bluuebunny/crossref_metadata_2025 huggingface dataset:
Metal‐Free Photoinduced Atom Transfer Radical Polymerization for Highly Sensitive Detection of Lung Cancer DNA
Authors: Liu Qianrui , Jian Lihe , Liu Ruiqian , Yang Huaixia , Kong Jinming , Zhang Xueji
Published: November 2019

Convenient and sensitive detection of biomolecules is of great significance to disease diagnosis. In this work, a metal‐free photoinduced atom transfer radical polymerization (photoATRP) by a reductive quenching pathway as a novel strategy is applied to achieve lung cancer DNA detection. Thiolated PNA is exploited to specifically recognize target DNA, and the initiator of photoATRP is linked to the electrode surface via phosphate‐Zr4+‐carboxylate. Under the excitation of blue light, the reductive quenching pathway is activated with eosin Y (EY) as photoredox catalyst and N,N,N′,N′′,N′‐pentamethyldiethylenetriamine (PMDETA) as electron donor, and numerous polymeric chains are formed. Under optimal conditions, the linear range of this strategy is from 0.1 pm to 10 nm (R2=0.989) with a limit of detection (LOD) of 1.4 fm (14 zmol in 10 μL). The variety of possible light sources for photoATRP and simple operation endow this biosensor with great potential for practical applications.
Tuning of Oxidation Potential of Ferrocene for Ratiometric Redox Labeling and Coding of Nucleotides and DNA
Authors: Simonova Anna , Magriñá Ivan , Sýkorová Veronika , Pohl Radek , Ortiz Mayreli , Havran Luděk , Fojta Miroslav , O'Sullivan Ciara K. , Hocek Michal
Published: November 2019

Three sets of 7‐deazaadenine and cytosine nucleosides and nucleoside triphosphates bearing either unsubstituted ferrocene, octamethylferrocene and ferrocenecarboxamide linked through an alkyne tether to position 7 or 5, respectively, were designed and synthesized. The modified dNFcXTPs were good substrates for KOD XL DNA polymerase in primer extension and were used for enzymatic synthesis of redox‐labelled DNA probes. Square‐wave voltammetry showed that the octamethylferrocene oxidation potential was shifted to lower values, whilst the ferrocenecarboxamide was shifted to higher potentials, as compared to ferrocene. Tailed PEX products containing different ratios of Fc‐labelled A (dAFc) and FcPa‐labelled C (dCFcPa) were synthesized and hybridized with capture oligonucleotides immobilized on gold electrodes to study the electrochemistry of the redox‐labelled DNA. Clearly distinguishable, fully orthogonal and ratiometric peaks were observed for the dAFc and dCFcPa bases in DNA, demonstrating their potential for use in redox coding of nucleobases and for the direct electrochemical measurement of the relative ratio of nucleobases in an unknown sequence of DNA.
Role of actin in organelle trafficking in neurons
Authors: Venkatesh Keertana , Mathew Amal , Koushika Sandhya P.
Published: November 2019

Actin is a major cytoskeletal element involved in multiple cellular processes. Actin‐rich regions present along the neuronal process aid in neuronal function, mediating multiple events involved in organelle trafficking. Actin is involved in organelle biogenesis, transport, and anchoring at specific locations. These functions can potentially be regulated by actin in a myosin‐dependent or myosin‐independent manner. The actin network could aid in membrane remodeling through membrane constriction, motor dependent transport, polymerization‐based transport, cargo anchoring, and halting of cargo by acting as a physical barrier. Additionally, actin dynamics is perturbed in some neurodegenerative diseases where it could impact organelle biogenesis, transport, or anchoring thereby contributing to progression of disease phenotypes. The role of actin and myosin in organelle trafficking is the primary focus of this review.
Surveillance imaging for patients with head and neck cancer treated with definitive radiotherapy: A partially observed Markov decision process model
Authors: Ng Sweet Ping , Ajayi Temitayo , Schaefer Andrew J. , Pollard Courtney , Bahig Houda , Garden Adam S. , Rosenthal David I. , Gunn G. Brandon , Frank Steven J. , Phan Jack , Morrison William H. , Johnson Jason M. , Mohamed Abdallah S. R. , Sturgis Erich M. , Fuller Clifton D.
Published: November 2019

Background

A possible surveillance model for patients with head and neck cancer (HNC) who received definitive radiotherapy was created using a partially observed Markov decision process. The goal of this model is to guide surveillance imaging policies after definitive radiotherapy.

Methods

The partially observed Markov decision process model was formulated to determine the optimal times to scan patients. Transition probabilities were computed using a data set of 1508 patients with HNC who received definitive radiotherapy between the years 2000 and 2010. Kernel density estimation was used to smooth the sample distributions. The reward function was derived using cost estimates from the literature. Additional model parameters were estimated using either data from the literature or clinical expertise.

Results

When considering all forms of relapse, the model showed that the optimal time between scans was longer than the time intervals used in the institutional guidelines. The optimal policy dictates that there should be less time between surveillance scans immediately after treatment compared with years after treatment. Comparable results also held when only locoregional relapses were considered as relapse events in the model. Simulation results for the inclusive relapse cases showed that <15% of patients experienced a relapse over a simulated 36‐month surveillance program.

