bluuebunny/crossref_metadata_2025 huggingface dataset:
Design, imaging and performance of 3D printed open‐cell architectures for porous electrodes: quantification of surface area and permeability
Authors: Kaishubayeva Nazira , Ponce de León Carlos , Walsh Frank C , Arenas Luis F
Published: April 2021

BACKGROUND

The development of new open‐cell porous electrodes for electrochemical flow cells and reactors is demonstrated through the application of 3D printing. The properties of diverse architectures were investigated, including rectangular, circular, hexagonal and triangular cells with linear porosity grades of 10, 20 and 30 pores per inch (ppi). Specimens were digitally designed, then 3D printed in stainless steel via selective laser melting. After being examined using scanning electron microscopy, they were characterized in terms of volumetric surface area and porosity with the aid of X‐ray computed tomography. Pressure drop measurements were performed over a range of mean linear velocity and Reynolds number, allowing the estimation of Darcy's friction factor and permeability.

RESULTS

Volumetric surface area estimated from tomography scans was ≤36% higher than the nominal values owing to surface roughness and post‐processing algorithms. By contrast, volumetric porosity obtained by tomography agreed fully with measured values. Triangular architectures afforded additional surface area both digitally and according to tomography. The largest pressure drop was found in circular materials, the triangular ones showing the lowest. The 20 ppi triangular architecture had a volumetric surface area of ≈44.5 cm−1 and a permeability of 2.31 × 10−5 cm2.

CONCLUSION

Triangular architectures were preferred as a consequence of their favourable combination of high surface area and high permeability with low mass and reduced digital complexity. This provides a strategy to initiate the optimization of 3D printed porous electrodes for electrochemical flow cells and reactors in novel and niche applications. © 2021 The Authors. Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI).
PVP‐assisted synthesis of P‐Bi4O5Br2/AgI heterojunction with enhanced photocatalytic activity for degradation of rhodamine B
Authors: Luo Shizi , Xiao Xinyan , Wang Yi , Lu Mingli
Published: April 2021

BACKGROUND

The commonly used RhB dye is a carcinogen that is widely found in environmental matrices and poses a threat to aquatic biota and human health. However, conventional wastewater treatment processes do not effectively remove low concentrations of these pollutants. Herein, the P‐Bi4O5Br2/AgI (PBA) heterojunction was synthesized via a polyvinylpyrrolidone (PVP)‐assisted solvothermal and precipitation method in this work.

RESULTS

The photocatalytic efficiency of the PBA heterojunction was evaluated by degrading rhodamine B (RhB) with the irradiation of simulated sunlight. P‐Bi4O5Br2/AgI‐50 (PBA‐50, the mass fraction of AgI in the composite was 50%) composite could degrade 98% RhB under 90 min irradiation of 500 W Xenon lamp, and its pseudo first‐order reaction rate constant was 0.04265 min−1, which was 17.1, 2.16, and 2.94 times higher than that of Bi4O5Br2, P‐Bi4O5Br2, and AgI, respectively. Besides, the effects of the dosage of photocatalyst and the anion on the photocatalytic degradation of RhB over PBA‐50 were analyzed.

CONCLUSION

The enhanced photocatalytic activity of PBA was attributed to its better visible light capture ability, larger specific surface area, and faster photogenerated carrier separation efficiency, all of which were confirmed by scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET), UV‐Vis diffues reflectance spectroscopy (DRS), X‐ray photoelectron spectroscopy (XPS), and photoelectrochemical analysis. In addition, the free radical trapping experiments confirmed that ·O2− and h+ were the main active species for degradation of RhB. Additionally, the smaller bandgap and the more negative conduction band position of Bi4O5Br2 were reached after the introduction of PVP. Accordingly, a possible type‐II heterojunction photocatalytic mechanism of P‐Bi4O5Br2/AgI was proposed. © 2021 Society of Chemical Industry (SCI).
“I just keep quiet about it and act as if everything is alright” – The cascade from trauma to disengagement among adolescents living with HIV in western Kenya
Authors: Enane Leslie A , Apondi Edith , Omollo Mark , Toromo Judith J , Bakari Salim , Aluoch Josephine , Morris Clemette , Kantor Rami , Braitstein Paula , Fortenberry J Dennis , Nyandiko Winstone M , Wools‐Kaloustian Kara , Elul Batya , Vreeman Rachel C
Published: April 2021

Introduction

There are approximately 1.7 million adolescents living with HIV (ALHIV, ages 10 to 19) globally, including 110,000 in Kenya. While ALHIV experience poor retention in care, limited data exist on factors underlying disengagement. We investigated the burden of trauma among disengaged ALHIV in western Kenya, and its potential role in HIV care disengagement.

Methods

We performed in‐depth qualitative interviews with ALHIV who had disengaged from care at two sites, their caregivers and healthcare workers (HCW) at 10 sites, from 2018 to 2020. Disengagement was defined as not attending clinic ≥60 days past a missed scheduled visit. ALHIV and their caregivers were traced through phone calls and home visits. Interviews ascertained barriers and facilitators to adolescent retention in HIV care. Dedicated questions elicited narratives surrounding traumatic experiences, and the ways in which these did or did not impact retention in care. Through thematic analysis, a conceptual model emerged for a cascade from adolescent experience of trauma to disengagement from HIV care.

Results

Interviews were conducted with 42 disengaged ALHIV, 34 caregivers and 28 HCW. ALHIV experienced a high burden of trauma from a range of stressors, including experiences at HIV disclosure or diagnosis, the loss of parents, enacted stigma and physical or sexual violence. A confluence of factors – trauma, stigma and isolation, and lack of social support – led to hopelessness and depression. These factors compounded each other, and resulted in complex mental health burdens, poor antiretroviral adherence and care disengagement. HCW approaches aligned with the factors in this model, suggesting that these areas represent targets for intervention and provision of trauma‐informed care.

