bluuebunny/crossref_metadata_2025 huggingface dataset:
Stress‐induced Rab11a‐exosomes induce amphiregulin‐mediated cetuximab resistance in colorectal cancer
Authors: Mason John D. , Marks Ewan , Fan Shih‐Jung , McCormick Kristie , Wilson Clive , Harris Adrian L. , Hamdy Freddie C. , Cunningham Chris , Goberdhan Deborah C. I.
Published: June 2024

Exosomes are secreted vesicles made intracellularly in the endosomal system. We have previously shown that exosomes are not only made in late endosomes, but also in recycling endosomes marked by the monomeric G‐protein Rab11a. These vesicles, termed Rab11a‐exosomes, are preferentially secreted under nutrient stress from several cancer cell types, including HCT116 colorectal cancer (CRC) cells. HCT116 Rab11a‐exosomes have particularly potent signalling activities, some mediated by the epidermal growth factor receptor (EGFR) ligand, amphiregulin (AREG). Mutant activating forms of KRAS, a downstream target of EGFR, are often found in advanced CRC. When absent, monoclonal antibodies, such as cetuximab, which target the EGFR and block the effects of EGFR ligands, such as AREG, can be administered. Patients, however, inevitably develop resistance to cetuximab, either by acquiring KRAS mutations or via non‐genetic microenvironmental changes. Here we show that nutrient stress in several CRC cell lines causes the release of AREG‐carrying Rab11a‐exosomes. We demonstrate that while soluble AREG has no effect, much lower levels of AREG bound to Rab11a‐exosomes from cetuximab‐resistant KRAS‐mutant HCT116 cells, can suppress the effects of cetuximab on KRAS‐wild type Caco‐2 CRC cells. Using neutralising anti‐AREG antibodies and an intracellular EGFR kinase inhibitor, we show that this effect is mediated via AREG activation of EGFR, and not transfer of activated KRAS. Therefore, presentation of AREG on Rab11a‐exosomes affects its ability to compete with cetuximab. We propose that this Rab11a‐exosome‐mediated mechanism contributes to the establishment of resistance in cetuximab‐sensitive cells and may explain why in cetuximab‐resistant tumours only some cells carry mutant KRAS.
Does a subset of mature T‐cell leukemias with features akin to T‐cell prolymphocytic leukemia but lacking rearrangement of the TCL1 represent peripheral T‐cell lymphoma, NOS in a leukemic phase?
Authors: Gajzer David C. , Chen Xueyan , Sabath Daniel E. , Poh Christina , Naresh Kikkeri N.
Published: June 2024

In the current WHO classification, a T‐cell prolymphocytic leukemia (T‐PLL) diagnosis requires lymphocytosis of >5 × 109/L, evidence of monoclonality, and TCL1A or MTCP1 rearrangement. However, the 2019 consensus document suggested that in the absence of rearrangement of TCL1‐family, the presence of abnormalities involving chromosome 11 (11q22.3; ATM), chromosome 8 (idic(8)(p11), t(8;8), trisomy 8q), 5, 12, 13, 22, or a complex karyotype, as well as involvement specific sites (e.g., splenomegaly, effusions) would suffice for a diagnosis of T‐PLL. We present a patient diagnosed with T‐PLL with MTCP1 rearrangement who was successfully treated with alemtuzumab followed by consolidative allogeneic unrelated donor stem cell transplantation. Eight years later, the patient presented with inguinal lymphadenopathy with features more akin to peripheral T‐cell lymphoma, NOS (PTCL, NOS) of the GATA3 subtype, and there was no evidence of peripheral blood involvement. However, the lymphoma cells were clonally related to those at presentation. Currently, literature on T‐PLL‐like cases lacking the rearrangement of TCL1A is limited, and the possibility of whether a proportion of such cases could represent PTCL, NOS (with leukemic involvement) needs consideration.
Renal screening sonography—A comparative study in a Portuguese basic emergency service
Authors: Miravent Sérgio , Jiménez Carmen , Barbancho Narciso , Lobo Manuel Duarte , Figueiredo Teresa , Gomes Carla , Ratusneac Ion , Gonçalves João Mário , Hasnas Corina , de Almeida Rui
Published: June 2024

Introduction

This study intends to compare the accuracy and pertinence of sonographic findings obtained by a sonographer in a Basic Emergency Service (BES) with the imaging findings at the Referral Hospital (RH).

Methods

Thirty‐one patients suspected of having renal pathology underwent initial renal sonography screening with sonographer reporting at the BES and were subsequently referred to the RH for additional imaging examinations. The results of both examinations were compared to verify whether the findings from the BES were confirmed by the radiologist in the RH and to ensure that the patient referrals from BES to RH were appropriate.

Results

In our sample, most patients (80%) exhibited varying degrees of pyelocaliceal distension, with nearly half (48%) presenting obstructions. A strong association between the sonographic findings in the BES and the RH was found in the variables “Dilatation of pyelocaliceal system” (V=0.895; p=0.000), “Simple cystic formation” (V=0.878; p=0.000), respectively. There was a statistically significant correlation between BES and RH findings, indicating a strong association between these two variables respectively (k=0.890; p=0.000) and (k=0.870; p=0.000). In this research, an achieved sensitivity of 96% and a specificity of 85% were demonstrated in the identification of pyelocaliceal dilatation.