Conclusions

This model suggests that less frequent surveillance scan policies can maintain adequate information on relapse status for patients with HNC treated with radiotherapy. This model could potentially translate into a more cost‐effective surveillance program for this group of patients.
CoFEE: Context‐aware futuristic energy estimation model for sensor nodes using Markov model and autoregression
Authors: Theerthagiri Prasannavenkatesan
Published: November 2019

Nowadays, the emerging internet of things (IoT) technology offers the connectivity and communication between all things (various objects/things, devices, actuators, sensors, and mobile devices) at anywhere and anytime. These devices have embedded environment monitoring capabilities (sensors) and significant computational responsibilities. Most of the devices are working by utilizing their limited resources such as energy, memory, and bandwidth. Obviously, battery power is a crucial factor in any network. It makes tedious overheads to the network operations. Prediction of the future energy of the devices could be more helpful for managing resources, connectivity, and communication between the devices in IoT and wireless sensor networks (WSNs). It also facilitates the reliable internet and network connection establishment to the nodes. Hence, this paper presents an energy estimation model to predict the future energy of devices using the Markov and autoregression model. The proposed model facilitates smarter energy management among internet‐connected devices. Performance results show that the proposed method gives significant improvement compared with the neural network and other existing predictions. Further, the proposed model has very lower error performance metrics such as mean square error and computation overhead. The proposed model yields more perfect energy predictions for a node with 64% to 97% and 16% to 43% of higher prediction accuracy throughout the time series.
Epigenetic aging in children from a small‐scale farming society in The Congo Basin: Associations with child growth and family conflict
Authors: Gettler Lee T. , Lin David T. S. , Miegakanda Valchy , Lew‐Levy Sheina , Eick Geeta N. , Snodgrass J. Josh , MacIsaac Julia L. , Ramadori Katia E. , Kobor Michael S. , Boyette Adam H.
Published: November 2019

Developmental environments influence individuals' long‐term health trajectories, and there is increasing emphasis on understanding the biological pathways through which this occurs. Epigenetic aging evaluates DNA methylation at a suite of distinct CpG sites in the genome, and epigenetic age acceleration (EAA) is linked to heightened chronic morbidity and mortality risks in adults. Consequently, EAA provides insights on trajectories of biological aging, which early life experiences may help shape. However, few studies have measured correlates of children's epigenetic aging, especially outside of the U.S. and Europe. In particular, little is known about how children's growth and development relate to EAA in ecologies in which energetic and pathogenic stressors are commonplace. We studied EAA from dried blood spots among Bondongo children (n = 54) residing in a small‐scale, fisher‐farmer society in a remote region of the Republic of the Congo. Here, infectious disease burdens and their resultant energy demands are high. Children who were heavier for height or taller for age, respectively, exhibited greater EAA, including intrinsic EAA, which is considered to measure EAA internal to cells. Furthermore, we found that children in families with more conflict between parents had greater intrinsic EAA. These results suggest that in contexts in which limited energy must be allocated to competing demands, more investment in growth may coincide with greater EAA, which parallels findings in European children who do not face similar energetic constraints. Our findings also indicate that associations between adverse family environments and greater intrinsic EAA were nonetheless observable but only after adjustment for covariates relevant to the energetically and immunologically demanding nature of the local ecology.
Testing the performance of environmental DNA metabarcoding for surveying highly diverse tropical fish communities: A case study from Lake Tanganyika
Authors: Doble Christopher J. , Hipperson Helen , Salzburger Walter , Horsburgh Gavin J. , Mwita Chacha , Murrell David J. , Day Julia J.
Published: November 2019

Background and Aims

Environmental DNA (eDNA) metabarcoding provides a highly sensitive method of surveying freshwater fish communities, although studies to date have largely been restricted to temperate ecosystems. Due to limited reference sequence availability and challenges identifying closely related and rare species in diverse tropical ecosystems, the effectiveness of metabarcoding methods for surveying tropical fish communities from eDNA samples remains uncertain. To address this, we applied an eDNA metabarcoding approach to survey Lake Tanganyika's (LT) species‐rich littoral fish communities.

Materials and Methods

As this system contains many closely related species, particularly cichlid fishes, we used four primer sets including a cichlid‐specific primer set (Cichlid_CR). A reference database was built for the 12s, 16s, and control region for 358 fish species including over 93% of known cichlids.

Results and Discussion

In silico and in situ results demonstrated wide variability in the taxonomic resolution of assignments by each primer with the cichlid‐specific marker (Cichlid_CR) enabling greater species‐level assignments for this highly diverse family. A greater number of non‐cichlid teleost species were detected at sites compared to the visual survey data. For cichlid species however, sequencing depth substantially influenced species richness estimates obtained from eDNA samples, with increased depths producing estimates comparable to that obtained from the visual survey data.

