bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of Zn1−xBaxO nanoparticles reinforced poly(vinyl alcohol) macromolecular nanocomposite films: Eco‐friendly integrated materials for optical systems
Authors: Chandrappa Halli , Bhajantri Rajashekhar Fakeerappa , Ismayil  , Ganesha Kaliyur Nanjundaiah
Published: July 2022

In this paper, we report the synthesis of Ba doped ZnO (Zn1−xBaxO, [x = 0.05]) nanoparticles (NPs) with a polycrystalline hexagonal wurtzite structure using chemical co‐precipitation method and prepared optically transparent, high refractive index polymer nanocomposite films by incorporating Zn1−xBaxO into poly(vinyl alcohol) (PVA) matrix. The average crystallite size of 104 nm was estimated by Scherrer's formula from X‐ray diffraction (XRD) patterns. The crystallinity of the composite film is significantly increased when Zn1−xBaxO NPs are added. The basic principles and theoretical aspects of scattering, transparency and refractive index of the composite structures are discussed. The formation of ZnBaO inter metallic bond was confirmed by the IR peaks that appear at the spectral wavenumbers (⁓596–608) cm−1. ATR‐FTIR spectral transmittance strongly proves the intermolecular interactions that occur in the composite film with molecular modification and various functional group impressions. UV–Vis absorption spectrum demonstrates a strong absorption edge around 379 nm owing to oxygen species corresponding to ZnBaO nanostructures in the composite films. The developed polymer composite films yielded strikingly higher RI value of ⁓(n = 2.5) having Abbe's number (υD = 10) with 57% plus transparency for 5 wt% NPs (ZBP‐3) with sufficiently low extinction coefficient values (k⁓10−4). Optical conductivity (σopt) was found to elevate from σopt ⁓ (4.465 × 1010) s−1 for pristine PVA to a σopt ⁓ (1.309 × 1012) s−1 for 5 wt% Zn0.95Ba0.05O filled composite films. Differential scanning calorimetry analysis showed a significant increase in the Tg value. The significant increase in Tm and Td > 311°C values indicates excellent thermal stability. Hence, the nanocomposite films demonstrated an integrated system of excellent refractive index, considerable visual transparency and excellent thermal stability, establishing their potential for use as a wider spectrum of optical system requirements.
Recent advancements in enzyme‐incorporated nanomaterials: Synthesis, mechanistic formation, and applications
Authors: Anboo Shamini , Lau Sie Yon , Kansedo Jibrail , Yap Pow‐Seng , Hadibarata Tony , Jeevanandam Jaison , Kamaruddin Azlina H.
Published: July 2022

Over the past decade, nanotechnology has been developed and employed across various entities. Among the numerous nanostructured material types, enzyme‐incorporated nanomaterials have shown great potential in various fields, as an alternative to biologically derived as well as synthetically developed hybrid structures. The mechanism of incorporating enzyme onto a nanostructure depends on several factors including the method of immobilization, type of nanomaterial, as well as operational and environmental conditions. The prospects of enzyme‐incorporated nanomaterials have shown promising results across various applications, such as biocatalysts, biosensors, drug therapy, and wastewater treatment. This is due to their excellent ability to exhibit chemical and physical properties such as high surface‐to‐volume ratio, recovery and/or reusability rates, sensitivity, response scale, and stable catalytic activity across wide operating conditions. In this review, the evolution of enzyme‐incorporated nanomaterials along with their impact on our society due to its state‐of‐the‐art properties, and its significance across different industrial applications are discussed. In addition, the weakness and future prospects of enzyme‐incorporated nanomaterials were also discussed to guide scientists for futuristic research and development in this field.
A Tumor‐Targeting Dual‐Stimuli‐Activatable Photodynamic Molecular Beacon for Precise Photodynamic Therapy
Authors: Tam Leo K. B. , He Lin , Ng Dennis K. P. , Cheung Peter C. K. , Lo Pui‐Chi
Published: July 2022

A multifunctional photodynamic molecular beacon (PMB) has been designed and synthesized which contains an epidermal growth factor receptor (EGFR)‐targeting cyclic peptide and a trimeric phthalocyanine skeleton in which the three zinc(II) phthalocyanine units are each substituted with a glutathione (GSH)‐responsive 2,4‐dinitrobenzenesulfonate (DNBS) quencher and are linked via two cathepsin B‐cleavable GFLG peptide chains. This tailor‐made conjugate is fully quenched in the native form due to the photoinduced electron transfer effect of the DNBS moieties and the self‐quenching of the phthalocyanine units. It can target the EGFR overexpressed in cancer cells, and after receptor‐mediated endocytosis, it can be activated selectively by the co‐existence of intracellular GSH and cathepsin B, both of which are also overproduced in cancer cells, in terms of fluorescence emission and singlet oxygen generation. The cell‐selective behavior of this PMB has been demonstrated using a range of cancer cells with different expression levels of EGFR, while the stimuli‐responsive properties have been studied both in vitro and in various aqueous media. The overall results show that this advanced PMB, which exhibits several levels of control of the tumor specificity, is a promising photosensitizer for precise antitumoral photodynamic therapy.
Azaborinine
Authors: Appiarius Yannik , Staubitz Anne
Published: July 2022