Conclusion

Renal sonographer reporting screening successfully detected abnormalities in the urinary system of patients suspected of having renal colic. The sonographic data obtained at the BES demonstrated a strong correlation with the additional imaging findings from the RH in Portugal. These results suggest that Radiographers/Sonographers can have an important role in the preliminary assessment of urgent renal pathology in remote areas, contributing to a correct referral and early treatment.
Are There Hidden Adverse Events in Hypoglossal Nerve Stimulation: Comparing Social Media and a Federal Database
Authors: Bentan Mihai A. , Dawood Emaan , Moffatt David , Suurna Maria V. , Nord Ryan
Published: June 2024

Objective

Hypoglossal nerve stimulation (HNS) can be an effective treatment for moderate to severe obstructive sleep apnea (OSA) in positive airway pressure (PAP) intolerant patients. To better understand patient experiences with HNS therapy, we explored reported events from HNS‐related Facebook groups and the Manufacturer and User Facility Device Experience (MAUDE) database.

Methods

A retrospective analysis of HNS‐related Facebook posts from three groups pertaining to HNS therapy, from October 1, 2022 to October 1, 2023, was performed. Posts were analyzed for patient‐reported adverse events. Concurrently, the MAUDE database was reviewed for HNS‐related events during the same timeframe.

Results

From 737 Facebook posts, 132 (17.55%) adverse events were identified. Adverse events included pain (34.85%), stimulation discomfort (14.39%), lip weakness (6.82%) and issues related to lead tethering or tight leads around the neck (3.79%). Analysis of the MAUDE database found 428 adverse events, including pain (24.07%), lip weakness (0.44%), and lead tethering (1.64%).

Conclusion

Facebook group members reported higher rates of lip weakness and lead tethering than recorded in the MAUDE database. These findings illustrate how diverse data sources, such as social media, can enhance our understanding of patient experiences and identify gaps in patient education with HNS therapy.

Level of Evidence

NA Laryngoscope, 134:5217–5222, 2024
Ultrawide Dynamic Sensing from Single‐Photon Counting to Linear Detection Using a Segmented Superconducting Nanowire
Authors: Ru Sai‐Ying , Hao Hao , Zhao Qing‐Yuan , Li Zhi‐Jian , Liu Hao , Liu Zhen , Deng Jie , Huang Yang‐Hui , Yang Fan , Liu Nai‐Tao , Wan Chao , Tu Xue‐Cou , Zhang La‐Bao , Jia Xiao‐Qing , Chen Jian , Kang Lin , Wu Pei‐Heng
Published: June 2024

Despite their exceptional sensitivity, single photon detectors typically exhibit limited tolerance to strong light compared to conventional linear photodetectors. Consequently, a disparity arises between these two detector types, hindering the achievement of both high sensitivity and high dynamic range in sensing and imaging. To bridge this gap, a segmented architecture is implemented with a waveform‐variance readout scheme for extacting high‐flux photon informaiton.This approach gives an unprecedented ultra‐high dynamic range of 75 dB at a fixed bias current, where single photon counting mode and quasi‐linear photodetection mode coexist. High‐dynamic imaging, passive thermal imaging, and joint active and passive imaging are demonstrated, which validate the advantages of this dual‐mode detector. Such a versatile detector will offer enhanced flexibility, single‐photon sensitivity, as well as ultra‐wide dynamic range across various scientific and technical domains.
An extended stochastic car‐following model and its feedback control
Authors: Liu Zhonghua , Kong Qinghu
Published: June 2024

Real‐world traffic flow is influenced by various random factors. Gaussian white noise is employed to describe the inherent randomness of traffic flow. A stochastic optimization velocity model is established for dynamic analysis. To enhance the traffic flow stability, the velocity difference of two successive vehicles ahead is considered. The velocity difference feedback control strategy is proposed, utilizing the velocity differences between the vehicle and the two targeted vehicles as control signals. Stability conditions for both the stochastic optimization velocity model and the feedback control model are derived by using the moment stability theory. The study demonstrates that the random factors can destabilize traffic flow, while the proposed feedback control strategy effectively stabilizes traffic flow. Additionally, the influences of random factors on the stability of traffic flow are discussed extensively, aiding in understanding actual traffic congestion mechanisms and offering insights for traffic control strategies.
Analysis of finite Haar wavelet transform and its implementation
Authors: Poumai Khole Timothy , Khanna Nikhil , Kaushik S. K.
Published: June 2024

In this paper, we give frame‐based finite Haar wavelet transform of
‐scale and
‐level (FHWT(
). The formulation of FHWT
is based on the finite nonuniform wavelet transform (FNUWT), and the reconstruction is done using
‐frame reconstruction property. We formulate the FNUWT based on the technique of nonuniform sampling and study the reconstruction property of FNUWT in terms of the
‐frame reconstruction property. FHWT
is a particular model of FNUWT based on critical sampling. Using the principles of
‐frame, we prove that FHWT(
is a unitary operator. Also, our formulation enables us to define the finite Haar wavelet basis (FHWB) explicitly. In our study, we establish another variant of the fast Haar wavelet transform with varying rate of sampling, and with fast computations. Finally, we formulate the algorithms of finite Haar wavelet transform and its inverse through block implementations of
‐frame. It is observed that the number of computations involved in FHWT(
) is far less than the number of computations required in the fast Fourier transform.
Accelerated B1+$$ {\mathrm{B}}_1^{+} $$ mapping and robust parallel transmit pulse design for heart and prostate imaging at 7 T
Authors: Egger Nico , Nagelstraßer Sophia , Wildenberg Saskia , Bitz Andreas , Ruck Laurent , Herrler Jürgen , Meixner Christian Rainer , Kimmlingen Ralph , Lanz Titus , Schmitter Sebastian , Uder Michael , Nagel Armin Michael
Published: June 2024

Purpose

To investigate the impact of reduced k‐space sampling on mapping and the resulting impact on phase shimming and dynamic/universal parallel transmit (pTx) RF pulse design.