Conclusions

Trauma is a major factor underlying disengagement from HIV care among Kenyan adolescents. We describe a cascade of factors representing areas for intervention to support mental health and retention in HIV care. These include not only the provision of mental healthcare, but also preventing or addressing violence, trauma and stigma, and reinforcing social and familial support surrounding vulnerable adolescents. In this conceptualization, supporting retention in HIV care requires a trauma‐informed approach, both in the individualized care of ALHIV and in the development of strategies and policies to support adolescent health outcomes.
Weight gain before and after switch from TDF to TAF in a U.S. cohort study
Authors: Mallon Patrick WG , Brunet Laurence , Hsu Ricky K , Fusco Jennifer S , Mounzer Karam C , Prajapati Girish , Beyer Andrew P , Wohlfeiler Michael B , Fusco Gregory P
Published: April 2021

Introduction

Although weight gain has been reported with the use of integrase strand transfer inhibitors (InSTI), concurrent use of tenofovir alafenamide (TAF) has been implicated in recent studies. This study examined weight changes in people living with HIV (PLWH) who switched from tenofovir disoproxil fumarate (TDF) to TAF, to clarify the relative contribution to weight gain of core agents versus TDF to TAF switch.

Methods

Antiretroviral‐experienced, virologically suppressed PLWH in the U.S. OPERA cohort were included if they switched from TDF to TAF (5NOV2015‐28FEB2019) and either maintained all other antiretrovirals or switched from a non‐InSTI to an InSTI. Linear mixed models were used to assess weight changes before/after the switch to TAF (restricted cubic splines on time) and rates of change over time (linear splines on time, based on the shape of the weight change curves). Changes in weight on TDF or TAF were assessed among those who maintained other antiretrovirals (overall, by core class), and those who maintained an InSTI or switched to an InSTI (by core agent). All models were adjusted for age, sex, race, (age‐sex, race‐sex interactions), BMI, CD4 cell count, endocrine disorders and concurrent medications that could affect weight.

Results

A total of 6908 PLWH were included, with 5479 maintaining all other antiretrovirals (boosted protease inhibitor: 746, non‐nucleoside reverse transcriptase inhibitor: 1452, InSTI: 3281) and 1429 switching from a non‐InSTI to an InSTI (elvitegravir/cobicistat: 1120, dolutegravir: 174, bictegravir: 129). In adjusted models, modest weight gain was observed over time on TDF for most (0.24 to 0.71 kg/year); raltegravir was the exception with weight loss. Switching to TAF was associated with early, pronounced weight gain for all (1.80 to 4.47 kg/year). This effect with TAF switch was observed both in PLWH maintaining other antiretrovirals and those switching to an InSTI, regardless of which InSTI agent was used. Weight gain tended to slow down or plateau approximately nine months after switch to TAF.

Conclusions

In this large, diverse U.S. cohort of PLWH, switching from TDF to TAF was associated with pronounced weight gain immediately after switch, regardless of the core class or core agent, suggesting an independent effect of TAF on weight gain.
The first Japanese family of CDH3‐related hypotrichosis with juvenile macular dystrophy
Authors: Hayashi Takaaki , Katagiri Satoshi , Kubota Daiki , Mizobuchi Kei , Ishiuji Yozo , Asahina Akihiko , Kameya Shuhei , Nakano Tadashi
Published: April 2021

Background

Hypotrichosis with juvenile macular dystrophy (HJMD) is a rare autosomal recessive inherited disorder caused by biallelic variants in the CDH3 gene encoding P‐cadherin. Here, we report two Japanese sibling patients with HJMD.

Methods

Whole‐exome sequencing (WES) was performed to identify disease‐causing variants. In addition, ophthalmic and dermatological examinations were performed to classify the phenotype of each patient.

Results

The WES analysis revealed novel compound heterozygous CDH3 variants [c.123_129dupAGGCGCG (p.Glu44fsX26) and c.2280+1G>T] in both patients; the unaffected, nonconsanguineous parents each exhibited one of the variants. Both patients showed the same clinical findings. Ophthalmologically, they exhibited progressive loss of visual acuity and chorioretinal macular atrophy, as examined with fundoscopy, fundus autofluorescence imaging, and optical coherence tomography. Full‐field electroretinography, assessing generalized retinal function, revealed nearly normal amplitudes of both rod‐ and cone‐mediated responses. Multifocal electroretinography, reflecting macular function, showed extremely decreased responses in the central area, corresponding to the chorioretinal atrophy. Dermatological examination revealed diffuse thinning of the scalp hair, which was sparse and fragile.

Conclusion

This is the first report of Japanese patients with HJMD and novel compound heterozygous truncating variants in CDH3. Our findings can expand the knowledge and understanding of CDH3‐related HJMD, which could be helpful to ophthalmologists and dermatologists.
Null controllability of degenerate parabolic equation with memory
Authors: Allal Brahim , Fragnelli Genni
Published: April 2021

In this paper, we analyze the null controllability property for a degenerate parabolic equation involving memory terms with a locally distributed control. We first derive a null controllability result for a nonhomogeneous degenerate heat equation via new Carleman estimates with weighted time functions that do not blow up at
. Then, this result is successfully used with a classical fixed point to obtain null controllability for the initial memory system.
Mental health, well‐being, and help‐seeking in schools among black adolescents: The role of discrimination in high‐achieving academic settings
Authors: Goodwin Aijah K. B. , Chen Grace L. , Long Anna C. J.
Published: April 2021

