bluuebunny/crossref_metadata_2025 huggingface dataset:
A resource efficient scheme for backhaul‐constrained coordinated multipoint cellular networks
Authors: Gulia Sandeep , Ahmad Anwar , Singh Manish Kumar
Published: November 2021

The coordinated multipoint (CoMP) is a promising set of techniques that deals with inter‐cell interference differently than the conventional interference mitigation schemes. This unique approach can effectively mitigate or even exploit the interference, turning it into a useful signal. The CoMP was first introduced in Release‐11 by Third Generation Partnership Project (3GPP) for the fourth generation (4G) long term evolution‐advanced (LTE‐A) systems, enhanced in subsequent releases and recently incorporated as one of the fifth generation (5G) component technologies. In this article, we propose two techniques aiming to improve the performance of existing CoMP schemes. First, we examine the impact of constraint backhaul on the cell coordination and propose an optimal CoMP mechanism that adaptively switches between joint transmission (JT) and coordinated beamforming (CBF) CoMP schemes taking into consideration the average sum rate and the available backhaul capacity. Next, we present a backhaul overhead reduction scheme for CoMP enabled networks, which extends the performance gains of adaptive CoMP scheme. Simulation results suggest that proposed adaptive scheme outclasses conventional CoMP schemes and offers a spectrally efficient solution with increased average user throughput and sum rate.
Fatty Liver and the Coronavirus Disease 2019 Pandemic: Health Behaviors, Social Factors, and Telemedicine Satisfaction in Vulnerable Populations
Authors: Kim Rebecca G. , Medina Sheyla P. , Magee Catherine , Khalili Mandana
Published: November 2021

The coronavirus disease 2019 (COVID‐19) pandemic has impacted health‐related behaviors that influence fatty liver disease (FLD) management. We evaluated the impact of the pandemic on FLD management and satisfaction with care delivery in this population. In the San Francisco safety‐net hepatology clinics, we evaluated health‐related behaviors and factors associated with self‐reported weight gain during the COVID‐19 pandemic as well as satisfaction with telemedicine in adults with FLD by using multivariable modeling. From June 1, 2020, to May 5, 2021, 111 participants were enrolled. Median age was 52 years, 30% were men, 63% were Hispanic, 21% were Asian/Pacific Islander, and 9% were White. Eating habits were unchanged or healthier for 80%, physical activity decreased in 51%, 34% reported weight gain, and 5% reported increased alcohol intake. Forty‐five percent had severe depressive symptoms, 38% in those without diagnosed depression and 60% of individuals with heavy alcohol use. On multivariable analysis, decreased physical activity (odds ratio [OR], 4.8) and heavy alcohol use (OR, 3.4) were associated with weight gain (all P < 0.05). Among those with telemedicine visits (n = 66), 62% reported being very satisfied. Hispanic ethnicity was associated with a 0.8‐unit decrease in the telemedicine satisfaction score (P = 0.048) when adjusting for sex, age, and pandemic duration. Conclusion: During the pandemic, decreased physical activity and heavy alcohol use were most influential on self‐reported weight gain in FLD. Maintenance of healthy eating and increased physical activity, alcohol cessation counseling, and mental health services are critical in preventing poor FLD‐associated outcomes during the pandemic recovery. Dissatisfaction with telemedicine should be explored further to ensure equitable care, especially among the vulnerable Hispanic population.
Analysis of heat transfer through different profiled longitudinal porous fin by differential transformation method
Authors: Sowmya G. , Gireesha Bijjanal Jayanna
Published: November 2021

A porous fin of longitudinal geometry with different profiles like rectangular, triangular, and convex shapes is considered in the present investigation. The totally wet condition under the existence of natural convection and radiation has been examined. In addition, the generation of thermal‐dependent internal heat is studied. The analysis also concentrates on the material of the fin. Here, the fin made up of aluminum and copper metal is taken for scrutinization. The derived ordinary differential equation was solved by the differential transform method. The obtained consequences have been graphically interpreted. It is determined that the fin made up of aluminum material dissipates more heat than the copper material fin.
Thermal instability of a power‐law fluid‐saturated porous layer with an internal heat source and vertical throughflow
Authors: Reddy Gundlapally Shiva Kumar , Ragoju Ravi
Published: November 2021

The thermal instability of internally heated convection in a porous medium saturated by a power‐law (PL) fluid is studied. The governing dimensionless equations are solved using the normal mode approach, which leads to an eigenvalue problem for the linear stability theory. The neutral curves are obtained for different prescribed values of the other physical parameters. The effect of the PL index, internal heat source parameter, and Peclet number on the onset of instability was analyzed. Furthermore, an analytical solution is obtained for the regime of small wave numbers by using asymptotic analysis.
Turbidity‐discharge hysteresis in a meso‐scale catchment: The importance of intermediate scale events
Authors: Lannergård Emma E. , Fölster Jens , Futter Martyn N.
Published: November 2021

