bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of hypermetabolic mediastinal-hilar lymph nodes determined by PET/CT with EBUS-TBNA and calculation of SUVmax cutoff values in differentiation of malignancy
Authors: Ugurlu Erhan , Metin Melis , Cetin Nazli , Kilicarslan Emel , Degirmencioglu Serkan , Sengoz Tarik , Akbudak Ilknur Hatice , Gokoz Dogu Gamze , Aydogmus Umit
Published: September 2023

Computed tomography (CT) and positron emission tomography (PET) are the most commonly used methods for diagnosis and staging in both malignant and benign diseases of the lung parenchyma and mediastinum. Endobronchial ultrasonography (EBUS) guided transbronchial needle aspiration biopsy (TBNA) has become widespread in recent years because it allows minimally invasive tissue sampling. PET-CT has high sensitivity in the diagnosis of malignancy but has low specificity. The false positive rate is high with the SUVmax 2.5 cutoff value, which is widely used in studies about malignancy. In our study, we evaluated lymph nodes with high F18-fluorodeoxyglucose (FDG) uptake on PET/CT and sampled by EBUS-TBNA. We aimed to calculate the new SUVmax cutoff values in the differentiation of malignancy. Our study included 103 patients who were examined for any reason and who underwent biopsy with EBUS-TBNA due to mediastinal or hilar lymph node enlargement on PET-CT. The relationship between PET-CT findings and EBUS findings, EBUS-TBNA results was evaluated. Biopsies were taken from 140 lymph nodes in 103 patients included in our study, and 39 (27.8%) were diagnosed as malignant. In our study, when the SUVmax cutoff value in PET-CT is taken as 2.54, the sensitivity is 98%, but the specificity remains at the level of 12%. When the SUVmax cutoff value in PET-CT was taken as 4.58, the sensitivity was 92% and the specificity was 49%. When this value was accepted as 5.25, and 6.09 the sensitivity was respectively 90% and 85%, the specificity was respectively 52% and 60%. In evaluations, we conducted in order to determine different SUVmax cutoff values that can be used for higher sensitivity and specificity in malignancy studies, the cutoff values were 4.58, 5.25, and 6.09. It is thought that these cutoff values will be useful both for diagnosing malignancy and for distinguishing benign pathologies.
The combined orthodontic and restorative treatment for patients with malocclusion and dentition defects: A randomized controlled trial
Authors: Shen Yan , Jiang Xiongying , Yu Jing
Published: September 2023

Background:

To explore the effects of a combined orthodontic and restorative approach on chewing, swallowing, and language function in patients with malocclusion and dental defects.

Methods:

A total of 112 patients with malocclusion and dentition defects admitted to the Lianyungang Hospital of Traditional Chinese Medicine from June 2019 to June 2022 were prospectively selected. The patients were divided into study and control groups using a simple random number table method, with 56 patients in each group. The control group received routine restoration, whereas the study group received a combination of orthodontic and restorative treatments. The chewing function, swallowing and language function, and gingival periodontal condition before and after treatment in both groups were compared using t-test or Wilcoxon test, while treatment satisfaction were compared using chi-square test or Fisher exact test.

Results:

After treatment, maximum area frame bite force/max movie force in both groups increased compared to before treatment, while occlusion time, bite force distrbution balance, and standard deviation hue decreased compared to before treatment. Moreover, maximum area frame bite force/max movie force in the study group was higher than that in the control group, whereas occlusion time, bite force distrbution balance, and standard deviation hue were lower than those in the control group (P < .05). The swallowing and language function scores of the study group were higher than those of the control group (P < .05). After treatment, the bleeding index, plaque index, and probing depth of both groups decreased compared to before treatment, and the study group was lower than the control group (P < .05). The treatment satisfaction of the study group (94.64%) was higher than that of the control group (82.14%) (P < .05).