The underrepresentation of Black youth in high‐achieving academic settings places significant importance on examining their daily experiences. This study investigated the relationship between school discrimination, well‐being in academic settings, the risk for anxiety and depression, and school mental health help‐seeking intentions. Participants included 110 Black high school students (66% women; mean age = 15.67) attending a special‐admissions public school who participated in their school universal mental health screening. Black high school students in this high achieving context experienced few occurrences of school discrimination, yet these experiences still significantly impacted their internalizing severity. The mediation analyses revealed that experiences of discrimination predicted lower levels of academic efficacy and school connectedness, which predicted higher levels of internalizing symptoms. Experiences of discrimination were not related to mental health help‐seeking at school. However, Black youth's intentions to seek mental health services at school were low, regardless of discriminatory experiences, as evidenced by the percentage of universal screening dissent and their self‐reported plans to seek support. The findings highlight the need to consider Black adolescents' experiences in high achieving schools when engaged in universal mental health screening and individual and school‐wide mental health prevention efforts.
Dynamically probing ATP‐dependent RNA helicase A‐assisted RNA structure conversion using single molecule fluorescence resonance energy transfer
Authors: Wu Chengcheng , Shan Yanke , Wang Shouyu , Liu Fei
Published: April 2021

RNA helicase A (RHA) as a member of DExH‐box subgroup of helicase superfamily II, participates in diverse biological processes involved in RNA metabolism in organisms, and these RNA‐mediated biological processes rely on RNA structure conversion. However, how RHA regulate the RNA structure conversion was still unknown. In order to unveil the mechanism of RNA structure conversion mediated by RHA, single molecule fluorescence resonance energy transfer was adopted to in our assay, and substrates RNA were from internal ribosome entry site of foot‐and‐mouth disease virus genome. We first found that the RNA structure conversion by RHA against thermodynamic equilibrium in vitro, and the process of dsRNA YZ converted to dsRNA XY through a tripartite intermediate state. In addition, the rate of the RNA structure conversion and the distribution of dsRNA YZ and XY were affected by ATP concentrations. Our study provides real‐time insight into ATP‐dependent RHA‐assisted RNA structure conversion at the single molecule level, the mechanism displayed by RHA may help in understand how RHA contributes to many biological functions, and the basic mechanistic features illustrated in our work also underlay more complex protein‐assisted RNA structure conversions.
CRISPR/Cas9‐mediated knockout of LW‐opsin reduces the efficiency of phototaxis in the diamondback moth Plutella xylostella
Authors: Chen Shao‐Ping , Liu Zhao‐Xia , Chen Yan‐Ting , Wang Yue , Chen Jin‐Zhi , Fu Shu , Ma Wei‐Feng , Xia Shuang , Liu Dan , Wu Tong , Yang Guang
Published: April 2021

BACKGROUND

Opsins are crucial for animal vision. The identity and function of opsins in Plutella xylostella remain unknown. The aim of the research is to confirm which opsin gene(s) contribute to phototaxis of P. xylostella.

RESULTS

LW‐opsin, BL‐opsin and UV‐opsin, were identified in the P. xylostella genome. LW‐opsin was more highly expressed than the other two opsin genes, and all three genes were specifically expressed in the head. Three P. xylostella strains, LW‐13 with a 13‐bp deletion in LW‐opsin, BL + 2 with a 2‐bp insertion in BL‐opsin, and UV‐29 with a 5‐bp insertion and a 34‐bp deletion in UV‐opsin, were established from the strain G88 using the CRISPR/Cas9 system. Among the three opsin‐knockout strains, only male and female LW‐13 exhibited weaker phototaxis to lights of different wavelengths and white light than G88 at 2.5 lx due to defective locomotion, and LW‐13 was defective to sense white, green and infrared lights. The locomotion of LW‐13 was reduced compared with G88 at 2.5, 10, 20, 60, 80, 100, and 200 lx under the green light, but the locomotion of LW‐13 female was recovered at 80, 100 and 200 lx. The defective phototaxis to the green light of male LW‐13 was not affected by light intensity, while the defective phototaxis to the green light of female LW‐13 was recovered at 10, 20, 60, 80, 100, and 200 lx.

CONCLUSION

LW‐opsin is involved in light sensing and locomotion of P. xylostella, providing a potential target gene for controlling the pest. © 2021 Society of Chemical Industry.
Hollow electrode capillary plasma ionization source for rapid online detection of gaseous samples
Authors: Xu Wen , Shen Zeyue , Zhang Junliang , Zhang Tengyu , Wu Huanming , Wang Chenlu , Yu Jiancheng , Tang Keqi
Published: April 2021

RATIONALE

Gas chromatography mass spectrometry (GC‐MS) with electron ionization (EI) is the most widely used analysis technique of gaseous samples, but it may be time‐consuming for online monitoring of mixtures whose concentrations relatively change rapidly. On the contrary, current ionization methods, such as chemical ionization (CI) and proton transfer reaction (PTR), also have some disadvantages such as selectivity. Therefore, appropriate soft ionization sources are searched for rapid online detection.

METHODS

Hollow electrode capillary plasma ionization (HECPI) is based on single electrode plasma. A hollow capillary was placed as both the electrode and the inlet of the gaseous samples. The ionization source is coupled with a mass spectrometer for performance evaluation.

RESULTS

Several typical compounds have been tested with HECPI‐mass spectrometer. In this process, the dominant ion peaks of all compounds can be indexed as molecular ion peaks, and the product ions of HECPI are less than that of dielectric barrier discharge ionization (DBDI). Three gaseous samples (linalool, triethylamine, and styrene) with various concentrations have been used to further confirm the performance of this source, and the detection limit of linalool is as low as 10 ppb.

