bluuebunny/crossref_metadata_2025 huggingface dataset:
Prognostic significance of pulmonary arterial wedge pressure estimated by deep learning in acute heart failure
Authors: Saito Yuki , Omae Yuto , Mizobuchi Saki , Fujito Hidesato , Miyagawa Masatsugu , Kitano Daisuke , Toyama Kazuto , Fukamachi Daisuke , Toyotani Jun , Okumura Yasuo
Published: December 2022

Aims

Acute decompensated heart failure (ADHF) presents with pulmonary congestion, which is caused by an increased pulmonary arterial wedge pressure (PAWP). PAWP is strongly associated with prognosis, but its quantitative evaluation is often difficult. Our prior work demonstrated that a deep learning approach based on chest radiographs can calculate estimated PAWP (ePAWP) in patients with cardiovascular disease. Therefore, the present study aimed to assess the prognostic value of ePAWP and compare it with other indices of haemodynamic congestion.

Methods and results

We conducted a post hoc analysis of a single‐centre, prospective, observational heart failure registry and analysed data from 534 patients admitted for ADHF between January 2018 and December 2019. The deep learning approach was used to calculate ePAWP from chest radiographs at admission and discharge. Patients were divided into three groups based on the ePAWP tertiles at discharge, as follows: first tertile group (ePAWP ≤ 11.2 mm Hg, n = 178), second tertile group (11.2 < ePAWP < 13.5 mm Hg, n = 170), and third tertile group (ePAWP ≥ 13.5 mm Hg, n = 186). The third tertile group had a higher prevalence of atrial fibrillation and lower systolic blood pressure at admission; a lower platelet count and higher total bilirubin at both admission and discharge; and a higher left atrial diameter, peak early diastolic transmitral flow velocity, right ventricular end‐diastolic diameter, and maximal inferior vena cava diameter at discharge. During the median follow‐up period of 289 days, 223 (41.7%) patients reached the primary endpoint (a composite of all‐cause mortality or rehospitalization for heart failure). Kaplan–Meier analysis revealed a significantly higher composite event rate in the third tertile group (log‐rank test, P = 0.006). Even when adjusted for clinically relevant factors, a higher ePAWP at discharge and a smaller decrease in ePAWP from admission to discharge were significantly associated with higher event rates [ePAWP at discharge: hazard ratio, 1.10; 95% confidence interval (CI), 1.02–1.19; P = 0.010; and size of ePAWP decrease: hazard ratio, 0.94; 95% CI, 0.89–0.99; P = 0.038].

Conclusions

Our study suggests that ePAWP calculated by a deep learning approach may be useful for identifying and monitoring pulmonary congestion during hospitalization for ADHF.
Deep learning based seismic response prediction of hysteretic systems having degradation and pinching
Authors: Kim Taeyong , Kwon Oh‐Sung , Song Junho
Published: December 2022

The response of a hysteretic system is determined not only by the instantaneous external force but also by the loading history; thereby, a nonlinear time history analysis is needed for the accurate prediction of dynamic responses. The authors recently developed deep neural network (DNN) models for near‐real‐time seismic response predictions of hysteretic systems (Kim et al., 2019). The DNN models outperform existing regression‐based prediction methods for the idealized hysteretic systems used for the training. Structural systems often show complex hysteretic behavior such as degradation (in stiffness or strength) and pinching effects. In this paper, we develop DNN models for hysteretic systems having degradation and pinching. First, a new Bouc‐Wen class model, termed a modified Bouc‐Wen‐Baber‐Noori (m‐BWBN) model, is proposed to introduce the yield strength as an explicit model parameter. The feasible parameter domains are also specified to promote the practical use of the m‐BWBN model. Second, a seismic demand database is constructed by nonlinear time history analyses using the m‐BWBN model and many ground motions. Third, we propose a new DNN architecture and detailed training methodologies to learn the effects of the complex hysteretic characteristics on the peak seismic responses. Numerical examples of reinforced concrete structures are introduced to test the prediction performance and applicability of the proposed DNN model. The source codes, data, and trained models are available for download at http://ERD2.snu.ac.kr.
Outdoor Atmospheric Micro-/Nanomineral-Mediated Organochlorine Pesticides in Sichuan Basin, China: Adsorption, Occurrence, and Risk Assessment
Authors: Lv Zhenzhen , Dong Faqin , Li Hailong , Zhou Lin , Zhang Wen , Zheng Fei , Wang Qiming , Liu Mingxue , Huo Tingting , Zhao Yulian
Published: December 2022

Atmospheric micro-/nanominerals play an important role in the adsorption, enrichment, and migration of organochlorine pesticides (OCPs). In the present study, the correlations between OCPs and minerals in outdoor atmospheric dustfall were investigated, and the correlations were used to speculate the source of p,p′-(dicofol+dichlorobenzophenone [DBP]), which is the sum of p,p′-dicofol and p,p′-DBP. Atmospheric dustfall samples were collected from 53 sites in the Chengdu–Deyang–Mianyang economic region in the Sichuan basin. In this region, 24 OCPs were analyzed by gas chromatography–tandem mass spectrometry. The average concentration of 24 OCPs was 51.2 ± 27.4 ng/g. The results showed that the concentration of Σ24OCPs in urban areas was higher than that in suburban areas (p < 0.05). Minerals in atmospheric dustfall were semiquantitatively analyzed by X-ray diffraction. The primary minerals were quartz, calcite, and gypsum. A Spearman correlation analysis of OCPs and minerals showed that low-volatility OCPs could be adsorbed by minerals in atmospheric dustfall. A density functional theory simulation verified that p,p′-(dicofol+DBP) in atmospheric dustfall was primarily derived from the p,p′-dicofol adsorbed by gypsum. Isomeric ratio results suggested that the samples had weathered lindane and chlordane profiles and confirmed that residents in the Sichuan basin used technical dichlorodiphenyltrichloroethane. Finally, the OCPs were evaluated to determine the potential risk of cancer in adults and children from OCP exposure. Exposure to OCPs via atmospheric dustfall was safe for adults. The cancer risk for children exposed to OCPs was slightly lower than the threshold value (10–6) under a high dust ingestion rate, which poses a concern. Environ Toxicol Chem 2023;42:594–604. © 2022 SETAC

