bluuebunny/crossref_metadata_2025 huggingface dataset:
Nutrients and micronutrients at risk during renal replacement therapy: a scoping review
Authors: Berger Mette M. , Broman Marcus , Forni Lui , Ostermann Marlies , De Waele Elisabeth , Wischmeyer Paul E.
Published: May 2021

Purpose of review

Malnutrition is frequent in patients with acute kidney injury. Nutrient clearance during renal replacement therapy (RRT) potentially contributes to this complication. Although losses of amino acid, trace elements and vitamins have been described, there is no clear guidance regarding the role of micronutrient supplementation.

Recent findings

A scoping review was conducted with the aim to review the existing literature on micronutrients status during RRT: 35 publications including data on effluent losses and blood concentrations were considered relevant and analysed. For completeness, we also included data on amino acids. Among trace elements, negative balances have been shown for copper and selenium: low blood levels seem to indicate potential deficiency. Smaller size water soluble vitamins were found in the effluent, but not larger size liposoluble vitamins. Low blood values were frequently reported for thiamine, folate and vitamin C, as well as for carnitine. All amino acids were detectable in effluent fluid. Duration of RRT was associated with decreasing blood values.

Losses of several micronutrients and amino acids associated with low blood levels represent a real risk of deficiency for vitamins B1 and C, copper and selenium: they should be monitored in prolonged RRT. Further Research is urgently required as the data are insufficient to generate strong conclusions and prescription recommendations for clinical practice.
Best case/worst case for the trauma ICU: Development and pilot testing of a communication tool for older adults with traumatic injury
Authors: Zimmermann Christopher J. , Zelenski Amy B. , Buffington Anne , Baggett Nathan D. , Tucholka Jennifer L. , Weis Holly B. , Marka Nicholas , Schoultz Thomas , Kalbfell Elle , Campbell Toby C. , Lin Vivian , Lape Diane , Brasel Karen J. , Phelan Herbert A. , Schwarze Margaret L.
Published: May 2021

BACKGROUND

“Best Case/Worst Case” (BC/WC) is a communication tool to support shared decision making in older adults with surgical illness. We aimed to adapt and test BC/WC for use with critically ill older adult trauma patients.

METHODS

We conducted focus groups with 48 trauma clinicians in Wisconsin, Texas, and Oregon. We used qualitative content analysis to characterize feedback and adapted the tool to fit this setting. Using rapid sequence iterative design, we developed an implementation tool kit. We pilot tested this intervention at two trauma centers using a pre-post study design with older trauma patients in the intensive care unit (ICU). Main outcome measures included study feasibility, intervention acceptability, quality of communication, and clinician moral distress.

RESULTS

BC/WC for trauma patients uses a graphic aid to document major events over time, illustrate plausible scenarios, and convey uncertainty. We enrolled 86 of 116 eligible patients and their surrogates (48 pre/38 postintervention). The median patient age was 72 years (51–95 years) and mean Geriatric Trauma Outcome Score was 126.1 (±30.6). We trained 43 trauma attendings and trauma fellows to use the intervention. Ninety-four percent could perform essential tool elements after training. The median end-of-life communication score (scale 0–10) improved from 4.5 to 6.6 (p = 0.006) after intervention as reported by family and from 4.1 to 6.0 (p = 0.03) as reported by nurses. Moral distress did not change. However, there was improvement (less distress) reported by physicians regarding “witnessing providers giving false hope” from 7.34 to 5.03 (p = 0.022). Surgeons reported the tool put multiple clinicians on the same page and was useful for families, but tedious to incorporate into rounds.

CONCLUSION

BC/WC trauma ICU is acceptable to clinicians and may support improved communication in the ICU. Future efficacy testing is threatened by enrollment challenges for severely injured older adults and their family members.

LEVEL OF EVIDENCE

Therapeutic, level III.
The timing of amputation of mangled lower extremities does not predict post-injury outcomes and mortality: A retrospective analysis from the ACS TQIP database
Authors: Tillmann Bourke W. , Guttman Matthew P. , Nathens Avery B. , de Mestral Charles , Kayssi Ahmed , Haas Barbara
Published: May 2021

BACKGROUND

While limb salvage does not result in improved functional outcomes among patients with a mangled lower extremity, the impact of attempted limb salvage on mortality and complications is poorly understood. The objective of this study was to evaluate the relationship between attempted limb salvage and in-hospital outcomes among patients with a mangled lower extremity.

METHODS

We performed a retrospective cohort study of adults, 16 years or older, with a mangled lower extremity. Data were derived from the American College of Surgeons’ Trauma Quality Improvement Program (2012–2017). We compared mortality, complications (severe sepsis, acute kidney injury [AKI], decubitus ulcers) and length of stay between patients managed with the intention of limb salvage (amputation beyond 24 hours or no amputation) and those who underwent early amputation (within 24 hours of presentation). Instrumental variable analysis was used to evaluate the relationship between management strategy and outcomes.