In‐situ sensors for riverine water quality monitoring are a powerful tool to describe temporal variations when efficient and informative analyses are applied to the large quantities of data collected. Concentration‐discharge hysteresis patterns observed during storm events give insights into headwater catchment processes. However, the applicability of this approach to larger catchments is less well known. Here, we evaluate the potential for high‐frequency turbidity‐discharge (Q) hysteresis patterns to give insights into processes operating in a meso‐scale (722 km2) northern mixed land use catchment. As existing event identification methods did not work, we developed a new, objective method based on hydrograph characteristics and identified 76 events for further analysis. Qualitative event analysis identified three recurring patterns. Events with low mean Q (≤ 2 m3/s) often showed short‐term, quasi‐periodic turbidity variation, to a large extent disconnected from Q variation. High max Q events (≥15 m3/s) were often associated with spring flood or snowmelt, and showed a disconnection between turbidity and Q. Intermediate Q events (mean Q: 2–11 m3/s) were the most informative when applying hysteresis indexes, since changes in turbidity and Q were actually connected. Hysteresis indexes could be calculated on a subset of 60 events, which showed heterogeneous responses: 38% had a clockwise response, 12% anticlockwise, 12% figure eight (clockwise–anticlockwise), 10% reverse figure eight (anticlockwise–clockwise) and 28% showed a complex response. Clockwise hysteresis responses were associated with the wetter winter and spring seasons. Generally, changes in Q and turbidity were small during anticlockwise hysteresis events. Precipitation often influenced figure‐eight patterns, while complex patterns often occurred during summer low flows. Analysis of intermediate Q events can improve process understanding of meso‐scale catchments and possibly aid in choosing appropriate management actions for targeting a specific observed pattern.
Inhibiting octahedral tilting for stable CsPbI2Br solar cells
Authors: Wang Aili , Wang Jianwei , Niu Xiaobin , Zuo Chuantian , Hao Feng , Ding Liming
Published: November 2021

The intrinsic phase instability of CsPbI2Br perovskite hinders its development and application in solar cells. Herein, we adopt 1‐butyl‐3‐methylimidazolium hexafluorophosphate (BMIMPF6), a hydrophobic ionic liquid (IL), to improve the phase stability of CsPbI2Br. Density functional theory calculation reveals that the formation energy of CsPbI2Br with BMIMPF6 is reduced, thereby restraining the [PbX6]4− octahedral tilting. The reduced structural distortion and relaxed lattice strain result in improved phase stability of CsPbI2Br. In addition, the interfacial dipole moment increases after introducing BMIMPF6, which facilitates the charge transfer. Consequently, the CsPbI2Br solar cells with BMIMPF6 deliver a power conversion efficiency (PCE) of 16.2% along with excellent stability. The unencapsulated devices with BMIMPF6 maintain 98.9%, 88.6%, and 99.5% of the initial PCEs after 1200 h storage in N2, 1000 h storage in air (30% relative humidity), and 200 thermal cycles (25–100°C), respectively.

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Multiscale photoacoustic imaging without motion using single‐pixel imaging
Authors: Song Xianlin , Yu Xiaohai , Wang Rui , Chen Ganyu , Zeng Jiahao
Published: November 2021

The conventional photoacoustic microscopy usually uses mechanical raster scanning to obtain three‐dimensional information, and the imaging speed is limited. Meanwhile, the conventional photoacoustic microscopy can only be performed at one single scale due to fixed resolution, it cannot make full use of multiscale information for integrated imaging. Here, we proposed a multiscale photoacoustic microscopy based on single‐pixel imaging. A sequence of sinusoidal fringes with varying spatial frequencies is used to obtain the Fourier coefficients in the case of a single ultrasonic transducer. By controlling the spatial frequency of fringe, the acquisition of Fourier coefficients can be controlled and multiscale imaging can be achieved. The feasibility of this method is verified by theory and simulation. The results show that the lateral resolution can be tuned from several microns to tens of microns without mechanical scanning. This method will expand the application of photoacoustic imaging in biomedical research.
3D‐QSAR, molecular docking, molecular dynamics, and ADME/T analysis of marketed and newly designed flavonoids as inhibitors of Bcl‐2 family proteins for targeting U‐87 glioblastoma
Authors: Poustforoosh Alireza , Faramarz Sanaz , Nematollahi Mohammad Hadi , Hashemipour Hassan , Tüzün Burak , Pardakhty Abbas , Mehrabani Mehrnaz
Published: November 2021

Glioblastoma is the most common and destructive brain tumor with increasing complexity. Flavonoids are versatile natural compounds with the approved anticancer activity, which could be considered as a potential treatment for glioblastoma. A quantitative structure‐activity relationship (QSAR) can provide adequate data for understanding the role of flavonoids structure against glioblastoma. The IC50 of various flavonoids for the U‐87 cell line was used to prepare an adequate three‐dimensional QSAR (3D‐QSAR) model. The validation of the model was carried out using some statistical parameters such as R2 and Q2. Based on the QSAR model, the activities of other marketed and newly designed flavonoids were predicted. Molecular docking study and molecular dynamics (MD) simulation were conducted for better recognition of the interactions between the most active compounds and Bcl‐2 family proteins. Moreover, an AMDE/T analysis was performed for the most active flavonoids. A reliable 3D‐QSAR was performed with R2 and Q2 of 0.91 and 0.82. The molecular docking study revealed that BCL‐XL has a higher binding affinity with the most active compounds, and the MD simulation showed that some residues of the BH3 domain, such as Phe97, Tyr101, Arg102, and Phe105 create remarkable hydrophobic interactions with the ligands. ADME/T analysis also showed the potential of the active compounds for further investigation. 3D‐QSAR study is a beneficial method to evaluate and design anticancer compounds. Considering the results of the molecular docking study, MD simulation, and ADME/T analysis, the designed compound 54 could be considered as a potential treatment for glioblastoma.
Age‐related changes in the energy of human mesenchymal stem cells
Authors: Barilani Mario , Lovejoy Christopher , Piras Roberta , Abramov Andrey Y. , Lazzari Lorenza , Angelova Plamena R.
Published: November 2021