CONCLUSIONS

HECPI is simple in structure and shows good performance. The results also show that HECPI has the potential to be an effective tool for detecting online gaseous samples rapidly.
A robotic system for spine surgery positioning and pedicle screw placement
Authors: Zhang Jian , Li Weishi , Hu Lei , Yu Zhao  , Wang Tianmiao
Published: April 2021

Background

In recent years, surgeons have explored minimally invasive methods of percutaneous pedicle screw implantation which can effectively reduce human injuries. This article presents an accurate and efficient positioning method and robot system for percutaneous needle placement under c‐arm fluoroscopy.

Methods

A simple five degree of freedom (DOF) robot with a unique end‐effector is designed to perform perspective calibration and image space registration. The principle of pedicle standard axis positioning is adopted to make the axis of the pedicle overlap with the x‐ray axis of c‐arm.

Results

Then the clinical operation is carried out to verify the clinical feasibility of the designed robot and positioning method. The experimental results show that a total of 26 pedicle screws were accurately implanted. The accuracy of Grade A is 96.15%. The positioning time of a single guide pin is about 154.77 s, and three x‐ray films need to be taken on average.

Conclusions

The positioning accuracy is increased by using the present method. In addition, this method is simple in operation, short in operation time, low in X‐ray exposure.
Better precision of a new robotically assisted system for total knee arthroplasty compared to conventional techniques: A sawbone model study
Authors: Li Zheng , Chen Xin , Zhang Xiaofeng , Yan Jun , Song Youdong , Huo Yujia , Lin Jin
Published: April 2021

Background

The purpose of this study was to compare the accuracy of this new HURWA robotic‐assisted total knee arthroplasty (TKA) technique to the accuracy of the conventional technique in a sawbone model.

Methods

The HURWA robotic‐assisted TKA system was applied in the robotic group. After bone resection, all of these sawbones were scanned by the use of a structured light scanning system. Measurements of bone resections, femoral coronal and sagittal measurements, and tibial coronal and sagittal measurements were recorded.

Results

Compared to the conventional technique, the HURWA robotic‐assisted system significantly improved the accuracy of the bone resection levels and angles. In the robotic group, the accuracy of all of the bone resection levels was below 0.6 mm (with standard deviation [SD] below 0.6 mm), and all of the bone resection angles were below 0.6° (with SD below 0.4°).

Conclusion

Our data suggest that this novel HURWA robotic‐assisted system can significantly improve the accuracy of bone resection levels and angles.
In Vitro Anticancer and In Silico Studies of Some 1,4‐Benzoxazine‐1,2,4‐oxadiazole Hybrids
Authors: Nagaraju Ashwini , Kumar Nukala Satheesh , Narasimha Swamy Thirukovela T. , Manchal Ravinder
Published: April 2021

The one‐pot synthesis of some new 1,4‐benzoxazine‐1,2,4‐oxadiazole hybrids (4 a–4 n) through the reaction between 3‐(3‐oxo‐2H‐benzo[b][1,4]oxazin‐4(3H)‐yl)propanenitrile and several aromatic carboxylicacids was reported herein. Five of them showed promising in vitro anticaner activity over A549 (lung), PC3 (prostate), HeLa (cervical) and MCF‐7 (breast) when compared with Etoposide. Predominantly, the compound 4 g has shown most promisng activity against A549, PC3, HeLa and MCF‐7 with IC50 values of 3.98, 3.41, 6.82 and 3.82 μM respectively. In addition, in silico studies of derivatives (4 a–n) on EGFR receptor recommended that the more potent compound 4 g strongly binds to protein EGFR (pdb id : 4HJO).
Alumina‐Supported Alkali and Alkaline Earth Metal‐Based Catalyst for Selective Decarboxylation of Itaconic Acid to Methacrylic Acid
Authors: Ali Hadi , Kansal Sushil Kumar , Saravanamurugan Shunmugavel
Published: April 2021

The present study focuses on selective decarboxylation of itaconic acid (IA) to methacrylic acid (MAA) using alkali and alkaline earth metals (Na, K, Mg and Ca) supported on Al2O3, prepared by incipient wet impregnation approach. The parent Al2O3, predominantly composed of the boehmite phase, is entirely transformed to γ‐Al2O3 phase upon impregnating calcium, based on XRD analysis, and this is not the case for other metals employed in this study. FTIR analysis corroborates the complete decomposition of nitrate precursor in the case of calcium than other metals (Na, K and Mg). UV‐Vis analysis using diffused reflectance mode suggests that Ca incorporated on to the Al2O3 matrix. Among the catalysts employed, the highest yield of methacrylic acid (MAA) (46.7 %) is achieved with 5 wt % Ca/Al2O3 at 250 °C, 20 bar N2 after 3 h. Moreover, 15.1 % of α‐hydroxyisobutyric acid (α‐HIBA), a hydrated product of MAA, is also obtained, and thus, the combined yield of MAA and α‐HIBA is 61.8 %. The selective decarboxylation of IA to MAA/α‐HIBA can be correlated with the number of basic sites present in the 5 wt % Ca/Al2O3, which possess the highest number of basic sites than other catalysts.
TfOH/DMEDA‐Mediated Cyclization of 2‐(3‐Arylthioureido)‐amide to Form 2‐Thioimidazoline‐4‐ones
Authors: An Guanghui , Liu Jianhui
Published: April 2021