Abstract

The source of p,p′-(dicofol+dichlorobenzophenone) analyzed by Spearman correlation analysis and density functional theory simulation. DDT = dichlorodiphenyltrichloroethane; HCB = hexachlorobenzene; HCH = hexachlorocyclohexane; DBP = dichlorobenzophenone; DDE = dichlorodiphenyldichloroethylene; DDD = dichlorodiphenyldichlorethane; OCP = organochlorine pesticide.
Psychosocial factors and hippocampal subfields: The Medea‐7T study
Authors: Twait Emma L. , Blom Kim , Koek Huiberdina L. , Zwartbol Maarten H. T. , Ghaznawi Rashid , Hendrikse Jeroen , Gerritsen Lotte , Geerlings Mirjam I. ,   UCC SMART Study Group
Published: December 2022

Specific subfields within the hippocampus have shown vulnerability to chronic stress, highlighting the importance of looking regionally within the hippocampus to understand the role of psychosocial factors in the development of neurodegenerative diseases. A systematic review on psychosocial factors and hippocampal subfield volumes was performed and showed inconsistent results, highlighting the need for future studies to explore this relationship. The current study aimed to explore the association of psychosocial factors with hippocampal (subfield) volumes, using high‐field 7T MRI. Data were from the Memory Depression and Aging (Medea)‐7T study, which included 333 participants without dementia. Hippocampal subfields were automatically segmented from T2‐weighted images using ASHS software. Generalized linear models accounting for correlated outcomes were used to assess the association between subfields (i.e., entorhinal cortex, subiculum, Cornu Ammonis [CA]1, CA2, CA3, dentate gyrus, and tail) and each psychosocial factor (i.e., depressive symptoms, anxiety symptoms, childhood maltreatment, recent stressful life events, and social support), adjusted for age, sex, and intracranial volume. Neither depression nor anxiety was associated with specific hippocampal (subfield) volumes. A trend for lower total hippocampal volume was found in those reporting childhood maltreatment, and a trend for higher total hippocampal volume was found in those who experienced a recent stressful life event. Among subfields, low social support was associated with lower volume in the CA3 (B = −0.43, 95% CI: −0.72; −0.15). This study suggests possible differential effects among hippocampal (subfield) volumes and psychosocial factors.
Sperm storage by females across the animal phyla: A survey on the occurrence and biomolecules involved in sperm storage
Authors: Shankar Goutham , Gagan Thumbala A. , Kumari Titus R. S. , Marathe Gopal K.
Published: December 2022

Long‐term sperm storage by females in various regions of the oviduct is documented across many invertebrate and vertebrate species. Although, many reports emphasize on the histology, histochemistry and ultrastructural features of sperm storage, very little is known about the mechanisms underlying the sperm storage. The current review documents the occurrence of sperm storage by females in a wide array of invertebrate and vertebrate species. This review also provides an insight on the presence of various molecular factors of the sperm storage tubules presumably responsible for the prolonged sperm storage with an emphasis on a model reptile, the Indian garden lizard, Calotes versicolor which contains a unique approximately 55‐kDa protein in its utero‐vaginal lavage and found to inhibit washed epididymal sperm motility in a concentration and time‐dependent manner in a reversible fashion.
Patient reported outcome measures in Waldenström macroglobulinaemia: A real‐world data analysis from the WMUK Rory Morrison Registry
Authors: Khwaja Jahanzaib , Uppal Encarl , Bristogiannis Sotirios , McCarthy Helen , Kothari Jaimal , Rismani Ali , Scorer Harriet , Nicholson Jane , El‐Sharkawi Dima , D'Sa Shirley , Kyriakou Charalampia
Published: December 2022

Waldenström macroglobulinaemia (WM) is an incurable chronic B‐cell malignancy, but highly responsive to treatment. Treatments include fixed‐duration chemotherapy and continuous oral chemoimmunotherapy. In this expanding field, it is important to have reliable information on the impact of the various therapies on patients’ quality of life (QoL). Patient reported outcome measures (PROMs) are increasingly recognised as important to understand patient experience of disease beyond traditional clinical outcome measures. Four QoL questionnaires (EORTC QLQ‐C30 [European Organisation for Research and Treatment of Cancer quality of life core questionnaire], BIPQ [Brief Illness Perception Questionnaire], HADS [Hospital Anxiety and Depression Scale], EQ‐5D‐5L [EuroQoL 5‐dimensional descriptive system questionnaire]) are embedded in the UK national WM registry, the Rory Morrison Registry. We reviewed the results from a snapshot of PROMs. As of November 2021, 155 patients completed PROM data with 98% completion rate across all 58 questions. Complete clinical information was available for 52 patients. The majority of QoL questions (69%) failed to elicit a notable median response. Only four questions elicited statistically significant responses when comparing groups, and these were exclusively found in the EuroQoL‐5D‐5L and HADS questionnaires. Our data suggest that widely used questionnaires may not be suitable for patients with WM. We advocate the development of WM‐specific outcome measures to overcome this.
Automated MR Image Prescription of the Liver Using Deep Learning: Development, Evaluation, and Prospective Implementation
Authors: Geng Ruiqi , Buelo Collin J. , Sundaresan Mahalakshmi , Starekova Jitka , Panagiotopoulos Nikolaos , Oechtering Thekla H. , Lawrence Edward M. , Ignaciuk Marcin , Reeder Scott B. , Hernando Diego
Published: December 2022

Background

There is an unmet need for fully automated image prescription of the liver to enable efficient, reproducible MRI.