Conclusion:

Adopting a combined orthodontic and restorative approach to intervene in patients with malocclusion and dentition defects is beneficial for improving their periodontal condition, effectively restoring chewing, swallowing, and language functions, and achieving high patient satisfaction.
Gonococcal endocarditis in a 32-year-old male: a rare presentation of an underrecognized disease – case report
Authors: Abu-Hilal Lila H. , Njoum Yumna , Jabbarin Farah M. , Barghouthi Duha I. , Hamamdah Abdullah , Bourini Mohammad , Mtour Sameer
Published: September 2023

Introduction and importance:

Disseminated gonococcal infection (DGI) is an infrequent but serious complication of gonorrhea that can exhibit atypical symptoms. While rare, it can lead to infective endocarditis (IE), a condition that affects the heart valves and can result in severe and potentially life-threatening outcomes.

Case presentation:

We present a case of Neisseria gonorrhoeae-caused IE confirmed by blood culture and direct isolation from the aortic valve vegetation. Our patient experienced complications, including glomerulonephritis, respiratory failure, and positive troponin. Urgent surgery successfully removed a large vegetation, replaced the aortic valve, and improved cardiac function. Follow-up showed symptom resolution.

Clinical discussion:

DGI can present atypically with a triad of tenosynovitis, polyarthralgia, and rash, even without genitourinary symptoms. However, it can also present with nonspecific symptoms, leading to a later diagnosis of IE, as observed in our patient, who developed an aortic valve abscess and aortic regurgitation.

Conclusion:

This case provides important insights into the diagnosis and management of gonococcal endocarditis, emphasizing the significance of early recognition, timely intervention, and multidisciplinary collaboration in improving patient outcomes. It is imperative to have a high level of suspicion for this rare entity, given its high virulence and potential for severe complications.
A massive primary hydatid splenic cyst was successfully managed through open total splenectomy: a case report and review article
Authors: Mansour Marah , Nassar Kinan , Masri Mahmod , Kanas Mahmoud , Aldrea Fatima , Alzaylaa Yara , Salloum Hayan , Ahmad Youssef , Samha Raghad , Kanjawi Omar
Published: September 2023

Background:

Cystic echinococcosis (CE) is a parasitic infection that is caused by the tapeworm Echinococcus granulosus. CE is very common, especially in the rural areas of developing countries. The most commonly affected organs by hydatid cysts are the liver and the lungs. However, the primary splenic hydatid cyst (PSHC) is a very rare manifestation of CE with an incidence of 0.5–8%.

Case presentation:

A 17-year-old female patient presented with abdominal pain which gradually increased over months, along with anorexia and vomiting. Computerized tomography showed a massive splenic cystic mass. An open total splenectomy was performed. By follow-up, the platelet count and a postoperative chest X-ray were normal. The patient was prescribed Albendazole and analgesics. The pathological study confirmed the diagnosis of PSHC.

Conclusion:

Despite the occurrence of PSHC being very rare, it is very important to take it into consideration, especially in endemic areas.
Median nerve schwannoma with a diagnostic delay of 8 years: a case report
Authors: Neupane Durga , Dahal Alok , Lageju Nimesh , Jaiswal Lokesh S. , Mahat Asim , Kafle Sujan , Poudel Prabhat , Pandit Narendra , Singh Surjan K. , Ghimire Sagun , Dhonju Kiran
Published: September 2023

Introduction:

Schwannomas are benign tumors of the peripheral nerve sheath, and the median nerve is the most commonly involved nerve. These benign tumors of the peripheral nerve sheath are very rare; they are clinically and radiologically similar to most other benign swellings of the hand; thus, they are often misdiagnosed.

Case Presentation:

A 41-year-old lady presented with an 8-year-long history of swelling over the distal forearm. The tumor measured 3.5×3.5×3.5 mm and was located over the flexor aspect of the distal part of her right forearm. Schwannoma was suspected from the clinical presentation and imaging, but the final diagnosis was established only after the surgery and histopathological analysis. At the follow-up after 1 year, the patient is doing well and her symptoms have not recurred.