RESULTS

We identified 5,527 patients with a mangled lower extremity, of which 901 (16.3%) underwent early amputation. Among those managed with attempted limb salvage, 42.5% underwent amputation prior to discharge. After adjusting for patient and hospital characteristics, there was no association between initial management strategy and mortality (odds ratio, 1.20; 95% confidence interval [CI], 0.83–1.74 early amputation vs. attempted limb salvage). Early amputation was associated with lower odds of AKI (OR, 0.59; 95% CI, 0.39–0.88) and a trend toward shorter length of stay (relative risk, 0.77; 95% CI, 0.52–1.14).

CONCLUSION

Over half of patients who sustain a mangled lower extremity undergo amputation during their initial hospital course. While a limb salvage strategy is associated with an elevated risk of AKI, there is no association between attempted limb preservation and mortality. These findings suggest that in patients in which there is no clear indication for early amputation, attempts at limb salvage do not come at the cost of increased mortality.

LEVEL OF EVIDENCE

Therapeutic study, level IV.
The Electrophysiological Findings in Spinocerebellar Ataxia Type 6: Evidence From 24 Patients
Authors: Zhang WenWen , Jasinarachchi Mahi , Seiderer Linda , Szmulewicz David J. , Roberts Leslie J.
Published: May 2021

Purpose:

Peripheral neuropathy has been reported commonly in several spinocerebellar ataxia (SCA) types. To date, there is a lack of robust evidence for neuropathy or neuronopathy in SCA type 6 (SCA6). Here, we aim to evaluate the presence of neuropathy or neuronopathy in a cohort of SCA6 patients.

Methods:

Twenty-four individuals with genetically confirmed SCA6 underwent detailed neurophysiological assessment. This included nerve conduction studies, and in some, cutaneous silent periods, blink reflexes, tilt table tests, quantitative sudomotor axon reflex tests, and somatosensory (median and tibial) evoked potentials.

Results:

Mean age was 56.1 years (range, 22–94 years) at the time of testing. Four patients were presymptomatic of SCA6 at recruitment. The mean disease duration of symptomatic patients was 11.9 years (range, 1–40 years). Most patients (79.2%, 19/24) had no neurophysiological evidence of a peripheral neuropathy. One with impaired glucose tolerance had mild, large, and small fiber sensorimotor polyneuropathy. One elderly patient had length-dependent axonal sensorimotor polyneuropathy. Two had minor sensory abnormalities (one had type II diabetes and previous chemotherapy). One other had minor small fiber abnormalities. Ten patients (41.7%) had median neuropathies at the wrist. All somatosensory evoked potential (15/15), and most autonomic function tests (13/14) were normal.

Conclusions:

A large proportion of subjects (79.2%) in our cohort had no evidence of large or small fiber neuropathy. This study does not support the presence of neuropathy or neuronopathy as a common finding in SCA6 and confirms the importance of considering comorbidities as the cause of neurophysiological abnormalities.
Frailty variation models for susceptibility and exposure to SARS-CoV-2
Authors: Gomes M. Gabriela M. , Ferreira Marcelo U. , Chikina Maria , Pegden Wesley , Aguas Ricardo
Published: May 2021

Individual variation in susceptibility and exposure is subject to selection by force of infection, accelerating the natural acquisition of immunity, and reducing herd immunity thresholds and epidemic final sizes. This is a manifestation of a wider population phenomenon known as “frailty variation” in demography. Despite this theoretical understanding, public health policies continue to be guided by mathematical models that leave out most of the relevant variation and as a result inflate projected infection burdens. Here we focus on the trajectories of the coronavirus disease (COVID-19) pandemic in England and Scotland. We fit models to series of daily deaths and estimate relevant epidemiological parameters, including coefficients of variation which we find in agreement with direct measurements based on published contact surveys. Our estimates are robust to whether the data series encompass one or two pandemic waves. We conclude that herd immunity thresholds are being reached with a larger contribution of vaccination in Scotland than in England, where naturally acquired immunity is higher. These results are relevant to global vaccination policies.
Assessment of N95 respirator for reuse after sterilization: filtration efficacy, breathing resistance, quality factor, chemical structure and surface charge density
Authors: Kumar Amit , Subramanian V. , Shailesh J. , Venkatraman B.
Published: May 2021

