bluuebunny/crossref_metadata_2025 huggingface dataset:
Parallel mechanisms signal a hierarchy of sequence structure violations in the auditory cortex
Authors: Jamali Sara , Bagur Sophie , Bremont Enora , Van Kerkoerle Timo , Dehaene Stanislas , Bathellier Brice
Published: November 2024

The brain predicts regularities in sensory inputs at multiple complexity levels, with neuronal mechanisms that remain elusive. Here, we monitored auditory cortex activity during the local-global paradigm, a protocol nesting different regularity levels in sound sequences. We observed that mice encode local predictions based on stimulus occurrence and stimulus transition probabilities, because auditory responses are boosted upon prediction violation. This boosting was due to both short-term adaptation and an adaptation-independent surprise mechanism resisting anesthesia. In parallel, and only in wakefulness, VIP interneurons responded to the omission of the locally expected sound repeat at the sequence ending, thus providing a chunking signal potentially useful for establishing global sequence structure. When this global structure was violated, by either shortening the sequence or ending it with a locally expected but globally unexpected sound transition, activity slightly increased in VIP and PV neurons, respectively. Hence, distinct cellular mechanisms predict different regularity levels in sound sequences.
Molecular, Cellular, and Developmental Organization of the Mouse Vomeronasal organ at Single Cell Resolution
Authors: Hills Max , Ma Limei , Fang Ai , Chiremba Thelma , Malloy Seth , Scott Allison , Perera Anoja , Yu C Ron
Published: November 2024

We have generated single cell transcriptomic atlases of vomeronasal organs (VNO) from juvenile and adult mice. Combined with spatial molecular imaging, we uncover a distinct, previously unidentified class of cells that express the vomeronasal receptors and a population of canonical olfactory sensory neurons in the VNO. High resolution trajectory and cluster analyses reveal the lineage relationship, spatial distribution of cell types, and a putative cascade of molecular events that specify the V1r, V2r, and OR lineages from a common stem cell population. The expression of vomeronasal and olfactory receptors follow power law distributions, but there is high variability in average expression levels between individual receptor and cell types. Substantial co-expression is found between receptors across clades, from different classes, and between olfactory and vomeronasal receptors, with nearly half from pairs located on the same chromosome. Interestingly, the expression of V2r, but not V1r, genes is associated with various transcription factors, suggesting distinct mechanisms of receptor choice associated with the two cell types. We identify association between transcription factors, surface axon guidance molecules, and individual VRs, thereby uncovering a molecular code that guides the specification of the vomeronasal circuitry. Our study provides a wealth of data on the development and organization of the accessory olfactory system at both cellular and molecular levels to enable a deeper understanding of vomeronasal system function.
Maternal obesity may disrupt offspring metabolism by inducing oocyte genome hyper-methylation via increased DNMTs
Authors: Chao Shuo , Lu Jun , Li Li-Jun , Guo Hong-Yan , Xu Kui-Peng , Wang Ning , Zhao Shu-Xian , Jin Xiao-Wen , Wang Shao-Ge , Yin Shen , Shen Wei , Zhao Ming-Hui , Huang Gui-An , Sun Qing-Yuan , Ge Zhao-Jia
Published: November 2024

Maternal obesity has deleterious effects on the process of establishing oocyte DNA methylation; yet the underlying mechanisms remain unclear. In the present study, we found that maternal obesity induced by high-fat diet (HFD) disrupted the genomic methylation of oocytes, and that at least a part of the altered DNA methylation was transmitted to the F2 oocytes and the livers via females. We further examined the metabolome of serum and found that the altered metabolites such as melatonin may play a key role in the disrupted genomic methylation in the oocytes of obese mice. We further found that exogenous melatonin treatment significantly reduced the hyper-methylation of HFD oocytes, and the increased expression of DNMT3a and DNMT1 in HFD oocytes was also decreased. To address how melatonin regulates the expression of DNMTs, the function of melatonin was inhibited or activated upon oocytes. Results revealed that melatonin may regulate the expression of DNMTs via the cAMP/PKA/CREB pathway. These results suggest that maternal obesity induces genomic methylation alterations in oocytes, which can be partly transmitted to F2 in females, and that melatonin is involved in regulating the hyper-methylation of HFD oocytes by increasing the expression of DNMTs via the cAMP/PKA/CREB pathway.
Gain Enhancement of Patch Antenna using Novel Glass Fiber Reinforced Polymer (GFRP) based Metasurface
Authors: Ali A. K. M. S. , Ahmed I. , Ali S. , Khalid M.
Published: November 2024

In this paper, the authors have presented extensive work done involving the design, simulation, development, and performance measurement of a novel Glass Fiber Reinforced Polymer (GFRP) composite-based metasurface patch antenna.  The authors have first designed GFRP composite-based metasurface patch antenna and simulated the design to measure its performance. Then the same antenna has been indigenously developed following the design specifications. Using the developed antenna, measurements have been recorded and performance has been analysed. Moreover, considering the significance of benchmarking, the authors have also compared the performance of the design and developed GFRP composite-based metasurface patch antenna results against the performance of Linear C-band patch antenna and a GFRP-based metasurface patch antenna. The results obtained through simulation and testing show characteristic similarity thus validating the approach adopted for the printing of copper on GFRP composite. The results also show that using GFRP composite as a metasurface on top of simple microstrip patch antenna results in an overall 39% gain enhancement compared to simple microstrip patch antenna gain.
Analytical Circuit-based Model for Low Thickness Tunable Metasurfaces Design
Authors: Legrand C. , Ropa P.
Published: November 2024