Conclusion:

Imaging characteristics of schwannoma can be misinterpreted as some other condition, making the preoperative diagnosis very difficult and important. Thus, clinicians should be aware of such swellings, especially those that have been unnoticed or misdiagnosed, and provide optimal diagnoses to confer good outcomes.
Rise of Marburg virus in Africa: a call for global preparedness
Authors: Okesanya Olalekan J. , Manirambona Emery , Olaleke Noah O. , Osumanu Hisham A. , Faniyi Ayodeji A. , Bouaddi Oumnia , Gbolahan Olatunji , Lasala Jose J. , Lucero-Prisno Don E.
Published: September 2023

The Marburg virus disease (MVD) is caused by a rare RNA virus that can result in severe hemorrhagic fever in humans and other primates. The disease was first discovered in 1967 in Marburg Frankfurt in Germany and since then, sporadic cases have been reported in southeastern Africa. The Egyptian fruit bat is considered a reservoir for the virus, which can be transmitted through direct contact with infected bat or monkey tissue, bodily fluids, or contaminated objects. The Marburg virus disease shares clinical features with the Ebola virus disease, and there are no widely accepted vaccines or antiviral medications to treat it. The article provides an overview of Marburg virus (MARV) outbreaks in Africa, including the most recent outbreaks in Guinea, Ghana, Equatorial Guinea, and Tanzania. The authors discuss the recent outbreaks and the implications of the spread of MARV to Africa’s healthcare systems. The authors also present key recommendations for both multicountry and global preparedness efforts in order to better prevent and respond to future MARV outbreaks and other viruses with an epidemic potential.
Dynamic Susceptibility Contrast-Enhanced Perfusion-Weighted Imaging in Differentiation Between Recurrence and Pseudoprogression in High-Grade Glioma: A Meta-analysis
Authors: Gu Xindong , He Xining , Wang Hualong , Li Jianhua , Chen Ruwei , Liu Hongen
Published: September 2023

Introduction

In glioma patients that have undergone surgical tumor resection, the ability to reliably distinguish between pseudoprogression (PsP) and a recurrent tumor (RT) is of key clinical importance. Accordingly, this meta-analysis evaluated the utility of dynamic susceptibility contrast-enhanced perfusion-weighted imaging as a means of distinguishing between PsP and RT when analyzing patients with high-grade glioma.

Materials and Methods

The PubMed, Web of Science, and Wanfang databases were searched for relevant studies. Pooled analyses of sensitivity, specificity, positive likelihood ratio (PLR), and negative likelihood ratio (NLR) values were conducted, after which the area under the curve (AUC) for summary receiver operating characteristic curves was computed.

Results

This meta-analysis ultimately included 21 studies enrolling 879 patients with 888 lesions. Cerebral blood volume–associated diagnostic results were reported in 20 of the analyzed studies, and the respective pooled sensitivity, specificity, PLR, and NLR values were 86% (95% confidence interval [CI], 0.81–0.89), 83% (95% CI, 0.77–0.87), 4.94 (95% CI, 3.61–6.75), and 0.18 (95% CI, 0.13–0.23) for these 20 studies. The corresponding AUC value was 0.91 (95% CI, 0.88–0.93), and the publication bias risk was low (P = 0.976). Cerebral blood flow–related diagnostic results were additionally reported in 6 of the analyzed studies, with respective pooled sensitivity, specificity, PLR, and NLR values of 85% (95% CI, 0.78–0.90), 85% (95% CI, 0.76–0.91), 5.54 (95% CI, 3.40–9.01), and 0.18 (95% CI, 0.12–0.26). The corresponding AUC value was 0.92 (95% CI, 0.89–0.94), and the publication bias risk was low (P = 0.373).