Aging is a physiological process that leads to a higher risk for the most devastating diseases. There are a number of theories of human aging proposed, and many of them are directly or indirectly linked to mitochondria. Here, we used mesenchymal stem cells (MSCs) from young and older donors to study age‐related changes in mitochondrial metabolism. We have found that aging in MSCs is associated with a decrease in mitochondrial membrane potential and lower NADH levels in mitochondria. Mitochondrial DNA content is higher in aged MSCs, but the overall mitochondrial mass is decreased due to increased rates of mitophagy. Despite the higher level of ATP in aged cells, a higher rate of ATP consumption renders them more vulnerable to energy deprivation compared to younger cells. Changes in mitochondrial metabolism in aged MSCs activate the overproduction of reactive oxygen species in mitochondria which is compensated by a higher level of the endogenous antioxidant glutathione. Thus, energy metabolism and redox state are the drivers for the aging of MSCs/mesenchymal stromal cells.
Pharmacokinetics and Concentration‐Response of Dupilumab in Patients With Seasonal Allergic Rhinitis
Authors: Kamal Mohamed A. , Franchetti Yoko , Lai Ching‐Ha , Xu Christine , Wang Claire Q. , Radin Allen R. , O'Brien Meagan P. , Ruddy Marcella , Davis John D.
Published: November 2021

Patients with moderate to severe allergic rhinitis may benefit from subcutaneous immunotherapy (SCIT), despite the risk of systemic allergic reaction. Dupilumab is a fully human monoclonal antibody that blocks the shared receptor component for interleukin‐4 and interleukin‐13, key drivers of the type 2 inflammation seen in allergic rhinitis, thereby inhibiting their signaling. In the LIBERTY Grass AID trial (NCT03558997), 16 weeks of treatment with 300 mg of dupilumab every 2 weeks plus timothy grass (TG) SCIT did not reduce TG allergen challenge nasal symptom scores compared with SCIT only but did improve tolerability of SCIT up‐titration in patients with a history of grass pollen–induced seasonal allergic rhinitis. Here, we present the pharmacokinetics of functional serum dupilumab and concentration‐response relationships in 52 patients enrolled in this trial. Functional dupilumab concentrations and concentrations of TG‐specific IgE and IgG4 were assessed in blood samples collected from dupilumab‐only and SCIT + dupilumab–treated groups. Mean functional dupilumab concentrations were similar in both groups and reached a steady state of ≈70–80 mg/L at week 5. One week after the end of treatment, TG‐specific IgG4 concentrations were increased in the SCIT + dupilumab group, but not in the dupilumab‐only group, over the range of dupilumab concentrations evaluated, whereas no changes were seen for TG‐specific IgE concentrations. This study demonstrates that SCIT does not alter functional concentrations of serum dupilumab, and the impact of SCIT on TG‐specific immunoglobulins is not affected by functional dupilumab concentrations over the range studied, indicating that maximum response was achieved in all patients.
Segment number threshold determines juvenile onset of germline cluster expansion in Platynereis dumerilii
Authors: Kuehn Emily , Clausen David S. , Null Ryan W. , Metzger Bria M. , Willis Amy D. , Özpolat B. Duygu
Published: November 2021

Development of sexual characters and generation of gametes are tightly coupled with growth. Platynereis dumerilii is a marine annelid that has been used to study germline development and gametogenesis. P. dumerilii has germ cell clusters found across the body in the juvenile worms, and the clusters eventually form the gametes. Like other segmented worms, P. dumerilii grows by adding new segments at its posterior end. The number of segments reflect the growth state of the worms and therefore is a useful and measurable growth state metric to study the growth‐reproduction crosstalk. To understand how growth correlates with progression of gametogenesis, we investigated germline development across several developmental stages. We discovered a distinct transition period when worms increase the number of germline clusters at a particular segment number threshold. Additionally, we found that keeping worms short in segment number, by manipulating environmental conditions or via amputations, supported a segment number threshold requirement for germline development. Finally, we asked if these clusters in P. dumerilii play a role in regeneration (as similar free‐roaming cells are observed in Hydra and planarian regeneration) and found that the clusters were not required for regeneration in P. dumerilii, suggesting a strictly germline nature. Overall, these molecular analyses suggest a previously unidentified developmental transition dependent on the growth state of juvenile P. dumerilii leading to substantially increased germline expansion.
Diffusion Kurtosis MR Imaging of Invasive Breast Cancer: Correlations With Prognostic Factors and Molecular Subtypes
Authors: Kang Han Sol , Kim Jin You , Kim Jin Joo , Kim Suk , Lee Nam Kyung , Lee Ji Won , Suh Hie Bum , Hwangbo Lee , Son Yohan , Grimm Robert
Published: November 2021

Background

The associations between diffusion kurtosis imaging (DKI)‐derived parameters and clinical prognostic factors of breast cancer have not been fully evaluated; this knowledge may have implications for outcome prediction and treatment strategies.

Purpose

To determine associations between quantitative diffusion parameters derived from DKI and diffusion‐weighted imaging (DWI) and the prognostic factors and molecular subtypes of breast cancer.

Study Type

Retrospective.

Population

A total of 383 women (mean age, 53.8 years; range, 31–82 years) with breast cancer who underwent preoperative breast MRI including DKI and DWI.

Field Strength/Sequence

A 3.0 T; DKI using a spin‐echo echo‐planar imaging (EPI) sequence (b values: 200, 500, 1000, 1500, and 2000 sec/mm2), DWI using a readout‐segmented EPI sequence (b values: 0 and 1000 sec/mm2) and dynamic contrast‐enhanced breast MRI.

Assessment

Two radiologists (J.Y.K. and H.S.K. with 9 years and 1 year of experience in MRI, respectively) independently measured kurtosis, diffusivity, and apparent diffusion coefficient (ADC) values of breast cancer by manually placing a regions of interest within the lesion. Diffusion measures were compared according to nodal status, grade, and molecular subtypes.