Purpose

To develop and evaluate artificial intelligence (AI)‐based liver image prescription.

Study Type

Prospective.

Population

A total of 570 female/469 male patients (age: 56 ± 17 years) with 72%/8%/20% assigned randomly for training/validation/testing; two female/four male healthy volunteers (age: 31 ± 6 years).

Field Strength/Sequence

1.5 T, 3.0 T; spin echo, gradient echo, bSSFP.

Assessment

A total of 1039 three‐plane localizer acquisitions (26,929 slices) from consecutive clinical liver MRI examinations were retrieved retrospectively and annotated by six radiologists. The localizer images and manual annotations were used to train an object‐detection convolutional neural network (YOLOv3) to detect multiple object classes (liver, torso, and arms) across localizer image orientations and to output corresponding 2D bounding boxes. Whole‐liver image prescription in standard orientations was obtained based on these bounding boxes. 2D detection performance was evaluated on test datasets by calculating intersection over union (IoU) between manual and automated labeling. 3D prescription accuracy was calculated by measuring the boundary mismatch in each dimension and percentage of manual volume covered by AI prescription. The automated prescription was implemented on a 3 T MR system and evaluated prospectively on healthy volunteers.

Statistical Tests

Paired t‐tests (threshold = 0.05) were conducted to evaluate significance of performance difference between trained networks.

Results

In 208 testing datasets, the proposed method with full network had excellent agreement with manual annotations, with median IoU > 0.91 (interquartile range < 0.09) across all seven classes. The automated 3D prescription was accurate, with shifts <2.3 cm in superior/inferior dimension for 3D axial prescription for 99.5% of test datasets, comparable to radiologists' interreader reproducibility. The full network had significantly superior performance than the tiny network for 3D axial prescription in patients. Automated prescription performed well across single‐shot fast spin‐echo, gradient‐echo, and balanced steady‐state free‐precession sequences in the prospective study.

Data Conclusion

AI‐based automated liver image prescription demonstrated promising performance across the patients, pathologies, and field strengths studied.

Evidence Level

4.

Technical Efficacy

Stage 1.
A new method for segmentation and analysis of bone callus in rodent fracture models using micro‐CT
Authors: Hopkinson Mark , Jones Gareth , Evans Lucinda , Gohin Stephanie , Magnusdottir Ran , Salmon Phil , Chenu Chantal , Meeson Richard , Javaheri Behzad , Pitsillides Andrew A.
Published: December 2022

Fracture burden has created a need to better understand bone repair processes under different pathophysiological states. Evaluation of structural and material properties of the mineralized callus, which is integral to restoring biomechanical stability is, therefore, vital. Microcomputed tomography (micro‐CT) can facilitate noninvasive imaging of fracture repair, however, current methods for callus segmentation are only semiautomated, restricted to defined regions, time/labor intensive, and prone to user variation. Herein, we share a new automatic method for segmenting callus in micro‐CT tomograms that will allow for objective, quantitative analysis of the bone fracture microarchitecture. Fractured and nonfractured mouse femurs were scanned and processed by both manual and automated segmentation of fracture callus from cortical bone after which microarchitectural parameters were analyzed. All segmentation and analysis steps were performed using CTAn (Bruker) with automatic segmentation performed using the software's image‐processing plugins. Results showed automatic segmentation reliably and consistently segmented callus from cortical bone, demonstrating good agreement with manual methods with low bias: tissue volume (TV): −0.320 mm3, bone volume (BV): 0.0358 mm3, and bone volume/tissue volume (BV/TV): −3.52%, and was faster and eliminated user‐bias and variation. Method scalability and translatability across rodent models were verified in scans of fractured rat femora showing good agreement with manual methods with low bias: TV: −3.654 mm3, BV: 0.830 mm3, and BV/TV: 7.81%. Together, these data validate a new automated method for segmentation of callus and cortical bone in micro‐CT tomograms that we share as a fast, reliable, and less user‐dependent tool for application to study bone callus in fracture, and potentially elsewhere.
In vitro anti‐obesity activity by pancreatic lipase inhibition ‐ Simple HPLC approach using EVOO as natural substrate
Authors: Blasi Francesca , Ianni Federica , Mangiapelo Luciano , Pinna Nicola , Cossignani Lina
Published: December 2022

Background

Pancreatic lipase (PL) is a key lipolytic enzyme in humans for the digestion and absorption of dietary fats. Thereby, PL is a well‐recognized target in the management of obesity and its inhibition attracts the interest of researchers globally. The screening of new natural PL inhibitors as alternative strategy to the synthesis of chemical ones represents nowadays a hot topic in research. The main challenge in this matter is the lack of a universal analytical method allowing the monitoring of PL activity and the reliable quantification of lipid digestion products.