Conclusions

The present meta-analysis results suggest that dynamic susceptibility contrast-enhanced perfusion-weighted imaging represents an effective diagnostic approach to distinguishing between PsP and RT in high-grade glioma patients.
Effects of Specific Protective Resources on the Burnout Levels of Selected Visayan Medical Students from Online-Based Education during COVID-19 Pandemic: A Cross-Sectional Study
Authors: Arpilleda Jordan Joy , Bunal Julia Patricia , Rose Montano Margaret Therese , Torrenueva Lesly Marie , Acebes Ma. Jobelle , Homecillo Margaret Angeli , Salvador Juan Paolo , Tan Frances Gabrielle , Villanueva Zackaree Michael
Published: September 2023

Background

Burnout is a phenomenon characterized as a consistent state of being exhausted physically, mentally, and emotionally. Grit, tolerance for ambiguity, religiosity, and social support are protective factors that may mitigate burnout and improve life satisfaction. This study assessed the association between specific protective resources of students from a medical school in Visayas at all year levels with online-based education-related burnout during the COVID-19 pandemic.

Methods

A total of 234 medical students from a medical school in Visayas during the academic year 2020-2021 were sampled using stratified random sampling technique. Demographics were obtained. Specific protective resources of grit, religiosity, social support and tolerance for ambiguity, and burnout symptoms were measured using validated online questionnaires. Protective associations of specific resources on burnout levels were assessed using multivariate logistic regression analysis. Predictive capabilities of resources with statistically significant protective effects were summarized using Receiving Operating Characteristic (ROC) curve.

Results

All year levels experienced burnout based on Maslach Burnout Inventory-Student Survey (MBI-SS) subscales, with PBL 2 having the highest incidence comprising 33 respondents (49%). Majority of the students experienced moderate burnout on emotional exhaustion (44%) and low burnout on depersonalization (58%), while all of them had high burnout levels on the subscale of personal accomplishment (100%). Most students were moderately gritty (91%) and had high tolerance for ambiguity (98%), overall religiosity index (82%), and social support from significant others (68%); family (68%); and friends (76%). Grit, religiosity and social support had positive significant correlations and reductive effects to burnout. Tolerance for ambiguity did not show any significant relationship with burnout. Grit, religiosity and social support are good predictors of burnout. Grit had good diagnostic accuracy and discrimination. Religiosity and social support were moderately accurate predictors of burnout.

Conclusions

Grit, religiosity and social support are significantly protective on burnout levels of medical students from online-based education during the COVID-19 pandemic.
Pilot Clinical Validation of a Machine Learning Platform for Noninvasive Smartphone-Based Assessment of Corneal Epithelial Integrity
Authors: Zhang Andrew Y. , Pratap Jayanth S. , Young James R. , Lui Joshua , Attari Kian , Srivastava Arnav A. , Wu Erica R. , Moreno Aracely D. , Miall Annie , Iyer Jay M. , Mantena Sreekar , Chandra Jay , Joshi Vineet P. , Jacobs Deborah S.
Published: September 2023

Purpose

Fluorescein staining (FS) is a standard method of assessing corneal epithelium (CE) integrity. However, the equipment and personnel required for FS may be unavailable in low-resource environments. We developed and validated a low-cost, noninvasive, and quantitative CE evaluation pipeline using a custom smartphone attachment and convolutional neural networks (CNNs).

Methods

A 3D-printed smartphone attachment and placido disk illumination module was attached to a OnePlus 7 Pro smartphone. 26 smartphone-acquired images were obtained from 15 subjects, comprising a dataset including healthy eyes and corneal epitheliopathies of Oxford grade I-V. A classifier CNN was trained on 8 subjects (23,173 image patches) to identify areas of suspected epithelial disruption, and validated on 7 subjects (10,883 image patches). The fraction of disrupted corneal surface area (FDSA) was computed for each subject from the model output. Results were compared with FS slit lamp photos which were independently graded by two clinicians using the Oxford scheme.

Results

FDSA showed promise as a non-invasive marker of CE integrity, with mean FDSA in the Oxford >II cohort being higher than the Oxford ≤II cohort (p = 0.04andp = 0.09using Oxford scores from each clinician, respectively). Additionally, areas of CE disruption identified by our smartphone-based technique showed qualitative concordance with those revealed by FS.