In the present ongoing pandemic, the N95 respirator is an essential protective barrier to suppress the spread of the SARS-Cov-2 virus and protect the frontline worker from exposure. The N95 respirators are meant for single usage; however, they can be used after decontamination in-light of the economy and shortfall in availability. At this juncture, the respirators performance after various types of sterilization and usage condition is required to be analyzed in detail. With this motto, this work has proceeded. The filtration efficiency, pressure drop, and quality factor of the respirator are evaluated for two face velocities (5.8 and 26.4 cm/s) following different sterilization methods. Sterilization techniques used here are dry air oven heating, gamma irradiation, and immersing in a 10% concentration of liquid hydrogen peroxide. The particle filtration performance and electrostatic surface charge density measurement are used to determine the facemasks efficacy after sterilization. The methods recommended to sterilize N95 masks without affecting their performance are (i) using dry air heat at 80°C and (ii) H2O2soaking. The highest reduction in filtration efficiency is observed to be 30-35% after gamma irradiation due to a change in the electrostatic properties of the respirator layers. However, the filtration efficiency does not change significantly for other sterilization methods despite a change in charge density, but there is no direct correlation with filtration efficiency. Electrostatic charge measurement of the filtration layer is a crucial indicator of filtration efficiency degradation. Policymakers can use these data during potential future N95 shortage to assess the viability of sterilization methods.
Comparative Transcriptomics Identifies Potential Stemness-Related Markers for Mesenchymal Stromal/Stem Cells
Authors: Ghabriel Myret , El Hosseiny Ahmed , Moustafa Ahmed , Amleh Asma
Published: May 2021

Mesenchymal stromal/stem cells (MSCs) are multipotent cells residing in multiple tissues with the capacity for self-renewal and differentiation into various cell types. These properties make them promising candidates for regenerative therapies. MSC identification is critical in yielding pure populations for successful therapeutic applications; however, the criteria for MSC identification proposed by the International Society for Cellular Therapy (ISCT) is inconsistent across different tissue sources. In this study, we aimed to identify potential markers to be used together with the ISCT’s criteria to provide a more accurate means of MSC identification. Thus, we carried out a comparative analysis of the expression of human and mouse MSCs derived from multiple tissues to identify the common differentially expressed genes. We show that six members of the proteasome degradation system are similarly expressed across MSCs derived from bone marrow, adipose tissue, amnion, and umbilical cord. Also, with the help of predictive models, we found that these genes successfully identified MSCs across all the tissue sources tested. Moreover, using genetic interaction networks, we showed a possible link between these genes and antioxidant enzymes in the MSC antioxidant defense system, thereby pointing to their potential role in prolonging the life span of MSCs. Our results suggest that these genes can be used as stemness-related markers.
Short single-stranded DNA with putative non-canonical structures comprises a novel class of plasma cell-free DNA
Authors: Hisano Osamu , Ito Takashi , Miura Fumihito
Published: May 2021

Cell-free DNA (cfDNA) in human blood is currently investigated as a minimally invasive, highly informative biomarker. Here, we aimed to investigate the existence of the shorter cfDNA fragments in the blood. Using an improved cfDNA purification protocol and a 3′-end-labeling method, we found DNA fragments of approximately 50 nucleotides in human plasma, present at a molar concentration comparable to that of the nucleosome-sized fragments. These short fragments cannot be recovered by widely used cfDNA isolation methods, and are composed of single-stranded DNA (ssDNA), thus escaping detection in previous studies. We established a library-preparation protocol based on our unique ssDNA ligation technique and applied it to the isolated cfDNA. Deep sequencing of these libraries revealed that the short fragments are derived from hundreds of thousands of genomic sites in open chromatin regions and enriched with transcription factor-binding sites. Remarkably, antisense strands of putative G-quadruplex motifs occupy as much as one-third of peaks called with these short fragments. Hence, we propose a novel class of plasma cfDNA composed of short single-stranded fragments that potentially form non-canonical DNA structures.
Sorption of neuropsychopharmaca in microfluidic materials for in-vitro studies
Authors: Winkler Thomas E. , Herland Anna
Published: May 2021

Sorption (i.e., ad- & ab-sorption) of small-molecule compounds to polydimethylsiloxane (PDMS) is widely acknowledged. However, studies to date have largely been conducted under atypical conditions for microfluidic applications (lack of perfusion, lack of biological fluids); especially considering the biological studies such as Organs-on-Chips where small-molecule sorption poses the largest concern. Here, we present the first study of small-molecule sorption under relevant conditions for microphysiological systems, focusing on a standard geometry for biological barrier studies that find application in pharmacokinetics. We specifically assess the sorption of a compound panel including 15 neuropsychopharmaca at in-vivo concentration levels. We consider devices constructed from PDMS as well as two material alternatives (off-stoichiometry thiol-ene-epoxy, or tape/polycarbonate laminates). Moreover, we study the much-neglected impact of peristaltic pump tubing, an essential component of the recirculating systems required to achieve in-vivo-like perfusion shear stresses. We find that choice of device material does not significantly impact sorption behavior in our barrier-on-chip-type system. Our PDMS observations in particular suggest that excessive compound sorption observed in prior studies is not sufficiently described by compound hydrophobicity or other suggested predictors. Critically, we show that sorption by peristaltic tubing, including the commonly-utilized PharMed BPT, dominates over device sorption even on an area-normalized basis, let alone at the typically much larger tubing surface areas. Our findings highlight the importance of validating compound dosages in Organ-on-Chip studies, as well as the need for considering tubing materials with equal or higher care than device materials.
Actin dynamics as a multiscale integrator of cellular guidance cues
Authors: Bull Abby L. , Campanello Leonard , Hourwitz Matt J. , Yang Qixin , Zhao Min , Fourkas John T. , Losert Wolfgang
Published: May 2021