Conclusions

Our study highlights the importance of sequencing depth and local reference databases when undertaking metabarcoding studies within diverse ecosystems, as well as demonstrating the potential of eDNA metabarcoding for surveying diverse tropical fish communities, even those containing closely related species within evolutionary radiations.
Expanding the Scope of Water‐Stable Rhenium(V)‐NHC Complexes – Synthesis, Characterization, and Derivatization
Authors: Bornemann Dustin , Schlemper Lukas , Trapp Nils , Togni Antonio
Published: November 2019

The synthesis of novel ReV–NHC oxo complexes bearing a tridentate scorpionate NHC ligand is reported. The complexes are accessible in a two‐step procedure from the precursor (NnBu4)[ReOCl4] by in situ deprotonation of the imidazolium salt 2,2‐bis(3‐methyl‐1H‐imidazol‐3‐ium‐1‐yl)acetate bromide (L1‐H2) using sodium hydride. The obtained complex [ReO(glyc)L1] (glyc = ethylene glycolato) is readily converted into [ReOCl2(L1)] which serves as starting material for the synthesis of water stable [ReO(L1)X] derivatives (X = dianionic ligand). In one case the formation of a Re dioxo species K2[ReO2(CN)2(L1)] was observed in aqueous conditions. All complexes were isolated, fully characterized and analyzed by XRD studies, demonstrating for the first time a coordination of scorpionate ligand L1 to rhenium. Additionally, their short‐ and long‐term stability in various aqueous media is an asset in view of developing new rhenium‐based metallodrugs.
Rh(III)‐Catalyzed Direct Amination of Aromatic Ketoximes Enabled by Potassium Acetate
Authors: Liu Lingling , Wang Ning , Dai Chenyang , Han Yi , Yang Shan , Huang Zhibin , Zhao Yingsheng
Published: November 2019

A method to achieve rhodium(III)‐catalyzed, potassium acetate enabled intermolecular C–H amination of ketoximes using various benzenesulfonamide, especially 4‐nitrobenzenesulfonamide is reported. Various aryl ketoximes substituted with electron‐withdrawing functional groups were all well tolerated and produced the corresponding products in moderate to good yields. A preliminary mechanistic study revealed that potassium acetate is essential to realizing intermolecular amination.
Effects of cold‐end temperature and heat load on the cooling characteristics of a pulse tube refrigerator
Authors: Liu Shaoshuai , Jiang Zhenhua , Ding Lei , Zhu Haifeng , Qu Xiaoping , Wu Yinong
Published: November 2019

A pulse tube refrigerator (PTR) was developed to operate at different cooling capacities to meet the requirements of various applications. Changes in the thermal loads or the long operating time of the PTR will influence the cold conditions (cold‐end temperature and heat load), leading to a deviation of the cooling performance from the optimal design conditions. The basic principles of the mass flow characteristics of the PTR are constructed based on enthalpy phase modulation, which is helpful for comprehending the relationships between cold‐end parameters and other parameters. A REGEN model is introduced in which different mass flows at the cold‐end are considered to simulate the effects of the cold‐end parameters on the performance of the regenerator. The influences of the cold‐end temperature and heat load on the cooling performance are investigated by using a coupling model of a DeltaEC model and a REGEN model. In addition, some experiments are performed on a PTR working at different cold‐end temperatures and heat load. The experimental results are in good agreement with the simulation results. The cooling performance of the PTR is influenced by the average pressure and operating frequency of different cooling states. Relative Carnot efficiencies of 12.2% for 4 W@60 K with a specific power of 33 W/W and 16.1% for 15 W @120 K with a specific power of 9 W/W can be achieved by the PTR using different operating parameters.
Study of ABPBI membrane as an alternative separator for vanadium redox flow batteries
Authors: Bhattacharyya Rama , Nayak Ratikanta , Ghosh Prakash C.
Published: November 2019

Vanadium redox flow batteries are receiving great attention due to their capabilities of offering multiscale energy‐storage and cross‐contamination‐free system. Ion‐exchange membrane (IEM), which is one of the critical components in the vanadium redox flow battery (VRFB) system, simultaneously prevents the cross‐mixing of active vanadium species, and facilitates the movement of the proton. The cross‐mixing of the vanadium species influences coulombic efficiency (CE), whereas the proton movement influences the voltage and energy efficiency (EE). Hence, IEM plays a major role in the performance of the battery in terms of self‐discharge rate, CE, crossover of active material, and ionic conductivity. In the present work, the suitability of an alternative low‐cost, efficient, and durable membrane, which are essential for providing a sustainable solution for VRFB, is studied. 2,5‐Polybenzimidazole membrane is studied as an alternative membrane and evaluated in a VRFB with mixed electrolyte, which has the potential to offer a substantial reduction in the cost. The mixed electrolyte helps in extending the operating temperature. 2,5‐Polybenzimidazole membrane‐based VRFB shows CE, EE, and voltage efficiency as 99%, 83%, and 84%, respectively, which is comparable to Nafion membrane.
Cumulative symbol optimization–based partial transmit sequence technique for PAPR reduction in low complexity GFDM system
Authors: Şimşir Şakir , Taşpınar Necmi
Published: November 2019