A synthetic methodology for a series of 2‐thioimidazoline‐4‐ones (4 a–4 u) was developed using trifluoromethanesulfonic acid (TfOH)/N,N′‐dimethylethylenediamines (DMEDA) in dichloromethane. α‐Aminoacetamides and isothiocyanates were used to prepare 2‐(3‐arylthiourea)amide (3 a–3 u), which was cyclized to produce the desired 2‐thioimidazoline‐4‐ones with good to excellent yield (75 %‐95 %). All the new compounds obtained were characterized by 1H NMR, 13C NMR and HRMS, and further corroborated by X‐ray crystallography for 4 i, 4 o, 4 p.
Bifunctional Self‐Powered Drug Delivery System to Promote the Release and Transdermal Delivery of Polar Molecules
Authors: Ma Zequn , Zhang Yi , Zhang Yihe , An Qi , Dong Hong , Fu Han , Zhang Hui , Zhang Shuting , Tong Wangshu
Published: April 2021

Electrical stimulation to enhance molecular release and transdermal drug delivery has aroused extensive research and clinical medical interest owing to its unique advantages such as being stimuli‐responsive, sensitive, flexible, and controllable. Herein, a self‐powered system driven by piezoelectric substrate is designed to promote the release and transdermal delivery of polar molecules. Notedly, the electric signals generated by piezoelectric substrate contribute to trigger the electric‐responsive drug release and transdermal drug delivery. In addition, the system can be considered as a layer‐by‐layer drug depot with mesoporous silica particles assembled on a piezoelectric flexible composite film, through which the electric signals can be gathered and stored from biomechanical energy. As a result, the ginsenoside Rb1, a representative polar Chinese medicine molecule, can be facilely released from the integrated device in response to finger press. Importantly, the amount of penetration through skin tissues and cells was significantly increased under mechanical stimuli, and the cell bioactivity results manifested that the system also supported high cell viabilities. The integrated device is anticipated to achieving high efficiency in drug release and transdermal delivery via acting as a transdermal patch in the field of biomedicine.
Trauma exposure and the PTSD symptoms of college teachers during the peak of the COVID‐19 outbreak
Authors: Fan Changyu , Fu Ping , Li Xueyan , Li Min , Zhu Miao
Published: April 2021

This study aimed to explore influencing factors for the psychological impact of coronavirus disease 2019 (COVID‐19) on Wuhan college teachers, posttraumatic stress symptoms in particular, so as to inform evidence‐based strategy development to ameliorate such adverse impacts. An online survey was conducted from 26 to 29 April 2020, and 1650 teachers (47.54% male; M = 40.28 years, SD = 8.3 years) enrolled in Wuhan universities and colleges participated. The results showed that the overall incidence of posttraumatic stress disorder (PTSD) among college teachers was as high as 24.55%, but the average level of PTSD score was low (M = 1.06, SD = 0.72). Logistic regression analysis showed that for those with confirmed COVID‐19, the ratio was much higher, up to 2.814 (95% confidence interval [CI]: [1.542, 5.136], p < 0.001); that is, compared with those without symptoms, the ratio of PTSD increased by 181%. For those who had family members or relatives who died of COVID‐19, the ratio was 5.592 (95% CI: [2.271, 13.766], p < 0.001), 459% higher than those who had no one who died. But the living places during the pandemic had no significant effect on PTSD. The findings suggest that mental health services reducing PTSD should be provided. Teachers who confirmed COVID‐19 or lost loved ones to COVID‐19 should be given particular care.
Predictive Value of Folate Receptor‐Positive Circulating Tumor Cells for the Preoperative Diagnosis of Lymph Node Metastasis in Patients with Lung Adenocarcinoma
Authors: Li Zhao , Xu Ke , Xu Lekai , Dai Jie , Jin Kaiqi , Zhu Yuming , Yang Yang , Jiang Gening
Published: April 2021

Noninvasive assessments of the risk of lymph node metastasis (LNM) in patients with lung adenocarcinoma (LAD) are of great value for selecting individualized treatment options. However, the diagnostic accuracies of different preoperative LN evaluation methods in routine clinical practice are not satisfactory. Here, an assessment to detect folate receptor (FR)‐positive circulating tumor cells (CTCs) based on ligand‐targeted enzyme‐linked polymerization is established. FR‐positive CTCs have the potential to improve the specificity and sensitivity of diagnosing LNM in lung cancer patients. The addition of CTC level improved the diagnostic efficiency of the initial prediction model that comprises other clinical parameters. A nomogram for predicting preoperative LNM is established, which showed good prediction and calibration capacities and achieved an average area under the curve of 0.786. Good correlations are observed between the CTC level and nodal classifications, such as the number of positive LNs and the ratio of the number of positive LNs to removed LNs (LN ratio or LNR). The ligand‐targeted enzyme‐linked polymerization‐assisted assessment of CTCs enables noninvasive detection and has a useful predictive value for the preoperative diagnosis of LNM in patients with LAD.
Light Higgs searches in $$ t\overline{t}\phi $$ production at the LHC
Authors: Azevedo Duarte , Capucha Rodrigo , Gouveia Emanuel , Onofre António , Santos Rui
Published: April 2021

