2792 research outputs found
Sort by
Ethanol- and heat-mediated phase change from a kinetic (Z′ = 4) polymorph to a thermodynamic (Z′ = 1) polymorph for an N2,6-diaryl-1,3,5-triazine-2,4-diamine
No full textTwo polymorphs, α (Z' = 4) and β (Z' = 1), of an N2,6-diaryl-1,3,5-triazine-2,4-diamine derivative have been isolated at different times from ethanol solution. Significant 2 conformational variability in the five independent molecules is apparent. The molecular packing is distinct but features some commonalties such as the formation of eight-membered {···HNCN}2 synthons mediated by phenylamino-N H···N(triazine) hydrogen bonds and (external) supporting amino-N–H···C(phenylamino) contacts. The dimeric aggregates are connected into two-dimensional arrays via triazine-amino-N–H···O(methoxy) hydrogen bonds. In each crystal, the interactions involve chemically equivalent triazine-N, methoxy-O and amino-H atoms. However, the connections between layers is distinct, notably with superimposition of pairs of molecules via π···π stacking between all three aromatic rings in the α-form being restricted to π···π stacking between triazine rings only in the β-form. The experimental molecular structures have been subjected to a conformational analysis and compared to the geometry-optimised molecule. The MEP and NPA have been evaluated, and the molecular packing investigated by the analysis of the calculated Hirshfeld surfaces, interaction energies, NCI plots and energy frameworks. The kinetic α-polymorph crystallises with Z' = 4 and features expansive, stabilising π···π interactions in the molecular packing which is achieved by relatively unstable conformations of three of the four molecules. The αpolymorph is readily converted to the thermodynamic β-polymorph, which has the most stable molecular conformation, in solution, with the egress of time, and in the solid-state via heating of single crystals and powdered samples. The adoption of the crystal form results from an interplay between global molecular packing and stability of molecular conformation
Crystal structure of 2-({[5-(adamantan-2-yl)-2-sulfanylidene-1,3,4-oxadiazolidin-3-yl]methyl}amino)benzonitrile, C20H22N4OS
No full textC20H22N4OS, triclinic, P1 (no. 2), a = 6.8528(3) Å,
b = 11.3498(5) Å, c = 13.3896(9) Å, α = 114.083(5)°,
β = 104.326(4)°, γ = 90.369(3)°, V = 914.38(9) Å3
, Z = 2,
Rgt(F) = 0.0844, wRref(F2
) = 0.2217, T = 160 K.
CCDC no.: 221632
Consumers’ green purchase intention to visit green hotels: A value-belief-norm theory perspective.
No full textThe theory of planned behavior (TPB) has dominated the limited number of green hotel visitation studies; however, those studies’ findings are often inconclusive or even controversial. Thus, research needs to move beyond using the TPB to measure consumers’ intention and behavior, and to experiment with alternative theoretical frameworks to explain behavioral change. Valuebelief-norm theory of environmentalism (VBN) proposed that various facets of values can influence individuals’ beliefs, subsequently effecting their moral obligations, ultimately, their pro-environmental behaviors. Hence, this study aims to examine the relationship between value components (i.e., Biospheric, altruistic, collectivistic), beliefs (i.e., explicit and implicit attitude), norms (i.e., social and personal norm), and green purchase intention to visit green hotels
Implications of recruiting foreign nurses in local healthcare sector
No full textThe global landscape is currently facing a pronounced nursing deficit, with estimates suggesting a shortage of nearly 13 million nurses by 2030, as reported by the International Council of Nurses
Subcellular localization and functional characterization of paraneoplastic Ma Antigen 3 (PNMA3)
No full textPNMA (Paraneoplastic Ma Antigens) family consists of nineteen family members that are encoded by human genome (Pang et al., 2018). Gene expression studies showed that many of the family members are expressed in human brain and testes tissues. Furthermore, subset of the family members were reported to show abberant protein expression in tumors, including PNMA1, 2 and 3 proteins which have been found to express in breast, lung, and testicular cancers (Dalmau et al., 1999; Schüller et al., 2005) that are associated with Paraneoplastic Disorder in which the patients developed neurological conditions such as limbic, hypothalamic, and brainstem encephalitis. Other than their association with Paraneoplastic Disorder, the physiological functions of the PNMA family members remain elusive. However, few members of the PNMA family are known to be involved in the regulation of apoptosis signaling pathway. Among the family members that are known to positively regulate the apoptosis process are PNMA1, PNMA4 and PNMA5. In contrast, PNMA2 has been shown to be able to inhibit the apoptotic activity of PNMA4. However, the physiological function of PNMA3 remains unclear although bio-informative analysis has identified the presence of C2HC zinc finger domain at C-terminus of PNMA3 unique only to PNMA3 and not to the other PNMA family. In order to investigate the physiological function of PNMA3, the research project focuses on the cloning and expression of PNMA3 to determine the impact of overexpressed PNMA3 on cancer cells. Results from this investigation showed that PNMA3 similar to PNMA2 promotes cell viability and also its nuclear localization through the presence of a nucleus Socalization domain found at C-terminus of PNMA3 similar to that found on PNMA5. Interaction studies also have shown self-dimerization of PNMA3 which was prevalent in other PNMA families such as PNMA4 and PNMA5. Our interaction studies also identified the interaction of PNMA3 with PNMA2 and PNMA5 and we observed an increase in cell viability of PNMA2 and PNMA5 when co-transfected with PNMA3
Crystal structure of 5-(adamantan-1-yl)-3-[(4-{[2-(trifluoromethyl)phenyl]-methyl}piperazin-1-yl)methyl]-1,3,4-oxadiazole-2(3H)-thione, C25H31F3N4OS
No full textC25H31F3N4OS, monoclinic, P21/c (no. 14), a = 6.7323(1) Å,
b = 15.4999(2) Å, c = 23.7905(4) Å, β = 93.037(2)°, V = 2479.05(6) Å3, Z = 4, Rgt(F) = 0.0473, wRref(F2
) = 0.1394, T = 293 K.