Der formale Austausch zweier benachbarter Kohlenstoffatome im klassischen Aromaten Benzol durch jeweils ein Bor‐ und ein Stickstoffatom liefert ein 1,2‐Azaborinin. Dieses weist im Vergleich zum aus alternierenden Bor‐ und Stickstoffatomen bestehenden Sechsring Borazin eine deutlich gesteigerte Aromatizität auf, was experimentell etwa durch eine Untersuchung der Bindungslängen, Resonanzstabilisierungsenergien, NMR‐Verschiebungen oder Reaktivitäten gegenüber Elektrophilen nachgewiesen werden konnte. Im Labor lassen sich monozyklische Azaborinine vor allem über Olefinmetathesen offenkettiger B,N‐Allylderivate und anschließende Aromatisierung herstellen, doch auch der Einbau in größere Systeme ist möglich. Sowohl monozyklische als auch polyzyklische Azaborinine weisen ein großes Anwendungspotential etwa in den Materialwissenschaften, der Pharmakologie oder der Analytik auf, da die polare B‐N‐Einheit eine Reihe neuartiger chemischer, physikalischer und optischer Eigenschaften induziert.
Der Einfluss von Mikroplastik auf Bodenlebewesen
Authors: Okoro Chidubem Laureen
Published: July 2022

In der vorliegenden Arbeit soll der Einfluss von Mikroplastik, welches durch Reifenabrieb von Kraftfahrzeugen entsteht, auf das Bodenlebewesen C. elegans untersucht werden.
Load balancing techniques for fog computing environment: Comparison, taxonomy, open issues, and challenges
Authors: Kashyap Vijaita , Kumar Ashok
Published: July 2022

Load balancing (LB) is nothing but the systematic distribution of load over different servers. The fog server is handling the maximum data of the cloud server to enhance the advancement of users' requests. The growth in data requests is escalating, and fog computing has intensified the accessibility of the data. Fog computing achieves many challenges according to the demands of the users, but even so, some challenges require more progress. The problem faced by fog computing is LB due to an increase in traffic on the network layer. Various LB techniques have already been proposed in the cloud layer, but until now they have only been in progress in the fog layer. Inefficient LB may cause a decrease in service quality, like delays in response time, processing time, security, and many more. In this survey, several algorithms have been discussed that are based on LB, which works out the issue of overloaded data on the network. Some parameters that authors have focused in LB are latency, bandwidth, deadlines, cost, security, execution time, and response time. Other parameters based on fault tolerance are also discussed with their quality parameter table and algorithm. In addition to this some of the limitations of the author's work, that is discussed in this article.
Preparation of antihypertensive peptides from quinoa via fermentation with Lactobacillus paracasei
Authors: Li Shuai , Du Gengan , Shi Jiajun , Zhang Lin , Yue Tianli , Yuan Yahong
Published: July 2022

Quinoa is a pseudo‐cereal that is rich in protein and an ideal source of antihypertensive peptides. In this study, quinoa flour was fermented with Lactobacillus paracasei CICC 20241 via solid fermentation to produce antihypertensive peptides. The peptides were isolated and purified by ultrafiltration and gel chromatography, and then identified by liquid chromatography−tandem mass spectrometry. A total of 91 peptides were identified. In addition, five potential angiotensin‐converting enzyme (ACE) inhibitory peptides were synthesized with reference to in silico analysis. Among them, NIFRPFAPEL and AALEAPRILNL had the greatest inhibitory effect, with an IC50 of 49.02 and 79.72 µM, respectively. Inhibition dynamics and molecular docking indicated that NIFRPFAPEL formed eight hydrogen bonds with ACE residues Tyr523, Arg522, Glu384, Glu143, Glu123, Thr92, Tyr62, and Trp59. NIFRPFAPEL exerted a competitive inhibitory effect by interacting with residues Tyr523 and Glu384 of pocket S1. AALEAPRILNL exerted a noncompetitive inhibitory effect by forming eight hydrogen bonds with the inactive ACE site residues Ser516, Glu403, Ser355, Glu143, ARG124, and Asn70. These results confirmed that quinoa is a potential material for antihypertensive functional foods, while NIFRPFAPEL and AALEAPRILNL could be used for the development of antihypertensive functional foods or drugs.
Screening of high lipid content and productivity of microalgae under photoautotrophic cultivation for biodiesel production
Authors: Jarungkeerativimol Paninee , Chonsongkram Jaruwan , Sappamongkolchai Werasit , Sultan Imrana Niaz , Tareen Afrasiab Khan , Parakulsuksatid Pramuk
Published: July 2022

Microalgae are globally accepted source of fatty acids (FA) due to their cell's potential to efficiently accumulate triacylglycerides which contain a significant amount of fatty acids for biodiesel production. This study aimed to screen nine (09) green microalgae strains in the laboratory for their high biomass and lipid productivity. Various microalgae strains were cultured at 30°C, with a light to dark ratio of 16:8 h (10–12 klux of light intensity) and aeration supplementation of 2% CO2 for longer period of time. The fatty acids of all microalgae species which showed growth potential under photoautotrophic cultivation had similar fatty acids found in palm oil. The selected strains of Ankistrodesmus sp. IFRPD 1061 and Chlorella sp. IFRPD 1092 were used due to their high lipid productivity content, were cultivated in 100 L NS III medium in an open raceway pond, aerated with 2% v/v CO2. The biomass concentration and productivity, lipid concentration and productivity of Ankistrodesmus sp. IFRPD 1061 (0.865 g/L, 76.250 mg/L/d, 0.167 g/L, and 14.685 mg/L/d, respectively) were found to be higher than those of Chlorella sp. IFRPD 1092 (0.433 g/L, 31.250 mg/L/d, 0.137 g/L, and 8.528 mg/L/d, respectively). Ankistrodesmus sp. IFRPD 1061 showed potential results of growing microalgae under photoautotrophic cultivation for biodiesel production.
The finance–growth nexus in the Middle East and Africa: A comparative meta‐analysis
Authors: Anwar Amar , Iwasaki Ichiro
Published: July 2022