An analytical model of metasurfaces made of a rectangular array deposited on a low thickness (10-150 µm) grounded dielectric layer is presented. The surface impedance and the equivalent circuit are extracted from full wave simulations. Contrary to previous works on higher thickness metasurfaces, the absorption corresponds to the first resonance under the patch. The equivalent circuit is made of a parallel resonant RLC circuit in series with an inductance Ls. The analytical expressions of the RLC components and of the quality factors are established from the study of the influence of the different parameters. The inductance Ls is attributed to the non-metallized part of the mesh. The impedance of the resonant circuit expresses as the product of a proportionality factor, the impedance of a single patch and a periodicity factor. The model is validated on different examples. Specific properties are evidenced like the quasi-independence of the equivalent circuit resistance versus the length of the patch, the total absorption condition and the extension of the model to a two patches metasurfaces. Giving a better understanding of the role of the different parameters, the model is useful in view of new applications development notably electrically driven tunable metasurfaces.
Bilateral Bacterial Endogenous Endophthalmitis following Haemodialysis in a Diabetic Patient: A Case Report
Authors: Manade Varsha , Radhakrishnan OK , Rao Rutu , Singh Varsha , Anand Shailaja
Published: November 2024

Endogenous endophthalmitis, a severe infection originating from the bloodstream, can lead to blindness and is particularly dangerous for immunocompromised patients, including those with diabetes, cancer, or undergoing chemotherapy. This condition differs from exogenous endophthalmitis, which arises from external sources such as postoperative complications or trauma. Hereby, the authors present a case report of a rare instance of bilateral bacterial endogenous endophthalmitis in a 45-year-old male with multiple systemic co-morbidities. The patient experienced vision loss and photophobia; further investigation revealed septicaemia linked to an insitu haemodialysis catheter. Prompt treatment with intravenous antibiotics is crucial, and vitrectomy may also be considered. The present case is unique because, despite the infection originating in the bloodstream, the patient developed ocular symptoms first. A retrospective analysis revealed the primary source of the infection, highlighting the importance of a thorough examination.
Recent Advances in Non Surgical Rehabilitation Approaches for Medial Collateral Ligament Injuries: A Narrative Review
Authors: Chauhan Muneesh , Verma Rituraj , Zafar Shahiduz , Agarwal Shagun , Khan Abdur Raheem
Published: November 2024

The Medial Collateral Ligament (MCL) is frequently injured, particularly in athletes involved in contact sports. Recent advancements in non surgical rehabilitation have shown promise in effectively treating MCL injuries, thereby avoiding the risks associated with surgical interventions. Cryotherapy remains the cornerstone of non surgical MCL rehabilitation, significantly reducing pain and inflammation. Ultrasound therapy has shown potential in promoting tissue healing and improving the range of motion. Low-level Laser Therapy (LLLT) and shockwave therapy have emerged as effective modalities for enhancing tissue repair and providing pain relief. Bracing plays a crucial role in providing stability and support, aiding the controlled rehabilitation process. Therapeutic exercises targeting the quadriceps and hamstrings are integral to restoring strength, flexibility and stability, thus facilitating the healing process. Despite these advancements, gaps remain in optimising the combinations and timing of these modalities. Future research should focus on comparing different rehabilitation protocols, evaluating long-term outcomes and exploring their costeffectiveness. This review underscores the importance of non surgical rehabilitation in achieving favourable outcomes for MCL injuries, contributing to the growing body of evidence supporting these approaches.
From Crisis to Diagnosis: A Case of Hypertriglyceridemic Pancreatitis as the First Clinical Presentation of Type 1 Diabetes
Authors: Vadivel Subashini , Kishore Sheetal Nandha , Dhadwad Jagannath S , Panchal Janvi
Published: November 2024

Acute Pancreatitis (AP) is a prevalent and rapidly progressive inflammatory disorder of the pancreas, often presenting with abdominal pain and elevated serum pancreatic enzymes. The present case report emphasises the crucial need for accurately diagnosing the underlying cause of Hypertriglyceridemic Pancreatitis (HTGP) in patients who present without any pre-existing co-morbidities. A 16-year-old female presented with a three-day history of generalised abdominal pain, vomiting and low-grade fever, with no comorbidities. Initial clinical assessment revealed signs of dehydration, tachypnoea, tachycardia and diffuse abdominal tenderness. Laboratory workups indicated a significant rise in amylase and lipase, hyperglycaemia, metabolic acidosis and pronounced Hypertriglyceridemia (HTG). Imaging studies corroborated the diagnosis of AP, revealing necrotic fluid collections. The patient was immediately started on plasmapheresis, aggressive intravenous fluid resuscitation, insulin infusion and supportive care, which included electrolyte correction, pain management and vigilant monitoring of vital signs. The autoantibody panel for type 1 diabetes, Antiglutamic Acid Decarboxylase antibodies (GAD) returned positive. Over the following days, the patient exhibited marked clinical improvement, with decreased abdominal tenderness, stabilisation of vital parameters and normalisation of biochemical abnormalities. Subsequent imaging confirmed the resolution of pancreatitis. Upon discharge, the patient was prescribed a regimen of insulin, statins, fenofibrate and saroglitazar for ongoing management of her lipid levels and diabetes. This case underscores that HTG may present as the first clinical manifestation of Type 1 Diabetes Mellitus. It also emphasises the critical importance of prompt and coordinated therapeutic interventions in managing HTGP, where early and effective treatment is crucial for optimising patient outcomes.
Evaluation of Physicochemical Characteristics and Sensory Qualities of Fruit Roll Ups Made from Watermelon
Authors: Muhamad Nur Farah Hani , Adzaly Noor Zainah , Kasran Madzlan , Hashim Hasnisa , Hassan Siti Nurathirah Abu , Moey Siah Watt , Chuang Teoh Chin , Shafie Zainun Mohd , Akbar Adawiyah , Isman Norman , Hashim Mohd Fakhri , Mohamad Hairiyah , Halim Khairol Nadia Abd , Fiteri Nurul Nabilah Mohd
Published: November 2024

