Synthesis of platencin core structures via twist-brendane

The formation of a twist-brendane via intramolecular enolate alkylation is described. Conversion of bicyclo[2.2.1]heptane scaffold present in this twist-brendane through a Grob-type fragmentation to unravel a functionalized bicyclo[2.2.2] system which contains all the necessary carbon atoms of the lipophilic core structure of nor -platencin, a platencin analogue is presented. Synthesis of core structure of platencin was also accomplished by extending this strategy to a starting material possessing a surrogate for the exocyclic methylene group

Management and Complications of Arnold Chiari Hydrocephalus at Tertiary Health Care Center

Objective: to investigate the role of CT and MRI in diagnosis of Arnold chiari malformation of hydrocephalus and its treatment with VP shunt along with complications. Study Design: Prospective study Place and duration: Department of Neurosurgery, DG Khan Medical College from May 4, 2018 to May 4, 2019. Methodology: Fifty patients of congenital hydrocephalus who were not treated previously were selected. Detailed history about disease and clinical examination of patients was performed. Follow ups were done at neurosurgery OPD. SPSS software for data analysis was used and mean ± SD, frequency and percentages were calculated for variables. P value ≤0.05 was considered as significant. Results: Treatment in case of congenital hydrocephalus as VP shunt, intra-aneurysmal coiling, excision of meningomyelocele with VP shunt and suboccipital craniectomy + upper cervical laminectomy (scucl) were observed as 10%, 6%, 8% and 8% respectively.  Twelve percent of patients were not treated. Conclusion: CT and MRI are the main diagnostic tools for diagnosis of Arnold chiari malformation and VP shunt is the treatment of choice. Among complications of VP shunt infection of shunt and shunt block are the main complications

Dynamics of learning motives and barriers in the context of changing human life roles

This paper promotes a theoretical discussion that focuses on the motives and barriers that make impact on adults learning as well as on their dynamics related to the change of social roles. The adult learning motives and barriers change and vary according to the prevailing social roles at different periods of one’s life. This dynamics of adult learning motives and barriers is mostly influenced by the importance and compatibility of acquired social roles, responsibility areas and spaces of a person and other factors. The qualitative data was gathered in March – April 2016 in Kaunas, Lithuania. The sample consisted of 30 narratives, written by informants, aged 35 to 65 years that were participating in professional training courses. There has been prepared 30 self-reflections that were analysed using content analysis. The analysis of empirical data shows that external learning motives and barriers prevail in the period when an individual is active in the labour market while the personal motives remain overshadowed. However, personal barriers prevail in the expression of learning barriers. This is influenced by the society’s attitude towards the performance of pupil and student roles and the value attitudes of surrounding people that partially control it

The ASR mechanism of reactive aggregates in concrete and its mitigation by fly ash: A critical review

Alkali-silica reaction (ASR) of reactive aggregates is a major durability concern of concrete. The use of fly ash as a supplementary cementing material (SCM) shows a reliable way to control ASR expansion. This paper investigates the recent findings on effects of coal fly ash as a SCM on ASR of reactive aggregates. ASR is the reaction of amorphous silica of aggregates with highly alkaline pore solution in the binder matrix producing an expansive gel. The use of fly ash as cement replacement reduces pH of the pore solution by alkali binding and thus reduces the aggregate dissolution rate and swelling pressure of the ASR gel. The efficiency of fly ash primarily depends on its chemical composition with low calcium fly ash being more effective in mitigation of ASR expansion. Based on the available literature, this paper also analyses the ASR mitigation mechanisms of fly ash and provides some recommendations for future research. The degree of aggregate reactivity measurement, effect of alumina in fly ash, swelling properties of ASR gel in presence of fly ash and the long-term alkali contribution of fly ash on ASR are of particular importance

Prediction of Concrete Compressive Strength Using Support Vector Machine Regression: Statistical Characterization, Model Performance, and Feature Importance Analysis