By taking 1417 estimates from 96 studies and applying advanced meta‐analysis techniques, this study compares the effect size of financial development (FD) and liberalization on economic growth in the Middle East and Africa. We find that the overall finance–growth nexus is positive, yet its effect size differs across regions. Indeed, finance has a larger growth‐enhancing effect in the sub‐Saharan Africa (SSA) region than in the Middle East and North Africa region. This finding is supported by meta‐regression analysis that controls for various study conditions simultaneously. Moreover, we uncovered that the extracted estimates contain evidence of the true effect size of FD and liberalization on growth in the extant literature and SSA studies.
Knowledge about oral cancer among dental students and Primary Health Care dentists: A Brazilian study
Authors: de Lima Medeiros Yuri , de Matos Silveira Gabriela , Clemente Vitória Batista , Leite Isabel Cristina Gonçalves , Vilela Eduardo Machado , de Abreu Guimarães Letícia Drumond
Published: July 2022

Purpose/objectives

The present study aims to evaluate the knowledge of dental students and dentists who work in Primary Health Care (PHC). These are professionals who work in the public basic health units regarding oral cancer prevention, diagnosis, and treatment.

Methods

A cross‐sectional and observational Brazilian study was conducted. A survey with 27 questions was carried out regarding the (i) demographic, academic, and professional data of the participants, (ii) attitudes, practices, and self‐perception about their training, and (iii) knowledge about oral cancer. With the exception of one question regarding the clinical characteristics of oral cancer, all knowledge answers were graded as correct or incorrect. Grades were assigned to each participant according to their level of knowledge, and scores for each participant were calculated ranging from 1 to 10. Mann–Whitney and Kruskal–Wallis tests were used to examine the difference in the knowledge score of oral cancer according to explanatory variables. The level of significance adopted was 5%.

Results

The sample comprised 541 dental students and 82 PHC dentists. Most participants did not consider it appropriate or had not received training for palpation of lymph nodes or for identifying lymphadenopathies associated with oral cancer. Less than 20% of the participants had some kind of practice before and felt safe performing biopsy surgery. The average student score was 7.01 ± 2.15, and the average dentist score was 7.81 ± 1.467.

Conclusion

Although the scores were satisfactory, most of the participants did not show adequate knowledge about biopsy and palpation of cervical lymph nodes.
Non‐clinical considerations for supporting accelerated inclusion of pregnant women in pre‐licensure clinical trials with anti‐HIV agents
Authors: Greupink Rick , van Hove Hedwig , Mhlanga Felix , Theunissen Peter , Colbers Angela
Published: July 2022

Introduction

To allow the continued participation of women enrolled in pre‐licensure clinical trials who become pregnant, and to potentially enrol pregnant women in clinical trials, non‐clinical developmental and reproductive toxicology studies (DART) are essential. Generally during pharmaceutical development, DART studies are conducted late during clinical development, leading to the exclusion of pregnant women from enrolment and withdrawal of women becoming pregnant during pre‐licensure trials.

Discussion

Completing all DART studies prior to or early during the conduct of phase 3 trials (i.e. earlier than current common practice) can accelerate and facilitate the inclusion of women who become pregnant during pre‐licensure trials to remain on study drug and to potentially enrol pregnant women more rapidly. Promoting complementary strategies, such as alternative combinations of DART study designs and physiologically based pharmacokinetic modelling, could better inform drug dosing and safety in pregnancy at an earlier stage in drug development. The interpretation of the results of non‐clinical DART studies is often complex. Institutional review boards/ethics committees should have access to relevant expertise for interpretation and application of results of non‐clinical developmental and reproductive toxicity studies. Clear communication and thorough understanding of non‐clinical findings and the overall benefit–risk profile of the product are critical to review protocols and determine if women who become pregnant during a clinical trial could continue on study drug and/or to enrol pregnant women in the trial. The informed consent document should be well written so that participants can make an informed decision to stay on study drug or participate in a trial during pregnancy. Ultimately, the decision to allow women who become pregnant during pre‐licensure trials to remain on study will depend on the totality of the evidence and benefit–risk considerations.

Conclusions

We propose that industry completes non‐clinical reproductive toxicity studies prior to or early during the conduct of phase 3 trials in HIV drug development, especially for priority agents, and potentially uses alternative DART study design strategies to achieve this goal.
Development of optimized regression model for Raman spectral analysis of pharmaceutical drugs cefixime and sitagliptin
Authors: Bajwa Jawad‐ur‐Rehman , Hussain Abdullah Ijaz , Nawaz Haq , Chatha Shahzad Ali Shahid , Gulzar Tahsin
Published: July 2022

To build a robust model for the quantification of pharmaceutical drugs, different regression algorithms and preprocessing techniques are employed. In this study, Raman spectroscopy is used for the analysis of solid dosage formulations of two drugs, cefixime and sitagliptin. Using the different amounts of excipients and active pure ingredients (API), the different concentrations of cefixime and sitagliptin are made. The principal component regression (PCA), partial least‐squares regression (PLSR), and PLSR based on feature selection by variable importance in projection (VIP) scores are used to regress the model to quantify the API concentration of cefixime and sitagliptin in a mixture of excipients. These models are built on both normalized and unnormalized data of cefixime and sitagliptin to check the performance of the constructed models. By comparing errors of all trained models, it is observed that the root mean square error of calibration (RMSEC) and root mean square error of prediction (RMSEP) were minimum in the case of PLSR model construction on unnormalized data of both cefixime and sitagliptin.
State‐level scope of practice regulations for nurse practitioners impact work environments: Six state investigation
Authors: Poghosyan Lusine , Stein Jordan H. , Liu Jianfang , Spetz Joanne , Osakwe Zainab T. , Martsolf Grant
Published: July 2022