Statistical Tests

Kruskal–Wallis test, Mann–Whitney U test with Bonferroni correction, receiver operating characteristic (ROC) analysis, and multivariate logistic regression analysis. (Statistical significance level of P < 0.05).

Results

All diffusion measures showed significant differences according to axillary nodal status and histological grade. Kurtosis showed significant differences among molecular subtypes. The luminal subtype (median 1.163) showed a higher kurtosis value compared to the HER2‐positive (median 0.962) or triple‐negative subtypes (median 1.072). ROC analysis for differentiating HER2‐positive from luminal subtypes revealed that kurtosis yielded the highest area under the curve of 0.781. In multivariate analyses, kurtosis remained a significant factor associated with differentiation between HER2‐positive and luminal (odds ratio [OR] = 0.993), triple‐negative and luminal (OR = 0.995), and HER2‐positive and triple‐negative subtypes (OR = 0.994).

Data conclusion

Quantitative diffusion parameters derived from DKI and DWI are associated with prognostic factors for breast cancer. Moreover, DKI‐derived kurtosis can help distinguish between the molecular subtypes of breast cancer.

Evidence Level

4

Technical Efficacy

3
Getting ahead or getting along? How motivational orientations forge newcomers' cohort network structures, task assistance, and turnover
Authors: Zhou Jinyi , Li Ning , Chi Wei
Published: November 2021

Social connections play a vital role in helping newcomers fit into a new work environment. In addition to seeking valuable support from organizational “insiders” such as coworkers and leaders, newcomers also need support from other newcomers with similar experience during the onboarding process. Drawing upon socioanalytic theory, we propose that newcomers with a competitive or cooperative orientation will follow different networking patterns within their friendship cohort network. Specifically, newcomers with a highly competitive orientation will experience a high increase in coreness centrality in the friendship cohort network, which captures employees' relative position (i.e., core or periphery) in the entire cohort, while those with a highly cooperative orientation will have a high increase in in‐degree centrality, which reflects the number of personal friendship ties. To test our hypotheses, a cohort of 607 newcomers in a manufacturing company was tracked for 18 months (in seven waves) and the results show that competitive orientation is positively related to newcomers' increase in coreness centrality and that a cooperative orientation is positively related to an increase in in‐degree centrality. Furthermore, the increase in coreness centrality is positively related to newcomers' task assistance from other newcomers, which in turn reduces their likelihood of leaving the organization.
Broad‐spectrum antimicrobial activity of cinnamoyl esterase‐producing Lactobacilli and their application in fermented rice bran
Authors: Kim Jong‐Hui , Lee Eun‐Seon , Kim Bu‐Min , Ham Jun‐Sang , Oh Mi‐Hwa
Published: November 2021

BACKGROUND

Cinnamoyl esterase (CE) can release antioxidant phenolic acids from its non‐digestible ester‐linked form. Fermentation using CE‐producing lactic acid bacteria (LAB) can be useful in the food industry because of its ability to produce bioactive compounds and antibacterial metabolites. The purpose of this study was to confirm the food applicability of LAB with CE‐producing ability and broad‐spectrum antibacterial activity.

RESULTS

Among the 219 bacterial strains identified in infant feces, five Lactobacillus gasseri and six Limosilactobacillus fermentum with a high CE activity were isolated. The survival rate of all selected LABs was > 95% at pH 2.5 for 3 h and > 70% when treated with 0.3% bile salt for 4 h. Moreover, cell‐free supernatants of all strains strongly inhibited five food‐borne bacterial pathogens (Listeria monocytogenes, Salmonella enterica, Escherichia coli O157:H7, Bacillus cereus, and Staphylococcus aureus) and three toxin‐producing fungal pathogens (Aspergillus niger, Penicillium sp., and Fusarium oxysporum). To improve phenolic acid content and rice bran preservation, Limosilactobacillus fermentum J2 with the strongest CE activity and Lactobacillus gasseri N2 with the strongest antibacterial activity were used in rice bran fermentation, respectively. FRB‐J2 (fermented rice bran with Limosilactobacillus fermentum J2) and FRB‐N2 (fermented rice bran with Lactobacillus gasseri N2) significantly increased caffeic acid and ferulic acid (P < 0.01). FRB‐J2 and FRB‐N2 artificially inoculated with F. oxysporum showed no visible fungal growth during the test period (21 days).

CONCLUSION

Fermentation by Limosilactobacillus fermentum J2 and Lactobacillus gasseri N2 can help extend the shelf life of rice bran‐based products and produce bioactive compounds. © 2021 Society of Chemical Industry.
Sensitivity and specificity of the Posttraumatic Stress Disorder Checklist for DSM‐5 in a Canadian psychiatric outpatient sample
Authors: Boyd Jenna E. , Cameron Duncan H. , Shnaider Philippe , McCabe Randi E. , Rowa Karen
Published: November 2021