Cells are able to integrate multiple, and potentially competing, cues to determine a migration direction. For instance, in wound healing, cells follow chemical signals or electric fields to reach the wound edge, regardless of any local guidance cues. To investigate this integration of guidance cues, we monitor the actin-polymerization dynamics of immune cells in response to cues on a subcellular scale (nanotopography) and on the cellular scale (electric fields, EFs). In the fast, amoeboid-type migration, commonly observed in immune cells, actin polymerization at the cell’s leading edge is the driver of motion. The excitable systems character of actin polymerization leads to self-propagating, two-dimensional wavefronts that enable persistent cell motion. We show that EFs guide these wavefronts, leading to turning of cells when the direction of the EF changes. When nanoridges promote one-dimensional (1D) waves of actin polymerization that move along the ridges (esotaxis), EF guidance along that direction is amplified. 1D actin waves cannot turn or change direction, so cells respond to a change in EF direction by generating new 1D actin waves. At the cellular scale, the emergent response is a turning of the cell. For nanoridges perpendicular to the direction of the EF, the 1D actin waves are guided by the nanotopography, but both the average location of new actin waves and the whole cell motion are guided by the EF. Thus, actin waves respond to each cue on its intrinsic length scale, allowing cells to exhibit versatile responses to the physical microenvironment.

Significance Statement

Effective cell migration requires the integration of multiple, and sometimes competing, guidance cues. For instance, in wound healing, immune cells are guided towards a wound edge by long-range electrical and chemical cues that may conflict with guidance cues from the local environment. How cells combine and respond to such cues is not well understood. We demonstrate that multiple guidance mechanisms can act simultaneously, but on different scales. Nanotopography, a local mechanical cue, guides individual waves of actin polymerization, thereby biasing the direction cell motion on the time scale of these waves. An external electric field applied at the same time biases the locations of new waves of actin polymerization, leading to overall directed migration over long distance scales.
Adenovirus transduction to express human ACE2 causes obesity-specific morbidity in mice, impeding studies on the effect of host nutritional status on SARS-CoV-2 pathogenesis
Authors: Rai Pallavi , Chuong Christina , LeRoith Tanya , Smyth James W , Panov Julia , Levi Moshe , Kehn-Hall Kylene , Duggal Nisha K. , Lucarelli James-Weger
Published: May 2021

The COVID-19 pandemic has paralyzed the global economy and resulted in millions of deaths globally. People with co-morbidities like obesity, diabetes and hypertension are at an increased risk for severe COVID-19 illness. This is of overwhelming concern because 42% of Americans are obese, 30% are pre-diabetic and 9.4% have clinical diabetes. Here, we investigated the effect of obesity on disease severity following SARS-CoV-2 infection using a well-established mouse model of diet-induced obesity. Diet-induced obese and lean control C57BL/6N mice, transduced for ACE2 expression using replication-defective adenovirus, were infected with SARS-CoV-2, and monitored for lung pathology, viral titers, and cytokine expression. No significant differences in tissue pathology, viral replication or cytokine expression were observed between lean and obese groups. Notably, significant weight loss was observed in obese mice treated with the adenovirus vector, independent of SARS-CoV-2 infection, suggesting an obesity-dependent morbidity induced by the vector. These data indicate that the adenovirus-transduced mouse model of SARS-CoV-2 infection is inadequate for performing nutrition studies, and caution should be used when interpreting resulting data.
aCPSF1 in synergy with terminator U-tract dictates archaeal transcription termination efficiency via the KH domains recognizing U-tract
Authors: Li Jie , Yue Lei , Zhang Wenting , Li Zhihua , Zhang Bing , Zhao Fangqing , Dong Xiuzhu
Published: May 2021

Recently, aCPSF1 was reported to function as the long-sought global transcription termination factor of archaea, while the working mechanism remains elusive. This work, through analyzing transcript-3′end-sequencing data of Methanococcus maripaludis, found positive correlations of both the terminator uridine(U)-tract and aCPSF1 with hierarchical transcription termination efficiencies (TTEs) at the genome-wide level. In vitro assays determined that aCPSF1 specifically binds to the terminator U-tract with U-tract number-related binding abilities, and in vivo assays demonstrated the two are indispensable in dictating high TTEs, revealing that aCPSF1 and the terminator U-tract in synergy determine high TTEs. The N-terminal KH domains equip aCPSF1 of specific binding to terminator U-tract and the in vivo aCPSF1-terminator U-tract synergism; aCPSF1’s nuclease activity was also required for TTEs. aCPSF1 also functioned as back-up termination for transcripts with weak intrinsic terminator signals. aCPSF1 orthologs from Lokiarchaeota and Thaumarchaeota exhibited similar U-tract synergy in dictating TTEs. Therefore, aCPSF1 and the intrinsic U-rich terminator could work in a noteworthy two-in-one termination mode in Archaea, which could be widely employed by archaeal phyla; using one factor recognizing U-rich terminator signal and cleaving transcript 3′-end, the archaeal aCPSF1-dependent transcription termination could display a simplified archetypal mode of the eukaryotic RNA polymerase II termination machinery.
Simple methods for quantifying super-resolved cortical actin
Authors: Garlick Evelyn , Faulkner Emma L. , Briddon Stephen J. , Thomas Steven G.
Published: May 2021