Nurse practitioner (NP) scope of practice (SOP) policies are different across the United States. Little is known about their impact on NP work environment in healthcare organizations. We investigated the association between SOP policies and organizational‐level work environment of NPs. Through a cross‐sectional survey design, data were collected from 1244 NPs in six states with variable SOP regulations (Arizona, New Jersey, Washington, Pennsylvania, Texas, and California) in 2018–2019. Arizona and Washington had full SOP—NPs had full authority to deliver care. New Jersey and Pennsylvania had reduced SOP with physician collaboration requirement; California and Texas had restricted SOP with physician supervision requirement. NPs completed mail or online surveys containing the Nurse Practitioner Primary Care Organizational Climate Questionnaire, which has these subscales: NP‐Administration Relations (NP‐AR), NP‐Physician Relations (NP‐PR), Independent Practice and Support (IPS), and Professional Visibility (PV). Regression models assessed the relationship between state‐level SOP and practice‐level NP work environment. NP‐AR scores were higher in full SOP states compared to reduced (β = 0.22,p < 0.01) and restricted (β = 0.15,p < 0.01) SOP states. Similarly, IPS scores were higher in full SOP states. The PV scores were also higher in full SOP states compared to reduced (β = 0.16,p < 0.001) and restricted (β = 0.12,p < 0.05) SOP states. There was no relationship between SOP and NP‐PR score. State‐level policies affect NP work environment. In states with more favorable policies, NPs have better relationships with administration and report more role visibility and support. Efforts should be made to remove unnecessary SOP restrictions.
ADOPO‐anchored benzothiadiazole derivative toward efficiently P/N/S synergistic flame retarding of epoxy thermoset
Authors: Zhang Wu , Xia Weikang , Shi Yasheng , Zhou Changlin , Chen Ran , Wang Lei , Qu Jinqing
Published: July 2022

Flame‐retarded epoxy thermosets are highly desirable for electronics‐related basic materials in the new‐generation information applications. Herein, a DOPO‐anchored benzothiadiazole flame retardant, namelyDOPO‐BTD, is designed and synthesized for P/N/S synergistic flame‐retarded epoxy thermosets.DOPO‐BTDpossesses good thermal stability and excellent compatibility with the epoxy matrix. As reflected by UL 94 test, theDOPO‐BTDcoated EP passes the V0 rating and achieves a higher LOI value of 34.6% at ultralow P content of 0.39 wt%. The investigation of theDOPO‐BTD‐triggered P/N/S synergistic flame‐retarded effect by thermal images further validated the flame retarded efficacy and dramatic inhibition of the flame. Meanwhile, the incorporation of 4.8 wt%DOPO‐BTDinto the epoxy matrix, the PHRR, THR, SPR, TSP, and COP are significantly decreased by 37.97%, 27.44%, 25.49%, 19.83%, and 31.70%, respectively. Additionally, the fire growth index (FGI) is sharply dropped 26.06%. Moreover, the TGIR and TGMS results convince the flame‐retarded mechanism ofDOPO‐BTDthrough the combination of the gas‐phase and condensed‐phase pathways. The P/N/S synergisticDOPO‐BTDcan serve as a promising flame retardant for efficiently fabricating the flame‐retarded epoxy thermosets, and this study sheds light on the development of multiple elements synergistic flame‐retardants for functional polymers with great application potential.
Aqueous solution blending route for preparing flexible and antistatic polyimide/carbon nanotube composite films with core‐shell structured polyimide/graphene microspheres
Authors: Jiang Hanzhou , Xu Lubo , Chen Guofei , Fang Xingzhong
Published: July 2022

To explore the process of preparing polyimide (PI) microspheres with specific particle size, the effects such as the ratio of surfactant to PI, concentration of PI, stirring speed, and temperature on the particle size and distribution of PI microspheres were investigated in detail. The core‐shell structured PI@reduced graphene oxide (rGO) microspheres were prepared by reduction of PI microspheres with an average particle size of 1.11 μm coated with GO. The PI/carbon nanotube (CNT) composites films were fabricated with poly(amic acid) ammonium salts (PAAS) aqueous solution blending route. A three‐dimensional (3D) conductive network was constructed due to the CNTs were connected by microspheres and arranged in a random orientation. Thus, The PI/CNT composite films exhibited well antistatic properties and volume resistivity dropped by five orders of magnitude to 6.56 × 105 Ω·cm after adding 15 phr PI@rGO microspheres. Moreover, the composite films still have good mechanical properties and excellent thermal properties.
Post‐glacial dynamics of an alpine Little Ice Age glacitectonized frozen landform (Aget, western Swiss Alps)
Authors: Wee Julie , Delaloye Reynald
Published: July 2022