Watermelon biomass can be categorised into flesh, seed, and rind. Although discarded, the rind is edible and nutritious.
Objective: The study aimed to optimise watermelon fruit rolls-up formulation combining the flesh and rind purees. F1 (80:0), F2 (70:10), F3 (60:20), F4 (50:30), F5 (40:40), F6 (30:50), and F7 (20:60) were formulated from watermelon flesh-to-rind purees.
Methodology: Samples were prepared by pasteurising the watermelon flesh and rind purees with a predetermined amount of ingredients at 90 °C for 5 min, then dried at 60°C for 11 hours, cut, rolled and packed in an aluminium polyethene bag until evaluation.
Results: There were significant differences in pH, total soluble solids (TSS), moisture content (MC), water activity (Aw) and thickness of the samples. It showed that the increase of watermelon flesh puree in the formulations reduced the pH value and thickness of the samples. By contrast, the increase in watermelon rind puree decreases the samples' TSS, MC and Aw values. For sensory acceptance, the F2 sample had the highest mean scores for colour, texture (chewiness), sweetness, sourness and overall acceptability, indicating it was the most preferred formulation among panellists.
Conclusion: Thus, watermelon rind may be employed in watermelon fruit roll-up formulations to improve their physicochemical and sensory properties.
Enhancing Indoor Environmental Quality in Ghanaian Public Health Facilities: Challenges and the Role of Automation Technologies
Authors: Afful Paul , Adjarko Harold , Gemadzi John , Ewudzie Job
Published: November 2024

Traditional methods of managing IEQ in public health facilities in Ghana tend to be reactive rather than proactive, often relying on manual interventions that may not adequately address the complex interplay of factors affecting the indoor environment. This study aimed to investigate the indoor environmental quality in public health facilities through automation technologies, emphasizing Esikado District Hospital and Shama Health Centre.
This study employed a mixed-methods research design incorporating qualitative and quantitative approaches. Analyses including descriptive statistics and documentation analyses were conducted to assess the existing legal framework.
The study revealed that there were no existing legal frameworks or regulations to govern IEQ standards in Ghana hence hospitals had to rely on international guidelines to maintain IEQ at the facilities assessed. Both hospitals had their CO2 (400 ppm & 270 ppm) and Air particulate (8.2µg/m³ for PM2.5 & 4.2 µg/m³ for PM2.5) within the acceptable limits according to international guidelines.
The study promotes well-structured policies that give environmental elements in hospital settings priority by highlighting the direct link between higher IEQ and improved health outcomes for both patients and staff.
The study also pointing out that there aren't many local laws controlling IEQ, the study promotes the creation of thorough legal frameworks that can guarantee constant compliance with IEQ requirements in public health facilities, eventually creating a more secure and comfortable medical setting.
The study concludes that regulations and legal frameworks must be formulated in the country to enforce healthcare facilities better to comply with acceptable IEQ limits in their facilities. Implementing IEQ-controlling automation technologies will go a long way in improving overall facility management and indirectly influencing patient recovery.
Improving the Rheological Properties of Water-based Drilling Muds Using Waste Glass Powder
Authors: Igbani S. , Akari Nelson Tombra , Peletiri S. P. , Ambaga J. J.
Published: November 2024

In this study, we examined the rheological characteristics of water-based drilling muds incorporated with waste glass powder (WGP) of eight different weights (0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, and 4.5 g). The waste glass powder was analysed using FTIR spectroscopy, SEM-EDS, XRD, and particle size analyser, to determine the specific components or compounds present, and the predominate particle size. The analyses showed that the waste glass powder mainly consisted of silicone oxides (SiO2), indicating that it is a pozzolanic material. Moreover, the dimensions of the particles had a substantial impact on the rheological characteristics. In addition, the study assessed the rheological characteristics of the prepared water-based drilling muds by employing a rotational viscometer. This involved measuring the gel strength at 10-second and 10-minute intervals, while keeping the rotational speed constant at 3 rpm. The investigation also recorded the viscosity and yield points at speed of 300 and 600 rpm. Furthermore, the investigation assessed the plastic viscosity, apparent viscosity, gel strength, and yield point for eight distinct amounts of waste glass powder under standard conditions. As a result, the plastic viscosity of the mud systems increased from 10 to 31 cP, and the apparent viscosity increased from 20 to 44.5 cP as the weight of the waste glass powder increased from 0 to 4.5 g in each of the formulated muds.  Furthermore, the highest plastic, and apparent viscosity values were averagely identified, and recorded as 30 and 45.7 cP with an optimal WGP concentration (3.5 g of WGP per 350 ml of deionised water). Whereas, the optimal GS was achieved at 5 and 8 lb/100 ft2 after 10 seconds and 10 minutes, respectively, when the dosage of WGP increased to 2.5 g. Also, as the concentration of WGP reached 4.0 g, the YP dropped from 35 to 8 lb/100 ft2 compared to the YP at a WGP concentration of 3.5 g. Correspondingly, the viscosity and yield point at which the gel solidifies rose as the concentration of waste glass powder increased. Environmentally, utilising waste glass powder to enhance the rheological characteristics of water-based drilling mud has the potential to mitigate the glass waste disposal issues, to the environment, and offer a feasible substitute for commercially accessible additive. This study offers vital insights into the alternative and efficient utilisation of waste glass powder in drilling the conductor and surface interval of a wellbore.
Assessing Multi-element Pollution in Artisanal Gold Mining Areas: A Case Study of Koma Bangou (Niger)
Authors: Abdoulatif ABASS SALEY , Mahamadou SALEY , Mohamed MOUNKAILA , Ibrahim ELHADJ DAOU , Maarouhi INOUSSA Maman
Published: November 2024