Cortical actin plays a key role in cell movement and division, but has also been implicated in the organisation of cell surface receptors such as G protein-coupled receptors. The actin mesh proximal to the inner membrane forms small fenced regions, or ‘corrals’, in which receptors can be constrained. Quantification of the actin mesh at the nanoscale has largely been attempted in single molecule datasets and electron micrographs. This work describes the development and validation of workflows for analysis of super resolved fixed cortical actin images obtained by both Super Resolved Radial Fluctuations (SRRF) and expansion microscopy (ExM). SRRF analysis was used to show a significant increase in corral area when treating cells with the actin disrupting agent cytochalasin D (increase of 0.31µm2 ± 0.04 SEM), and ExM analysis allowed for the quantitation of actin filament densities. Thus this work allows complex actin networks to be quantified from super-resolved images and is amenable to both fixed and live cell imaging.
Evolutionary systems biology reveals patterns of rice adaptation to drought-prone agro-ecosystems
Authors: Groen Simon C. , Joly-Lopez Zoé , Platts Adrian E. , Natividad Mignon , Fresquez Zoë , Mauck William M. , Quintana Marinell R. , Cabral Carlo Leo U. , Torres Rolando O. , Satija Rahul , Purugganan Michael D. , Henry Amelia
Published: May 2021

Rice was domesticated around 10,000 years ago and has developed into a staple for half of humanity. The crop evolved and is currently grown in stably wet and intermittently dry agro-ecosystems, but patterns of adaptation to differences in water availability remain poorly understood. While previous field studies have evaluated plant developmental adaptations to water deficit, adaptive variation in functional and hydraulic components, particularly in relation to gene expression, has received less attention. Here, we take an evolutionary systems biology approach to characterize adaptive drought resistance traits across roots and shoots. We find that rice harbors heritable variation in molecular, physiological, and morphological traits that is linked to higher fitness under drought. We identify modules of co-expressed genes that are associated with adaptive drought avoidance and tolerance mechanisms. These expression modules showed evidence of polygenic adaptation in rice subgroups harboring accessions that evolved in drought-prone agro-ecosystems. Fitness-linked expression patterns had predictive value and allowed us to identify the drought-adaptive nature of optimizing photosynthesis and interactions with arbuscular mycorrhizal fungi. Taken together, our study provides an unprecedented, integrative view of rice adaptation to water-limited field conditions.
Differences in nanoscale organization of DNase I hypersensitive and insensitive chromatin in single human cells
Authors: Brandstetter Katharina , Zülske Tilo , Ragoczy Tobias , Hörl David , Haugen Eric , Rynes Eric , Stamatoyannopoulos John A. , Leonhardt Heinrich , Wedemann Gero , Harz Hartmann
Published: May 2021

Methodological advances in conformation capture techniques have fundamentally changed our understanding of chromatin architecture. However, the nanoscale organization of chromatin and its cell-to-cell variance are less studied. By using a combination of high throughput super-resolution microscopy and coarse-grained modelling we investigated properties of active and inactive chromatin in interphase nuclei. Using DNase I hypersensitivity as a criterion, we have selected prototypic active and inactive regions from ENCODE data that are representative for K-562 and more than 150 other cell types. By using oligoFISH and automated STED microscopy we systematically measured physical distances of the endpoints of 5kb DNA segments in these regions. These measurements result in high-resolution distance distributions which are right-tailed and range from very compact to almost elongated configurations of more than 200 nm length for both the active and inactive regions. Coarse-grained modeling of the respective DNA segments suggests that in regions with high DNase I hypersensitivity cell-to-cell differences in nucleosome occupancy determine the histogram shape. Simulations of the inactive region cannot sufficiently describe the compaction measured by microscopy, although internucleosomal interactions were elevated and the linker histone H1 was included in the model. These findings hint at further organizational mechanisms while the microscopy-based distance distribution indicates high cell-to-cell differences also in inactive chromatin regions. The analysis of the distance distributions suggests that direct enhancer-promoter contacts, which most models of enhancer action assume, happen for proximal regulatory elements in a probabilistic manner due to chromatin flexibility.
Antibody structure prediction using interpretable deep learning
Authors: Ruffolo Jeffrey A. , Sulam Jeremias , Gray Jeffrey J.
Published: May 2021