Results

The (normal phase)‐high‐performance liquid chromatography‐evaporative light scattering detector [(NP)‐HPLC‐ELSD] method proposed in this work represents a direct and rapid strategy to simultaneously quantify the products obtained from in vitro PL digestion. As one of the main novelties, the triacylglycerol (TAG) fraction from extra‐virgin olive oil was selected as natural substrate. The PL activity was measured by monitoring the levels of remaining TAGs and formed free fatty acids (FFAs), using Orlistat as known inhibitor. The method validation confirmed the adequacy of the analytical method for quantitative purposes, showing high recovery percentage values (between 99% and 103%) and low relative standard deviation (RSD%) values (between 2% and 7%) for triolein and oleic acid standard solutions, as well as appreciably low limit of detection (LOD) and limit of quantification (LOQ) values (respectively 58 and 177 ng mL−1 for triolein; 198 and 602 ng mL−1 for oleic acid). Finally, the developed HPLC‐ELSD method was successfully applied to evaluate the inhibitory effect of a polyphenolic extract obtained from apple pomace. The results showed a comparable inhibition degree between a 4.0 mg mL−1 apple pomace solution and a 1.0 μg mL−1 Orlistat solution.

Conclusion

The proposed innovative method reveals highly sensitive and simple to follow the fate of PL digestion, thus opening the way to further investigations in the research of new potentially anti‐obesity compounds. © 2022 Society of Chemical Industry.
Floquet–Mie Theory for Time‐Varying Dispersive Spheres
Authors: Ptitcyn Grigorii , Lamprianidis Aristeidis , Karamanos Theodosios , Asadchy Viktar , Alaee Rasoul , Müller Marvin , Albooyeh Mohammad , Mirmoosa Mohammad Sajjad , Fan Shanhui , Tretyakov Sergei , Rockstuhl Carsten
Published: December 2022

Exploring the interaction of light with time‐varying media is an intellectual challenge that, in addition to fundamental aspects, provides a pathway to multiple promising applications. Time modulation constitutes here a fundamental handle to control light on entirely different grounds. That holds particularly for complex systems simultaneously structured in space and time. However, a realistic description of time‐varying materials requires considering their material dispersion. The combination thereof has barely been considered but is crucial since dispersion accompanies materials suitable for dynamic modulation. As a canonical scattering problem from which many general insights can be obtained, a self‐consistent analytical theory of light scattering by a sphere made from a time‐varying material exemplarily assumed to have a Lorentzian dispersion is developed and applied. The eigensolutions of Maxwell's equations in the bulk are discussed and a dedicated Mie theory is presented. The proposed theory is verified with full‐wave simulations. Peculiar effects are disclosed, such as energy transfer from the time‐modulation subsystem to the electromagnetic field, amplifying carefully structured incident fields. Since many phenomena can be studied on analytical grounds with the proposed formalism, it represents an indispensable tool that enables exploration of electromagnetic phenomena in time‐varying and spatially structured finite objects of other geometries.
Measurement of lymphatic vessel depth using photoacoustic imaging
Authors: Suzuki Yushi , Kajita Hiroki , Urano Moemi , Watanabe Shiho , Otaki Marika , Takatsume Yoshifumi , Sakuma Hisashi , Imanishi Nobuaki , Kishi Kazuo
Published: December 2022

Objectives

Information regarding the depth of lymphatic vessel is important for lymphatic surgeons because rapid identification of functional lymphatic vessels and veins is necessary to perform good lymphaticovenular anastomosis, which is a surgical procedure for lymphedema cases. Photoacoustic lymphangiography (PAL) may be useful for such identification because it allows the assessment of the depth of lymphatic vessels. Thus, we aimed to measure the lymphatic vessel depth using images obtained by PAL.

Methods

This study included healthy individuals and patients with lymphedema. In all participants, indocyanine green dissolved in dextrose was injected subcutaneously into the first and fourth webs of the foot and the lateral malleolus, and PAL was performed on the medial side of the lower leg. The lymphatic vessel depth was measured from the ankle joint, 10 cm above the medial malleolus, and 20 cm above the medial malleolus on PAL in the cross‐sectional view and was compared between the participant groups.

Results

The healthy group (mean age, 43.3 ± 12.9 years) included 21 limbs of 4 male and 16 female healthy individuals (bilateral limbs of 1 patient were considered). The lymphedema group (mean age, 62.0 ± 11.7 years) included 17 limbs of 3 male and 14 female patients with lymphedema. The average lymphatic vessel depths from the ankle joint, 10 cm above the medial malleolus, and 20 cm above the medial malleolus were 2.6, 4.7, and 5.6 mm in the healthy group and 3.6, 7.3, and 7.4 mm in the lymphedema group, respectively. Lymphatic vessels were significantly deeper in the lymphedema group than in the healthy group at all measurement locations.

Conclusions

Using PAL, we determined the lymphatic vessel depth in living bodies. By searching for the lymphatic vessels based on our findings, even surgeons who are relatively inexperienced with lymphatic surgery may be able to identify functional lymphatic vessels more efficiently.
A 1.62‐W passively Q‐switch Tm3+‐doped laser with a Bi2O2Se saturable absorber
Authors: Zhang Rui , Xun Jiaqi , Shao Mingyu , Ma Hongzhang , Sun Xinghong , Tian Fengjun , Shi Zechang , Yang Xiaotao
Published: December 2022

A saturable absorber based on a novel two‐dimensional (2D) material Bi2O2Se was placed in a resonator with an overall longest diameter of 31 mm to achieve efficient operation of a passively Q‐switched (PQS) Tm:YAP laser for the first time. In PQS mode, a 1.62‐W average output power with a pulse width of 1.24 µs and a pulse repetition of frequency of 112.1 kHz was achieved at the pump power of 22.2 W, corresponding to a peak power of 11.66 W. As a novel 2D material, the results show the potential of Bi2O2Se as a photomodulator in the 2 µm spectral range.
Compact design of monopole antenna for SWB application with high BDR
Authors: Khan Imran , Qiu Hongbing , Rahman Saeed U. , Ahmad Tariq
Published: December 2022