The Posttraumatic Stress Disorder (PTSD) Checklist for DSM‐5 (PCL‐5) is a widely used, self‐report measure that is employed to assess PTSD symptom severity and determine the presence of probable PTSD in various trauma‐exposed populations. The PCL‐5 is often administered in clinical settings as a screening tool for PTSD, with a suggested cutoff score of 33 indicating a probable PTSD diagnosis. Recent research indicates that a higher cutoff may be required in psychiatric samples. In the present study, we aimed to determine the sensitivity and specificity of the PCL‐5 in a Canadian outpatient psychiatric sample and establish an optimal cutoff score for detecting probable PTSD in this sample. Participants were 673 individuals who reported a history of trauma exposure and were assessed using a semistructured interview and self‐report measures. Individuals diagnosed with PTSD (N = 193) reported a mean PCL‐5 score of 56.57, whereas individuals without PTSD (N = 480) reported a mean score of 33.56. A score of 45 was determined to be the optimal cutoff score in this sample, balancing sensitivity and specificity while detecting a probable diagnosis of PTSD. Consistent with findings in other psychiatric samples, these findings indicate that in an outpatient psychiatric sample with a history of exposure to a variety of trauma types, a higher cutoff score is required to determine probable PTSD. In addition, given the estimated rate of false positives even with a higher cutoff, follow‐up diagnostic assessments are recommended.
Fetal Sacral Ratio
Authors: Perlman Sharon , Shwartz Itai , Hazan Yenon , Weissbach Avichai , Gilboa Yinon , Kravarusic Dragan , Samuk Inbal
Published: November 2021

Objectives

The sacral ratio (SR) was described as a postnatal X‐ray‐based method to detect sacral abnormalities and predict functional prognosis for fecal continence in children with anorectal malformations (ARMs). The present study aimed to describe a novel method of assessing sonographic fetal sacral ratio (f‐SR) in a normal population of fetuses.

Methods

Sixty three‐dimensional (3D) ultrasound reconstruction images of the sacrum obtained from routine low‐risk scans performed between 21 and 26 weeks of gestation served for measurement. The f‐SR was calculated in a coronal view as the ratio between lines drawn at the upper and lower levels of the iliac bone and the 5th sacral vertebra. Bland–Altman plots assessed the inter‐ and intrareader variabilities of measurements.

Results

The f‐SR in the normal population of fetuses was 0.913 (±0.094). During the study period, three cases with ARM were examined and had a mean f‐SR of 0.55. There was good repeatability of measurements and between readers' agreement.

Conclusions

The present study introduces a novel prenatal sonographic f‐SR that can be reliably calculated on prenatal 3D ultrasound with good reliability and reproducibility. Future research will identify the clinical significance of f‐SR abnormalities in ARM and their long‐term impact on continence.
Highest primary production achieved at high nitrogen levels despite strong stoichiometric imbalances with phosphorus in hypereutrophic experimental systems
Authors: Kelly Patrick T. , Taylor Jason M. , Andersen Isabelle M. , Stovall Jasmine , Scott J. Thad
Published: November 2021

Lakes in human‐dominated landscapes often face high loads of nutrients that may alter ecosystem function. High N loads relative to P are especially common in agricultural watersheds, where nitrate (NO3) in particular is elevated due to fertilizer application and runoff. While past research has focused extensively on the impact of nutrient loads on reductions in water quality, we still lack assessment of the impact of high N loading and extreme stoichiometric imbalance on ecosystem process rates, specifically measurements of gross primary production (GPP), ecosystem respiration (ER), and net ecosystem productivity (NEP). We used open‐bottomed experimental mesocosms (limnocorrals) to establish four treatments of increasing N : P by increasing N loads while leaving P loads consistent, and measured chlorophyll concentration and metabolic rates. We observed significant differences in productivity among treatments, with higher biomass and GPP in the highest two N : P treatments and a unimodal pattern between GPP and N concentrations. Declines in GPP at high N may have been due to limitation by P or light. In contrast to other studies, we did not observe any significant differences in ER with fertilization, potentially from a lack of dissolved organic carbon loading often associated with higher nutrient concentrations in those lakes. Maximum GPP and NEP observed here was far above commonly cited thresholds for likely P limitation at a molar N : P of approximately 330. Our results highlight the potential for high productivity despite stoichiometric imbalance that is common in agricultural systems, suggesting N management may be important in reducing primary production in hypereutrophic lakes.
Effect of increased CO2 on iron‐light‐CO2 co‐limitation of growth in a marine diatom
Authors: Ye Youting , Sunda William G. , Hong Haizheng , Shi Dalin
Published: November 2021

Light affects iron (Fe) growth requirements in marine phytoplankton while CO2 can influence energy allocation and light sensitivity. Therefore, ongoing increases in seawater CO2 concentrations could impact the growth of Fe‐ and light‐limited phytoplankton. In this study, Phaeodactylum tricornutum was used as a model diatom to examine the interactive effects of Fe, light, and CO2 on photosynthesis, growth, and protein expression in marine phytoplankton. Low concentration of biologically available inorganic iron (Fe′) and low‐light intensity decreased specific rates of carbon (C)‐fixation and growth, and the two together had an even greater effect, indicating a co‐limitation. Increased partial pressure of CO2 from its current value (400 μatm) to 750 μatm had no effect at growth sufficient levels of Fe and light, but increased C‐fixation and growth rate under Fe or light limitation, and had an even greater effect in Fe and light co‐limited cells. The results suggest that ongoing increases in CO2 may increase C‐fixation rates in Fe‐ and light‐limited and co‐limited regions, which cover at least 30% of the ocean. Measurements of photosynthetic proteins in photosystems II and I, and transcripts of proteins involved in CO2 concentrating mechanisms (CCMs), photorespiration, and antioxidant protection, suggest that the benefit of increased CO2 in the Fe‐ and light‐limited cells was from a downregulation of CCMs and resultant decreased demands for energy supplied from photosynthesis, and from decreased rates of photorespiration, which consumes photosynthetically produced ATP and NADPH. A decrease in oxidative stress with increased CO2 also contributed.
Recent advances in the development of allosteric protein tyrosine phosphatase inhibitors for drug discovery
Authors: Elhassan Reham M. , Hou Xuben , Fang Hao
Published: November 2021