Glaciers and frozen‐debris landforms have coexisted and episodically or continuously interacted throughout the Holocene at elevations where the climate conditions are cold enough for permafrost to occur. In the European Alps, the Little Ice Age (LIA) characterized the apogee of the last interaction phase. In areas of consecutive post‐LIA glacier shrinkage, the geomorphological dominant conditioning of the ongoing paraglacial phase may have transitioned from glacial to periglacial and later even shifted to post‐periglacial. Such transitions can be observed through the morphodynamics of glacitectonized frozen landforms (GFLs), which are permafrost‐related pre‐existing frozen masses of debris deformed (tectonized) by the pressure exerted by an interacting glacier. This contribution aims at evidencing the processes driving the ongoing morphodynamical evolution of an actively back‐creeping GFL within the LIA forefield of the Aget glacier on the basis of long‐term time series of ground surface temperature, and in‐situ geodetic and geoelectrical measurements. Our observations for the last two decades (1998–2020), which have been the warmest since the LIA, reveal a resistivity decrease in the permafrost body and a surface subsidence of up to a few centimeters per year. The former indicate a liquid water‐to‐ice content ratio increase within the permafrost body and the latter a ground ice melt at the permafrost table, both processes having taken place heterogeneously at the scale of the landform. The absence of acceleration of landform motion during that period despite a probable warming trend of the frozen ground may indicate that the ongoing degradation is reaching a tipping point at which processes related to interparticle friction and thinning of the permafrost body contribute to gradually inactivate the mechanism of permafrost creep.
Characteristics and outcome of infants with bronchopulmonary dysplasia established on long‐term ventilation from neonatal intensive care
Authors: Ong Jonathan Wen Yi , Everitt Lucy , Hiscutt Jodie , Griffiths Catherine , McEvoy Alison , Goss Kevin Colin William , Johnson Mark John , Evans Hazel J.
Published: July 2022

Introduction

Ex‐preterm infants with severe bronchopulmonary dysplasia (BPD) sometimes require long‐term ventilation (LTV) to facilitate weaning from respiratory support. There are however limited data characterizing this cohort. We aim to describe the background characteristics, neonatal comorbidities, characteristics at the initiation of ventilation, and outcomes of neonatal unit graduates with BPD established on LTV.

Methods

A retrospective cohort study of infants born <32 weeks gestation with BPD referred to a regional LTV service between January 2015 and December 2020.

Results

Twenty‐five infants were referred during the study period. Median birth gestation was 26 + 1 weeks (24 + 0–30 + 4) and birth weight 645 g (430–1485). At 36 weeks postmenstrual age (PMA), median FiO2 was 0.45 (0.24–0.80) and one‐quarter of infants remained on invasive ventilation. Twenty (80%) infants were established on noninvasive ventilation (NIV), with the smallest weighing 2085 g, and five (20%) required tracheostomy invasive ventilation (TIV). At initiation of NIV/TIV, median PMA was 41 + 1 weeks and median FiO2 0.40 (0.29–0.80). Infants established on TIV spent almost five times longer in hospital before discharge compared to those on NIV (p = 0.003). By March 2022, 18 (72%) infants had discontinued ventilation, spending a median total time of 113 days (18–1792) on ventilation.

Conclusion

Due to advances in interfaces, headgear, and ventilator technology, NIV is an attractive and practically achievable option for infants with severe BPD as small as 2 kg. Initiation and weaning should take place in a facility with the required multidisciplinary expertize.
Detonation Characteristics of an Aluminized DNAN‐Based Melt‐Cast Explosive
Authors: Yang Yang , Duan Zhuoping , Li Shurui , Han Yong , Huang Hui , Zhang Liansheng , Huang Fenglei
Published: July 2022

Investigations of the detonation characteristics of a new aluminized DNAN‐based melt‐cast explosive RMA‐2X (containing 30 wt.% DNAN (2,4‐dinitroanisole), 30 wt.% NTO (3‐nitro‐1,2,4‐triazol‐5‐one), 10 wt.% HMX (1,3,5,7‐tetranitro‐1,3,5,7‐tetraazacyclooctane) and 30 wt.% aluminum) were undertaken, as well as a lithium fluoride (LiF) substituted explosive RMF‐2X (containing 30 wt.% DNAN, 30 wt.% NTO, 10 wt.% HMX and 30 wt.% LiF). The interfacial velocity experiment was carried out to measure the reaction zone parameters (including the CJ pressure, the pressure at the Von Neumann spike, and the reaction zone length) of RMA‐2X. The cylinder test was also performed, and employing the test data, the detonation velocity, the Gurney energy, and the detonation energy of RMA‐2X were calculated. Investigation results are analyzed and some conclusions are drawn. The role of aluminum in the detonation characteristics are also discussed. Finally, parameters of the Jones‐Wilkins‐Lee equation of state of the detonation products were confirmed.
Micromechanical Behavior of HTPB Propellant Bonding Interface under Uniaxial Tensile Loading
Authors: Pei Shu‐di , Qiang Hong‐fu , Wang Xue‐ren , Wang Jia‐xiang , Li Shi‐qi
Published: July 2022

In order to study the mechanical behavior of solid rocket motor charge bonding interface under uniaxial tensile loading, the bonding interface of HTPB propellant/liner/insulator during uniaxial tensile process was scanned and reconstructed based on micro‐CT in‐situ loading, and the variation of porosity and interface debonding rate with strain was analyzed. A damage‐containing constitutive model based on the evolution of meso‐characteristic parameters was established for bonded interfacial components. The experimental analysis shows that the initial defects have a great influence on the location and evolution direction of the interface damage, and the interface damage can be quantitatively characterized by the interface debonding rate and porosity, and the interface debonding rate can better reflect the damage evolution process of micro‐pores and cracks near the propellant/liner interface. The damage‐containing constitutive model based on the evolution of mesoscopic characteristic parameters can effectively establish the structure‐activity relationship between mesoscopic parameters and macroscopic mechanical properties, and can predict the mechanical behavior of charge interface.
Efficient and relevant stepwise covariate model building for pharmacometrics
Authors: Svensson Robin J. , Jonsson E. Niclas
Published: July 2022