The new waveform called generalized frequency division multiplexing (GFDM), which has been increasing its popularity among the fifth generation (5G) waveform candidates day by day, is suggested very recently to meet the requirements of the next‐generation cellular systems. On the other hand, it is possible to generate and demodulate the GFDM signal with a less processing load by using low‐complexity GFDM (LC‐GFDM) system proposed shortly after the GFDM scheme. However, similar to the GFDM and the other multicarrier systems, high peak‐to‐average power ratio (PAPR) problem stands as one of the biggest obstacles, making difficulties for smooth communication in the LC‐GFDM system. In this system, the GFDM symbols obtained by the multiplication of time domain GFDM data sequences with circularly shifted prototype filter impulse responses are added together to achieve the transmission signal. Due to the related symbol addition process, direct application of the conventional partial transmit sequence (C‐PTS) technique, which was actually first developed for orthogonal frequency division multiplexing (OFDM), to the LC‐GFDM system without any modification will be useless. For this reason, we developed a new technique called cumulative symbol optimization–based partial transmit sequence (CSO‐PTS) for PAPR reduction in the LC‐GFDM system. In the simulations, the CSO‐PTS technique is compared to two different PAPR reduction methods called selective mapping and GreenOFDM. Simulation results evidently demonstrates that our novel proposal outperforms the other considered methods by ensuring quite efficient PAPR reduction, side lobe suppression, and bit error rate improvement in the LC‐GFDM system.
A new approach based on the modified FDS to numerically simulate cardboard box combustion under low pressure
Authors: Zhou Rui , Zhao Han , Ye Junjian , Zhang Hui
Published: November 2019

To solve the limitation of the fire test in high‐altitude areas only detecting a limited number of low‐pressure environments, in this paper, appropriate modifications of the FDS source codes were made to generate a new simulator program for low‐pressure applications. Standard fire experiments with different counts (1, 2, 18, and 27) of cardboard boxes were numerically simulated under different pressure levels (101, 90, 75, and 64 kPa). The computation data show consistent trends with the experimental results obtained in the low‐pressure tank at Lang Fang. Furthermore, the simulation results have been examined to show typical quantitative relationships: (a) The peak mass burning rate divided by the fire base dimension is correlated with the product of the pressure squared and the combustible characteristic length cubed. The exponential indices for the 1‐box fire, 18‐box fire, and 27‐box fire are 0.31, 0.29, and 0.29, respectively. (b) The heat release rate and mass burning rate show a good linearity at each fixed environmental pressure. In conclusion, the modified FDS is validated to work well under low‐pressure conditions, which can provide a receivable means to conduct low‐pressure fire simulation and analysis.
Identification of gene–environment interactions with marginal penalization
Authors: Zhang Sanguo , Xue Yuan , Zhang Qingzhao , Ma Chenjin , Wu Mengyun , Ma Shuangge
Published: November 2019

Gene–environment (G–E) interaction analysis has been extensively conducted for complex diseases. In marginal analysis, the common practice is to conduct likelihood‐based (and other “standard”) estimation with each marginal model, and then select significant G–E interactions and main effects based on p values and multiple comparisons adjustment. One limitation of this approach is that the identification results often do not respect the “main effects, interactions” hierarchy, which has been stressed in recent G–E interaction analyses. There is some recent effort tackling this problem, however, with very complex formulations. Another limitation of the common practice is that it may not perform well when regularization is needed, for example, because of “non‐normal” distributions. In this article, we propose a marginal penalization approach which adopts a novel penalty to directly tackle the aforementioned problems. The proposed approach has a framework more coherent with that of the recently developed joint analysis methods and an intuitive formulation, and can be effectively realized. In simulation, it outperforms the popular significance‐based analysis and simple penalization‐based alternatives. Promising findings are made in the analysis of a single‐nucleotide polymorphism and a gene expression data.
Human performance assessment of a single air traffic controller conducting multiple remote tower operations
Authors: Kearney Peter , Li Wen‐Chin , Zhang Jingyi , Braithwaite Graham , Wang Lei
Published: November 2019

The innovative concept of multiple remote tower operations (MRTO) can maximize cost savings by applying video panorama‐based remote tower working positions, which can facilitate fewer air traffic controllers (ATCO) to provide the air traffic services (ATS) function for more airports. Five subject‐matter experts, qualified remote tower ATCOs, participated in this research work by applying the human error template (HET) and comparing workload between physical tower operations and MRTO using NASA‐TLX (Task Load Index). The results demonstrate that augmented visualization provided sufficient technical support for a single ATCO to perform tasks originally designed to be performed by four ATCOs, however, the demands of the associated multiple tasks induced significant workload. There were significant differences in ATCOs’ mental demand, temporal demand, effort, and frustration between MRTO and physical tower operations. This innovative technology may induce human–computer interaction (HCI) issues that impact ATCO's perceived workload. This creates a need for further research on how to manage ATCO's workload in a multiple remote tower environment. This research work provided scientific evidence that MRTO can achieve the objectives of Single European Sky Air Traffic Management Research program. The findings can be applied to both ATCO training design and remote tower system design.
Factors influencing sweet drink consumption among preschool‐age children: A qualitative analysis
Authors: Chung Alexandra , Backholer Kathryn , Zorbas Christina , Hanna Lisa , Peeters Anna
Published: November 2019

Issue addressed

Consumption of high sugar foods and drinks are key risk factors for childhood obesity and dental decay. Sweet drinks are the single greatest contributor to the free sugars consumed by Australian children. Little is known about the factors influencing consumption of sweet drinks, particularly among preschool‐age children.

Methods

Focus groups and semi‐structured interviews conducted with parents and grandparents (n = 25) residing in different socio‐economic areas across metropolitan and regional Victoria, Australia. Thematic analysis identified the factors influencing sweet drink consumption, which were then aligned with the socio‐ecological model.