Artisanal gold mining in Niger began in Koma Bangou following the 1984’s drought, followed by poor harvests and famine in Niger. Gold panning had been going on at Koma Bangou since 1984, with the introduction of ore leaching in 2009. The aim of this work was to assess the multi-element pollution generated by ore processing at Koma Bangou. Geochemical data acquired with portable XRF analyzer, corrected with ICP-MS data, were used to assess the global pollution level in As, Cr, Cu, Mn, Pb and Zn using the pollution load index and the local soil-geochemical background data from Koma Bangou. Multi-element pollution generated by the ore processing was identified at the ore processing sites. It was extremely high in the acidification waste (PLIMean = 5.35), and moderately high in the cyanidation waste (PLIMean = 1.98) and the cyanidation area soils (PLIMean = 1.66). The perimeter soils (PLIMean = 0.47), located far from the cyanidation sites were not polluted. Multi-element pollution at the Koma Bangou cyanidation sites is anthropogenic, due to the use of chemicals in hydrometallurgical processing and the discharge of tailings into the environment. This pollution adversely affects the environment and the surrounding ecosystems. This can have an impact on human health through domestic and agricultural use of polluted soil and water.
Within a hair's breadth of buying the product: The impact of tangible and intangible bodily cues of contamination: The role of disgust and mental imagery
Authors: Gérard Jessica , Helme‐Guizon Agnès
Published: June 2018

In most retail environments, customers can handle products. However, the downside of this freedom to touch products is product contamination. The objectives of this paper are threefold: (a) to examine the effects of contamination cues (tangible vs. intangible) on consumer responses; (b) to show the mediating role of contamination, disgust, and mental imagery; and (c) to assess the robustness of the results on three product categories for different levels of contact intimacy. Three experimental laboratory studies on different product categories (a book [n = 95], T‐shirt [n = 118], and apple [n = 102]) showed that tangible contamination cues decreased product evaluation and purchase intentions more than intangible contamination cues did. Moreover, contamination, disgust, and mental imagery mediated the effects of contamination cues on product evaluation and purchase intention. The findings provide theoretical and practical insights to help researchers and retailers understand the effect of tangible contamination cues on consumer responses.
Short‐Fluorinated iCVD Coatings for Nonwetting Fabrics
Authors: Soto Dan , Ugur Asli , Farnham Taylor A. , Gleason Karen K. , Varanasi Kripa K.
Published: June 2018

Water repellency is often generated by taking advantage of surface textures and low surface energy coatings such as the one afforded by long perfluorinated side‐chains polymers. However, new regulations are phasing out these polymers because of their related health and safety hazard concerns. This is a particular challenge for water‐repellent fabrics as consumers expect safer products with stable performance and new functionalities. In this work, an approach is developed that allows for iCVD deposition of durable, conformal short fluorinated polymers stabilized with a crosslinking agent. As a result, high hydrophobicity and low liquid adhesion are achieved simultaneously while maintaining initial substrate breathability. It is explained why this polymeric coating—1H,1H‐perfluorooctyl methacrylate co divinylbenzene—exhibits remarkable hydrophobic properties amidst a wide range of other possible candidates. In order to further enhance the dynamic water repellency performance, the chemical treatment is combined with physical texturing—obtained through microsandblasting, a process particularly suitable for fabrics—thus making this combined approach a suitable candidate to meet the industrial needs. This work paves the way for the development of environmentally friendly, highly repellent coatings for large volume production and the application of roll‐to‐roll coating techniques, and multifunctionalization of fabrics and wearable devices.
Modifying Temperature Stability of (K,Na)NbO3 Ceramics through Phase Boundary
Authors: Lv Xiang , Wu Jiagang , Xiao Dingquan , Zhu Jianguo , Zhang Junwei , Zhang Xi‐xiang
Published: June 2018

(0.99‐x)(K0.5Na0.5)(Nb0.965Sb0.035)O3‐0.01SrZrO3‐x(Bi0.5Na0.5)ZrO3 ceramics are chosen as an example to illustrate the effects of phase boundaries on strain. Temperature‐dependent dielectric permittivity and convergent beam electron diffraction patterns confirm the multiphase coexistence of rhombohedral, orthorhombic, and tetragonal phases in the ceramics with x = 0.03–0.04. Intriguingly, the ceramics with x = 0.03 display improved temperature stability in strain, e.g., a high retention (≈95%) of unipolar strain at 180 °C and low variation of 24% at 20–180 °C. A mode is proposed to show how to effectively tailor the strain and consolidate its temperature stability in potassium sodium niobate‐based ceramics.
Are there health benefits of being unionized in late career? A longitudinal approach using HRS
Authors: Wels Jacques
Published: June 2018

Objective

To assess whether unionization prevents deterioration in self‐reported health and depressive symptoms in late career transitions.