Covariate modeling is an important opportunity for pharmacometrics to influence decision making in drug development. The stepwise covariate model (SCM) building procedure is the most common method for covariate model development. Despite its advantages, the traditional SCM method is known to have long runtimes and the suboptimal ability to select relevant covariates, especially in more complex phase III settings. In this work, two alternative approaches are presented: SCM+, which introduces the “adaptive scope reduction” and changes to general estimation settings, and “stage‐wise filtering,” which groups covariates into categories based on their importance (mechanistic, structural, and exploratory). The three methods (SCM, SCM+, and SCM+ with stage‐wise filtering) are applied to data from a simulated phase III population pharmacokinetic study and are compared in terms of efficiency and relevance. The two SCM+ methods were considerably more efficient than the traditional SCM: the number of function evaluations was reduced by 70% for SCM+ and by 76% for SCM+ with stage‐wise filtering compared to SCM; the corresponding number of executed models was reduced by 44% for SCM+ and 70% for SCM+ with stage‐wise filtering. In addition, among the three methods, SCM+ with stage‐wise filtering selected the highest number of relevant covariates. Given the improved efficiency and ability to select relevant covariates shown in this work, the use of SCM+ and stage‐wise filtering can greatly increase the efficiency of covariate modeling in drug development, which will ultimately facilitate more timely support for decision making.
Grain Boundary Engineering Enabled High‐Performance Garnet‐Type Electrolyte for Lithium Dendrite Free Lithium Metal Batteries
Authors: Zheng Chujun , Lu Yan , Su Jianmeng , Song Zhen , Xiu Tongping , Jin Jun , Badding Michael E. , Wen Zhaoyin
Published: July 2022

Solid‐state lithium metal batteries (SSLMBs) are attracting increasing attentions as one of the promising next‐generation technologies due to their high‐safety and high‐energy density. Their practical application, however, is hindered by lithium dendrite growth and propagation in solid‐state electrolytes (SSEs). Herein, an in situ grain boundary modification strategy relying on the reaction between Li2TiO3 (LTO) and Ta‐substituted garnet‐type electrolyte (LLZT) is developed, which forms LaTiO3 along with lesser amounts of LTO/Li2ZrO3 at the grain boundaries (GBs). The second phases of LTO/Li2ZrO3 inhibit abnormal grain growth. The presence of LaTiO3 at the GBs reduces electronic conductivity and improves mechanical strength, which can hinder dendrite formation and block lithium dendrite penetration through the LLZT. Moreover, the adjacent grains by LaTiO3 build a continuous Li+ transport path, providing a homogeneous Li+ flux throughout the whole LLZT‐4LTO. As a result, symmetric cells of Li | LLZT‐4LTO | Li shows a high critical current density of 1.8 mA cm−2 and a long cycling stability up to 2000 h at 0.3 mA cm−2. Moreover, the high‐voltage full cells demonstrate remarkable cycling stability and rate performance. It is believed that this novel grain boundary modification strategy can shed light on the constructing of high‐performance SSEs for practical SSLMBs.
Risk‐based approach for managing obsolescence for automation systems in heavy industries
Authors: Ault Trevor , Bradley Thomas
Published: July 2022

Obsolescence is an important consideration in the management and engineering of heavy industrial facilities. Examples of these could include refineries, chemical plants, and other large‐scale materials processing facilities. These facilities have lifetimes of many decades but operate on software, automation hardware, and other electrical equipment that reaches obsolescence much sooner than the rotating equipment, unit operations, and other major systems of the facility. This work proposes a method to manage obsolescence of automation and electrical systems at industrial sites. This risk management method was developed by first analyzing a database of upgrade projects at several industrial sites and identifying parts that had been replaced due to obsolescence. The analysis was used to prioritize replacement of obsolescent parts based on the average operational lifespans, their criticality in operations, their manufacturer's continued production state, and other factors. Based on those results, a taxonomy of obsolescence risk, and a risk assessment plan were developed to manage the replacement of parts. The value of this proposed management strategy was validated through its application to 13 heavy industrial facilities. The results indicate a reduction of roughly 70% in reactive replacements due to obsolescence after the major upgrade and a 24% reduction in unplanned downtime due to part failure during normal operations. While this study is focused on heavy industries, the proposed method for identifying and managing component obsolescence can be applied to other industries and systems.
Diagnosis and management of primary liver cancer in men
Authors: Raptis Dimitri , Imber Charles
Published: July 2022

A number of options are available to treat liver cancer, from non‐invasive techniques to surgery. However, as with so many diseases, prevention is the best approach: identification of high‐risk groups and behaviours plays a key role along with strategies to mitigate risk.
Journal watch
Authors: Kirby Mike
Published: July 2022

Professor Mike Kirby, Editor of Trends in Urology and Men's Health, picks some interesting recent papers and highlights the ‘take‐home’ messages.
Keeping development on time: Insights into post‐transcriptional mechanisms driving oscillatory gene expression during vertebrate segmentation
Authors: Blatnik Monica C. , Gallagher Thomas L. , Amacher Sharon L.
Published: July 2022

Biological time keeping, or the duration and tempo at which biological processes occur, is a phenomenon that drives dynamic molecular and morphological changes that manifest throughout many facets of life. In some cases, the molecular mechanisms regulating the timing of biological transitions are driven by genetic oscillations, or periodic increases and decreases in expression of genes described collectively as a “molecular clock.” In vertebrate animals, molecular clocks play a crucial role in fundamental patterning and cell differentiation processes throughout development. For example, during early vertebrate embryogenesis, the segmentation clock regulates the patterning of the embryonic mesoderm into segmented blocks of tissue called somites, which later give rise to axial skeletal muscle and vertebrae. Segmentation clock oscillations are characterized by rapid cycles of mRNA and protein expression. For segmentation clock oscillations to persist, the transcript and protein molecules of clock genes must be short‐lived. Faithful, rhythmic, genetic oscillations are sustained by precise regulation at many levels, including post‐transcriptional regulation, and such mechanisms are essential for proper vertebrate development.