Conclusions

Our technique for smartphone-based CE imaging and automated analysis is a promising low-cost, noninvasive method to quantitatively evaluate the CE.

Translational Relevance

This tool can be used to evaluate ocular surface disease in low-resource regions.
Perspectives of Researchers and Clinicians on Patient and Public Involvement (PPI) in Preclinical Spinal Cord Research: An Interview Study
Authors: Carroll Pádraig , Dervan Adrian , McCarthy Ciarán , Beirne Cliff , Harte Geoff , O’Flynn Dónal , Quinlan John , Smith Éimear , Moriarty Frank , O’Brien Fergal J. , Flood Michelle
Published: September 2023

Study Design

Qualitative study

Objective

To explore the perspectives of preclinical spinal cord researchers and clinicians involved in the treatment of spinal cord injury on patient and public involvement (PPI) in preclinical research.

Setting

Preclinical spinal cord injury research.

Methods

Semi-structured interviews were conducted online to collect data that was analysed thematically.

Findings

Twenty-two participants (11 clinicians and 11 preclinical researchers) were interviewed. Participants recognised the value of PPI in improving the relevance of preclinical spinal cord research and providing a source of motivation for lab-based research. The perceived distance between preclinical research and the day-to-day experiences of PPI contributors was identified as a major barrier. Inclusive practices and the highly networked and motivated community of people affected by spinal cord injury were noted as facilitators. Building strong partnerships was considered essential for successful PPI.

Conclusions

While PPI has traditionally been more commonly associated with clinical research, participants identified the potential benefits of PPI in preclinical spinal cord research to provide context and improve research relevance and impact. Preclinical researchers should explore how PPI can be incorporated in their work.
Effectiveness of ReCOVery APP to improve the quality of life of Long COVID patients: a 6-month follow-up randomized clinical trial
Authors: Samper-Pardo Mario , Oliván-Blázquez Bárbara , León-Herrera Sandra , Sánchez-Arizcuren Rafael , Casado-Vicente Verónica , Sánchez-Recio Raquel
Published: September 2023

The main objective of this study is to analyse the clinical efficacy of medium-term telerehabilitation in the recovery of patients with Long COVID using ReCOVery APP, administered in the Primary Health Care (PHC) setting. The second objective is to identify significant patterns associated with an improvement in their quality of life predicted by other study variables. To this end, a randomised clinical trial was conducted with two parallel groups of a total of 100 patients with Long COVID. The control group continued with their usual treatment (TAU), established by their primary care physician. The intervention group, in addition to continuing with their TAU, attended three sessions based on motivational methodology and used ReCOVery APP for six months. The main variable was quality of life. The results of this study concluded that ReCOVery APP was not significantly more effective in improving the quality of life of patients with Long COVID. There was low adherence of participants. However, linear regression analyses revealed significant patterns of improvement in overall quality of life and mental health predicted by time of use of the APP and the personal construct of self-efficacy. In addition, all participants significantly improved their physical and mental health over the duration of the intervention. In conclusion, meaningful use of the ReCOVery APP may contribute to improving the quality of life of patients with Long COVID, but strategies to improve adherence need to be encouraged.

Trial Registration No

ISRCTN91104012.
Human hippocampal ripples tune cortical responses in uncertain visual contexts
Authors: Frank Darya , Moratti Stephan , Sarnthein Johannes , Li Ningfei , Horn Andreas , Imbach Lukas , Stieglitz Lennart , Gil-Nagel Antonio , Toledano Rafael , Friston Karl J. , Strange Bryan A.
Published: September 2023