Abstract

In this paper we propose a new reconstruction method to explore the low mass region in the associated production of top-quark pairs ($$ t\overline{t} $$
t

t
¯

) with a generic scalar boson (ϕ) at the LHC. The new method of mass reconstruction shows an improved resolution of at least a factor of two in the low mass region when compared to previous methods, without the loss of sensitivity of previous analyses. It turns out that it also leads to an improvement of the mass reconstruction of the 125 GeV Higgs for the same production process. We use an effective Lagrangian to describe a scalar with a generic Yukawa coupling to the top quarks. A full phenomenological analysis was performed, using Standard Model background and signal events generated with MadGraph5_aMC@NLO and reconstructed using a kinematic fit. The use of CP-sensitive variables allows then to maximize the distinction between CP-even and CP-odd components of the Yukawa couplings. Confidence Levels (CLs) for the exclusion of ϕ bosons with mixed CP (both CP-even and CP-odd components) were determined as a function of the top Yukawa couplings to the ϕ boson. The mass range analysed starts slightly above the ϒΥ mass up to 40 GeV, although the analysis can be used for an arbitrary mass. If no new light scalar is found, exclusion limits at 95% CL for the absolute value of the CP-even and CP-odd Yukawa are derived. Finally, we analyse how these limits constrain the parameter space of the complex two-Higgs doublet model (C2HDM).
Comments on magnetic black holes
Authors: Maldacena Juan
Published: April 2021

Abstract

We discuss aspects of magnetically charged black holes in the Standard Model. For a range of charges, we argue that the electroweak symmetry is restored in the near horizon region. The extent of this phase can be macroscopic. If Q is the integer magnetic charge, the fermions lead to order Q massless two dimensional fermions moving along the magnetic field lines. These greatly enhance Hawking radiation effects.
Do all 5d SCFTs descend from 6d SCFTs?
Authors: Bhardwaj Lakshya
Published: April 2021

Abstract

We present examples of 5d SCFTs that serve as counter-examples to a recently actively studied conjecture according to which it should be possible to obtain all 5d SCFTs by integrating out BPS particles from 6d SCFTs compactified on a circle. We further observe that it is possible to obtain these 5d SCFTs from 6d SCFTs if one allows integrating out BPS strings as well. Based on this observation, we propose a revised version of the conjecture according to which it should be possible to obtain all 5d SCFTs by integrating out both BPS particles and BPS strings from 6d SCFTs compactified on a circle. We describe a general procedure to integrate out BPS strings from a 5d theory once a geometric description of the 5d theory is given. We also discuss the consequences of the revised conjecture for the classification program of 5d SCFTs.
Two-meson form factors in unitarized chiral perturbation theory
Authors: Shi Yu-Ji , Seng Chien-Yeah , Guo Feng-Kun , Kubis Bastian , Meißner Ulf-G. , Wang Wei
Published: April 2021

Abstract

We present a comprehensive analysis of form factors for two light pseudoscalar mesons induced by scalar, vector, and tensor quark operators. The theoretical framework is based on a combination of unitarized chiral perturbation theory and dispersion relations. The low-energy constants in chiral perturbation theory are fixed by a global fit to the available data of the two-meson scattering phase shifts. Each form factor derived from unitarized chiral perturbation theory is improved by iteratively applying a dispersion relation. This study updates the existing results in the literature and explores those that have not been systematically studied previously, in particular the two-meson tensor form factors within unitarized chiral perturbation theory. We also discuss the applications of these form factors as mandatory inputs for low-energy phenomena, such as the semi-leptonic decays Bs→ π+π−ℓ+ℓ− and the τ lepton decay τ → π−π0ντ, in searches for physics beyond the Standard Model.
The perturbative CFT optical theorem and high-energy string scattering in AdS at one loop
Authors: Antunes António , Costa Miguel S. , Hansen Tobias , Salgarkar Aaditya , Sarkar Sourav
Published: April 2021

Abstract

We derive an optical theorem for perturbative CFTs which computes the double discontinuity of conformal correlators from the single discontinuities of lower order correlators, in analogy with the optical theorem for flat space scattering amplitudes. The theorem takes a purely multiplicative form in the CFT impact parameter representation used to describe high-energy scattering in the dual AdS theory. We use this result to study four-point correlation functions that are dominated in the Regge limit by the exchange of the graviton Regge trajectory (Pomeron) in the dual theory. At one-loop the scattering is dominated by double Pomeron exchange and receives contributions from tidal excitations of the scattering states which are efficiently described by an AdS vertex function, in close analogy with the known Regge limit result for one-loop string scattering in flat space at finite string tension. We compare the flat space limit of the conformal correlator to the flat space results and thus derive constraints on the one-loop vertex function for type IIB strings in AdS and also on general spinning tree level type IIB amplitudes in AdS.
The Master Ward Identity for Scalar QED
Authors: Dütsch Michael , Peters Luis , Rehren Karl-Henning
Published: April 2021

It is emphasized that for interactions with derivative couplings, the Ward Identity (WI) securing the preservation of a global symmetry should be modified. Scalar QED is taken as an explicit example. More precisely, it is rigorously shown in scalar QED that the naive WI and the improved Ward Identity (‘Master Ward Identity’, MWI) are related to each other by a finite renormalization of the time-ordered product (‘T-product’) for the derivative fields, and we point out that the MWI has advantages over the naive WI—in particular with regard to the proof of the MWI. We show that the MWI can be fulfilled in all orders of perturbation theory by an appropriate renormalization of the T-product, without conflict with other standard renormalization conditions. Relations with other recent formulations of the MWI are established.
Noncrossing Arc Diagrams, Tamari Lattices, and Parabolic Quotients of the Symmetric Group
Authors: Mühle Henri
Published: April 2021

Ordering permutations by containment of inversion sets yields a fascinating partial order on the symmetric group: the weak order. This partial order is, among other things, a semidistributive lattice. As a consequence, every permutation has a canonical representation as a join of other permutations. Combinatorially, these canonical join representations can be modeled in terms of arc diagrams. Moreover, these arc diagrams also serve as a model to understand quotient lattices of the weak order. A particularly well-behaved quotient lattice of the weak order is the well-known Tamari lattice, which appears in many seemingly unrelated areas of mathematics. The arc diagrams representing the members of the Tamari lattices are better known as noncrossing partitions. Recently, the Tamari lattices were generalized to parabolic quotients of the symmetric group. In this article, we undertake a structural investigation of these parabolic Tamari lattices, and explain how modified arc diagrams aid the understanding of these lattices.
Significant increase in quantity and quality of knee arthroplasty related research in KSSTA over the past 15 years
Authors: Kirschbaum Stephanie , Kakzhad Thilo , Granrath Fabian , Jasina Andrzej , Oronowicz Jakub , Perka Carsten , Kopf Sebastian , Gwinner Clemens , Pumberger Matthias
Published: April 2021

Purpose

This study aimed to evaluate both publication and authorship characteristics in Knee Surgery, Sports Traumatology, Arthroscopy journal (KSSTA) regarding knee arthroplasty over the past 15 years.