This article is categorized under:

RNA Export and Localization > RNA Localization

RNA Turnover and Surveillance > Regulation of RNA Stability

Translation > Regulation
D-instanton induced superpotential
Authors: Alexandrov Sergei , Fırat Atakan Hilmi , Kim Manki , Sen Ashoke , Stefański Bogdan
Published: July 2022

Abstract

We use string field theory to fix the normalization of the D-instanton corrections to the superpotential involving the moduli fields of type II string theory compactified on an orientifold of a Calabi-Yau threefold in the absence of fluxes. We focus on O(1) instantons whose only zero modes are the four bosonic modes associated with translation of the instanton in non-compact directions and a pair of fermionic zero modes associated with the two supercharges broken by the instanton. We work with a generic superconformal field theory and express our answer in terms of the spectrum of open strings on the instanton. We analyse the contribution of multi-instantons of this kind to the superpotential and argue that it vanishes when background fluxes are absent.
Adaptive discretization-based algorithms for semi-infinite programs with unbounded variables
Authors: Jungen Daniel , Djelassi Hatim , Mitsos Alexander
Published: July 2022

The proof of convergence of adaptive discretization-based algorithms for semi-infinite programs (SIPs) usually relies on compact host sets for the upper- and lower-level variables. This assumption is violated in some applications, and we show that indeed convergence problems can arise when discretization-based algorithms are applied to SIPs with unbounded variables. To mitigate these convergence problems, we first examine the underlying assumptions of adaptive discretization-based algorithms. We do this paradigmatically using the lower-bounding procedure of Mitsos [Optimization 60(10–11):1291–1308, 2011], which uses the algorithm proposed by Blankenship and Falk [J Optim Theory Appl 19(2):261–281, 1976]. It is noteworthy that the considered procedure and assumptions are essentially the same in the broad class of adaptive discretization-based algorithms. We give sharper, slightly relaxed, assumptions with which we achieve the same convergence guarantees. We show that the convergence guarantees also hold for certain SIPs with unbounded variables based on these sharpened assumptions. However, these sharpened assumptions may be difficult to prove a priori. For these cases, we propose additional, stricter, assumptions which might be easier to prove and which imply the sharpened assumptions. Using these additional assumptions, we present numerical case studies with unbounded variables. Finally, we review which applications are tractable with the proposed additional assumptions.
Free vascularized flap reconstruction for osteoradionecrosis of the mandible: a 25-year retrospective cohort study
Authors: van den Heuvel Stefanie C. M. , van den Dungen T. R. I. , Schulten E. A. J. M. , Mullender M. G. , Winters H. A. H.
Published: July 2022

Background

Osteoradionecrosis of the jaw is a severe complication of radiotherapy in head and neck cancer patients.If conservative treatment and surgical debridement have been unsuccessful, the preferred treatment for symptomatic mandibular osteoradionecrosis (mORN) is radical surgery and subsequent reconstruction with a free vascularized flap. This study aims to assess the outcomes of free vascularized flap reconstruction in mORN.

Methods

A retrospective study was conducted on all patients who underwent a free vascularized flap reconstruction for mORN between 1995 and 2021 in Amsterdam UMC – VUmc, The Netherlands.

Results

In our cohort study, three of the twenty-eight flap reconstructions failed (10.7%). No recurrences of mORN were observed during a mean follow-up of 8 years.

Conclusions

The success rate of free vascularized flap reconstruction for mORN is high. The fibula is the preferred free flap for mandibular reconstruction in mORN cases. However, this type of surgery is at risk for complications and patients need to be informed that these complications may require surgical re-intervention.

Level of evidence: Level IV, Therapeutic; Risk/Prognostic.
Risk and cause of death in post-traumatic epilepsy: a register-based retrospective cohort study
Authors: Karlander Markus , Ljungqvist Johan , Sörbo Ann , Zelano Johan
Published: July 2022

Objective

Post-traumatic epilepsy (PTE) is common, but its impact on survival after traumatic brain injury (TBI) of different severity and in different demographic patient groups is unknown. We analyzed the risk of death associated with PTE with adjustment for TBI severity, causes of death, and the contribution of epilepsy as direct or contributing cause of death.

Methods

Register-based, retrospective cohort study. All individuals hospitalized in Sweden for a TBI between 2000 and 2010 without prior seizures were identified in the National Patient Register, with follow-up until 2017. Subsequent epilepsy was identified by ICD-10 codes. Time-dependent Cox proportional hazard ratio (HR) was used to assess hazard of death, with epilepsy as a time-updated covariate. Adjusted analyses for age, gender, injury severity and comorbidities were also performed. Causes of death were analyzed using the Cause of Death Register.