Protein tyrosine phosphatases (PTPs) superfamily catalyzes tyrosine de‐phosphorylation which affects a myriad of cellular processes. Imbalance in signal pathways mediated by PTPs has been associated with development of many human diseases including cancer, metabolic, and immunological diseases. Several compelling evidence suggest that many members of PTP family are novel therapeutic targets. However, the clinical development of conventional PTP‐based active‐site inhibitors originally was hampered by the poor selectivity and pharmacokinetic properties. In this regard, PTPs has been widely dismissed as “undruggable.” Nonetheless, allosteric modulation has become increasingly an influential and alternative approach that can be exploited for drug development against PTPs. Unlike active‐site inhibitors, allosteric inhibitors exhibit a remarkable target‐selectivity, drug‐likeness, potency, and in vivo activity. Intriguingly, there has been a high interest in novel allosteric PTPs inhibitors within the last years. In this review, we focus on the recent advances of allosteric inhibitors that have been explored in drug discovery and have shown an excellent result in the development of PTPs‐based therapeutics. A special emphasis is placed on the structure–activity relationship and molecular mechanistic studies illustrating applications in chemical biology and medicinal chemistry.
Investigation of Electrical Parameters of CdTe Photovoltaic Devices by Computational Analysis
Authors: Singh Nitesh Kumar , Agarwal Anshul , Kanumuri Tirupathiraju
Published: November 2021

This article discusses the numerical analysis of heterojunction photovoltaic cells based on cadmium telluride (CdTe) using the SCAPS‐1D software. A novel glass/FTO/SnO2/CdS/interdiffusion/CdTe/SnS2/Se photovoltaic cell design is proposed for investigation. Additionally, the effect of thickness variation in the p‐type CdTe film, thickness variation in the interdiffusion layer, defect density in the CdTe film, defect density in the interdiffusion layer, and acceptor concentration in the CdTe layer is studied in order to improve the photovoltaic cell's efficiency. The study determines an optimal thickness of 1 and 0.6 μm for the CdTe and interdiffusion layers, respectively, a defect density of 1 × 1014 cm−3 for the CdTe film and interdiffusion region, an interface defect density of 1 × 1010 cm−3 between CdTe/interdiffusion, SnS2/CdTe, and CdS/interdiffusion, and an acceptor concentration value of 8.5 × 1015 cm−3. The optimized CdTe photovoltaic cell structure with current density (Jsc) = 30.003 mA cm−2, open‐circuit voltage (Voc) = 1.061 V, and fill factor (FF) = 88.10% achieves a 28.07% efficiency, compared to the baseline CdTe photovoltaic cell structure with a 23.01% efficiency.
Thermal decomposition and fire‐extinguishing mechanism of CF3I: A combined theoretical and experimental study
Authors: Yu Rourou , Hu Wenhao , Zhang Xiao , Wang Xingyu , Tan Zhaoyang
Published: November 2021

As Halon extinguishers impose severe damage to the stratospheric ozone layer, Halon substitutions are urgently desired and explored. In this paper, the thermal decomposition mechanism, the fire‐extinguishing performance and mechanism were experimentally and theoretically investigated for Trifluoroiodomethane (CF3I). The theoretical results direct that CF3I and its main decomposition products (CF3· and I·) can react with OH· and H· to block the combustion chain reactions. Besides, reaction kinetics analysis also direct that CF3· and I· are more easily generated during the interaction between CF3I and the flame. And the minimum fire‐extinguishing concentration (MEC) of CF3I in extinguishing methane‐air flames is 3.42 vol%, which is lower than those of representative HFCs and HFO‐1336mzz(E) and even comparable to that of Halon 1301. Both the experimental and theoretical results suggest the promising applicability of CF3I in practical Halon replacement and the necessity of its further evaluation.
An Insight into Synthetic Strategies and Recent Developments of Dihydrofolate Reductase Inhibitors
Authors: Chawla Pooja , Teli Ghanshyam , Gill Rupinder Kaur , Narang Raj Kumar
Published: November 2021

The dihydrofolate reductase (DHFR) is a significant target in cancer, microbial infection, fungal infection, malaria, leishmaniasis, and tuberculosis, among other diseases. The DHFR gene was discovered in prokaryotes and eukaryotes in the late 1950s and is found in all dividing cells. DHFR inhibitors are used for a variety of medicinal purposes. Increased resistance to therapeutic agents such as anticancer, antibiotic, anti‐tuberculosis, and antifungal sparked interest in the development of potent, broad‐spectrum medicines to address the issues. DHFR is a critical target in the development of innovative solutions to address the issues. Methotrexate, trimethoprim, sulfonamides, pyrimethamine, aminopterin, methotrexate, edatrexate, and pralatrexate are only a few of the medications that target DHFR. These medications are known as DHFR inhibitors. These inhibitors block the enzyme dihydrofolate reductase, resulting in a folic acid synthesis pathway that is compromised. The DHFR is involved in the conversion of dihydrofolate to tetrahydrofolate. Purine, pyrazole, pyrimidine, triazole, oxadiazole, and other heterocyclic motifs have shown to have a potential effect on the DHFR. In the medicinal chemistry community, a better understanding of the so‐called enzyme and biochemical underpinnings responsible for enzyme selectivity has led to the development of improved, unique, and new treatments. Several researchers are working on DHFR inhibitors intensely, using a variety of synthetic techniques, molecular modelling, mechanistic studies, in‐vitro and in‐vivo biological evaluations, and structure‐activity relationships (SAR). This review, compiles the findings of several research groups during the last five years. The molecular biology of DHFR, its biosynthetic pathway, and the powerful structure of DFHR inhibitors discovered during the search are all included in this review. The study also includes the latest developments in synthetic methods, molecular docking, and structure‐activity relationships.
Conversion of Furfural into Aromatic Hydrocarbons Using Catalyst HZSM‐5 Treated with HCl Solution
Authors: Zhao Yan , Li Zongru , Shi Qiong , Wen Minyue , Song Linlin , Wang Rourou , Liu Yin , Zhu Jinbo
Published: November 2021