Methods

PubMed was searched for articles published in KSSTA between January 1, 2006, and December 31st, 2020, utilising the search term ‘knee arthroplasty’. 1288 articles met the inclusion criteria. The articles were evaluated using the following criteria: type of article, type of study, main topic and special topic, use of patient-reported outcome scores, number of references and citations, level of evidence (LOE), number of authors, gender of the first author and continent of origin. Three time intervals were compared: 2006–2010, 2011–2015 and 2016–2020.

Results

Between 2016 and 2020, publications peaked at 670 articles (52%) compared with 465 (36%) published between 2011 and 2016 and 153 articles (12%) between 2006 and 2010. While percentage of reviews (2006–2010: 0% vs. 2011–2015: 5% vs. 2016–2020: 5%) and meta-analyses (1% vs. 6% vs. 5%) increased, fewer case reports were published (13% vs. 3% vs. 1%) (p < 0.001). Interest in navigation and computer-assisted surgery decreased, whereas interest in perioperative management, robotic and individualized surgery increased over time (p < 0.001). There was an increasing number of references [26 (2–73) vs. 30 (2–158) vs. 31 (1–143), p < 0.001] while number of citations decreased [30 (0–188) vs. 22 (0–264) vs. 6 (0–106), p < 0.001]. LOE showed no significant changes (p = 0.439). The number of authors increased between each time interval (p < 0.001), while the percentage of female authors was comparable between first and last interval (p = 0.252). Europe published significantly fewer articles over time (56% vs. 47% vs. 52%), whereas the number of articles from Asia increased (35% vs. 45% vs. 37%, p = 0.005).

Conclusion

Increasing interest in the field of knee arthroplasty-related surgery arose within the last 15 years in KSSTA. The investigated topics showed a significant trend towards the latest techniques at each time interval. With rising number of authors, the part of female first authors also increased—but not significantly. Furthermore, publishing characteristics showed an increasing number of publications from Asia and a slightly decreasing number in Europe.

Level of evidence

IV.
Quantitative Backscattered Electron Imaging of Bone Using a Thermionic or a Field Emission Electron Source
Authors: Hartmann Markus A. , Blouin Stéphane , Misof Barbara M. , Fratzl-Zelman Nadja , Roschger Paul , Berzlanovich Andrea , Gruber Gerlinde M. , Brugger Peter C. , Zwerina Jochen , Fratzl Peter
Published: April 2021

Quantitative backscattered electron imaging is an established method to map mineral content distributions in bone and to determine the bone mineralization density distribution (BMDD). The method we applied was initially validated for a scanning electron microscope (SEM) equipped with a tungsten hairpin cathode (thermionic electron emission) under strongly defined settings of SEM parameters. For several reasons, it would be interesting to migrate the technique to a SEM with a field emission electron source (FE-SEM), which, however, would require to work with different SEM parameter settings as have been validated for DSM 962. The FE-SEM has a much better spatial resolution based on an electron source size in the order of several 100 nanometers, corresponding to an about $$10^5$$

10
5

to $$10^6$$

10
6

times smaller source area compared to thermionic sources. In the present work, we compare BMDD between these two types of instruments in order to further validate the methodology. We show that a transition to higher pixel resolution (1.76, 0.88, and 0.57 μm) results in shifts of the BMDD peak and BMDD width to higher values. Further the inter-device reproducibility of the mean calcium content shows a difference of up to 1 wt% Ca, while the technical variance of each device can be reduced to $$\pm 0.17$$

±
0.17

wt% Ca. Bearing in mind that shifts in calcium levels due to diseases, e.g., high turnover osteoporosis, are often in the range of 1 wt% Ca, both the bone samples of the patients as well as the control samples have to be measured on the same SEM device. Therefore, we also constructed new reference BMDD curves for adults to be used for FE-SEM data comparison.
Gluten-degrading bacteria: availability and applications
Authors: Kõiv Viia , Tenson Tanel
Published: April 2021

Gluten is a mixture of storage proteins in wheat and occurs in smaller amounts in other cereal grains. It provides favorable structure to bakery products but unfortunately causes disease conditions with increasing prevalence. In the human gastrointestinal tract, gluten is cleaved into proline and gluten rich peptides that are not degraded further. These peptides trigger immune responses that might lead to celiac disease, wheat allergy, and non-celiac gluten sensitivity. The main treatment option is a gluten-free diet. Alternatively, using enzymes or microorganisms with gluten-degrading properties might alleviate the disease. These components can be used during food production or could be introduced into the digestive tract as food supplements. In addition, natural food from the environment is known to enrich the microbial communities in gut and natural environmental microbial communities have high potential to degrade gluten. It remains to be investigated if food and environment-induced changes in the gut microbiome could contribute to the triggering of gluten-related diseases.

Key points

• Wheat proteins, gluten, are incompletely digested in human digestive tract leading to gluten intolerance.