Methods

Data come from the Health and Retirement Study (N = 6475). The change in self‐perceived health (SPH) and depressive symptoms (CESD) between wave 11 and wave 12 is explained using an interaction effect between change in professional status from wave 10 to wave 11 and unionization in wave 10.

Results

The odds of being affected by a negative change in CESD when unionized are lower for unionized workers remaining in full‐time job (OR:0.73, CI95%:0.58;0.89), unionized full‐time workers moving to part‐time work (OR:0.66, CI95%:0.46;0.93) and unionized full‐time workers moving to part‐retirement (OR:0.40, CI95%:0.34;0.47) compared to non‐unionized workers. The same conclusion is made for the change in SPH but with odds ratios closer to 1.

Conclusion

The reasons for the associations found in this paper need to be explored in further research.
Superprotonic Conductivity in Flexible Porous Covalent Organic Framework Membranes
Authors: Sasmal Himadri Sekhar , Aiyappa Harshitha Barike , Bhange Siddheshwar N. , Karak Suvendu , Halder Arjun , Kurungot Sreekumar , Banerjee Rahul
Published: June 2018

Poor mechanical stability of the polymer electrolyte membranes remains one of the bottlenecks towards improving the performance of the proton exchange membrane (PEM) fuel cells. The present work proposes a unique way to utilize crystalline covalent organic frameworks (COFs) as a self‐standing, highly flexible membrane to further boost the mechanical stability of the material without compromising its innate structural characteristics. The as‐synthesized p‐toluene sulfonic acid loaded COF membranes (COFMs) show the highest proton conductivity (as high as 7.8×10−2 S cm−1) amongst all crystalline porous organic polymeric materials reported to date, and were tested under real PEM operating conditions to ascertain their practical utilization as proton exchange membranes. Attainment of 24 mW cm−2 power density, which is the highest among COFs and MOFs, highlights the possibility of using a COF membrane over the other state‐of‐the‐art crystalline porous polymeric materials reported to date.
Control charts with random interarrival times between successive samplings
Authors: Koutras Markos V. , Rakitzis Athanasios C.
Published: June 2018

In the classical setup used in process monitoring, the times between the collection of successive plotted samples are considered as nonrandom. However, in several real‐life applications, it seems plausible to assume that the time needed to collect the necessary information for plotting a point in the control chart has a stochastic nature. Under this scenario, instead of focusing on the number of points plotted on the chart until an out‐of‐control signal is initiated, the appropriate statistic to look at is the total time until a signal is generated. If we denote by L the run length of a control chart and by Yt,t = 1,2,…, the times between successive plotted points, then the compound random variable
expresses the time to signal of a monitoring scheme, under a particular sampling policy. In this paper, we illustrate how SL can be exploited to study various charts that are suitable for monitoring Poisson observations. We provide some results for the exact distribution of SL that may facilitate the task of the performance assessment of a control chart with random plotting times; illustrations and several numerical comparisons that are useful for quality control experts who wish to practice them are presented, and finally, an illustrative example elucidating the implementation of the proposed model is also provided.
Social Justice and Water Rates: Impacts of Rate Design on Low‐Income Customers
Authors: Clumpner Greg
Published: June 2018

When it comes to fairness to customers, water utilities need to consider the political, legal, and technical components of their rate design.
From Tetraphenylfurans to Ring‐Opened (Z)‐1,4‐Enediones: ACQ Fluorophores versus AIEgens with Distinct Responses to Mechanical Force and Light
Authors: Liu Xia , Li Mengwei , Liu Meifang , Yang Qiuhua , Chen Yulan
Published: June 2018

Two aryl‐substituted tetraphenylfurans (TPF‐1 and TPF‐2) and the corresponding ring‐opened (Z)‐1,4‐enedione derivatives (TPBD‐1 and TPBD‐2) have been successfully synthesized. Although all the molecules adopt propeller‐like configurations, experimental results revealed that the tetraphenylfurans (TPFs) were aggregation‐caused quenching (ACQ) fluorophores whereas the 1,4‐enediones (TPBDs) were aggregation‐induced emission (AIE) active. Additionally, the TPFs and TPBDs exhibited contrasting “turn‐on” mechanochromic behavior, with an unusual blueshift of mechanochromic fluorescence for the TPFs and a remarkable redshifted mechanochromism for the TPBDs. Both of these solid‐state optical properties were proven to be highly dependent on the mode of molecular packing and substituent effects. In particular, in addition to the tunability of the fluorescent properties through aggregation and mechanical force, ground TPF‐1 was found to be efficiently sensitive to light. On the basis of these findings we constructed a smart film with ground TPF‐1 and demonstrated its utility in data encryption and decryption well controlled by UV light. Therefore, this work not only provides an insight into the mechanism of AIE as well as mechanochromic effects, but also paves the way towards the development of multifunctional stimuli‐responsive materials and devices.
Tungsten Borides: On the Reaction of Tungsten with Boron(III) Bromide
Authors: Henschel Anne , Binnewies Michael , Schmidt Marcus , Köppe Ralf , Burkhardt Ulrich , Grin Yuri
Published: June 2018

