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Synthesis, characterization and antimicrobial analysis of metal-doped (Zn2+ and Ag+) brushite powder for bone regeneration
No full textYesBrushite, or Dicalcium phosphate dihydrate (CaHPO4⋅2H2O), is a well-known calcium phosphate (CaP) found in mineralized tissues and is utilized in medical treatment, particularly in bone powder for bone repair. Brushites with Zn2+ and Ag + ions concentration were synthesized in an aqueous solution using the conventional precipitation procedure. The synthesized brushites were characterized using techniques such as Fourier Transform Infrared Spectroscopy (FTIR), Powder X-ray diffraction (PXRD), Scanning Electron Microscopy (SEM), and bioassays were carried out to evaluate their antibacterial and antifungal activities. The alterations in PXRD and FTIR peak locations demonstrated that zinc and silver ions were effectively inserted into the brushite crystals.
Initial tests revealed that the powders were innocuous, which make them potentially beneficial for mineralized tissue engineering. These brushites exhibited remarkable antimicrobial activities. Zn-doped brushite completely controlled the growth of fungi namely Macrophomina phaseolina and Sclerotium rolfsii at a concentration of 0.0039 mg mL-1 while Ag-doped brushite completely arrested the growth of these fungi at 0.0312 and 0.0039 mg mL-1, respectively. Likewise, both the brushite exhibited remarkable antibacterial activity against Bacillus thuringiensis and moderate activity against Escherichia coli. Brushite compounds coupled with active metal ions, notably Ag+ and Zn2+, demonstrated promise as a distinct class of reactive materials for bone-related applications
High-durability, low-carbon, and low-cost nano-engineered concrete for marine concrete infrastructures
No full textYesTraditional concrete fulfills the mechanical requirements for marine infrastructures but lacks durability. This study employed nano-engineering techniques to address the durability challenges in marine concrete infrastructures by enhancing the chloride ions penetration resistance of low- and medium-strength concrete to be comparable to that of high-strength concrete without increasing cement dosage. Meanwhile, nano-engineered concrete is also expected to reduce the cost and CO2 emissions of concrete structures over the life cycle. For this purpose, the effect and mechanisms of nanofillers on the durability and microstructures of concrete were investigated. Moreover, CO2 emission, cost, and sustainability of nano-engineered concrete were evaluated. The results indicated that a small content of nanofillers remarkably inhibited the penetration of chloride ions into concrete, without increasing cement content. The chloride ions diffusion coefficient of concrete with nanofillers is as low as 3.9010-12 m/s, representing a reduction of 62.8% compared to blank concrete. Moreover, nanofillers effectively refine the concrete microstructure by inducing hydration products into short rods, blocks, and lamellae. The thickness of the interfacial transition zones (ITZs) between cement mortar and gravel as well as cement paste and river sand decreases by 40.7%-55.9%/36.1%-47.4%, respectively, while the porosity of ITZs decreases by 8.7%-17.8%, after adding nanofillers. In addition, the cost and CO2 emission of nano-engineered concrete during production are reduced by 18.1%-27.8% and 14.4%-22.2%, respectively, compared to traditional concrete. These findings demonstrate that nano-engineered concrete can serve as a viable construction material with reasonable strength, high durability, low carbon footprint, and low cost for marine concrete infrastructures.National Science Foundation of China (52308236, 52308243 and 52368031), Natural Science Joint Foundation of Liaoning Province (2023-BSBA-077), (LH2023E069), and the Major Science and Technology Research Project of the China Building Materials Federation (2023JBGS10-02).The full-text of this article will be released for public view at the end of the publisher embargo on 04 Dec 2026
Exploring Age – Transition Analysis as a tool for detecting the elderly
No full textNo"e growth of gender archaeology has improved the inclusion of female and juvenile narratives in archaeological discourse, enabling us to better understand interactions between groups defined by both social and physiological differences. "ere has been a
notable absence of elderly in research, however, that is not simply a question of attitudes but of methodological limitations. "e
emergence of biostatistics has offered novel ways to combat common issues such as age mimicry and avoid the problematic nature
of culturally loaded descriptive terminology. A test performed on Transition Analysis by Boldsen et al. (2002), generates individual