Methods

Channel‐wise 3D maps were measured at 7 T in 35 and 23 healthy subjects for the heart and prostate region, respectively. With these maps, universal phase shims optimizing homogeneity and efficiency were designed for heart and prostate imaging. In addition, universal 4kT‐point pulses were designed for the heart. Subsequently, individual phase shims and individual 4kT‐pulses were designed based on maps with different acceleration factors and tested on the original maps. The performance of the pulses was compared by evaluating their coefficients of variation (CoV), efficiencies and specific energy doses (SED). Furthermore, validation measurements were carried out for one heart and one prostate subject.

Results

For both organs, the universal phase shims showed significantly higher efficiencies and lower CoVs compared to the vendor provided default shim, but could still be improved with individual phase shims based on accelerated maps (acquisition time = 30 s). In the heart, the universal 4kT‐pulse achieved significantly lower CoVs than tailored phase shims. Tailored 4kT‐pulses based on accelerated maps resulted in even further reduced CoVs or a 2.5‐fold reduction in SED at the same CoVs as the universal 4kT‐pulse.

Conclusion

Accelerated maps can be used for the design of tailored pTx pulses for prostate and cardiac imaging at 7 T, which further improve homogeneity, efficiency, or SED compared to universal pulses.
Fat suppression using frequency‐sweep RF saturation and iterative reconstruction
Authors: Zi Ruoxun , Benkert Thomas , Chandarana Hersh , Lattanzi Riccardo , Block Kai Tobias
Published: June 2024

Purpose

To introduce an alternative idea for fat suppression that is suited both for low‐field applications where conventional fat‐suppression approaches become ineffective due to narrow spectral separation and for applications with strong B0 homogeneities.

Methods

Separation of fat and water is achieved by sweeping the frequency of RF saturation pulses during continuous radial acquisition and calculating frequency‐resolved images using regularized iterative reconstruction. Voxel‐wise signal‐response curves are extracted that reflect tissue's response to RF saturation at different frequencies and allow the classification into fat or water. This information is then utilized to generate water‐only composite images. The principle is demonstrated in free‐breathing abdominal and neck examinations using stack‐of‐stars 3D balanced SSFP (bSSFP) and gradient‐recalled echo (GRE) sequences at 0.55 and 3T. Moreover, a potential extension toward quantitative fat/water separation is described.

Results

Experiments with a proton density fat fraction (PDFF) phantom validated the reliability of fat/water separation using signal‐response curves. As demonstrated for abdominal imaging at 0.55T, the approach resulted in more uniform fat suppression without loss of water signal and in improved CSF‐to‐fat signal ratio. Moreover, the approach provided consistent fat suppression in 3T neck exams where conventional spectrally‐selective fat saturation failed due to strong local B0 inhomogeneities. The feasibility of simultaneous fat/water quantification has been demonstrated in a PDFF phantom.

Conclusion

The proposed principle achieves reliable fat suppression in low‐field applications and adapts to high‐field applications with strong B0 inhomogeneity. Moreover, the principle potentially provides a basis for developing an alternative approach for PDFF quantification.
Assessment of the changes in the petrous portion of temporal bone (pars petrosa ossis temporalis) under the influence of high temperature during the cremation process
Authors: Mackiewicz Klementyna , Pawelec Łukasz , Šimon Jan , Szczurowski Jacek
Published: June 2024

The petrous parts of temporal bones are considered to be the densest parts of the human skeleton. Because of their high biomechanical strength, these elements can be preserved well even exposed to destructive processes. It has been proved that these bones are very well preserved in cremation graves and thus can be used as the foundation for anthropological analyses of cremated remains. The aim of the study was to determine the degree of shrinkage of the petrous portion of temporal bone under the influence of high temperature during the cremation. In a modern crematorium in Prague (Czech Republic), an experiment was conducted by burning 15 human temporal bones and a fresh pig's heads with soft tissues. Nine measurements were collected from each bone before the burning process. Cremation was carried out under controlled conditions in a modern cremation oven—the process took 45 min, and the temperature reached 1000°C. All the bones were burned together to maintain the same experimental conditions. Measurements of the individual bones were then repeated, and the significance of the dimensional changes was assessed. The presented study pointed out the significant size's reduction at level to 14% for dry petrous parts of temporal bones, while the size of fresh bones changed to 28% of their mass depending on the examined feature. Furthermore, the results of comparative analyses revealed that the differences between burning of dry and fresh bones are insignificant.
Public sector leadership in leadership scholarship: A systematic literature review
Authors: Dandalt Ed
Published: June 2024

This paper provides a systematic review of some of the research streams characterizing the body of leadership literature on public sector leadership as informed by traditional leadership journals. It notes that the public sector is extensively studied by leadership scholars. Among the research streams found in that scholarship are administrative leadership, political leadership, and reforms/innovations. It also proposes directions for future research.
Wearable skin integrated flexible PVA‐nickel nanocomposite patch for temperature sensor
Authors: Gudadur Kavitha Sharanappa , Kumar Avinash , Veluswamy Pandiyarasan
Published: June 2024