Results

At an individual level, health knowledge, health beliefs, and parenting skills and confidence influenced drink choices. At the social level, peer and family influence, and social and cultural norms emerged as influential. At the environmental level, sweet drink availability, targeted marketing, drink prices and settings‐based policies influenced drink choices. Strategies identified by participants to support healthier drink choices included health education at the individual level; positive role modelling at the social level; and restricting unhealthy marketing, improved access to water, decreased availability of sweet drinks and price modification at the environmental level.

Conclusion

Sweet drink consumption among preschool‐age children is influenced by multiple factors across all domains of the socio‐ecological model. Parents and grandparents are calling for education, healthy environments and supportive policies.

So what?

In contrast to common rhetoric, children's sweet drink consumption is often influenced by factors beyond parental control. A multi‐component strategy is required to support parents and grandparents in their efforts to make healthy choices for their children.
Long non‐coding RNA FENDRR restrains the aggressiveness of CRC via regulating miR‐18a‐5p/ING4 axis
Authors: Yin Sheng Lu , Xiao Fei , Liu Yong Fu , Chen Hao , Guo Guan Cheng
Published: November 2019

There is increasing evidence has indicated that long non‐coding RNAs (lncRNAs) are implicated in the tumorigenesis and development of colorectal cancer (CRC). Nevertheless, the clinical significances and functions of FENDRR in CRC remain unknown. In this study, we reveal that lncRNA FENDRR is downregulated in CRC and negatively correlated with advanced stage and poor clinical outcomes of patient with CRC. Overexpression of FENDRR represses the proliferation, migrate and invasive capacities of CRC cell in vitro, and upregulation of FENDRR inhibits the growth and distant metastatic capacity of CRC cell in vivo. Mechanistically, FENDRR interacts with miRNA‐18a‐5p (miR‐18a‐5p) and subsequently regulates the expression of inhibitor of growth 4 (ING4) in CRC cell. Interestingly, ING4 repression or miR‐18a‐5p rescues FENDRR induced proliferation and aggressive phenotypes inhibition of CRC cell. Altogether, our findings suggest that FENDRR exerts an inhibitory role in CRC by interacting with miR‐18a‐5p and future increases ING4 expression.
Distribution of serum amyloid A and establishment of reference intervals in healthy adults
Authors: Liu Qian , Li Yan , Yang Fumeng , Xu Tongdao , Yao Li , Sun Jin , Liang Wei
Published: November 2019

Background

Serum amyloid A (SAA) plays a critical role in acute or chronic and is used in clinical laboratories as an indicator of inflammation. The elevated SAA is closely related to inflammation‐mediated diseases, such as liver diseases, autoimmune diseases, metabolism‐related diseases, amyloidosis, and tumors. However, there is no unified population reference interval for SAA. This study aimed to investigate the distribution of SAA in healthy Chinese adults 20‐79 years of age and to establish its population reference interval.

Methods

A total of 2365 healthy subjects met the requirements of this study. The levels of SAA were detected using an AU5821 automatic biochemical analyzer and its original reagents. According to the recommended methods of CLSI C28‐A3 and WS/T 402‐2012, the population reference interval of SAA was established using the unilateral 95th percentile (P95), and the 90% confidence interval of upper limits was calculated.

Results

The distributions of SAA levels were not significantly different between sexes (P> .05) and also did not differ by age (P> .05). Therefore, the population reference interval for SAA was established as an upper limit of 11.0 mg/L (90% confidence interval: 9.3‐12.3 mg/L) by using the method of latex immunoturbidimetry.

Conclusions

Serum amyloid A is closely related to the occurrence and progression of various diseases. The preliminary establishment of a population reference interval for SAA can fully exert its potential clinical value.
Early prenatal detection of anterior uterine sacculation resulting from previous cesarean sections
Authors: Traisrisilp Kuntharee , Bootchaingam Phenphan , Sreshthaputra Opas , Tongsong Theera
Published: November 2019

Anterior uterine sacculation was diagnosed at 15 weeks of gestation in a woman with two previous cesarean sections, based on hourglass appearance of two distinct uterine segments, namely the empty upper segment and the large thinned wall lower segment containing a fetus with posteriorly attached placenta. The pregnancy developed through the bulging weakened anterior wall instead of growing toward the upper segment. Urgent hysterectomy was performed. The operative and pathological findings confirmed the prenatal ultrasound findings. This is the first report of prenatal diagnosis of sacculation due to cesarean section, which prevented the catastrophic event of uterine rupture.
Leadership in a Constant Liminal Loop: How can i be Authentic when i don't know who i am?
Authors: Donaldson William , Harter Nathan
Published: November 2019