To be able to encode information efficiently, our perceptual system should detect when situations are unpredictable (i.e., informative), and modulate brain dynamics to prepare for encoding. Here we show, with direct recordings from the human hippocampus and visual cortex, that after exposure to unpredictable visual stimulus streams, hippocampal ripple activity increases in frequency and duration prior to stimulus presentation, indicating context and experience-dependent prediction of predictability. Pre-stimulus hippocampal ripples suppress changes in visual (occipital) cortex gamma activity associated with uncertainty, and modulate post-stimulus prediction error gamma responses in higher-level visual (fusiform) cortex to surprising (i.e., unpredicted) stimuli. These results link hippocampal ripples with predictive coding accounts of neuronal message passing—and precision-weighted prediction errors—revealing a mechanism relevant for perceptual synthesis and subsequent memory encoding.
Circulating PACAP levels are associated with altered imaging measures of entorhinal cortex neurite density in posttraumatic stress disorder
Authors: Granger Steven J , May Victor , Hammack Sayamwong E , Akman Eylül , Jobson Sydney A. , Olson Elizabeth A , Pernia Cameron D , Daskalakis Nikos P , Ravichandran Caitlin , Carlezon William A , Ressler Kerry J , Rauch Scott L , Rosso Isabelle M
Published: September 2023

Background

Pituitary adenylate cyclase-activating polypeptide (PACAP) regulates plasticity in brain systems underlying arousal and memory and is associated with posttraumatic stress disorder (PTSD). Research in animal models suggests that PACAP modulates entorhinal cortex (EC) input to the hippocampus, contributing to impaired contextual fear conditioning. In PTSD, PACAP is associated with higher activity of the amygdala to threat stimuli and lower functional connectivity of the amygdala and hippocampus. However, PACAP-affiliated structural alterations of these regions have not been reported. Here, we examined whether peripheral PACAP levels were associated with neuronal morphology of the amygdala and hippocampus (primary analysis), and EC (secondary analysis) using Neurite Orientation Dispersion and Density Imaging.

Methods

Sixty-four (44 female) adults (19 to 54 years old) with DSM-5 Criterion A trauma exposure completed the Clinician-Administered PTSD Scale (CAPS-5), a blood draw, and magnetic resonance imaging. PACAP38 radioimmunoassay was performed and T1-weighted and multi-shell diffusion- weighted images were acquired. Neurite Density Index (NDI) and Orientation Dispersion Index (ODI) were quantified in the amygdala, hippocampus, and EC. CAPS-5 total score and anxious arousal score were used to test for clinical associations with brain structure.

Results

Higher PACAP levels in blood were associated with greater EC NDI (β=0.31, q=0.034) and lower EC ODI (β=-0.30, q=0.042) and not hippocampal or amygdala measures. Neither EC NDI nor ODI was associated with clinical measures.

Conclusions

Circulating PACAP levels were associated with altered neuronal density of the EC but not hippocampus or amygdala. These findings strengthen evidence that PACAP may impact arousal- associated memory circuits.
Characteristics of the sexual networks of gay, bisexual, and other men who have sex with men in Montréal, Toronto, and Vancouver: implications for the transmission and control of mpox in Canada
Authors: Xiu Fanyu , Anato Jorge Luis Flores , Cox Joseph , Grace Daniel , Hart Trevor A. , Skakoon-Sparling Shayna , Dvorakova Milada , Knight Jesse , Wang Linwei , Gatalo Oliver , Campbell Evan , Zhang Terri , Sbihi Hind , Irvine Michael A. , Mishra Sharmistha , Maheu-Giroux Mathieu
Published: September 2023

Background

The 2022-2023 global mpox outbreak disproportionately affected gay, bisexual, and other men who have sex with men (GBM). In Canada, >70% of cases thus far have been among GBM in Montréal, Toronto, and Vancouver. We examined how the distributions of sexual partners 1) varied by city and over time related to the COVID-19 pandemic and 2) were associated with mpox transmission.

Methods

TheEngage Cohort Study(2017-2023) recruited GBM via respondent-driven sampling in Montréal, Toronto, and Vancouver (n=2,449). We compared numbers of sexual partners in the past 6 months across cities and three time periods: pre-COVID-19 pandemic (2017-2019), pandemic (2020-2021), and post-restrictions (2021-2023). We modeled the distribution of sexual partner numbers using Bayesian negative binomial regressions and post-stratification, adjusting for sampling design and attrition. We estimated the basic reproduction number (R0), secondary attack rate (SAR), and cumulative incidence proportion of mpox using the fitted distributions and case timeseries.