This paper presents a new preparation method for aromatics through the catalytic pyrolysis of furfural from biomass. The use of HZSM‐5 zeolite as a catalyst with different pore sizes, pore geometries, and acidity levels was investigated for the conversion of furfural into aromatics. Results showed that product selectivity was dependent on the pore size and radius of the zeolites. Catalyst and reaction conditions were critical in maximizing the selectivity of aromatic hydrocarbons. The highest yield of 58.49 wt% was achieved at 10 ml min−1 N2 purge rate, 0.5 ml h−1 feeding rate, 500 °C pyrolysis temperature, and 23 catalyst Si/Al ratio. The highest carbon yield of benzene (12.74 %), toluene (11.13 %), xylene (8.54 %), and total (30.85 %) was obtained when the HZSM‐5 zeolite was treated with HCl (0.9 mol/L) solution. On the basis of current experimental results and previous reports, the mechanism of Lewis and Bronsted acid sites was inferred.
Direct Cobalt‐Catalyzed Phosphorylation of Porphyrins
Authors: Kiselev Alexey N. , Zaitseva Svetlana V. , Zdanovich Sergei A. , Shagalov Evgeny V. , Aleksandriysky Viktor V. , Syrbu Sergei A. , Koifman Oscar I.
Published: November 2021

A new approach has been proposed for synthesizing porphyrins with phosphoryl substituents by Co‐and Mn‐catalyzed C−H‐functionalization. The paper shows the effect of the solvent, oxidizer, and catalyst, porphyrin, and phosphite nature on the yield and composition of reaction products. It is shown that cobalt porphyrins can interact with phosphites in the absence of a catalyst, forming the products of axial binding to the metal cation. The reaction mechanism has been proposed.
Cholesterol‐Based Conjugates: Synthesis, Characterization and In Vitro Biological Studies
Authors: Ruwizhi Ngoni , Adeyemi Samson A. , Ubanako Philemon , Morifi Eric , Fonkui Youmbi T. , Ndinteh Derek T. , Choonara Yahya E. , Aderibigbe Blessing A.
Published: November 2021

Bacterial infections, malaria and cancer are causes of high death rates. Most of the drugs used to combat these diseases suffer from drug resistance, poor absorption and bioavailability and toxic side effects. Cholesterol is a sterol abundantly found in the human body and forms part of the structure and organisation of cell membranes. It is readily available, has functional groups that can be easily modified, and is affordable. In this research, different known therapeutic agents (anticancer, antimalarial and antibacterial) were conjugated to cholesterol and the synthesized compounds were characterized using FTIR, 1H and 13C NMR, and Mass Spectroscopy, followed by in vitro antiplasmodial, antibacterial and anticancer studies. Thirteen compounds were successfully synthesized. Compound 10, containing curcumin and cholesterol was the most effective against all the Gram‐positive strains of bacteria while compounds 9–11, containing either curcumin or zidovudine scaffold were effective against all the strains of bacteria. Compound 13, containing pyrimethamine and cholesterol showed good antiplasmodial activity with 97.75 and 97.83 % inhibition of asexual parasite proliferation at 20 and 10 μg/mL concentrations, respectively. In vitro cytotoxicity of the synthesized compounds on HeLa (cervical cancer) cells revealed IC50 values for compounds 2 (7.559 μg/mL), 3 (5.840 μg/mL), 5 (1.44 mg/mL), 7 (4.308 μg/mL) and 11 (3.295 μg/mL) confirming promising anticancer activity.
A Site‐Selective C−N Bond Formation of 2,4‐Dichloro‐5H‐pyrano[2,3‐d]pyrimidines and Amide
Authors: Qin Jinjing , Li Zhenhua , Cao Yingyan , Xie Yuanyuan , Su Weike
Published: November 2021

A serious of C4‐position aniline functionalized 5H‐pyrano[2,3‐d]pyrimidine derivatives were synthesized from the corresponding chlorinated pyrimidines and acetanilides. This process was approached by treating the acetanilide with NaH instead of aniline, where a dissociation of the acyl group in situ happened during the reaction. The strategy worked out the non‐reactive route resulted from the low reactivity of aniline. This C−N bond formation features mild reaction conditions, simple execution, and broad substrate scope.
Development of a Flexible Tripodal Hydroxypyridinone Ligand with Cyclohexane Framework: Complexation, Solution Thermodynamics, Spectroscopic and DFT Studies
Authors: Dash Dibyajit , Baral Minati , Kanungo Bikram K
Published: November 2021