CCDC no.: 224057
AI chatbots: Perspective from practitioners
Get PDFIn a recent advisory paper on the use of generative artificial intelligence (AI) in higher education (bit.ly/mqaai), the Malaysian Qualifications Agency (MQA) provided a comprehensive analysis of the potential benefits, drawbacks, and suggested approaches for higher education providers, academic staff, and students. The letter emphasizes the importance of maintaining academic integrity when utilizing generative AI in order to preserve the standard of education
Low dose and low dose rate radioluminescence dosimetry
No full textReview is provided of a number of low-dose, low dose rate situations that in study require advances in the development of dosimetric facilities. Using a clinical linac set up to provide doses down to the few mGy level, the performance of a real-time radioluminescence system has then been illustrated, accommodating pulsed as well as continuous dose delivery. The system gate times provide for tracking of the pattern of dose delivery, allowing detailed account of dose and dose-rate variations. The system has been tested in both x-ray and electron mode dose delivery
Pre-contrast CT calcium score correlation with significant risk factors for coronary artery disease
No full textComputed Tomography (CT) scan is one of the most widely used methods for evaluating the pre-contrast CT calcium scoring. This study aims to assess the correlation of pre-contrast CT calcium scoring with major risk factors for coronary artery disease (CAD). A descriptive study was conducted from Oct 2021 to Jan 2022 and included 109 patients. The mean age of the patients was 54.5 ± 14.1 (range 40–79) years old. The spreadsheet was used to gather the data via Picture Archive and Communication System (PACS) from the radiology department of King Salman Specialist Hospital, Hail (KSSHH). The study showed the percentage of male and female patients were 41.0% and 59.0%, respectively. More than zero calcium score among males was found to be 67.0%, whereas among females, it was at least 50.0%. The male group of 60–79 years old was found to be the most effected age group with more than zero calcium, while the female age group of 70–79 years showed the same zero calcium score. The percentage of calcium prevalence (score >0) in coronary arteries is affected by a number of risk factors. Coronary artery calcium (CAC) has emerged as a consistent means for assessing the risk of primary cardiovascular outcomes, especially for asymptomatic people. This study showed that the patient group with more than one risk factor for coronary heart disease had no evidence of calcium scoring. Study recommends to enlarge sample size in the coming future studies and to perform calcium scoring using CT scan before computed tomography angiofraphy (CTA)
Evaluation of CT dose and establishment of local DRLs for abdomen and pelvis examinations in hospitals in Taif City, Saudi Arabia
No full textThis study measures the CT dose of the abdomen and pelvic examinations for adult patients, as well as establishes the provincial diagnostic reference level (DRL) for hospitals in Taif city, Saudi Arabia. A total of 200 patients who underwent pelvis and abdomen examinations in two main hospitals in Taif city were selected for this study. The data were collected in a spreadsheet that records patients’ demographic data, exposure parameters and dose indicators such as dose length product (DLP) and volume computed tomography dose index (CTDIvol) for each examination. The patients’ average age and BMI were 37.3 years and 25.5 kg/m2, respectively. The mean DLP and CTDIvol for the pelvis were found to be 379.6 mGy-cm and 10.8 mGy, respectively, whereas the corresponding mean values for the abdomen were 369.5 mGy-cm and 11.5 mGy, respectively. The average effective dosages for the abdomen and pelvis in both hospitals were estimated to be 5.6 and 7.2 mSv, respectively. Based on the third quartile data of DLP and CTDIvol, this study suggests DRL for pelvic DLP and CTDIw are 402.5 mGycm and 21.8 mGy, respectively, whereas the respective values are 407.5 mGy-cm and 18.4 mGy for CT abdominal DLP and CTDIw. The present study reports lower values for effective dose and DRL when compared with earlier data available in the literature. However, this work suggests further studies with different kV stations on pediatric patients in the future