Results

The pre-COVID-19 pandemic distribution of sexual partner numbers was similar across cities: participants’ mean number of partners was 10.3 (95%CrI: 9.3-11.3) in Montréal, 12.8 (11.1-14.7) in Toronto, and 10.6 (9.41-11.9) in Vancouver. Partner numbers decreased during the pandemic in all cities. Post-restrictions, sexual activity increased but remained well below pre-pandemic levels. Based on reported cases and post-restrictions distributions, the estimatedR0(2.4-2.6) and cumulative incidences (0.6-0.9%) were similar across cities. The estimated average SAR across cities was 79%.

Conclusion

GBM sexual activity after restrictions were lifted remained below pre-pandemic levels. Comparable sexual partner distributions across cities may explain similarities in mpoxR0and cumulative incidence across cities. Public health authorities should consider the risk of mpox resurgence for future vaccination and surveillance strategies as sexual activity is expected to recover.
Development of a rapid and highly accurate method for13C tracer-based metabolomics and its application on a hydrogenotrophic methanogen
Authors: Fukuyama Yuto , Shimamura Shigeru , Sakai Sanae , Michimori Yuta , Sumida Tomomi , Chikaraishi Yoshito , Atomi Haruyuki , Nunoura Takuro
Published: September 2023

Microfluidic capillary electrophoresis-mass spectrometry (CE-MS) is a rapid and highly accurate method to determine isotopomer patterns in isotopically labeled compounds. Here, we developed a novel method for tracer-based metabolomics using CE-MS for underivatized proteinogenic amino acids. The method consisting of a ZipChip CE system and a high-resolution Orbitrap Fusion Tribrid mass spectrometer allows us to obtain highly accurate data from 1 μL of 100 nmol/L mol amino acids comparable to a mere 1 × 104-5prokaryotic cells. To validate the capability of the CE-MS method, we analyzed 16 protein-derived amino acids from a methanogenic archaeonMethanothermobacter thermautotrophicusas a model organism, and the mass spectra showed sharp peaks with low mass errors and background noise. Tracer-based metabolome analysis was then performed to identify the central carbon metabolism inM. thermautotrophicususing13C-labeled substrates. The mass isotopomer distributions of serine, aspartate, and glutamate revealed the co-occurrence of the Wood-Ljungdahl pathway and an incomplete reductive TCA cycle for carbon fixation. In addition, biosynthesis pathways of 15 amino acids were constructed based on the mass isotopomer distributions of the detected protein-derived amino acid, genomic information, and public database. Among them, the presence of the alternative enzymes of alanine dehydrogenase, ornithine cyclodeaminase, and homoserine kinase was suggested in the biosynthesis pathways of alanine, proline, and threonine, respectively. To our knowledge, the novel13C tracer-based metabolomics using CE-MS is the most efficient method to identify central carbon metabolism and amino acid biosynthesis pathways and is applicable to in any kind of isolated microbe.
Construction of Single-Copy Fluorescent Protein Fusions by One-Step Recombineering
Authors: Balbontín Roberto , Figueroa-Bossi Nara , Bossi Lionello
Published: September 2023

We describe a simple recombineering-based procedure for generating single-copy gene fusions to superfolder GFP (sfGFP) and monomeric Cherry (mCherry). The open reading frame (orf) for either protein is inserted at the targeted chromosomal location by λ Red recombination using an adjacent drug-resistance cassette (kanorcat) for selection. The drug-resistance gene is flanked by flippase (Flp) recognition target (FRT) sites in direct orientation, which allows removal of the cassette by Flp-mediated site-specific recombination once the construct is obtained, if desired. The method is specifically designed for the construction of translational fusions producing hybrid proteins with a fluorescent carboxyl-terminal domain. The fluorescent protein-encoding sequence can be placed at any codon position of the target gene's mRNA where the fusion produces a reliable reporter for gene expression. Internal and carboxyl-terminal fusions to sfGFP are suitable for studying protein localization in bacterial subcellular compartments.
GeneratingAedes aegyptiMutant Strains with Transgenic Cas9
Authors: Sun Ruichen , Raban Robyn , Akbari Omar S.
Published: September 2023