The search for leader authenticity implies that somewhere there is a true self. Yet the self, like anything else, is constantly changing, passing through a series of liminal phases. Authenticity, therefore, would capture the liminal condition within which all leaders operate. What this process yields, however, is a web of paradoxes, such as the need to stabilize while remaining open to a shifting reality and interpreting that reality at both the micro and the macro levels in a never‐ending loop known as the hermeneutic circle. Only a complex and fluid leader can cope with a complex and fluid reality. Fortunately, the literature presents a conceptual toolkit, including Boyd's OODA loop, paradoxical thinking, design thinking, and systems thinking–gathered in this article to assist the leader whose authentic self is always a work in progress.
Development and validation of a model for hepatitis B e antigen seroconversion in entecavir‐treated patients with chronic hepatitis B
Authors: Shen Sheng , Wong Grace L.‐H. , Kuang Zhe , van Campenhout Margo J. H. , Fan Rong , Wong Vincent W.‐S. , Yip Terry C.‐F. , Chi Heng , Liang Xieer , Hu Xiaoyun , Lin Weiyin , Wu Yaobo , Liu Xiaoju , Boonstra André , Hou Jinlin , Sun Jian , Chan Henry L.‐Y.
Published: November 2019

Achieving hepatitis B e antigen (HBeAg) seroconversion is a satisfactory endpoint during antiviral treatment for chronic hepatitis B (CHB). This study aimed to develop and validate a novel scoring system to predict HBeAg seroconversion during entecavir (ETV) treatment. A total of 526 patients with HBeAg‐positive CHB treated with ETV for at least 1 year were randomly assigned to the training and validation cohorts. Baseline parameters including hepatitis B virus DNA, hepatitis B surface antigen (HBsAg), hepatitis B core antibody (HBcAb), and alanine aminotransferase level were quantified. Patients who achieved HBeAg seroconversion were compared with those without HBeAg seroconversion. A prediction model was established to predict HBeAg seroconversion during ETV treatment. After a median follow up of 2.67 years, 93 (36.0%) and 87 (32.5%) patients in the training and validation cohorts developed HBeAg seroconversion. A prediction score composed of age, HBsAg and HBcAb quantification was derived. Areas under receiver operating characteristic curve at 5 years of this prediction score were 0.70 and 0.72 in the training and validation cohorts. By using the dual cutoff values of 0.28 and 0.58, the model was endowed with high sensitivity and specificity to exclude or identify patients developing HBeAg seroconversion (90.3% sensitivity and 90.2% specificity in the training cohort as well as 92.8% sensitivity and 84.4% specificity in the validation cohort, respectively). A novel prediction score that uses baseline clinical variables was developed and validated. The score accurately estimates the probabilities of developing HBeAg seroconversion at 5‐years ETV therapy in patients with CHB.
ChIP‐seq analysis of Brucella reveals transcriptional regulation of GntR
Authors: Li Zhiqiang , Li Min , Zhang Hui , Wang Shuli , Xi Li , Zhang Xiaogen , Yi Jihan , Zhang Huan
Published: November 2019

Transcriptional regulator GntR controls diverse physiological functions necessary for Brucella survival. In the intracellular pathogen Brucella, GntR has been shown to regulate the expression of genes related to virulence. However, the precise determination of GntR direct targets has so far proved elusive. Therefore, we performed chromatin immunoprecipitation of GntR10 followed by next‐generation sequencing (ChIP‐seq). We selected target gene BAB1_1163 directly regulated by GntR10 and created the mutant (2308Δ1163) from virulent Brucella abortus 2308 (S2308). 2308Δ1163 strain survival capability in murine macrophages (RAW 264.7) was detected and the levels of tumor necrosis factor‐α (TNF‐α) and interleukin‐1β (IL‐1β) were also measured. We detected 88 intergenic ChIP‐seq peaks of GntR10 binding distributed across the Brucella genome and determined a markedly asymmetric binding consensus motif with 12 bp length. 2308Δ1163 showed reduced survival capability in RAW 264.7. After the macrophages were infected with 2308Δ1163, the levels of TNF‐α and IL‐1β were decreased and were significantly lower than that for the S2308‐infected group, indicating that the 2308Δ1163 mutant could inhibit the secretion of inflammatory cytokines. Taken together, the research has recorded valuable data about GntR10 and provided new insights into the functionality of GntR10.
Ultra high performance liquid chromatography method development for separation of omeprazole and related substances on core‐shell columns using a Quality by Design approach
Authors: Johansson Emma , Karlsson Anders , Ludvigsson Jufang Wu
Published: November 2019

An updated and improved method for analysis of omeprazole/esomeprazole and related substances on core‐shell columns was developed using Fusion LC Method Development™. The method was optimized with respect to column type, column temperature, mobile phase pH level, and gradient time. Four different core‐shell columns were examined to develop a method suitable for both high performance‐ and ultra‐high performance liquid chromatography using a Quality by Design approach. The final method offers two alternative columns: Poroshell EC C18 (3.0 × 100 mm, 2.7 µm) or Poroshell HPH (3.0 × 100 mm, 2.7 µm) with the same gradient elution condition and mobile phase composition. Total run time is 18 min with 12 min of gradient elution. Phosphate buffer (15 mM, pH 7.8) is selected as the aqueous mobile phase and acetonitrile as the organic mobile phase. Column temperature is set at 40°C and ultraviolet detection at 302 nm. Furthermore, by studying parameters in a systematic way, an understanding of the effect of the input parameters enhances the method robustness and should allow for regulatory flexibility in terms of post‐approval changes. Compared to the current United States Pharmacopeia method, the updated method is faster, more efficient and performs well above acceptance criteria.
Ultrasound Doppler Flow in Patients With Chronic Midportion Achilles Tendinopathy: Is Surface Area Quantification a Reliable Method?
Authors: van der Vlist Arco C. , Veen Jasper M. , van Oosterom Robert F. , van Veldhoven Peter L. J. , Verhaar Jan A. N. , de Vos Robert‐Jan
Published: November 2019

Objectives

Ultrasound assessments of patients with chronic midportion Achilles tendinopathy include determining the degree of neovascularization using Doppler flow. A frequently used measure to quantify neovascularization is the modified Öhberg score. It is unknown whether the semiquantitative modified Öhberg score (0–4+) has higher reliability than a quantified measure of Doppler flow (0–100%). The purpose of this cross‐sectional study was to evaluate the interobserver reliability of the modified Öhberg score and a surface area quantification (SAQ) method for Doppler flow in patients with chronic midportion Achilles tendinopathy.