The study focuses on developing a noninvasive, flexible polyvinyl alcohol (PVA)‐nickel (Ni) nanocomposite thin film as a passive skin‐integrated patch sensor for wearable temperature monitoring, marking a significant advancement in the field of wearable sensors. This flexible PVA‐Ni nanocomposite thin film serves as a temperature‐sensitive material, offering several advantages over commercially available active‐type sensors. Field emission scanning electron microscopy (FE‐SEM) images show that Ni nanoparticles (NPs) are broadly dispersed throughout the PVA matrix, indicating the effectiveness of the conductive patch in detecting temperature variations. A PVA‐Ni nanocomposite patch with a thickness of 0.08 mm demonstrated superior flexibility, breathability, and lower tearing strength compared to a pure PVA patch. The film also exhibited excellent repeatability in bending tests, maintaining performance after 120 bending and unloading cycles, suggesting its durability for long‐term use as a wearable sensor. Furthermore, the fabricated sensors function as thermistors, with conductivity increasing linearly with temperature. The performance of these temperature sensors was compared, revealing a highest temperature coefficient of resistance (TCR) and thermal index of −1.08%/°C and 1271 K, respectively. The sensors showed high temperature sensitivity between room temperature and 50°C, outperforming typical commercial platinum temperature sensors. The stability and response time of the PVA‐Ni nanocomposite film were evaluated by adhering the patch to a human wrist and capturing thermal images using a FLIR thermal imaging camera. The observed maximum temperature difference of approximately 1.9–2.1°C highlights the patch's sensitivity in detecting temperature changes. Additionally, the antimicrobial properties of the conductive film were tested to assess its biocompatibility, confirming its potential for applications in energy storage, thermal management, and early breast cancer detection.
An efficient method to prepare high grafting montmorillonite with silane coupling agent and its improvements for styrene butadiene rubber composites
Authors: Peng Zhiliang , Li Yujie , Wang Yiqing , Liu Yuwan , Ding Xiaofang , Wu Xiaohui , Zhang Liqun
Published: June 2024

The quantity of silane chemically bonded to the organoclay's surface significantly influences its dispersion within the polymer matrix, as well as the interfacial interaction. This research presents a groundbreaking method for enhancing the surface properties of montmorillonite (Mt) through the use of γ‐(methacryloxy) propyl trimethoxy silane (KH570) coupled with acid treatment, leading to increased grafting efficiency. Confirmed by FT‐IR, TGA, and XRD, the process effectively bonds organo‐silanes to Mt and achieves a high grafting level of 1.59 mequiv/g. Utilizing a latex compounding method, Mt/rubber nanocomposites are synthesized with thoroughly modified clay for peak performance. Dispersion and interfacial properties are evaluated through XRD, TEM, AFM, and DMTA. The findings reveal that the well‐modified Mt is an exceptional filler, ensuring a high level of dispersion and robust interaction with the rubber matrix. This synergy translates to a marked improvement in the mechanical properties of the composite, with notable enhancements observed in both tensile strength and elongation at break of 9.7 MPa and 1141%, respectively. This innovative approach to the graft modification of clays presents a potent method, offering the potential for the industrial‐scale manufacture of high‐performance clay‐based composites.

Highlights

A processing method for preparing high grafting clay with a silane coupling agent.

Functionalized clay presents better nano‐dispersion in the polymeric matrix.

Strong covalent interfacial interaction is constructed between clay and rubber.

Tensile Strength and elongation at break of the composites are obliviously improved.
Sleep‐disordered breathing on respiratory polygraphy in neonates with spina bifida
Authors: Wachsmuth Lorine , Bieli Christian , Grehten Patrice , Moehrlen Theres , Moehrlen Ueli , Bernet Vera , Hagmann Cornelia ,   Spina Bifida Study Group Zurich, Grass Beate
Published: June 2024

Introduction

Studies have shown a high prevalence of sleep‐disordered breathing (SDB) in children with spina bifida. International standards for regular testing for SDB in this population are lacking. While there are studies investigating the prevalence of SDB in children with spina bifida, there are close to no studies in neonates.

Aim and Objective

To evaluate if routine respiratory polygraphy (RPG) testing is indicated for neonates with spina bifida and if yes, with what therapeutic consequence.

Methods

We conducted a retrospective cohort study of all neonates with spina bifida at the University (Children's) Hospital Zurich after fetal spina bifida repair born between 2017 and 2022, who had undergone at least 1 RPG evaluation during hospitalization on the neonatal ward. RPG were evaluated by a blinded group of experienced pediatric pulmonologists. Based on the neonatal RPG results and pediatric pulmonologist's recommendation for caffeine therapy the spina bifida cohort was divided into two groups. Neonatal baseline RPG and follow‐up RPG at the age of the 3 months were evaluated.

Results

48 neonates with RPG were included. Compared to the standard values in healthy neonates, the RPG results of this spina bifida cohort showed findings of SDB with central apnea and hypopnea. 22 (45.8%) neonatal RPG evaluations detected central SDB, prompting caffeine therapy. Follow‐up RPG conducted after 3 months showed significant improvement of SDB with (almost) no need for continuation of caffeine.