The crucible‐free reaction between heated tungsten wires and gaseous boron tribromide yields different tungsten borides. The experiments were carried out at various reaction temperatures and times, revealing the formation of W2B, WB and WB2 phases. The underlying reactions were analyzed by using thermodynamic model calculations. The stability of the gaseous tungsten bromides was evaluated using quantum chemical methods. While the developed synthesis of phase‐pure borides is only possible to a limited extent, it offers a potential route for a formation of protective coatings with high chemical and thermal resistance.
Stereocontrolled Photoinduced Electron Transfer in Metal‐Fullerene Hybrids
Authors: Stasyuk Anton J. , Stasyuk Olga A. , Filippone Salvatore , Martin Nazario , Solà Miquel , Voityuk Alexander A.
Published: June 2018

Photoinduced electron transfer in transition‐metal complexes linked to a fullerene moiety is of increasing interest. Recently, several stereoisomers of an Ir‐complex exhibiting configurational stability at metal center, which does not undergo epimerization have been synthesized (Angew. Chem. Int. Ed. 2017, 56, 2136). The presence of multiple electron donor and acceptor sites located at opposite ends with respect to the metallic center creates the prerequisites for the formation of entirely different charge transfer (CT) states. Here we report the results of quantum mechanical calculations and detailed analysis of excited‐state properties for all stereoisomers of the junction. We found that the stereoisomers demonstrate clearly different CT properties by photoexcitation. The found photo‐stereospecific effects can be used to design new hybrids with a different type of photoinduced CT state, exhibiting dissimilar activity in photocatalysis.
Surrogate‐based visualization and sensitivity analysis of coronary stent performance: A study on the influence of geometric design
Authors: Ribeiro Nelson S. , Folgado João , Rodrigues Hélder C.
Published: June 2018

The main goal of this numerical study is to assess the impact of geometric design perturbations on the performance of a representative coronary stent platform. In this context, first, a design parameterization model was defined for the stent under study. After, a set of metrics characterizing stent performance, namely, vessel injury, radial recoil, bending resistance, longitudinal resistance, radial strength, the risk of fracture, prolapse index, and dogboning were evaluated within the context of a finite element analysis. Afterwards, accurate surrogate models were developed, using the efficient global optimization algorithm, as predictive tools in the execution of tasks that normally require a high number of model evaluations, such as global sensitivity analysis and visualization. In the end, the dependence of the output response surfaces on the geometric parameters was mechanically interpreted, which allowed us to understand the complex interplay that exists between the considered design variables and the defined performance metrics.
Enhanced Thermochemical Water Splitting through Formation of Oxygen Vacancy in La0.6Sr0.4BO3−δ (B=Cr, Mn, Fe, Co, and Ni) Perovskites
Authors: Wang Lulu , Al‐Mamun Mohammad , Zhong Yu Lin , Liu Porun , Wang Yun , Yang Hua Gui , Zhao Huijun
Published: June 2018

Oxygen vacancies in catalyst systems play a crucial role in manipulating pivotal redox properties that are strongly dependent on the composition of the material. Herein, for the first time, experimental evidence of a linear correlation between the extent of oxygen vacancy formation in the La0.6Sr0.4BO3 (B=Cr, Mn, Fe, Co, and Ni) perovskite series and H2 generation in two‐step thermochemical water splitting is reported, with detailed materials characterization by means of thermogravimetric analysis, XRD, SEM, TEM, and energy‐dispersive X‐ray spectroscopy. Noteworthy O2 (718 μmol g−1) and H2 (514 μmol g−1) production was achieved by the La0.6Sr0.4CoO3 perovskite in the thermochemical water‐splitting process conducted between 1300 and 900 °C.
Multi‐Step Continuous Flow Synthesis of β/γ‐Substituted Ketones
Authors: Garbarino Silvia , Protti Stefano , Gabrielli Serena , Fagnoni Maurizio , Palmieri Alessandro , Ravelli Davide
Published: June 2018

The smooth preparation of β/γ‐substituted ketones has been carried out by using a three‐step continuous flow synthesis involving the initial photocatalyzed addition of an aldehyde onto phenyl vinyl sulfone. The resulting β‐ketosulfones were then elaborated in flow to prepare in situ an enone upon basic elimination of the sulfonyl group and then to give γ‐nitroketones, a 4‐chromanone, and β‐(3‐indolyl)ketones in moderate to good yields.
Measuring performance degradation of virtual machines based on the Bayesian network with hidden variables
Authors: Hao Jia , Zhang Binbin , Yue Kun , Wu Hao , Zhang Jixian
Published: June 2018

In the virtualized environment, multiple virtual machines (VMs) sharing the same physical host are vulnerable to resource competition, which may cause performance interference among VMs and thus lead to VM performance degradation. This paper focuses on measuring CPU, memory, I/O, and the overall VM performance degradation caused by the performance interference according to the properties in the runtime environment of VMs. To this end, we adopt Bayesian network (BN), as the framework for uncertainty representation and inference, and construct a VM property‐performance BN (VPBN) with hidden variables, which represent the unobserved performance degradation of CPU, memory, and I/O, respectively. Then, we present the method to measure performance degradation of VMs by probabilistic inferences with the VPBN. Experimental results show the accuracy and efficiency of our method.
An efficient and secure 3‐factor user‐authentication protocol for multiserver environment
Authors: Luo Min , Sun Aiying , He Debiao , Li Xiaohong
Published: June 2018