This study presents the development and evaluation of a machine learning–based framework for predicting the compressive strength of concrete using a Support Vector Machine (SVM) regression model. A comprehensive dataset comprising 1,133 concrete mix designs was employed, incorporating key material composition parameters, including cement, blast-furnace slag, fly ash, water, super-plasticizer, fine aggregate, coarse aggregate, and curing age. Prior to model development, extensive descriptive and advanced statistical analyses were conducted to examine the distributional characteristics, variability, skewness, and robustness of the input variables, ensuring a sound understanding of the data structure. The analysis revealed substantial variability in cementitious materials and curing age, highlighting the nonlinear and heterogeneous nature of concrete strength development. An ε-SVM regression model with a radial basis function kernel was implemented to capture these complex relationships. Model performance was assessed using an 80:20 train–test split and multiple statistical metrics, including mean squared error, root mean squared error, mean absolute error, mean absolute percentage error, coefficient of determination, and coefficient of variation of RMSE. The results demonstrate that the SVM model achieved strong predictive accuracy, with an R² value of 0.89, RMSE of 5.32 MPa, and MAPE of 11.38%, indicating reliable generalization to unseen data. Error analysis confirmed stable prediction behavior for most samples, with only a limited number of isolated outliers. Feature importance evaluation using univariate regression and a Relief-based algorithm identified cement content and curing age as the most influential parameters, followed by super-plasticizer and water content, in agreement with established concrete technology principles. Overall, the study confirms the suitability of SVM regression for concrete compressive strength prediction while emphasizing the importance of thorough data characterization, multi-metric evaluation, and feature interpretability for robust and physically consistent machine learning applications in civil engineering

Enterobacterial infection in Saudi Arabia: First record of Klebsiella pneumoniae with triple carbapenemase genes resistance

Introduction: Carbapenemase producing Enterobacteriaceae are emerging as important pathogens worldwide with serious effects on patients’ outcome. The study aimed to investigate the emergence of carbapenemases associated with enterobacterial infection in Western region of Saudi Arabia. Methodology: Clinical isolates from suspected patients with enterobacterial infection were investigated over a one-year period from four tertiary care hospitals of Makkah, Saudi Arabia. All isolates were identified using Vitek-2 system and then screened for potential carbapenemase production using disk diffusion test. Suspected isolates with reduced susceptibility to carbapenems were further investigated for blaNDM-1, blaKPC and blaOXA-48 resistant genes. Results: Out of 120 confirmed Enterobacteriaceae isolates, Klebsiella pneumoniae and Escherichia coli comprised the largest proportion (35% and 34.2%, respectively) of encountered infections. Twenty-six (21.7%) isolates showed resistance to carbapenems, the majority of which (21/26) were K. pneumoniae. Remarkably, 17 isolates carried triple resistant genes KPC/NDM-1/OXA-48 while the other 4 carried double resistant genes (KPC/OXA-48) or (NDM-1/OXA-48). The current study revealed that the mentioned triple resistance genes have the higher incidence with significant association risk among males (COR 4.5; CI: 1.9-17.3; P = 0.018), non-Saudi nationalities (COR 4.9; CI: 1.5-19.3; P = 0.003), ICU-obtained specimens (COR 3.6; CI: 1.5-8.4; P = 0.002) and blood specimens (COR 2.8; CI: 1.1-6.9; P = 0.02). Conclusion: Multidrug-resistant Enterobacteriaceae isolates in particular K. pneumoniae co-harboring KPC, NDM-1 and OXA-48 genes are emerging in Western region, Saudi Arabia. This is the first record of triple carbapenemase genes co-producing K. pneumoniae associated with enterobacterial infection

Unraveling a tumor type-specific regulatory core underlying E2F1-mediated epithelial-mesenchymal transition to predict receptor protein signatures