Conclusion

We recommend the implementation of routine RPG testing in neonates with spina bifida to detect SDB and facilitate early targeted treatment.
How to Control Excited‐State Prototropism of Photoacids via the Acidity of Ionic Liquids
Authors: Kasana Preeti , Saloni  , Kumar Vinod
Published: June 2024

To control presence of ionic species in excited state of a fluorophore is quite challenging task. Herein, we report the unusual excited‐state prototropism of an important photoacid carbazole dissolved in water in presence of small amount of added ionic liquids (ILs). We have observed that the excited state prototropic equillibria of carbazole dissolved in water can be affected by the presence of small amount of added ILs. More importantly, the excited‐state prototropism of carbazole can be controlled via the acidity of added ILs. More specifically, we found that the fluorescence emission from the neutral prototropic form of carbazole can be observed even under highly basic conditions (aqueous NaOH, pH 12.6) in presence of only small amount of any of the added ILs such as 1‐butyl‐3‐methyl imidazolium tetrafluoroborate ([bmim][BF4]), 1‐butyl‐1‐methylpyrrolidinium bis(trifluromethansulphonyl)imide ([bmpyrr][Tf2N]) and 1‐butyl‐3‐methyl imidazolium hexafluorophosphate ([bmim][PF6]). The observed fluorescence emission from the neutral form of carbazole can be attributed to excited state protonation of carbazole anion by taking proton from IL cation. In a true sense, the excited state carbazole does not transfer the proton; rather takes the proton from IL cation. The observed unusual excited state protonation of carbazole anion to neutral carbazole, in the excited state even in highly basic conditions can be attributed to the presence of acidic protons with the IL cations. Herein, we reports quite unusual results where the IL assisted excited state protonation of carbazole anion occured in an exclusive manner in which proton from the IL cation exclusively protonate carbazole anion surrounded by highly alkaline media (water, pH 12.6). ILs acidity controlled excited‐state properties of important photoacids can have a wide range of chemical and biological applications and the observed results can play important roles in chemical technology to control prototropic equillibra with the help of ILs for some specific application. These observations can open new windows to attract more applications for these alternative solvent media to applications in pH and pOH jump experiments, effective photo protecting agents and chemical lasers.
Effect of Chitosan‐Silver Nanoparticles on DEN‐induced Hepatocellular Injury by Regulation of Wnt/β‐Catenin and Apoptosis Signaling Pathways in Rats
Authors: Nasef Shaimaa M. , Mohamed Hebatallah E. , Mansour Somya Z.
Published: June 2024

Silver nanoparticles (AgNPs) have gained remarkable attention as therapeutic agents since the appearance of nanotechnology. This study aims to assess the protective impact of chitosan‐silver nanoparticles (CS‐AgNPs) against DEN‐induced hepatocellular injury by regulation of Wnt/β‐Catenin and apoptosis signaling pathways in rats. CS‐AgNPs solutions were prepared by mixing different concentrations of chitosan and silver nitrate, and then subjected to gamma radiation at 20 kGy. The formation of CS‐AgNPs could be observed by naked eyes from the colour change from light yellow to reddish‐brown, and confirmed by dynamic light scattering (DLS) and transmission electron microscopy (TEM). Stability measurements confirmed that the prepared Cs‐AgNPs are highly stable for around 8 weeks. A crystal violet cytotoxicity assay of CS‐AgNPs has been detected in vitro on HepG2 hepatocellular carcinoma cell lines. The obtained results confirmed the selective influence of CS‐AgNPs on the HCC cell line in a time and dose dependent manner. Diethylnitrosamine (DEN) induced a marked increase in the expressions of Wnt, β‐Catenin, STAT3, MMP9, and Bcl‐2 with a significant decrease in the expression of BAX, p53, and P21. Additionally, DEN significantly decreased the levels of Cytc and TPTH while significantly increased the levels of COX‐2, PGE2, TGF‐1, AFP, and liver enzyme activity. The role of CS‐AgNPs is documented in diminishing the expressions of Wnt, β‐Catenin, STAT3, MMP9, and Bcl‐2. Also, CS‐AgNPs induced the decrease in the levels of COX‐2, PGE2, TGF‐1, AFP and liver enzyme activity accompanied by increased apoptosis. These results concluded that CS‐AgNPs might be a promising drug designed for treating liver diseases.
Semisynthesis: An Essential Tool for Antibiotics Drug Discovery
Authors: Goel Bharat , Tripathi Nancy , Bhardwaj Nivedita , Pal Singh Inder , Jain Shreyans K.
Published: June 2024

The continuous emergence of antimicrobial resistance (AMR) is a serious threat to humans. The discovery and development of new antibiotics having new modes of action are the global need to save mankind. Natural products (NPs) have played a central role in antibiotics drug discovery. Although biologically active, natural products pose some critical issues in their therapeutic uses, including supply issues, pharmacokinetic properties, drug resistance, and toxicity. Semisynthesis holds promise in the discovery and development of antibiotics, offering a strategic approach to overcome challenges associated with antibiotic resistance and optimize the therapeutic properties of existing compounds. Semisynthesis strategies have been used to improve the antimicrobial activities of natural products. By modifying natural compounds, researchers can create derivatives that target specific bacterial pathways or mechanisms, potentially expanding the range of bacterial infections that can be effectively treated with an increased spectrum of resistance. The present review describes NP‐derived semisynthetic antibiotics approved between 1981 and 2022.
Unveiling the Multifaceted Nature of 4‐(4‐Methylphenyl Thio)benzophenone: Electronic Structure and Excited States in Gas Phase and Solvents
Authors: Bhatia Manjeet
Published: June 2024