In the last decade, the number of web‐based applications is increasing rapidly, which leads to high demand for user authentication protocol for multiserver environment. Many user‐authentication protocols have been proposed for different applications. Unfortunately, most of them either have some security weaknesses or suffer from unsatisfactory performance. Recently, Ali and Pal proposed a three‐factor user‐authentication protocol for multiserver environment. They claimed that their protocol can provide mutual authentication and is secure against many kinds of attacks. However, we find that Ali and Pal's protocol cannot provide user anonymity and is vulnerable to 4 kinds of attacks. To enhance security, we propose a new user‐authentication protocol for multiserver environment. Then, we provide a formal security analysis and a security discussion, which indicate our protocol is provably secure and can withstand various attacks. Besides, we present a performance analysis to show that our protocol is efficient and practical for real industrial environment.
Systematic investigations of novel validity parameters in urine drug testing and prevalence of urine adulteration in a two‐year cohort
Authors: Kluge Johanna , Rentzsch Linda , Remane Daniela , Peters Frank T. , Wissenbach Dirk K.
Published: June 2018

Urinalysis is well established for drug screening. Various methods of urine adulteration such as dilution, addition of oxidative/reductive chemicals or detergents, and handing over urine‐like fluids are used to circumvent a positive screen. Validity parameters such as determination of pH, gravidity, urine temperature, or testing for oxidative/reductive chemicals are therefore used to uncover adulterated urine specimens. However, synthetic urine (“fake urine”) has nowadays been used for manipulations, leading to inconspicuous results with common validity test systems.

Therefore, the aims of the study were (a) to evaluate additional validity parameters, (b) to evaluate the prevalence of urine adulteration, (c) to identify adulteration markers in purchased fake urine samples. Urine samples (n = 550) submitted for drug abstinence testing were analyzed by a standard urine liquid chromatography–tandem mass spectrometry (LC–MS/MS) screening approach using library‐assisted identification of 10 different endogenous biomolecules. The detection rates of biomolecules in authentic samples were phenylalanine (93.4%), tryptophan (97.1%), propionyl‐carnitine (67.1%), butyryl‐carnitine (99.6%), isovaleryl‐carnitine (92.8%), hexanoyl‐carnitine (91.0%), heptanoyl‐carnitine (97.1%), octanoyl‐carnitine (98.9%), and indoleacetylglutamine (98,2%). Phenylacetylglutamine was detected in each authentic sample. Based on the detection rates and measured creatinine levels, six manipulated samples were identified in this study. In two cases, fake urine was handed over, one time fake urine was most likely used for dilution. Once dilution with other fluids was used as adulteration method, while in another sample a detergent solution was handed over. Additionaly, one sample contained reactive chemicals. All fake urine samples were additionally identified by the detection of unique polyglycole patterns, which were observed in purchased fake urine samples.
NHC·Alane Adducts as Hydride Sources in the Hydrodefluorination of Fluoroaromatics and Fluoroolefins
Authors: Schneider Heidi , Hock Andreas , Jaeger Alma D. , Lentz Dieter , Radius Udo
Published: June 2018

We present herein the utilization of NHC‐stabilized alane adducts of the type (NHC)·AlH3 [NHC = Me2Im (1), Me2ImMe (2), iPr2Im (3), iPr2ImMe (4), Dipp2Im (5)] and (NHC)·AliBu2H [NHC = iPr2Im (6), Dipp2Im (7)] as novel hydride transfer reagents in the hydrodefluorination (HDF) of different fluoroaromatics and hexafluoropropene. Depending on the alane adduct used, HDF of pentafluoropyridine to 2,3,5,6‐tetrafluoropyridine in yields of 15–99 % was observed. The adducts 1, 2, and 5 achieved a quantitative conversion into 2,3,5,6‐tetrafluoropyridine at room temperature immediately after mixing the reactants. Studies on the HDF of fluorobenzenes with the (NHC)·AlH3 adducts 1, 3, and 5 and (Dipp2Im)·AliBu2H (7) showed the decisive influence of the reaction temperature on the H/F exchange and that 135 °C in xylene afforded the best product distribution. Although the HDF of hexafluorobenzene yielded 1,2,4,5‐tetrafluorobenzene in moderate yields with traces of 1,2,3,4‐tetrafluorobenzene and 1,2,4‐trifluorobenzene, pentafluorobenzene was converted quantitatively into 1,2,4,5‐tetrafluorobenzene, with (Dipp2Im)·AliBu2H (7) showing the highest activity and reaching complete conversion after 12 h at 135 °C in xylene. The HDF of hexafluoropropene with (Me2Im)·AlH3 (1) occurred even at low temperatures and preferably at the CF2 group with the formation of 1,2,3,3,3‐pentafluoropropene (with 0.4 equiv. of 1) or 2,3,3,3‐tetra‐fluoropropene (with 0.9 equiv. of 1) as the main product.
Attempted Resolution and Racemization of Beckmann‐Derived CTV‐Lactam and the Use of Chirabite‐AR® to Determine the Optical Purity of the Supramolecular Scaffold
Authors: Lutz Marlon R. , Ernst Elizabeth , Zeller Matthias , Dudzinski Jacob , Thoresen Peter , Becker Daniel P.
Published: June 2018