Therapeutic antibodies make up a rapidly growing segment of the biologics market. However, rational design of antibodies is hindered by reliance on experimental methods for determining antibody structures. In recent years, deep learning methods have driven significant advances in general protein structure prediction. Here, we present DeepAb, a deep learning method for predicting accurate antibody FV structures from sequence. We evaluate DeepAb on two benchmark sets – one balanced for structural diversity and the other composed of clinical-stage therapeutic antibodies – and find that our method consistently outperforms the leading alternatives. Previous deep learning methods have operated as “black boxes” and offered few insights into their predictions. By introducing a directly interpretable attention mechanism, we show that our network attends to physically important residue pairs. For example, in prediction of one CDR H3 residue conformation, the network attends to proximal aromatics and a key hydrogen bonding interaction that constrain the loop conformation. Finally, we present a novel mutant scoring metric derived from network confidence and show that for a particular antibody, all eight of the top-ranked mutations improve binding affinity. These results suggest that this model will be useful for a broad range of antibody prediction and design tasks.

Significance

Accurate structure models are critical for understanding the properties of potential therapeutic antibodies. Conventional methods for protein structure determination require significant investments of time and resources and may fail. Although greatly improved, methods for general protein structure prediction still cannot consistently provide the accuracy necessary to understand or design antibodies. We present a deep learning method for antibody structure prediction and demonstrate improvement over alternatives on diverse, therapeutically relevant benchmarks. In addition to its improved accuracy, our method reveals interpretable outputs about specific amino acids and residue interactions that should facilitate design of novel therapeutic antibodies.
Use of waste foundry sand as fine aggregates for structural concrete – A review
Authors: M. Manjunatha , S.G.K. Rakshith
Published: May 2021

Purpose

Waste foundry sand (WFS) is a by-product of the metal casting industries and is used for land filling purposes. Disposing of waste creates problems to environment and increases disposal values. To reduce environmental pollutions and solving disposal problems, several authors in worldwide are carried out research work by partial and complete replacing of natural sand with WFS in concrete mixtures. It is found that WFS can be used for production of structural grade concrete. The mechanical characteristics and flexural properties of RC beams has been reviewed in this paper. From this literature review, it has been noticed that there are improvements in concrete strength properties with WFS.

Design/methodology/approach

The results of various properties of concrete have been discussed in this review articles such as compressive strength, split tensile strength, flexural strength, modulus of elasticity, SEM micro-structures and flexural strength properties of RC beams.

Findings

From the literature review, it is found that there is gap of research on flexural behavior of reinforced concrete beam with WFS.

Originality/value

By using WFS effectively, the environmental pollutions and dumping of waste can be reduced. WFS can be successfully used in structural concrete members.
The impact of corporate bankruptcy on strategic management: using a textual analysis approach to analyze executives’ opinions
Authors: Nagel Raphael , Aviles Carmen
Published: May 2021

Purpose

In the past decade, the development of the global economy, the change in organizational structures and the maturing of new technologies have led to considerable changes in business structures. Emergency situations, such as the recent COVID-19 pandemic, have led many companies to declare bankruptcy. In this context, the present study aims to analyze strategic opinions of company executives in a declaration of bankruptcy.

Design/methodology/approach

To this end, an innovative approach is applied to strategic management and business. First, the authors conducted 14 interviews with executives, and the interview data were transcribed. Second, using textual analysis and data mining techniques, the transcripts were analyzed to understand the importance of indicators identified as relevant in companies in a declaration of bankruptcy.

Findings

This resulted in identification of 10 relevant indicators perceived by executives to avoid or anticipate a state of bankruptcy, including innovation, business adaptability, room for improvement in production processes, time to react to situations of alarm, layoffs, support from public institutions, suppliers, international and national regulations, impact on the industry, credits and debts.

Originality/value

The paper concludes with a discussion of important theoretical and practical implications of these findings for the industry. Also, strategic management decision-making strategies are presented as a result of the innovative textual analysis approach used.
Non-sponsored brand-related user-generated content: effects and mechanisms of consumer engagement
Authors: Davcik Nebojsa S. , Langaro Daniela , Jevons Colin , Nascimento Rita
Published: May 2021

Purpose

This study aims to investigate whether users’ engagement with a social media platform is affected as they engage in non-sponsored brand-related user-generated content (UGC). The concept of non-sponsored brand-related UGC encapsulates various social media patterns in which individuals choose how to consume, contribute or create brand-related content with no formal brand incentive or control.

Design/methodology/approach

The study focuses on the question of how users engage with non-sponsored brand-related UGC on Instagram and assesses the influence of UGC perceived value, using partial least squares variance-based structural equation modeling.

Findings

The research shows significant and positive effects of UGC on Instagram users’ intentions to engage with the platform and the influence of UGC perceived value on UGC uses. The findings deepen the understanding of the mechanisms underlying non-sponsored brand-related UGC in consumer engagement marketing, with significant implications for brand managers and the future development of Instagram and other social media platforms.