Conformationally flexible ligands of appropriate size and denticity can wrap to a metal ion with high stability. In this perspective, a new tripodal siderophore‐mimic hexadentate chelator, N‐[3,5‐bis[(1‐hydroxy‐6‐oxo‐pyridine‐2‐carbonyl)amino]cyclohexyl]‐1‐hydroxy‐6‐oxo‐pyridine‐2‐carboxamide, (TACH‐1,2‐HOPO), which contains three 1,2‐hydroxypyridinone units attached to a cyclohexane ring through amide linkage at 1,3 and 5 positions, has been designed and synthesized. The characterization of the ligand was carried out through various techniques like FT‐IR, 1H NMR, 13C NMR, ESI‐MS, and electronic spectroscopy. In an aqueous medium, the solution thermodynamics and photophysical properties of the chelator and its La3+, Gd3+, and Lu3+ complexes were determined experimentally as well as theoretically. The pKa values for the ligand were found to be 8.40, 5.74, and 5.39. Formation of lanthanide complexes of type MLH3, MLH2, MLH, ML, and ML.(H2O)x (x=1,2 and 3) was perceived, and the log βmlh for various partially and fully protonated and hydrated lanthanide complexes are reported. Theoretical calculations by DFT supported the experimental results. The experimentally determined protonation constants gave the same trend of ΔG0 values obtained by DFT; also, the theoretically calculated FT‐IR, 1H, 13C NMR, electronic, and excitation spectral data are in covenant with experimental findings. The bonding behavior between the lanthanide ions and the TACH‐1,2‐HOPO explicated by implication of NBO, Morokuma Ziegler energy decomposition analysis (ETS‐NOCV), propose the Ln−L bonds are less covalent with the trend Lu>Gd>La.
Photothermal‐Activatable Liposome Carrying Tissue Plasminogen Activator for Photoacoustic Image‐Guided Ischemic Stroke Treatment
Authors: Cai Xiaolei , Bandla Aishwarya , Wang Can , Liu Yu-Hang , Chuan Chan Kim , Xu Yu , Liu Xingang , Xu Shidang , Wu Wenbo , Thakor Nitish V. , Liu Bin
Published: November 2021

Ischemic stroke is a highly prevalent cause of mortality and morbidity. The only FDA‐approved treatment is thrombolysis using tissue plasminogen activator (tPA), which possesses a short effective time window. Real‐time recanalization monitoring is crucial to establish successful reperfusion and serves as a strong predictor of clinical outcomes. First‐line clinical imaging techniques, such as computed tomography and magnetic resonance imaging, are limited in their soft‐tissue resolution, scanning speed, and accessibility. Transcranial doppler ultrasound, the current gold standard for recanalization monitoring, is a blind technique and highly operator dependent. Herein, a photothermal‐activatable liposome carrying tPA for photoacoustic (PA) image‐guided therapy for real‐time and precise recanalization monitoring of ischemic stroke is designed. The liposome containing an organic molecule with propeller structures exhibits excellent photothermal properties and significantly amplified PA signals as compared with the widely used polymer nanoparticles. Near‐infrared (NIR) laser triggers rapid release of tPA for quick blood clot lysis in vitro. Administration of the liposome in a rat photothrombotic ischemia model facilitates high‐resolution PA imaging for precise real‐time recanalization assessment. Precisely controlled tPA release at the ischemic region is achieved by PA image‐guided NIR laser irradiation, which successfully dissolves the blood clot and restores perfusion, making this design promising for translational applications.
Cryptographic Protocol Analysis and Compilation Using CPSA and Roletran
Authors: Ramsdell John D.
Published: November 2021

The Cryptographic Protocol Shapes Analyzer cpsa determines if a cryptographic protocol achieves authentication and secrecy goals. It can be difficult to ensure that an implementation of a protocol matches up with what cpsa analyzed, and therefore be sure the implementation achieves the security goals determined by cpsa.

Roletran is a program distributed with cpsa that translates a role in a protocol into a language independent description of a procedure that is easily translated into an existing computer language. This paper shows how we ensure the procedure produced by Roletran is faithful to strand space semantics and therefore achieves the security goals determined by cpsa.

Real implementations of cryptographic functions make use of probabilistic encryption, but cpsa will conclude that two encryptions are the same if they are constructed with the same plaintext and key. The paper concludes by showing how we ensure that executions of generated code that make use of probabilistic encryption achieve the goals determined by cpsa.
Surface defect, anomalies and b-extremization
Authors: Wang Yifan
Published: November 2021

Abstract

Quantum field theories (QFT) in the presence of defects exhibit new types of anomalies which play an important role in constraining the defect dynamics and defect renormalization group (RG) flows. Here we study surface defects and their anomalies in conformal field theories (CFT) of general spacetime dimensions. When the defect is conformal, it is characterized by a conformal b-anomaly analogous to the c-anomaly of 2d CFTs. The b-theorem states that b must monotonically decrease under defect RG flows and was proven by coupling to a spurious defect dilaton. We revisit the proof by deriving explicitly the dilaton effective action for defect RG flow in the free scalar theory. For conformal surface defects preserving $$ \mathcal{N} $$
N
= (0, 2) supersymmetry, we prove a universal relation between the b-anomaly and the ’t Hooft anomaly for the U(1)r symmetry. We also establish the b-extremization principle that identifies the superconformal U(1)r symmetry from $$ \mathcal{N} $$
N
= (0, 2) preserving RG flows. Together they provide a powerful tool to extract the b-anomaly of strongly coupled surface defects. To illustrate our method, we determine the b-anomalies for a number of surface defects in 3d, 4d and 6d SCFTs. We also comment on manifestations of these defect conformal and ’t Hooft anomalies in defect correlation functions.
Applying the rescaling bootstrap under imputation for a multistage sampling design
Authors: Bruch Christian
Published: November 2021

In this paper, we propose a method that estimates the variance of an imputed estimator in a multistage sampling design. The method is based on the rescaling bootstrap for multistage sampling introduced by Preston (Surv Methodol 35(2):227–234, 2009). In his original version, this resampling method requires that the dataset includes only complete cases and no missing values. Thus, we propose two modifications for applying this method to nonresponse and imputation. These modifications are compared to other modifications in a Monte Carlo simulation study. The results of our simulation study show that our two proposed approaches are superior to the other modifications of the rescaling bootstrap and, in many situations, produce valid estimators for the variance of the imputed estimator in multistage sampling designs.