In this paper, a simple and compact monopole antenna with a high bandwidth ratio (BDR) of around is investigated for super wideband (SWB) applications. Using an F4B substrate with a dielectric constant of 2.65, loss tangent of 0.002, and connecting it to a triangular tapered 50‐Ohm line, the suggested antenna achieves its performance objectives. The proposed antenna has an electrical dimension of 0.14λ × 0.22λ and spans the SWB frequency range of 2.89–60 GHz with a 181.5% fractional bandwidth and reflection coefficient S11 < −10 dB. It has been revealed that the results of both experiments and simulations are remarkably similar to one another in terms of their conclusions. In comparison to other SWB antennas, the suggested antenna has a greater BDR, a larger bandwidth, and a more compact size. Apart from that, the antenna has good gain and good radiation characteristics over the whole operational frequency range.
A diode‐pumped SnS2 passively Q‐switched Tm‐doped pulsed laser
Authors: Shi Zechang , Sun Xinghong , Xun Jiaqi , Xie Wenqiang , Zhou Long , Ma Hongzhang , Shao Mingyu , Tian Fengjun , Yang Xiaotao
Published: December 2022

In this research, a diode‐pumped SnS2 passively Q‐switched (PQS) V‐type Tm‐doped pulsed laser was demonstrated. The continuous‐wave (CW) condition without SnS2 saturable absorber (SA) was investigated first. A maximum output power of 1.26W with a slope efficiency of 24.28% was derived at an absorbed pump power of 7.11W under an output coupling of 5%. With the as‐prepared SnS2 SA employed, a series of stable Q‐switched (QS) pulse trains were successfully realized. A minimum pulse width of 3.061 μs and a maximum repetition frequency of 70.42 kHz were generated through an output coupling of 5%, corresponding to a maximum output power of 621 mW. The delivered highest peak power and maximum single pulse energy were 2.90W and 12.41 μJ under an output coupling of 2.5%, respectively. These findings indicated that SnS2 was a promising modulator for 2 μm all‐solid‐state pulsed laser generation.
Monte Carlo‐derived 99mTc uptake quantification with commercial planar MBI: Absolute tumor activity
Authors: Lopez Benjamin P. , Kappadath Srinivas Cheenu
Published: December 2022

Background

Molecular breast imaging (MBI) of 99mTc‐sestamibi is an emerging adjunct qualitative tool in the detection and diagnosis of breast cancer.

Purpose

This work outlines the development and performance evaluation of a methodology to absolutely quantify tumor 99mTc activity uptake using a commercially available dual‐headed MBI system by implementing corrections for background, scatter, attenuation, and detector characteristics.

Methods

A validated Monte Carlo application of a commercial MBI system was used to simulate over 7000 unique acquisitions of spherical and ellipsoidal tumors in breast tissue. Tumor absolute activity was calculated following background, scatter, and attenuation corrections of tumor region of interest counts. The methodology was first optimized using a set of high‐uptake spherical tumors, and its accuracy and precision was then assessed in a set of spherical tumors with clinical uptake conditions. Finally, the performance of the activity methodology was evaluated under various bias and uncertainty conditions to better characterize the technique under expected clinical measurement conditions.

Results

In a test set of images with clinically relevant contrast and noise conditions, the mean ± standard deviation relative error in total tumor activity was 0.5% ± 6.5% (n = 2363) under ideal measurement conditions. Allowing for variability in tumor and background contours and in estimated tumor depths, the expected accuracy of the methodology in clinical practice was 0.5% ± 11.1% (n = 2363), with minimal loss of accuracy for ellipsoidal tumors.

Conclusions

Planar MBI photopeak images acquired with standard‐of‐care protocols can be used to accurately quantify absolute tumor 99mTc activity with an accuracy and precision of 0.5% ± 11.1%. The reported precision was based on a comprehensive evaluation of random errors and systematic biases.
Development of a compact linear accelerator to generate ultrahigh dose rate high‐energy X‐rays for FLASH radiotherapy applications
Authors: Liu Focheng , Shi Jiaru , Zha Hao , Li Guohua , Li An , Gu Weihang , Hu Ankang , Gao Qiang , Wang Haokun , Zhang Liang , Liu Jinsheng , Liu Yaohong , Xu Huijun , Tang Chuanxiang , Chen Huaibi
Published: December 2022

Purpose

In recent years, the FLASH effect, in which ultrahigh dose rate (UHDR) radiotherapy (RT) can significantly reduce toxicity to normal tissue while maintaining antitumor efficacy, has been verified in many studies and even applied in human clinical cases. This work evaluates whether a room‐temperature radio‐frequency (RF) linear accelerator (linac) system can produce UHDR high‐energy X‐rays exceeding a dose rate of 40 Gy/s at a clinical source‐surface distance (SSD), exploring the possibility of a compact and economical clinical FLASH RT machine suitable for most hospital treatmentrooms.

Methods

A 1.65 m long S‐band backward‐traveling‐wave (BTW) electron linac was developed to generate high‐current electron beams, supplied by a commercial klystron‐based power source. A tungsten‐copper electron‐to‐photon conversion target for UHDR X‐rays was designed and optimized with Monte Carlo (MC) simulations using Geant4 and thermal finite element analysis (FEA) simulations using ANSYS. EBT3 and EBT‐XD radiochromic films, which were calibrated with a clinical machine Varian VitalBeam, were used for absolute dose measurements. A PTW ionization chamber detector was used to measure the relative total dose and a plane‐parallel ionization chamber detector was used to measure the relative normalized dose of each pulse.