Benzophenone and its derivatives are widely used as UV filters and UV‐ink photoinitiators. The photoinitiating properties of benzophenones depend on their degree of conjugation and delocalization within the molecule. By understanding how conjugation, delocalization, and different substituents affect these properties, benzophenone derivatives can be customized for specific applications. Using quantum mechanical calculations based on B3LYP/6‐311++G(d, p) density functional theory (DFT), chemical reactivity, stability, and photoinitiating capabilities of 4‐(4‐methylphenylthio)benzophenone are analyzed. This includes studying its physical and chemical properties in the gas phase, as well as its excited state electronic transitions, vibrational characteristics, and spectroscopic properties both in gas phase and in various solvents. The DFT‐computed infrared spectra match experimental results. The UV/Visible spectra shows absorption towards longer wavelengths due to extended delocalization of π‐electrons. In different solvents with varying polarity, the absorption spectra exhibit high‐intensity peaks, shift in excitation energy and wavelengths based on the polarity of the solvent. This knowledge allows for the development of novel initiators with customized light absorption, excited state lifetimes, and reaction selectivities, which can enhance processes like UV‐curing, photopolymerization, and other light‐driven reactions.
Growth of ZnO thin Films from Depleted Batteries for Water Remediation
Authors: Melia L. F. , Gallegos M. V. , Juncal L. , Rabal S. , Hernández‐Fenollosa M. A. , Ibañez F. J. , Meyer M. , Damonte L. C.
Published: June 2024

ZnO films were obtained by electrodeposition technique from commercial Zn2+ solutions and those obtained from spent alkaline batteries. The type of counterion and pH impact directly on the structural, morphological, and optical properties of the electrodeposited ZnO films. The morphological and crystallographic orientation differences observed by X‐ray diffraction (XRD) analysis and high‐resolution field emission scanning electron microscopy (HR‐FESEM), demonstrates the influence of the type and origin of precursors used in the ZnO synthesis process. Those samples grown from commercial nitrate solutions exhibit nanocolumns revealing a preferential growth in the (002) direction. On the other hand, random growth (hexagonal plates, agglomerations, clusters, etc.) is observed in samples obtained through recycled solutions. All deposited samples achieved a transparency close to 80 % and an optical band gap of around 3.30 eV. The as‐deposited films were evaluated toward the photodegradation capacity of methylene blue (MB) for potential technological applications. Results exhibit that samples prepared from recycled ZnCl2 solutions presented more than 80 % degradation per mass of ZnO. This work demonstrates a virtuous circle since ZnO films are deposited by a facile and scalable technique from discarded batteries and used for MB photodegradation. Furthermore, the simplicity of recovery of these substrates after application makes them an attractive and pragmatic option for a range of water treatment applications. Synopsis: Zinc from depleted alkaline batteries is reused to obtain ZnO thin films that remove contaminating dyes from water.
Tunable Synthesis of Pyrazolo Oxepines, Pyrazolo Thiophenes and 1H‐Indazoles Using Alkylation, Aldol Condensation and Thermal Rearrangement
Authors: Pitchai Manivel , Ulaganathan Sankar , Reddy Thirupala , Chikkananjaiah Nanjundaswamy Kanikahalli , Venkateshappa Suresh Shagathur , Byri Vijay Kumar , Akunuri Arun , Pavan Mysore S. , Vetrichelvan Muthalagu , Mathur Arvind , Gupta Anuradha
Published: June 2024

Base‐mediated alkylation of 1‐alkyl/aryl‐5‐hydroxy/mercapto‐1H‐pyrazole‐4‐carbaldehydes with functionalized 3‐bromo‐prop‐1‐enes and 3‐bromo‐1‐(arylsulfonyl)propenes followed by intra‐molecular cyclization afforded regioselective pyrazolo oxepines, pyrazolo thiophenes, and 1H indazoles respectively, with good to excellent yields. This protocol paves the way for the development of syntheses of interesting biologically active scaffolds.
Revolutionizing Indole Synthesis: A Microwave‐Powered Approach
Authors: Nigam Vaibhav , Singh Surbhi , Kasana Shivani , Kumar Shivam , Das Kurmi Balak , Das Gupta Ghanshyam , Patel Preeti
Published: June 2024

Tempted by the unique medicinal and biological potential of indole‐containing heterocycles, chemists, especially those specializing in heterocycle synthesis and drug discovery, are actively pursuing their efficient construction. This review spotlights the latest advancements in microwave‐assisted (M. W.) synthesis of diverse indole‐based heterocyclic compounds. We systematically categorize the reported methods based on the specific indole substitution patterns. This review concise the microwave assisted synthesis of indole based‐pyridine derivatives, indole based‐pyrimidine, indole based‐oxindole, spiro‐oxindole, Fischer indole Heck‐isomerization derivatives, functionalized indole, substituted indoles, indolyl quinoline, indole triazole and indolylnicotinonitriles derivatives. Ultimately, this review aims to provide organic and medicinal chemists with a concise yet informative guide to recent methodologies employing indole derivatives in the microwave‐powered synthesis of heterocycles.
Hybrid mutation driven testing for natural language inference
Authors: Meng Linghan , Li Yanhui , Chen Lin , Ma Mingliang , Zhou Yuming , Xu Baowen
Published: June 2024