Originality/value

The UGC functional, social and emotional values are evaluated for their effects on generating the three distinct patterns of consumer online brand-related activities (consumer, contribute and create) in the non-sponsored brand-related UGC context.
Customer relationship and the operating performance following private placements
Authors: Teng Fei , Xia Xue , Xin Yu
Published: May 2021

Purpose

Close relationship with major customers, by curtailing opportunistic behaviors during private placements (PPs) and guaranteeing the production and sales of products after, is expected to facilitate the realization of PP’s strategic goals. However, major customers, on the contrary, may impair PP’s performance because of their strong bargaining power. Based on the transaction cost theory and relational contract theory, this paper aims to investigate the impact of major customers on firms’ strategic development in the context of private placements. The mechanisms of such impact are analyzed from the prospect of economies of scale, supervision and the rip-off effect by major customers. Further, the moderating role of the customer relationship investment (CRI) is considered.

Design/methodology/approach

Using a sample of China’s non-financial A-share listed firms during 2010-2016, this paper empirically investigates the impact of customer relationships on firms’ operating performance following PPs. In the main regressions, the sales growth rate serves as the dependent variable to measure PP’s operating performance, while the customer concentration proxies for the closeness of customer relationship. This study captures the impact of customer relationships on PPs’ performance by looking at the coefficient of the interaction term of post PP dummy and customer concentration. In the additional tests, selling and management expenses along with entertainment and traveling expenditures are used to measure customer relationship investment.

Findings

Results show that major customers help improve PPs’ strategic performance. The more concentrated the customer portfolio is, the higher operating performance will be after the PPs. Such a relationship is stronger when CRI is at a higher level. However, CRI also incurs costs, which impairs the effect of major customers on net profit. Further research finds that the effect of major customers is more pronounced in situations of extensional PPs, with actively interactive customers and in non-state-owned firms. In addition, state-owned customers with strong bargaining power have impaired the role of customers in promoting PP’s operating performance.

Originality/value

This paper validates the role of customers in firms’ strategic development. The study not only contributes to the research on the economic consequences of customers but also adds to the evolving literature of factors affecting the performance of PPs. The findings of the study have important practical implications for both customer relationship management and the supervision of PPs.
Board Gender Diversity Codes, Quotas and Threats of Supranational Legislation: Impact on Director Characteristics and Corporate Outcomes
Authors: Martínez‐García Irma , Terjesen Siri , Gómez‐Ansón Silvia
Published: May 2021

We explore how a code, soft quota and a proposal for supranational law for board gender diversity affects women directors’ human capital characteristics and corporate outcomes with an unbalanced panel of 116 non‐financial firms and 1,321 firm‐year observations from 2003 to 2016 in Spain. Consistent with resource dependence theory, after a non‐punitive law is passed, boards seek to appoint more female directors who possess human capital attributes that will reduce uncertainty and bring necessary resources to firms. Compared with their pre‐law counterparts, the new female directors tend to have more human capital in terms of executive experience in non‐listed firms, and some non‐executive backgrounds, education and international experience; however, these new women directors generally possess less human capital than their male counterparts. Upper echelons theory suggests that board directors can meaningfully impact corporate outcomes. Overall, our results contradict upper echelons predictions about the impact of a regulation‐driven increase of women directors on corporate outcomes. Indeed, we find a lack of impact of the increase in women's presence on boards on corporate outcomes. Regarding policy, our findings substantially differ from those reported for countries with ‘hard law’ board gender quotas.
Impacts of Sea‐Level Rise on Hypoxia and Phytoplankton Production in Chesapeake Bay: Model Prediction and Assessment
Authors: Cai Xun , Shen Jian , Zhang Yinglong J. , Qin Qubin , Wang Zhengui , Wang Harry
Published: May 2021

In this study, the influence of sea‐level rise (SLR) on seasonal hypoxia and phytoplankton production in Chesapeake Bay is investigated using a 3D unstructured grid model. Three SLR scenarios (0.17, 0.5, and 1.0 m) were conducted from 1991 to 1995. Results show that the summer hypoxic volume (HV) increases about 2%, 8%, and 16%, respectively, for these three scenarios, compared with Base Scenario. The contributions of physical and biological processes on the increase in the HV were analyzed. With the projected SLR, enhanced gravitational circulation transports more oxygen‐rich water in the bottom layer from the mouth. However, the pycnocline moves upwards along with increasing water depth, which largely prolongs the time for dissolved oxygen (DO) to be transported to the bottom. The altered physical processes contribute greatly to a larger HV bay‐wide. Besides, SLR increases the whole Bay phytoplankton production, with a larger increase in shallow areas (e.g., 53% in areas with depth <1 m under SLR of 0.5 m). Enhanced light availability is suggested to be the major driver of blooming phytoplankton under SLR in shallow areas. While increased DO production over the euphotic zone is mostly released to the atmosphere and transported downstream, the increase in settled organic matter greatly promotes DO consumption in the water column. The increased respiration is another major cause of the HV increase besides the physical contributions.
An Interval Two‐Stage Classified‐Allocation Model for Regional Water Management under Nonstationary Condition
Authors: Chen Shu , Li Qingqing , Xu Jijun , Wang Dong , Wang Yongqiang , Yuan Zhe
Published: May 2021