Cancer is a disease of subverted regulatory pathways. In this paper, we reconstruct the regulatory network around E2F, a family of transcription factors whose deregulation has been associated to cancer progression, chemoresistance, invasiveness, and metastasis. We integrate gene expression profiles of cancer cell lines from two E2F1-driven highly aggressive bladder and breast tumors, and use network analysis methods to identify the tumor type-specific core of the network. By combining logic-based network modeling, in vitro experimentation, and gene expression profiles from patient cohorts displaying tumor aggressiveness, we identify and experimentally validate distinctive, tumor type-specific signatures of receptor proteins associated to epithelial-mesenchymal transition in bladder and breast cancer. Our integrative network-based methodology, exemplified in the case of E2F1-induced aggressive tumors, has the potential to support the design of cohort- as well as tumor type-specific treatments and ultimately, to fight metastasis and therapy resistance

Multiple novel prostate cancer susceptibility signals identified by fine-mapping of known risk loci among Europeans

Genome-wide association studies (GWAS) have identified numerous common prostate cancer (PrCa) susceptibility loci. We have fine-mapped 64 GWAS regions known at the conclusion of the iCOGS study using large-scale genotyping and imputation in 25 723 PrCa cases and 26 274 controls of European ancestry. We detected evidence for multiple independent signals at 16 regions, 12 of which contained additional newly identified significant associations. A single signal comprising a spectrum of correlated variation was observed at 39 regions; 35 of which are now described by a novel more significantly associated lead SNP, while the originally reported variant remained as the lead SNP only in 4 regions. We also confirmed two association signals in Europeans that had been previously reported only in East-Asian GWAS. Based on statistical evidence and linkage disequilibrium (LD) structure, we have curated and narrowed down the list of the most likely candidate causal variants for each region. Functional annotation using data from ENCODE filtered for PrCa cell lines and eQTL analysis demonstrated significant enrichment for overlap with bio-features within this set. By incorporating the novel risk variants identified here alongside the refined data for existing association signals, we estimate that these loci now explain ∼38.9% of the familial relative risk of PrCa, an 8.9% improvement over the previously reported GWAS tag SNPs. This suggests that a significant fraction of the heritability of PrCa may have been hidden during the discovery phase of GWAS, in particular due to the presence of multiple independent signals within the same regio

Highway increases concentrations of toxic metals in giant panda habitat

The Qinling panda subspecies (Ailuropoda melanoleuca qinlingensis) is highly endangered with fewer than 350 individuals inhabiting the Qinling Mountains. Previous studies have indicated that giant pandas are exposed to heavy metals, and a possible source is vehicle emission. The concentrations of Cu, Zn, Mn, Pb, Cr, Ni, Cd, Hg, and As in soil samples collected from sites along a major highway bisecting the panda's habitat were analyzed to investigate whether the highway was an important source of metal contamination. There were 11 sites along a 30-km stretch of the 108th National Highway, and at each site, soil samples were taken at four distances from the highway (0, 50, 100, and 300 m) and at three soil depths (0, 5, 10 cm). Concentrations of all metals except As exceeded background levels, and concentrations of Cu, Zn, Mn, Pb, and Cd decreased significantly with increasing distance from the highway. Geo-accumulation index indicated that topsoil next to the highway was moderately contaminated with Pb and Zn, whereas topsoil up to 300 m away from the highway was extremely contaminated with Cd. The potential ecological risk index demonstrated that this area was in a high degree of ecological hazards, which were also due to serious Cd contamination. And, the hazard quotient indicated that Cd, Pb, and Mn especially Cd could pose the health risk to giant pandas. Multivariate analyses demonstrated that the highway was the main source of Cd, Pb, and Zn and also put some influence on Mn. The study has confirmed that traffic does contaminate roadside soils and poses a potential threat to the health of pandas. This should not be ignored when the conservation and management of pandas is considered

Monitor unit calculations for external photon and electron beams: Report of the AAPM Therapy Physics Committee Task Group No. 71

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134882/1/mp4244.pd