Results

Among 111 947 individuals with TBI, subsequent epilepsy diagnosis was associated with a crude HR of 2.3 (95% CI: 2.2–2.4) for death. Stratified analyses showed a HR of 7.8 (95% CI: 6.5–9.4) for death in younger individuals. Epilepsy was a more common underlying cause of death in younger individuals.

Conclusion

PTE is associated with a higher risk of death and epilepsy seems to contribute to a significant proportion of deaths, especially in younger age groups. Future studies on whether improved epilepsy treatment can reduce mortality are needed.
Pathological processing of sentinel lymph nodes in endometrial carcinoma — routine aspects of grossing, ultra-staging, and surgico-pathological parameters in a series of 833 lymph nodes
Authors: Rau Tilman T. , Deppeler Mona V. , Christe Lucine , Siegenthaler Franziska , Imboden Sara , Papadia Andrea , Mueller Michael D.
Published: July 2022

Sentinel lymph nodes are widely accepted in the treatment of endometrial carcinoma. Whereas surgical aspects are well studied, the pathological work-up in terms of grossing, frozen section, and the so-called ultra-staging is still a matter of debate. This results in conflicting national or center-based recommendations. In a series of consecutive 833 sentinel lymph nodes from 206 patients in endometrial carcinomas, we compared three different grossing techniques and the use of frozen section in terms of anatomy, detection rates, and survival. In total, 42 macro-metastases, 6 micro-metastases, and 25 nodes with isolated tumor cells were found. Lymph nodes affected at least with micro-metastasis were about 0.5cm enlarged. Detection rates in lamellation technique increased with a step of 5.9% to 8.3% in comparison to bi-valved or complete embedding. The lamellation technique presented with a slight beneficial prognosis in pN0 subgroup (OS, p=0.05), which besides size effects might be attributed to trimming loss. In frozen section, this effect was less pronounced than expected (OS, p=0.56). Ultra-staging only revealed additional micro-metastases and isolated tumor cells. Exclusively, macro-metastases showed poor survival (p<0.001). In multivariate analysis, T-stage, subtype, and lympho-vascular invasion status outperformed this staging parameter significantly. Grossing of sentinel lymph nodes is the most essential step with evidence to prefer lamellation in 2 mm steps. Step sectioning should consider widely spaced protocols to exclude macro-metastases. Frozen sections might add value to the intra-operative assessment of endometrial carcinoma in selected cases. The excellent biological behavior of cases with isolated tumor cells might question the routine application of pan-cytokeratin as ultra-staging method.
Surgery for degenerative cervical myelopathy in the elderly: a nationwide registry-based observational study with patient-reported outcomes
Authors: Johansen Tonje Okkenhaug , Vangen-Lønne Vetle , Holmberg Siril T. , Salvesen Øyvind O. , Solberg Tore K. , Gulati Agnete M. , Nygaard Øystein P. , Gulati Sasha
Published: July 2022

Background

The aim of this study was to investigate whether clinical outcomes in patients aged ≥ 70 undergoing decompressive surgery for degenerative cervical myelopathy (DCM) differ from those of younger patients (50–70 years) at 1 year.

Methods

Data were obtained from the Norwegian Registry for Spine Surgery (NORspine). Among 651 patients included, 177 (27.2%) were ≥ 70 years old. The primary outcome was change in the Neck Disability Index (NDI). Secondary outcomes were changes in the European Myelopathy Score (EMS), quality of life (EuroQoL EQ-5D), numeric rating scales (NRS) for headache, neck pain, and arm pain, and complications.

Results

Significant improvements in all patient-reported outcomes (PROMs) were detected for both age cohorts at 1 year. For the two age cohorts combined, there was a statistically significant improvement in the NDI score (mean 9.2, 95% CI 7.7 to 10.6, P < 0.001). There were no differences between age cohorts in mean change of NDI (− 8.9 vs. − 10.1, P = 0.48), EQ-5D (0.13 vs. 0.17, P = 0.37), or NRS pain scores, but elderly patients experienced a larger improvement in EMS (0.7 vs. 1.3, P = 0.02). A total of 74 patients (15.6%) in the younger cohort and 43 patients (24.3%) in the older cohort experienced complications or adverse effects within 3 months of surgery, mainly urinary and respiratory tract infections.

Conclusion

Surgery for DCM was associated with significant improvement across a wide range of PROMs for both younger and elderly patients. Surgery for DCM should not be denied based on age alone.
Classification of Mammographic ROI for Microcalcification Detection Using Multifractal Approach
Authors: Kermouni Serradj Nadia , Messadi Mahammed , Lazzouni Sihem
Published: July 2022

Microcalcifications (MCs) are the main signs of precancerous cells. The development of aided-system for their detection has become a challenge for researchers in this field. In this paper, we propose a system for MCs detection based on the multifractal approach that classifies mammographic ROIs into normal (healthy) or abnormal ROIs containing MCs. The proposed method is divided into four main steps: a mammogram pre-processing step based on breast selection, breast density reduction using haze removal algorithm and contrast enhancement using multifractal measures. The second step consists of extracting the normal and abnormal ROIs and calculating the multifractal spectrum of each ROI. The next step represents the extraction of the multifractal features from the multifractal spectrum and the GLCM characteristics of each ROI. The last step is the classification of ROIs where three classifiers are tested (KNN, DT, and SVM). The system is evaluated on images from the INbreast database (308 images) with a total of 2688 extracted ROIs (1344 normal, 1344 with MC) from different BI-RADS classes. In this study, the SVM classifier gave the best classification results with a sensitivity, specificity, and precision of 98.66%, 97.77%, and 98.20% respectively. These results are very satisfactory and remarkable compared to the literature.