Methods

Two observers examined the degree of Doppler flow independently using SAQ and the modified Öhberg score during a single consultation. The intraclass correlation coefficient, standard error of measurement, and minimal detectable difference were determined to evaluate the reliability and measurement properties of the SAQ method and the modified Öhberg score.

Results

In total, 28 consecutive patients with chronic midportion Achilles tendinopathy participated. The intraclass correlation coefficient for interobserver reliability of the SAQ method was 0.81 (95% confidence interval, 0.58–0.91), compared to 0.64 (95% confidence interval, 0.45–0.81) for the modified Öhberg score. The standard error of measurement and minimal detectable difference values for the SAQ method were 2.9% and 8.0%, respectively, and for the modified Öhberg score, they were 0.55 and 1.53 points.

Conclusions

The SAQ method shows good reliability to evaluate the degree of Doppler flow in patients with chronic midportion Achilles tendinopathy, and it overcomes the ceiling effect of the modified Öhberg score. Future research should focus on the relationship between the SAQ method and clinical outcomes and use this method to monitor treatment responses.
Application of Contrast‐Enhanced Real‐time 3‐Dimensional Ultrasound in Solid Abdominal Organ Trauma
Authors: Feng Cong , Wang Libo , Huang Sai , Wang Lili , Zhou Xuan , Cui Xiang , Chen Li , Lv Faqin , Li Tanshi
Published: November 2019

Objectives

To determine whether real‐time 3‐dimensional ultrasound (RT3DUS) could provide additional information on early detection and evaluation in the management of solid abdominal organ trauma based on an animal model.

Methods

Nine bleeding lesions were developed in the livers (n = 3), kidneys (n = 3), and spleens (n = 3) from 9 pigs. An ultrasound contrast agent was administered intravenously (liver, 0.025 mL/kg; kidney, 0.008 mL/kg; and spleen, 0.013 mL/kg) after an unenhanced 2‐dimensional ultrasound (2DUS) examination (B‐mode and color Doppler). After contrast agent injection, bleeding lesions were imaged by 2DUS and sequentially imaged by 3‐dimensional static ultrasound (3DSUS) and RT3DUS to identify active bleeding, observe the relationship between bleeding lesions and peripheral blood vessels, and evaluate the spatial scope of the bleeding lesions in the organs.

Results

For the identification of active bleeding, there was no statistical difference in contrast‐enhanced 2DUS, 3DSUS, and RT3DUS. For observation of the relationship between bleeding lesions and peripheral blood vessels, RT3DUS performed statistically better than 2DUS (P < .05), as reconstructed RT3DUS could show more information about the relationship. For the evaluation of the spatial scope of the bleeding lesion in the organ, RT3DUS also performed statistically better than 2DUS from the multiplanar observation by postprocessing of the 3‐dimensional real‐time volumes (P < .05).

Conclusions

Real‐time 3‐dimensional ultrasound improves early detection and evaluation of solid abdominal organ trauma and provides additional information over the current contrast‐enhanced 2DUS.
Increased Brachial Artery Compliance After Arteriovenous Fistula Creation as Measured by Shear Wave Elastography: Results From a Feasibility Study
Authors: MacDonald Conor‐James , Ross Rose , Houston John Graeme
Published: November 2019

Objectives

Arterial stiffness has been proposed as a marker of arteriovenous fistula failure and can be measured locally by using ultrasound shear wave elastography (SWE). This preliminary study aimed to assess whether SWE measurements of the brachial artery were associated with arteriovenous fistula failure.

Methods

Data were collected on patients who were indicated for fistula creation. Preoperative and postoperative vessel diameters from B‐mode ultrasound, brachial artery SWE maps, and demographic data were collected. Logistic and linear regression analyses were used to determine whether any of these variables were related to the outcome of the fistula 3 months after creation.

Results

Data were acquired for 33 patients. Shear wave velocity values decreased after fistula creation (mean ± SD, –1.2 ± 1 m/s; P < .05). No parameters were associated with failure of the fistula in the logistic regression analysis.