Chirabite‐AR was employed to differentiate enantiomers of the axially chiral cyclotriveratrylene (CTV)‐derived macrocyclic lactam with baseline separation of most of the proton NMR resonances enabling enantiomeric purity determination of this supramolecular scaffold. Attachment of menthyloxy acetic acid as a chiral auxiliary to the CTV‐Beckmann derived lactam afforded diastereomers that were enriched to a ratio of 87:13, as confirmed by both 1H NMR and single‐crystal X‐ray diffraction. Basic hydrolysis of the enriched diastereomeric mixture proceeded with rapid bowl inversion to yield racemic CTV‐lactam as confirmed by Chirabite‐AR NMR analysis. Density functional theory (DFT) calculations (M06 2X/6‐31G*) were performed on the crown and saddle conformers of the CTV‐lactam.
Investigation of a New Anion Exchange Membrane‐based Direct Ammonia Fuel Cell System
Authors: Siddiqui O. , Dincer I.
Published: June 2018

In this study, a direct ammonia fuel cell comprising of an anion exchange membrane‐based electrolyte is developed, built and tested in the laboratory for investigating the performance electrochemically. In this regard, the aqueous ammonia is used as a storage medium for unreacted fuel. With gaseous ammonia fuel, an open circuit voltage (OCV) of 280 ± 8 mV is obtained at an operating temperature of 25 °C and a pressure of 100 kPa (1 bar). Furthermore, the peak power density at ambient conditions with gaseous ammonia fuel is observed to be 6.4 ± 0.3 W m−2. The unreacted gaseous fuel is stored in the form of aqueous ammonia and the fuel cell performance is tested at varying storage reservoir temperatures between 25 °C and 65 °C. An OCV of 110 ± 3 mV and a peak power density of 0.72 W m−2 is observed at an aqueous fuel temperature of 25 °C. Increasing storage reservoir and humidifier temperatures are found to improve the fuel cell performance characteristics.
Ein Beitrag zur Traglastermittlung mit der Kinematischen‐Elemente‐Methode (KEM) bei Dilatanz
Authors: Gußmann Peter
Published: June 2018

Nach einer auf das Nötigste reduzierten Einführung in die Methode der Kinematischen Elemente (KEM) und deren Einordnung in die Schrankentheoreme der Plastizitätstheorie wird im Hauptteil ein einfaches Erdwiderstandsproblem betrachtet. Die in anschaulichen und leicht nachvollziehbaren Grafiken dargestellten Ergebnisse beleuchten fast alle Aspekte der oft kontrovers diskutierten Problematik (mit und ohne Dilatanz) der Schrankenlösungen.
One MRI‐compatible tDCS session attenuates ventromedial cortical perfusion when exposed to verbal criticism: The role of perceived criticism
Authors: Baeken Chris , Dedoncker Josefien , Remue Jonathan , Wu Guo‐Rong , Vanderhasselt Marie‐Anne , De Witte Sara , Poppa Tasha , Hooley Jill M. , De Raedt Rudi
Published: June 2018

Transcranial direct current stimulation (tDCS) is a potential treatment strategy for mood and anxiety disorders, but how this application may influence emotional processes, and whether this is related to individual characteristics, is not well understood. It has been proposed that perceived criticism (PC) may represent a vulnerability factor for the development of such mental illnesses. To decipher whether neural mechanisms of action of tDCS potentially differ depending on PC status (low vs. high), we evaluated mood and brain perfusion before and after applying MRI‐compatible tDCS, and after participants were exposed to verbal criticism in the scanner. Experimental design 30 healthy nondepressed females were included in a sham‐controlled crossover MRI‐compatible tDCS study. Brain perfusion was measured by means of arterial spin labeling (ASL) before and after tDCS applied to the left dorsolateral prefrontal cortex (DLPFC), and after hearing criticism. Before the experiment, all participants provided a rating of PC in their closest environment. Principal observations at the behavioral level, criticism made participants angrier. This was unrelated to the active or sham stimulation. After being criticized, females scoring high on PC had significantly decreased brain perfusion in the pregenual anterior cingulate cortex (pgACC) and medioprefrontal cortex (mPFC), after active tDCS but not sham. The decrease in pgACC/mPFC perfusion points to a significant impact of tDCS in brain areas related to stress responses and self‐referential processes, especially in females scoring high on PC, which has been shown to be related to vulnerability for mood and anxiety disorders.
Social health insurance vs private health insurance in China: Revisit crowd‐out effect based on a multiple mediation analysis
Authors: Zhang Ying , Su Anni , Liu Xiaoxing , Zhang Yue
Published: June 2018

Plenty of scholars have studied social health insurance and private health insurance in different economies, and many concentrate on crowd‐out effect. Different results have been presented due to various data choices and empirical methodologies, but few of them have revealed the transaction mechanism. We study this issue based on updated Chinese provincial panel data from 2002 to 2014 and improved methods. We focus on how the crowd‐out effect happens through 3 channels—saving, demographic factor, and medical expenditure using multiple mediator models. Besides, we apply Panel VAR model to study magnitude of the impact these 3 channels contribute, corporately and respectively. Results clearly show that social health insurance has crowd‐out effect in penetration but crowd‐in effect in density caused by different mediation variables. In addition, the 3 channels have shown lasting and dynamic influences on the crowd‐out (in) effect. Finally, our paper provides the anti‐crowd‐out solutions from both perspectives according to our empirical analyses. For social health insurance system, it is necessary to improve the efficiency and fairness of the funds. For the private health insurance companies, insurance products innovation and privilege policy should be made to decrease the negative impact of saving and medical service overuse.