Results

The BTW linac generated 300‐mA‐pulse‐current 11 MeV electron beams with 29 kW mean beam power, and the conversion target could sustain this high beam power within a maximum irradiation duration of 0.75 s. The mean energy of the produced X‐rays was 1.66 MeV in the MC simulation. The measured flat‐filter‐free (FFF) maximum mean dose rate of the room‐temperature linac exceeded 80 Gy/s at an SSD of 50 cm and 45 Gy/s at an SSD of 67.9 cm, both at a 2.1 cm depth of the water phantom. The FFF radiation fields at 50 cm and 67.9 cm SSD at a 2.1 cm depth of the water phantom showed Gaussian‐like distributions with 14.3 and 20 cm full‐width at half‐maximum (FWHM) values, respectively.

Conclusion

This work demonstrated the feasibility of UHDR X‐rays produced by a room‐temperature RF linac, and explored the further optimization of system stability. It shows that a simple and compact UHDR X‐ray solution can be facilitated for both FLASH‐RT scientific research and clinical applications.
Hochschulpraktika – Cholesterin aus Hirn
Authors: Täuscher Eric , Freiberger Emma
Published: December 2022

Cholesterin hat es bis in den Alltagssprachgebrauch gebracht. Allein deshalb ist es für Praktika im Chemiestudium ein interessanter Vertreter der Steroide. Zudem ist es einfach zu gewinnen.
Trendbericht Festkörperchemie 2023
Authors: Suta Markus , Thiele Günther
Published: December 2022

Die Kristallstruktur von Kohlensäure; multifunktionale Mofs; beschichtete Kugelmühlen für katalytische Anwendungen; nitridische Analoga der Glimmergruppe, die bei Raumtemperatur leuchten; intermetallische Verbindungen für elektrochemische Methanoloxidation und mehr.
Künstliche Photosyntheseprozesse: Kupplungsreaktionen mit CO2
Authors: Pospech Jola , Mayer Thea S.
Published: December 2022

Für Pflanzen ein Leichtes, für Chemiker:innen eine Herausforderung: die stoffliche Umwandlung von Kohlenstoffdioxid. Dabei gibt es bereits Ansätze, Kohlenstoffdioxid als Substrat zu nutzen – sowohl in Homokupplungsreaktionen als auch in Reaktionen mit C‐, N‐ und O‐Nukleophilen. Beispiele der letzten fünf Jahre.
NMR‐Spektroskopie – Von Kriminalistik über Prozessanalytik bis zur Petrochemie
Authors: Ehrensberger Christian
Published: December 2022

Während Analysengeräte vielfach in Miniaturausführung verfügbar sind, beanspruchten NMR‐Systeme bisher viel Stellplatz. Das ändert sich jetzt. Kleinere Geräte und erschwingliche Preise eröffnen neue Anwendungen.
25. Tag der Organischen Chemie an der Universität Stuttgart
Authors: Laschat Sabine
Published: December 2022

Die Corona‐Pandemie hat persönliche Kontakte und das Knüpfen von Netzwerken zwischen Doktoranden, Hochschullehrern und Industrievertretern trotz Online‐Meetings erschwert. Daher bot der diesjährige Tag der Organischen Chemie an der Universität Stuttgart (Tocus) ein willkommenes Forum zum wissenschaftlichen Austausch. Mitte Oktober stellten zwölf Doktoranden ihre Forschungsergebnisse in Kurzvorträgen vor.
Board Meeting
Authors: Koch Wolfram
Published: December 2022

Report on the Meeting of the GDCh Board on September 7, 2022 in Gießen
A meshless finite point method for the improved Boussinesq equation using stabilized moving least squares approximation and Richardson extrapolation
Authors: Li Xiaolin
Published: December 2022

A meshless finite point method (FPM) is developed in this paper for the numerical solution of the nonlinear improved Boussinesq equation. A time discrete technique is used to approximate time derivatives, and then a linearized procedure is presented to deal with the nonlinearity. To achieve stable convergence numerical results in space, the stabilized moving least squares approximation is used to obtain the shape function, and then the FPM is adopted to establish the linear system of discrete algebraic equations. To enhance the accuracy and convergence order in time, the Richardson extrapolation is finally incorporated into the FPM. Numerical results show that the FPM is fourth‐order accuracy in both space and time and can obtain highly accurate results in simulating the propagation of a single solitary wave, the interaction of two solitary waves, the solitary wave break‐up and the solution blow‐up phenomena.
Casting hydrophilic polymers blended polycaprolactone membranes for drug delivery to eradicate the cancer cells and pathogenic microorganisms
Authors: Pavithra Marimuthu E. , Jayaraman Rengaramanujam , Azarudeen Raja S. , Thirumarimurugan Marimuthu
Published: December 2022