Natural language inference (NLI) is a task to infer the relationship between the premise and hypothesis sentences, whose models have essential applications in the many natural language processing (NLP) fields, for example, machine reading comprehension and recognizing textual entailment. Due to the data‐driven programming paradigm, bugs inevitably occur in NLI models during the application process, which calls for novel automatic testing techniques to deal with NLI testing challenges. The main difficulty in achieving automatic testing for NLI models is the oracle problem; that is, it may be too expensive to label NLI model inputs manually and hence be too challenging to verify the correctness of model outputs. To tackle the oracle problem, this study proposes a novel automatic testing method hybrid mutation driven testing (HMT), which extends the mutation idea applied in other NLP domains successfully. Specifically, as there are two sets of sentences, that is, premise and hypothesis, to be mutated, we propose four mutation operators to achieve the hybrid mutation strategy, which mutate the premise and the hypothesis sentences jointly or individually. We assume that the mutation would not affect the outputs; that is, if the original and mutated outputs are inconsistent, inconsistency bugs could be detected without knowing the true labels. To evaluate our method HMT, we conduct experiments on two widely used datasets with two advanced models and generate more than 520,000 mutations by applying our mutation operators. Our experimental results show that (a) our method, HMT, can effectively generate mutated testing samples, (b) our method can effectively trigger the inconsistency bugs of the NLI models, and (c) all four mutation operators can independently trigger inconsistency bugs.
Two sides of the same coin: A study on developers' perception of defects
Authors: Santos Geanderson , Muzetti Igor , Figueiredo Eduardo
Published: June 2024

Software defect prediction is a subject of study involving the interplay of software engineering and machine learning. The current literature proposed numerous machine learning models to predict software defects from software data, such as commits and code metrics. Further, the most recent literature employs explainability techniques to understand why machine learning models made such predictions (i.e., predicting the likelihood of a defect). As a result, developers are expected to reason on the software features that may relate to defects in the source code. However, little is known about the developers' perception of these machine learning models and their explanations. To explore this issue, we focus on a survey with experienced developers to understand how they evaluate each quality attribute for the defect prediction. We chose the developers based on their contributions at GitHub, where they contributed to at least 10 repositories in the past 2 years. The results show that developers tend to evaluate code complexity as the most important quality attribute to avoid defects compared with the other target attributes such as source code size, coupling, and documentation. At the end, a thematic analysis reveals that developers evaluate testing the code as a relevant aspect not covered by the static software features. We conclude that, qualitatively, there exists a misalignment between developers' perceptions and the outputs of machine learning models. For instance, while machine learning models assign high importance to documentation, developers often overlook documentation and prioritize assessing the complexity of the code instead.
Trajectory tracking attack for vehicular ad‐hoc networks
Authors: Li Changrong , Li Zhenfu
Published: June 2024

Maintaining user privacy and security is a critical concern in vehicular ad hoc networks (VANETs). However, prior research has neglected the study of matrix recovery attack methods in VANETs and the challenge of reducing the number of roadside units (RSUs). In this article, we formulate a path recovery strategy using matrix recovery techniques from an adversarial view. Subsequently, the challenge of minimizing RSUs while monitoring all user vehicles in a region is converted into a set cover problem. We introduce a heuristic algorithm that utilizes clustering to address this issue. To minimize matrix recovery errors, a Kalman filter based method is integrated to enhance the performance. This paper also presents an initial deployment of path recovery attacks, maintaining effectiveness even with certain defense mechanisms in place. Furthermore, we conduct simulation experiments to evaluate the effectiveness of the proposed attack strategy. The simulation results demonstrate the performance across various dimensions. Finally, the results show that the success rate of our proposed counter‐defense strategy in overcoming user defenses surpasses 50%.
Experimental and analytical study on the load‐bearing capacity of segmented tower structures with dry joints under combined loading
Authors: Fürll Florian , Klein Fabian , Hartwig Steffen , Kang Chongjie , Betz Thorsten , Marx Steffen
Published: June 2024

In recent years, hybrid towers have become increasingly established, especially for tall wind turbines. The concrete part of these towers, commonly constructed using segmental construction methods, consists of several circular ring segments stacked on top of each other. To reduce the amount of fabrication and erection effort, the joints between the segments are typically designed as dry ground joints. This paper deals with experimental investigations to determine the torsional load‐bearing capacity of such dry ground concrete joints subjected to combined loading of prestressing, bending, and torsion. Based on the experience of previous investigations, a test set‐up consisting of three reinforced concrete segments with circular ring cross‐sections was developed. The herein newly developed evaluation concept enabled precise identification of the failure point for each test run utilizing the measured tangential displacements of the joint. The test results clarify the weaknesses of the current design model regarding the insufficient interaction with the bending moment and show very good accordance with the new calculation model, the so‐called fiber model.
Experimental verification of full‐scale silo structure demolition: Investigating successive column removal with finite element method and progressive collapse simulation through blast load
Authors: Yuzbasi Julide
Published: June 2024