age estimates, which allow for better differentiation between individuals and age groups, such as the ‘45+ older adults’. Further
research into biostatistical methods will not only improve objectivity but bring much-needed attention to the elderly, including
their narrative into the investigation of family dynamics and adult-juvenile interactions
Energy poverty in African countries: An assessment of trends and policies
No full textYesEnergy poverty, understood as the lack of access to adequate and sufficient energy services, constitutes a severe development problem for the African continent. Even though several policies and alleviation measures have been implemented in the last few decades, African countries still face multiple challenges. Therefore, this paper aims to identify these challenges related to energy poverty alleviation in Africa and the suitable solutions to address them. Using a mixed methods approach, involving a bibliometric analysis and a survey of involved actors, the study identifies the current constraints, obstacles and measures to address the problem in African countries. Findings point out to governance-related issues, including corruption and poor policy implementation, as the most indicated reasons for energy poverty in Africa, more than technological, financial, and policy issues. The results also confirm the fact that energy poverty has various roots and addressing it needs to take into account challenges related to outdated infrastructure, limited accessibility, and high prices. Moreover, there is often a
lack of awareness about the benefits of renewable energy sources and energy-efficient practices, which suggests research in this field is also needed. The novelty of this study resides in the fact that it reviews the literature on the topic, describes its variables associated with the problem, and presents the views and perspectives from people familiar with the topic. The insights from this research can inform policymakers and infrastructure planners, helping them to prioritise investments and design interventions that address the root causes of energy poverty and its various manifestations.Andrea Gatto wishes to acknowledge funding from the Internal Faculty Start-Up Research Grant of Wenzhou-Kean University Project No. ISRG2023014. This paper is part of the "100 papers to accelerate climate change mitigation and adaptation " initiative led by the International Climate Change Information and Research Programme (ICCIRP)
Water dwelling: a European context: Later prehistoric water dwelling in the circum-Alpine region
No full textYe
Hypoxia-Responsive Prodrug of ATR Inhibitor, AZD6738, Selectively Eradicates Treatment-Resistant Cancer Cells
Get PDFYesTargeted therapy remains the future of anti-cancer drug development, owing
to the lack of specificity of current treatments which lead to damage in healthy
normal tissues. ATR inhibitors have in recent times demonstrated promising
clinical potential, and are currently being evaluated in the clinic. However,
despite the considerable optimism for clinical success of these inhibitors,
reports of associated normal tissues toxicities remain a concern and can
compromise their utility. Here, ICT10336 is reported, a newly developed
hypoxia-responsive prodrug of ATR inhibitor, AZD6738, which is
hypoxia-activated and specifically releases AZD6738 only in hypoxic
conditions, in vitro. This hypoxia-selective release of AZD6738 inhibited ATR
activation (T1989 and S428 phosphorylation) and subsequently abrogated
HIF1a-mediated adaptation of hypoxic cancers cells, thus selectively inducing
cell death in 2D and 3D cancer models. Importantly, in normal tissues,
ICT10336 is demonstrated to be metabolically stable and less toxic to normal
cells than its active parent agent, AZD6738. In addition, ICT10336 exhibited a
superior and efficient multicellular penetration ability in 3D tumor models,
and selectively eradicated cells at the hypoxic core compared to AZD6738. In
summary, the preclinical data demonstrate a new strategy of tumor-targeted
delivery of ATR inhibitors with significant potential of enhancing the
therapeutic index.University of Bradford STARTER Fellowshi
Roman auxiliary fort in Pojejena (Caraș-Severin County, Romania). The results of non-invasive and archival research (2017-2019)
Get PDFYesA non-destructive survey conducted in 2017–2019 in
the proximity of the auxiliary fort brought forth new data regarding
the military base on the bank of the Danube, in the frontier zone
between the Roman provinces of Moesia Superior and Dacia
Inferior. It became clear that the previously acknowledged large
stone fort was preceded by an unknown small earth-and-timber
fort likely dated to the late 1st – early 2nd century.