Hydrophilic polymers have been recognized for enhancing the physico‐chemical and biological properties of synthetic polyesters in the field of cancer treatment and tissue engineering. In this article, the anticancer drug, 5‐fluorouracil loaded membranes were prepared with polycaprolactone blended with chitosan, hydroxypropyl methyl cellulose and polyethylene glycol to study the drug release ability for breast cancer treatment alongside microbial infections. Solution casting method was employed to fabricate blend membranes with a combination of synthetic, natural and hydrophilic polymers and the resulted membranes were characterized by spectral, crystallographic, surface morphology, contact angle measurements and mechanical testing. Through spectral and crystallographic study, the crosslinking and chemical interactions between the drug and polymers were confirmed. Swelling capacity, drug loading efficiency and the drug release profile were studied and an optimal release of drug from the membranes was observed. The membranes showed cell viability of 60%–85% against fibroblast cell line and cytotoxicity of 60%–76% against breast cancer cells. Furthermore, microbial growth inhibition assay results revealed that the membranes possess good inhibiting property for the selected bacterial and fungal strains. The in vitro degradation studies reveals that the degradation rate of the blend membranes was found higher compared to the bare membrane. Hence, the obtained results clearly reveals that the fabricated membranes would be a promising biomaterial implant in the treatment of breast cancer cells and post‐surgical microbial infections.
Gradual increase in sweat chloride concentration is associated with a higher risk of CRMS/CFSPID to CF reclassification
Authors: Salinas Danieli B. , Ginsburg Daniella K. , Wee Choo Phei , Saeed Muhammed M. , Brewington John J.
Published: December 2022

Objectives

Universal implementation of cystic fibrosis (CF) newborn screening (NBS) has led to the diagnostic dilemma of infants with CF screen‐positive, inconclusive diagnosis (CFSPID), with limited guidance regarding prognosis and standardized care. Rates of reclassification from CFSPID to CF vary and risk factors for reclassification are not well established. We investigated whether clinical characteristics are associated with the risk of reclassification from CFSPID to a CF diagnosis.

Methods

Children with a positive CF NBS were recruited from two sites in California. Retrospective, longitudinal, and cross‐sectional data were collected. A subset of subjects had nasal epithelial cells collected for CF transmembrane conductance regulator (CFTR) functional assessment. Multivariate logistic regression was used to assess the risk of reclassification.

Results

A total of 112 children completed the study (CF = 53, CFSPID = 59). Phenotypic characteristics between groups showed differences in pancreatic insufficiency prevalence, immunoreactive trypsinogen (IRT) levels, and Pseudomonas aeruginosa (PSA) colonization. Spirometry measures were not different between groups. Nasal epithelial cells from 10 subjects showed 7%–30% of wild‐type (WT)‐CFTR (wtCFTR) function in those who reclassified and 27%–67% of wtCFTR function in those who retained the CFSPID designation. Modeling revealed that increasing sweat chloride concentration (sw[Cl−]) and PSA colonization were independent risk factors for reclassification to CF.

Conclusion

Increasing sw[Cl−] and a history of PSA colonization are associated with the risk of reclassification from CFSPID to CF in a population with high IRT and two CFTR variants. A close follow‐up to monitor phenotypic changes remains critical in this population. The role of CFTR functional assays in this population requires further exploration.
Autocrine EGF and TGF‐α promote primary and acquired resistance to ALK/c‐Met kinase inhibitors in non‐small‐cell lung cancer
Authors: Wang Yueqin , Zhang Yu , Chen Ruiying , Tian Xin
Published: December 2022

Drug resistance severely limits the clinical therapeutic value of molecularly targeted drugs. Growth factors gain a tremendous amount of focus due to the ability to promote drug resistance in non‐small‐cell lung cancer (NSCLC). However, whether tumor cells themselves can mediate drug resistance by secreting growth factors needs further clarification. Here, we first screened growth factors to identify autocrine epidermal growth factor (EGF) and transforming growth factor alpha (TGF‐α) that caused primary resistance to the ALK inhibitor TAE684 in H3122 cells and the c‐MET‐specific inhibitor SGX‐523 in EBC‐1 cells. Next, we discovered increased autocrine production of EGF and TGF‐α in established acquired resistant H3122/TR and EBC‐1/SR cells. Importantly, overexpression of EGF and TGF‐α in two NSCLC cell lines produced resistance to TAE684 and SGX‐523. Clinically, NSCLC patients with high expression of EGF and TGF‐α developed primary resistance to crizotinib. Mechanistically, autocrine EGF and TGF‐α activated EGFR signaling pathways to survive targeted c‐Met and ALK inhibition. Furthermore, combined treatment with gefitinib circumvented EGF‐ and TGF‐α‐mediated primary and acquired resistance to TAE684/SGX‐523. Taken together, these results suggested increased autocrine EGF and TGF‐α conferred primary and acquired resistance to ALK/c‐Met kinase inhibitors in NSCLC.
A Robust Switchable Oil‐In‐Water Emulsion Stabilized by Electrostatic Repulsions between Surfactant and Similarly Charged Carbon Dots
Authors: Abbas Ansar , Zhang Chen , Hussain Sameer , Li Yang , Gao Ruixia , Li Jing , Liu Xueyi , Zhang Minghui , Xu Silong
Published: December 2022

How to control the stability of oil‐in‐water (O/W) emulsions is one of the main topics for scientists working in colloidal systems. Recently, carbon dots (CDs) have received great interest as smart materials because of their excellent physicochemical properties and versatile applications. Herein, for the first time, advanced and switchable O/W emulsions are presented that are stabilized by the synergistic effect of cationic surfactant cetyltrimethylammonium bromide CTAB (emulsifier) and similarly charged CDs (stabilizer). In the formulated emulsion, the cationic surfactant molecules are adsorbed at the oil and water interface to decrease the interfacial tension and enrich the drops with a positive charge to ensure intensive electrostatic repulsions among them. On the contrary, cationic CDs are distributed in the water phase among the droplets to reduce the water secretion and prevent flocculation and droplet coalescence. The stabilizing effect is found to be universal for emulsions of a range of oil phases. Furthermore, the formulated emulsion is found to be switchable between “stable” and “unstable” modes by adding an equivalent of anionic surfactant sodium dodecyl benzene sulphonate (SDBS). The stabilized and switchable O/W emulsions are believed to have wide practical applications in water purification, pharmaceuticals, protein recognition, as well as catalysis.
Influence of Initial Structures on the Mechanical Properties in Cold‐Rolled Transformation‐Induced Plasticity Steel
Authors: Ni Shenya , Li Jiayu , Wang Yu , Wang Kaitai , Xu Bin
Published: December 2022

