Felipe Andrés; Mena Campbell, Jose
Purpose: was to examine the 2 × 2 achievement goal profiles of Chilean young adults regularly participating in competitive and recreational sport. Materials: participants were 108 female and 132 males who were recruited from the Valparaiso and Viña del Mar areas of Chile. Participants completed a valid and reliable measure of the 2 × 2 achievement goals referenced to sport participation. Results: indicated that the entire sample significantly ( p < .05) and very meaningfully (Hedges’ g range 1.13 - 2.91) endorsed the mastery-approach goal more so than the other three achievement goals. Male participants significantly ( p < .05) endorsed both approach goals and the mastery goal contrast more so than the female participants. These differences approached medium in meaningfulness (Hedges’ g range .40 - .46). Significant differences did not exist between competitive and recreational athletes on any of the achievement goals or goal contrasts. Confirming the lack of significant differences were the computed small to negligible in magnitude effect sizes. Conclusions: the present data were a first look into profiling sport participants on the 2 × 2 achievement goals in Chile. Given this sample of Chilean participants endorsed the performance goals far less than found in the sport psychology 2 × 2 achievement goal literature, more research is needed before these results are generalized to Chilean sport participants. Future research must also examine the relationships of antecedents and consequences to the 2 × 2 achievement goals to advance sport psychology in Chile.
2-Methoxyestradiol, a novel pharmacological inhibitor for Angiotensin Type I Receptor
(2012-05) Koganti, Sivaramakrishna; Thekkumkara, Thomas; Abbruscato, Thomas J.; Karamyan, Vardan; Liu, Xinli
Delayed onset of cardiovascular(CVD) disease among females is not well understood, but could be in part due to the protective effect of estrogen before menopause. Experimental studies have identified the angiotensin type I receptor (AT1R) as a key factor in the progression of CVD.In this study, we have examined the effects and mechanism of the estrogen metabolite, 2-Methoxyestradiol (2ME2), on AT1R expression.The study used rat liver epithelial cells as the primary cell model to determine the 2ME2 induced cellular signaling, the overall concept was further confirmed in rat aortic smooth muscle cells and further validated in vivo in an animal model of hypertension. When rat liver epithelial cells were exposed to 2ME2 for 24 hours, cells exhibited significant down-regulation of AngII binding and AT1R mRNA, independent of estrogen receptors (ERα/ERβ) with no change in receptor affnity.Significant inhibition of AngII mediated increase in intracellular Ca+2 and increased phopsphorylation of ERK1/2 were also observed.Similar analyses in stably transfected CHO cell lines with a constitutively active cytomegalovirus (CMV) promoter showed no change in AT1R expression suggesting the transcriptional regulation.2ME2 has been shown to bind specifically to endoplasmic reticulum bound G-protein coupled receptor 30(GPR30), activating matrix metalloprpteinases (MMPs) to induce epidermal growth factor receptor (EGFR) activation ultimately leading to AT1R down-regulation.2ME2 treatment showed significant down-regulation of systolic, diastolic and mean arterial blood pressure, as well as a decrease in body weight in spontaneously hypertensive rats (SHR).Consistent with the reduction in blood pressure, we observed AT1R protein and mRNA expression down-regulation in the renal cortical tissue. In summary, as AT1R plays a critical role in the control of cardiovascular diseases, 2ME2 induced changes in receptor expression may provide beneficial effects to the cardiovascular, as well as other systems.
200 Nanometer Deep Ultraviolet Photodetectors basen on AlN
(2011-07-12T18:36:20Z) Jiang, H.X.; Lin, J.Y.; Nakarmi, M.L.; Dahal, R.; Fan, Z.Y.; Li, J,
2003-2004 Mainstage and lab theatre seasons
(2003-04) Department of Theatre and Dance - Texas Tech University

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