Analysis of the internal planning of the large fort, as well as the
results of test trenching near the East Gate not only allowed to
verify some geophysical results but also gave insight into the
chronology of the large fort and contributed to the discussion of
the changes to the fort’s garrison. The evidence shows that the
base functioned until the 260s CE, and while the Roman military
was probably present in the area at some point in the 4th century,
it was a relatively short episode during an attempt to reconquer
the Dacian riverbank
Shear performance of poplar LVL beams with a hole in bending-shear spans
No full textYesTo investigate the shear performance of poplar laminated veneer lumber (LVL) beams with holes in bending-shear spans, six specimens were designed and tested by four-point bending tests. Among these, five specimens were provided with a single hole of varying diameter-to-height ratio in the bending-shear span and two of these beams were also reinforced with circumferential carbon fiber reinforced polymer (CFRP) wrap layers. Furthermore, a 3D finite element models for poplar LVL beams with a hole were established, based on the extended finite element method (XFEM) using ABAQUS software. The validated model was utilized to conduct parametric studies on the diameter-to-height ratio, the hole shape, and the vertical eccentricity ratio. A simplified theoretical analysis for predicting the cracking and ultimate loads for LVL beam with a hole was also proposed. The results indicated that beams without a hole failed due to bending, characterized by mid-span tension cracks, whereas beams with a hole exhibited shear failure along the beam's grain direction due to stress concentration around the holes. The maximum normal tensile strain perpendicular to grain around the hole had an angle of 45° or 225° relative to the beam's longitudinal axis, consistent with the crack initiation angle. As the diameter-to-height ratio increased, the cracking and ultimate loads of beams with a hole decreased, indicating more brittle failure characteristics. The circular hole beam showed significant improvements in cracking and ultimate loads compared with the square hole beam with side length equal to the diameter of the circular hole. When the hole center's vertical eccentricity was in the compression zone, an increase in vertical eccentricity led to enhancements in both the cracking load and ultimate loads. Wrapping the beam with CFRP sheet around the hole effectively mitigated crack propagation, enhancing the load-bearing capacity of beams. The simplified formulas provided accurate prediction for the ultimate load, but highly overestimated the cracking and ultimate loads for poplar LVL beams with a hole. The research findings can be provided as a technical support for the design and application of LVL beams with holes
Experiences of Fasting during Ramadan in British Muslims: Psychological, Social and Health Behaviour
No full textYesRamadan is a month-long religious festival observed by Muslims worldwide, characterised by intermittent fasting. This qualitative study addressed the need to understand how fasting is experienced by Muslims residing in Western cultures, aiming to inform policies that create a more supportive environment. Practicing Muslims, both men and women, were recruited in the North of England in the United Kingdom (UK). Data were collected by individual interviews (N=7) and focus group discussion and then analysed using Social Ecological Theory as a framework. Fasting was managed at the individual level through instrumental food choice and eating practices, and by adapting sleep routines. Disrupted sleep routines posed a challenge for those who had to adhere to Western working schedules, leading to perceived detriments to cognitive function and mood. The sense of belonging associated with Ramadan was seen as a motivating factor for fasting. Breaking the fast (Iftar) was marked by social activity and the availability of traditional fried foods. Participants identified the wider Western culture and environment as challenging for those who are fasting. These findings imply a need for policies that enable flexible working practices for Muslims during Ramadan
Volumetric printing and non-destructive drug quantification of water-soluble supramolecular hydrogels
No full textYesVat photopolymerisation 3D printing is being actively explored for manufacturing personalised medicines due to its high dimensional accuracy and lack of heat application. However, several challenges have hindered its clinical translation, including the inadequate printing speeds, the lack of resins that give soluble matrices, and the need for non-destructive quality control measures. In this study, for the first time, a rapid approach to producing water-soluble vat photopolymerised matrices and a means of non-destructively verifying their drug content were investigated. Volumetric printing, a novel form of vat photopolymerisation, was used to fabricate personalised warfarin-loaded 3D-printed tablets (printlets). Eight different formulations containing varying amounts of warfarin (0.5–6.0% w/w) were used to print two different sized torus-shaped printlets within 6.5 to 11.1 s. Nuclear magnetic resonance (NMR) spectroscopy revealed the presence of only trace amounts of unreacted acrylate monomers, suggesting that the photopolymerisation reaction had occurred to near completion. All printlets completely solubilised and released their entire drug load within 2.5 to 7 h. NIR spectroscopy (NIRS) was used to non-destructively verify the dose of warfarin loaded into the vat photopolymerised printlets. The partial least square regression model built showed strong linearity (R2=0.980), and high accuracy in predicting the drug loading of the test sample (RMSEP=0.205%). Therefore, this study advances pharmaceutical vat photopolymerisation by demonstrating the feasibility of producing water-soluble printlets via volumetric printing and quantifying the drug load of vat photopolymerised printlets with NIRS.Engineering and Physical Sciences Research Council (EPSRC) U