This article presents an experimental and numerical study of the collapse behavior of a 60‐m‐high cement silo structure under blast loading, analyzed using SAP2000 (FEM‐NDA) and LS‐DYNA (FEM‐NDA‐explicit code) models to simulate the collapse mechanism. Considering the seismic events in Kahramanmaras, Turkiye, on February 6, 2023, with magnitudes of 7.8 and 7.6, the necessity for the explosive demolition of hundreds of thousands of structures has underscored the urgency of rapid planning. This situation requires a particular focus on the expeditious analysis of demolition methodologies. The study includes pre‐planning stages, sudden column removals and the detonation of columns with blast loads for the controlled demolition of a full‐scale existing silo structure. To overturn the structure, the columns inside the wedge region were suddenly removed using SAP2000 nonlinear dynamic analysis (NDA) to understand the subsequent load redistribution. A study was conducted to compare the use of shell and plate elements in SAP2000 for a 1‐m‐thick wall silo. The results showed that using shell elements provided relatively closer results to real values than plate elements. For the explicit analysis part, the structural components were modeled as solid materials, and columns were detonated with blast loads. The models and actual demolition frame‐by‐frame results of the structure were compared, and the numerical model's accuracy was validated using experimental data from stationary cameras and drones, with the explicit analysis results found to be in agreement. While explicit analysis yielded results more in line with real data, SAP2000 NDA provided relatively distant results, although SAP2000‐NDA was more time‐efficient compared to explicit analysis models. However, a preliminary evaluation can be made if the characteristics of both programs are understood. The documented information on full‐scale structure demolition and findings presented in this paper will serve as a resource for future studies and provide a reference for researchers.
Environmental impact assessment for large carnivores: a methodological review of the wolf Canis lupus monitoring in Portugal
Authors: Ferrão da Costa Gonçalo , Mascarenhas Miguel , Fonseca Carlos , Sutherland Chris
Published: June 2024

The continuous growth of the global human population results in increased use and change of landscapes, with infrastructures like transportation or energy facilities being a particular risk to large carnivores. Environmental impact assessments were established to identify the probable environmental consequences of any new proposed project, find ways to reduce impacts, and provide evidence to inform decision making and mitigation. Portugal has a wolf population of approximately 300 individuals, designated as an endangered species with full legal protection. They occupy the northern mountainous areas of the country which has also been the focus of new human infrastructures over the last 20 years. Consequently, dozens of wolf monitoring programs have been established to evaluate wolf population status, to identify impacts, and to inform appropriate mitigation or compensation measures. We reviewed Portuguese wolf monitoring programs to answer four key questions. Do wolf programs examine adequate biological parameters to meet monitoring objectives? Is the study design suitable for measuring impacts? Are data collection methods and effort sufficient for the stated inference objectives? Do statistical analyses of the data lead to robust conclusions? Overall, we found a mismatch between the stated aims of wolf monitoring and the results reported, and often neither aligns with the existing national wolf monitoring guidelines. Despite the vast effort expended and the diversity of methods used, data analysis makes almost exclusive use of relative indices or summary statistics, with little consideration of the potential biases that arise through the (imperfect) observational process. This makes comparisons of impacts across space and time difficult and is therefore unlikely to contribute to a general understanding of wolf responses to infrastructure‐related disturbance. We recommend the development of standardized monitoring protocols and advocate for the use of statistical methods that account for imperfect detection to guarantee accuracy, reproducibility, and efficacy of the programs.
Complete Left Tail Asymptotic for the Density of Branching Processes in the Schröder Case
Authors: Kutsenko Anton A.
Published: June 2024

For the density of Galton-Watson processes in the Schröder case, we derive a complete left tail asymptotic series consisting of power terms multiplied by periodic factors.
The effect of incidental dose to pelvic nodes in bladder-only irradiation in the era of IMRT: a dosimetric study
Authors: Ozyigit Gokhan , Kahvecioglu Alper , Cengiz Mustafa , Yedekci Fazli Yagiz , Hurmuz Pervin
Published: June 2024

Purpose

While three-dimensional radiotherapy (RT) causes high incidental nodal doses in bladder-only irradiation for muscle-invasive bladder cancer (MIBC), the impact on pelvic lymphatics is unclear in the era of intensity-modulated RT (IMRT). This study evaluates incidental doses to pelvic lymphatics in MIBC patients treated with IMRT.

Methods

The data of 40 MIBC patients treated with bladder-only IMRT and concurrent chemotherapy were retrospectively evaluated. The pelvic lymphatics were contoured on initial simulation images and incidental nodal doses were evaluated. The Statistical Package for the Social Sciences (SPSS) version 23.0 (IBM, Armonk, NY, USA) was used for statistics.

Results

Median RT dose to the bladder was 60 Gy in 30 fractions. In dosimetric analysis, median values of mean dose (Dmean) of the obturator, presacral, external iliac, internal iliac, and distal common iliac lymphatics were 33 Gy (range 4–50 Gy), 3 Gy (range 1–28 Gy), 9.5 Gy (range 3–41 Gy), 7.5 Gy (range 2–14 Gy), and 1 Gy (range 0–15 Gy), respectively. The Dmean of the obturator lymphatics was significantly higher (p < 0.001) and the Dmean of the distal common iliac lymphatics was significantly lower (p < 0.001) than all remaining lymphatic stations. The Dmean of the external iliac lymphatics was significantly higher than that of the presacral lymphatics (p < 0.001), but the difference with the internal iliac lymphatics was not statistically significant (p = 0.563).

Conclusion

The incidental nodal doses with bladder-only IMRT are heterogeneous and remain below the generally accepted doses for microscopic disease eradication for bladder cancer.