Conclusions

No markers were related to fistula failure, but a decrease in the shear wave velocity was observed in the brachial arteries after fistula creation, indicating increased compliance.
Technological intensity as a moderating variable for the intellectual capital–performance relationship
Authors: Palazzi Federica , Sgrò Francesca , Ciambotti Massimo , Bontis Nick
Published: November 2019

The purpose of this study is to provide empirical evidence of the moderating influence of technology intensity on the relationship between intellectual capital (IC) and corporate performance in Italian small‐ and medium‐sized enterprises (SMEs). An empirical analysis was developed for the period 2012–2016 and included 62,849 Italian SMEs. Data were collected from the AIDA database (Bureau Van Dijk—A Moody's Analytics Company), and the sample was composed of high‐tech, medium‐high‐tech, medium‐low‐tech, and low‐technology manufacturing firms, according to the “Classification of Manufacturing Industries by Technological Intensity,” as defined by the OECD. The empirical results highlight that profitability is significantly and positively affected by financial and physical capital efficiency and by human capital efficiency (HCE), but the effect of HCE is weak, and the structural capital efficiency has a negative effect on corporate performance. The time variables positively affect corporate performance, with the highest coefficient in 2016. Additionally, technology intensity reinforces the positive effect of HCE on firm performance: the higher the technological intensity, the higher the positive impact of HCE on corporate performance. The managerial implications are relevant; in fact, tangible, financial, and current assets (employed capital) represent the principal lever of performance for managers in technology sectors. The negative effect of structural capital could be caused by inefficient use of this resource, or the employed variable could not be adequate to effectively measure this IC component. It is necessary for managers to appreciate technological intensity as a contingency variable affecting the IC–performance relationship.
A novel similar habitat potential model based on sliding‐window technique for vegetation restoration potential mapping
Authors: Zhang Daojun , Xu Xin , Yao Shunbo , Zhang Jinting , Hou Xianhui , Yin Runsheng
Published: November 2019

Vegetation restoration potential mapping (VRPM) is of great importance for regional ecosystem restoration planning after long‐term land degradation or short‐term disasters. However, there are some problems to be solved in the current models for evaluating the potential of vegetation restoration. First, the models for VRPM are mostly established based on a knowledge‐driven index system. Although this kind of model is logically rigorous, it relies too much on expert knowledge and is relatively inefficient, especially for large‐area vegetation restoration assessments. Second, because of the spatial heterogeneity, as well as the absence of important indicators, the traditional global‐based evaluation models are difficult to adapt to the entire study area. In this study, an improved data‐driven approach, that is, a sliding‐window based similar habitat potential model, is developed for VRPM. The advantages of the new model include: (a) it is more efficient in determining the importance of each influencing factor without resorting to expert knowledge; (b) it is more locally adaptive than the global model because it performs sample training, rule building, and vegetation restoration potential calculation in each current local window. We provide a case‐study to show the modeling process and result interpretation of the new model.
Automated production processes in the rotor blade industry – Solutions for a continuous direct textile layup
Authors: Franke J. , Ohlendorf J.‐H. , Thoben K.‐D.
Published: November 2019

Recent efforts concerning the automation of production processes for wind turbine rotor blades involve several new challenges. The technical fabrics used present specific features in handling due to their limp characteristics. Because of the steady growth of modern offshore wind turbine dimensions, larger rotor blade mold surfaces have to be covered with technical fabrics which influence the size and the weight of the handling systems used for automation. For an economic production of future wind turbine types, an increase in efficiency – by shortening the process cycle times – is crucial. Consequently, the time‐consuming process steps need to be automated. The article focuses on the continuous direct textile layup process and delivers ideas and solutions for the resulting challenges of process steps like storing, cutting and draping a technical textile in an automated rotor blade production.
Modeling of the ductile damage – Application for bar shearing
Authors: Moakhar S. , Hentati H. , Barkallah M. , Louati J. , Haddar M. , Bonk C. , Behrens B.A.
Published: November 2019

The finite element method is becoming a reliable tool for designing manufacturing processes. Even in bar shearing, which is a basic operation in the metalworking industry, the finite element method is increasingly employed for the optimization of the process. Ductile damage modeling is crucial thereby. Recent experimental investigations have shown that, in particular, triaxiality and temperature must be considered in the constitutive description of damage in the shear zone. In this context, the Hooputra's criterion is in this work applied for the numerical simulation of shearing taking account of different stress states and temperatures. The parameterization of the model is based on wide experimental investigations. Characterization tests on smooth and notched cylindrical specimens as well as on flat shear specimens are carried out. The selected material for this investigation is the aluminum alloy AW6082. Subsequently, the numerical calculation of shearing is performed. By comparing the simulation results with data from experimental shearing, the importance of the consideration of the temperature gradients and the different triaxiality values in the shear zone is proven.
Creep properties of a U‐type notch plate in Ni‐based superalloy
Authors: Gan W. , Wen Z. , Pei H. , Gao H.
Published: November 2019

In the present investigation, the effect of notch on creep rupture behavior and creep rupture life of a Ni‐based superalloy has been assessed by performing creep tests on smooth and U‐notched plate specimen under 0°C. The finite element analysis coupled with continuum damage mechanics are carried out to understand the stress distribution across the notch throat and the creep damage evolution under multi‐axial stress state. The creep rupture life of U‐notched specimen is much larger than that of plane plate specimen under the same stress condition, indicating that there is a strengthening effect on notch specimen. Creep rupture life increases with increasing the notch radius, the smaller notch radius can induce the creep rupture easier. The effect of notch on the creep damage is also studied. It is found that the location of the maximum creep damage and the maximum equivalent creep strain initiates first at the notch root and gradually moves to the inside as the notch radius increases.