Due to climate change and human activities, the assumption of the stationarity of hydrologic features will no longer hold. Moreover, uncertainties, such as the apparent randomness of hydrologic elements, and complexities, such as the existence of various water users with different characteristics, also introduce huge challenges for water managers. To address nonstationarity, uncertainty, and complexity, a new approach is proposed for the optimal allocation of regional water resources. This objective was achieved via two steps: First, the generalized additive model was chosen to analyze the nonstationary probability distribution of the hydrologic dataset; then, an interval two‐stage classified‐allocation model is formulated by incorporating two‐stage stochastic programming, interval parameter programming and classification thought. The model can not only address uncertainties, which were expressed as interval parameters and probability distributions, but can also handle complexities by classifying the water users into agricultural and nonagricultural users. The approach was applied to the Zhanghe Irrigation District to optimize available water allocation for municipality, industry, hydropower, and agriculture in two planning years (namely 2010 and 2015). The annual inflow of the Zhanghe Reservoir is found to be nonstationary and can be well fitted by Gamma distribution with one location parameter based on a nonlinear function of time. Moreover, the difference in output between the two years with different inflow probability distributions indicates the need for nonstationary analysis. Comparison to the inexact two‐stage water management model that did not consider the variation of agricultural water requirement shows the meaning of classification. From the results, municipality and industry are more competitive than agriculture and then hydropower. For agriculture, winter rape and cotton have higher priority than rice. These solutions of the optimal targets and optimal water allocation for different water users can help managers to accurately develop allocation plans under uncertain and nonstationary conditions.
Becoming an operating system
Authors: RUTHERFORD DANILYN
Published: May 2021

A remarkable experiment in assistive technology, known as PODD, draws on and challenges mainstream understandings of communication in the US. To engage disabled people in conversation, caregivers turn to PODD books, which are binders of laminated sheets that display icons. As caregivers use these books, they act as “operating systems,” listing directions as they navigate from page to page, then animating the selected utterance in an enthusiastic tone. PODD plays on the language ideology that underlies most communication systems, which are designed to liberate speaking subjects trapped by the limitations of their bodies and minds. But PODD also confronts its users with aspects of communication that set aside the question of meaning. Drawing on interviews and participant observation in trainings with my nonverbal daughter, I show how caregivers struggle to inhabit a community of sign use in which referential meaning is both longed for and beside the point. [disability, communication, language ideology, personhood, ethics, affect, United States]
A self‐help version of the New Forest Parenting Programme for parents of children with attention deficit hyperactivity disorder: a qualitative study of parent views and acceptability
Authors: Tarver Joanne , Daley David , Sayal Kapil
Published: May 2021

Background

Although parent interventions are recommended as a frontline treatment approach for children with attention deficit hyperactivity disorder (ADHD), a number of practical and situational barriers can impact accessibility and availability. Self‐help parent interventions offer a potential alternative to therapist‐led interventions when barriers prevent access to face‐to‐face treatment. This qualitative study aims to explore participant views and acceptability of self‐help parent interventions.

Method

Semi‐structured interviews were conducted with parents/carers of 12 children (age 6–10 years) with ADHD who received the self‐help version of the New Forest Parenting Programme (NFPP‐SH) as part of a randomised controlled trial. Thematic analysis (as proposed by Braun and Clarke) was used to analyse the data.

Results

Overall, participants had favourable views of the self‐help intervention but also experienced some barriers to treatment adherence. Six key themes were identified in parent interviews related to parental desire to learn more; acquisition of new skills; the flexibility of the intervention; self‐help intervention vs. traditional therapist‐led formats; barriers to engagement in the home environment; and need for earlier access to help.

Conclusions

NFPP‐SH was an acceptable intervention for parents. However, some parents may need additional support to overcome barriers associated with completing an intervention at home. Implications for healthcare providers and researchers developing self‐help parent interventions for ADHD and child behaviour are discussed.
Profiles of Minority‐Majority Language Proficiency in 5‐Year‐Olds
Authors: Hoff Erika , Tulloch Michelle K. , Core Cynthia
Published: May 2021

Children from language minority homes reach school age with variable dual language skills. Cluster analysis identified four bilingual profiles among 126 U.S.‐born, 5‐year‐old Spanish–English bilinguals. The profiles differed on two dimensions: language balance and total language knowledge. Balance varied primarily as a function of indicators of the relative quantity and the quality of their language exposure (amount of home exposure and maternal education in each language). Total language knowledge varied primarily as a function of indicators of children’s language learning ability (phonological memory and nonverbal intelligence). English dominance was more prevalent than balanced bilingualism; there was no Spanish dominant profile, despite average Spanish dominance in home language use. There was no evidence of a tradeoff between English and Spanish skills.