A novel transformation‐induced plasticity steel is analyzed to study the effects of initial structures and the intercritical annealing temperatures on austenization behavior, strain distribution, and the characteristics of retained austenite (RA). The resulting microstructure and its relationship with mechanical properties are measured using dilatometry, scanning electron microscopy, electron backscatter diffraction, X‐ray diffraction, and tensile testing. The results show that the initial structure is composed of martensite (M) or tempered martensite (TM) and can significantly refine the final microstructure and its strain distribution is more homogeneous compared to the ferrite + perlite (F + P) initial structure samples. However, it is found that the larger size of the RA mainly distributes at the ferrite grain boundaries while the smaller size mainly distributes in the bainite matrix and outside martensite. Meanwhile, most of the RA in the bainite matrix are films and the carbon concentration is high. In addition, the initial M samples have many homogeneous lath interfaces and the ferrite has a strong carbon discharge ability during high‐temperature annealing, so the fraction of RA is the highest at 23.1% when annealed at 820 °C, and the corresponding carbon concentration is 1.16 wt%, so the final combination of strength and ductility is up to 32.1 GPa%.
Catalytic degradation of toxic organic dye using an aluminum‐doped Cu0.4Zn0.6‐xAlxFe2O4 (x = 0.0, 0.2, 0.4, 0.6) spinel ferrite in a photo‐Fenton system
Authors: Akhter Morsheda , Dutta Sagar Kumar , Dhar Palash Kumar , Ahmed Jamil , Khan Mohammed Nazrul Islam , Amin Md. Khairul , Islam Jahidul
Published: December 2022

Catalytic activity of spinel ferrite in breaking down toxic dye materials are promising due to their uniqueness. In this study, aluminum‐doped copper zinc ferrite, Cu0.4Zn0.6‐xAlxFe2O4 (x = 0.0, 0.2, 0.4, 0.6), a catalyst for toxic dye degradation is synthesized through chemical co‐precipitation route. The formation of the spinel ferrite catalyst is initially confirmed by Fourier transform infrared spectra, which shows the frequency of metal‐oxygen bond vibration at 539 and 427 cm−1 attributed to the tetrahedral and octahedral sites respectively. Higher intensity sharp peak of X‐ray diffraction for (311) plane is the evidence for the phase purity and the formation of spinel ferrite. The crystallite size is found to decrease with the increase of Al3+ ion. The surface structure of the obtained particles is investigated using a scanning electron microscope. Analyses of the material's magnetic characteristics using a vibrating sample magnetometer (VSM) revealed that it is, in fact, a soft magnet, as evidenced by the loop of its hysteresis, which is narrow. The catalytic degradation of methylene blue dye under the mechanism of the photo‐Fenton process is studied with the obtained spinel ferrites and the result is found to be as high as 96.5%. The process follows pseudo‐second order kinetics and the Langmuir isotherm.
The Fragility of the School-in-Pandemic in Chile
Authors: Bellei Cristián , Contreras Mariana , Ponce Tania , Yañez Isabel , Díaz Rocío , Vielma Constanza
Published: December 2022

This chapter examines how Chilean education was affected by the COVID-19 pandemic in 2020. Like all school systems worldwide, Chilean education was strongly impacted, with schools closing for nearly the entire academic year, which necessitated an improvised “distance education.” This new system faced enormous difficulties, especially in rural sectors and for families that lacked sufficient resources in their homes, which in the case of Chile represent a significant portion of the population. Based on secondary sources and a study conducted by the authors, this chapter begins by describing the fundamental characteristics of Chilean education before continuing with an overview of the principal actions undertaken by public authorities to confront the pandemic in the educational sphere; we then present the (scant) information available on how the suspension of in-person classes affected different school actors and summarize the basic findings of our own study on this topic, whose focus is educational experiences at home. The chapter concludes with some reflections of a more general nature that seek to situate the educational debate triggered by the pandemic in a broader context, concerning the future evolution of the education system.
Introducing and solving generalized Black–Scholes PDEs through the use of functional calculus
Authors: Oliva-Maza Jesús , Warma Mahamadi
Published: December 2022

We introduce some families of generalized Black–Scholes equations which involve the Riemann–Liouville and Weyl space-fractional derivatives. We prove that these generalized Black–Scholes equations are well-posed in$$(L^1-L^\infty )$$(L1-L∞)-interpolation spaces. More precisely, we show that the elliptic-type operators involved in these equations generate holomorphic semigroups. Then, we give explicit integral expressions for the associated solutions. In the way to obtain well-posedness, we prove a new connection between bisectorial-like operators and sectorial operators in an abstract setting. Such a connection extends the scaling property of sectorial operators to a wider family of both operators and the functions involved.
Ergodic decompositions of Dirichlet forms under order isomorphisms
Authors: Dello Schiavo Lorenzo , Wirth Melchior
Published: December 2022

We study ergodic decompositions of Dirichlet spaces under intertwining via unitary order isomorphisms. We show that the ergodic decomposition of a quasi-regular Dirichlet space is unique up to a unique isomorphism of the indexing space. Furthermore, every unitary order isomorphism intertwining two quasi-regular Dirichlet spaces is decomposable over their ergodic decompositions up to conjugation via an isomorphism of the corresponding indexing spaces.