• The only efficient treatment of gluten intolerance is life-long gluten-free diet.

• Environmental bacteria acquired together with food could be source of gluten-degrading bacteria detoxifying undigested gluten peptides.
First time intravesically administered trifunctional antibody catumaxomab in patients with recurrent non-muscle invasive bladder cancer indicates high tolerability and local immunological activity
Authors: Ruf Peter , Bauer Hartwig W. , Schoberth Alexandra , Kellermann Claudia , Lindhofer Horst
Published: April 2021

Transurethral resection of the tumor (TUR-B) followed by adjuvant intravesical treatment with cytostatic drugs or Bacillus Calmette–Guérin (BCG) as standard therapy of non-muscle-invasive bladder cancer (NMIBC) is associated with a high recurrence rate of about 60–70%, considerable side effects and requires close monitoring. Alternative treatment options are warranted. Two patients with epithelial cell adhesion molecule (EpCAM)-positive recurrent non-muscle invasive bladder cancer were treated the first time by an intravesical administration of the trifunctional bispecific EpCAM targeting antibody catumaxomab (total dosage of 470 and 1120 µg, respectively). The binding and killing activity of catumaxomab in urine milieu was evaluated in vitro. In contrast to its previous systemic application catumaxomab was well tolerated without any obvious signs of toxicity. Relevant cytokine plasma levels were not detected and no significant systemic drug release was observed. The induction of a human anti-mouse-antibody (HAMA) reaction was either absent or untypically weak contrary to the high immunogenicity of intraperitoneal applied catumaxomab. Tumor cells that were detectable in urine patient samples disappeared after catumaxomab therapy. Endoscopically confirmed recurrence-free intervals were 32 and 25 months. Our data suggest that intravesical administration of catumaxomab in NMIBC is feasible, safe and efficacious, thus arguing for further clinical development of catumaxomab in this indication.
A modified culture medium and hyphae isolation method can increase quality of the RNA extracted from mycelia of a dimorphic fungal species
Authors: Papp László Attila , Ács-Szabó Lajos , Póliska Szilárd , Miklós Ida
Published: April 2021

The capability of RNA isolation with good efficiency and high quality is essential for a downstream application such as RNA sequencing. It requires successful cell culturing and an effective RNA isolation method. Although effective methods are available, production of the homogenous mycelia and extraction of good-quality mycelial RNA from true invasive hyphae, which penetrated into the agar plates, are difficult. To overcome these problems, the aim of this study was to develop technical modifications which allow production of homogenous mycelial biomass without extra stimuli agents and improve quality of the RNA extracted from the fungal hyphae. Our alternative culture medium was suitable for production both yeast-phase cells and hyphae of the Schizosaccharomyces japonicus and other dimorphic species, such as the Candida albicans, Saccharomyces cerevisiae, and Jaminaea angkorensis. To improve quality of the mycelial RNA, we developed an isolation procedure of the hyphal tip, which eliminated the unnecessary vacuoles-containing parts of the hyphae. To increase RNA quantity, we used glass beads in the RNA extraction protocol to achieve stronger breaking of the mycelial walls. All these modifications can also be useful for researchers working with other dimorphic fungi and can contribute to the higher comparability of the transcriptional data coming from yeast-phase cells and hyphae or even from different species.
The course of subjective and objective chemosensory dysfunction in hospitalized patients with COVID-19: a 6-month follow-up
Authors: Bertlich Mattis , Stihl Clemens , Lüsebrink Enzo , Hellmuth Johannes C. , Scherer Clemens , Freytag Saskia , Spiegel Jennifer Lee , Stoycheva Ivelina , Canis Martin , Weiss Bernhard G. , Ihler Friedrich , Haubner Frank
Published: April 2021

Purpose

It has been established that the infection with SARS-CoV-2 may cause an impairment of chemosensory function. However, there is little data on the long-term effects of SARS-CoV-2 infection on chemosensory function.

Methods

Twenty three SARS-CoV-2-positive patients diagnosed in spring 2020 with subjective hyposmia (out of 57 positive patients, 40.3%) were compared to SARS-CoV-2-positive patients without hyposmia (n = 19) and SARS-CoV-2-negative patients (n = 14). Chemosensory function was assessed by the Brief Smell Identification Test (BSIT), Taste Strips (TS), Visual Analogue Scales (VAS), and the SNOT-22. The initial cohort with hyposmia were also examined at 8 weeks and 6 months after initial examination.

Results

There were no differences between the SARS-CoV-2-positive cohort without hyposmia and negative controls in terms of BSIT (8.5 ± 2.6 vs. 10.2 ± 1.8), TS (3.4 ± 0.6 vs. 3.9 ± 0.3) or VAS (2.1 ± 1.3 vs. 1.1 ± 0.5); yet the SNOT-22 was significantly elevated (27.7 ± 11.2 vs. 16.4 ± 10.8). The SARS-CoV-2-positive group with hyposmia performed significantly poorer in BSIT (4.0 ± 1.7 vs. 8.5 ± 2.6/10.2 ± 1.8), TS (2.6 ± 1.3 vs. 3.4 ± 0.6/3.9 ± 0.3), and VAS (7.9 ± 2.2 vs. 2.1 ± 1.3/1.1 ± 0.5) compared to both control groups. At week 8 and month 6 control, six and five patients, respectively, still suffered from subjectively and objectively impaired chemosensory function. The other patients had recovered in both respects.

Conclusion

SARS-CoV-2 patients with subjectively impaired chemosensory function regularly perform poorly in objective measurements. About 70% of patients suffering from olfactory dysfunction in SARS-CoV-2 quickly recover—the rest still suffers from considerable impairment 6 months after infection.