Here, we provide a protocol for generatingAedes aegyptimutant strains via end-joining (EJ) or homology-directed repair (HDR) mechanisms using genetically encoded Cas9.
Retrospective Review of and Introduction to the Analysis of Mosquito Optomotor Responses
Authors: Vinauger Clément , Riffell Jeffrey A.
Published: September 2023

Adult hematophagous female mosquitoes require nutrients and proteins from vertebrate blood to produce progeny. To find these hosts, mosquitoes rely on olfactory, thermal, and visual cues. Among these sensory modalities, vision has received far less attention than olfaction, in part because of a lack of experimental tools providing sufficient control on the delivery of visual stimuli and the recording of mosquito responses. Although free-flight experiments (e.g., wind tunnel and cage) ensure higher ecological relevance and allow the observation of more natural flight dynamics, tethered flight assays offer a greater level of control on the suite of sensory stimuli experienced by mosquitoes. In addition, these tethered assays provide a stepping stone toward understanding the neural underpinnings of mosquito optomotor behavior. Advances in computer vision tracking systems and programmable light-emitting diode displays have permitted significant discoveries in models such as the flyDrosophila melanogaster. Here, we introduce the use of these methods with mosquitoes.
CRISPR–Cas9 Methods and Key Considerations in the Production ofAedes aegyptiMutant Strains
Authors: Sun Ruichen , Raban Robyn , Akbari Omar S.
Published: September 2023

Since the characterization of the CRISPR–Cas9 system in prokaryotes, it has become the prime choice in gene editing because of its exceptional flexibility, ease of use, high efficiency, and superior specificity. As a result, CRISPR–Cas9-mediated gene-editing technologies have enabled researchers not only to engineer transgenic animal strains with site-directed insertions more efficiently but also to generate desired mutants for previously intractable species. One such species is the invasive yellow fever mosquito,Aedes aegypti, which is notorious for its ability to transmit many blood-borne human pathogens. Methods for developing new transgenic strains of the yellow fever mosquito may aid in the effort to control its populations and provide significant benefits for the public. Here, we provide an overview of injection and noninjection methods for generating transgenic mosquitoes and also highlight important experimental design features.
DNA Recombineering Applications
Authors: Figueroa-Bossi Nara , Balbontín Roberto , Bossi Lionello
Published: September 2023

The ability to manipulate the bacterial genome is an obligatory premise for the study of gene function and regulation in bacterial cells. The λ red recombineering technique allows modification of chromosomal sequences with base-pair precision without the need of intermediate molecular cloning steps. Initially conceived to construct insertion mutants, the technique lends itself to a wide variety of applications including the creation of point mutants, seamless deletions, reporter, and epitope tag fusions and chromosomal rearrangements. Here, we introduce some of the most common implementations of the method.
Fighting Flies: Quantifying and AnalyzingDrosophilaAggression
Authors: Fernandez Maria P. , Trannoy Severine , Certel Sarah J.
Published: September 2023

Aggression is an innate behavior that likely evolved in the framework of defending or obtaining resources. This complex social behavior is influenced by genetic, environmental, and internal factors.Drosophila melanogasterremains an effective and exciting model organism with which to unravel the mechanistic basis of aggression due to its small but sophisticated brain, an impressive array of neurogenetic tools, and robust stereotypical behavioral patterns. The investigations of many laboratories have led to the identification of external and internal state factors that promote aggression, sex differences in the patterns and outcome of aggression, and neurotransmitters that regulate aggression.
The structure of AcrIC9 revealing the putative inhibitory mechanism of AcrIC9 against the type IC CRISPR–Cas system
Authors: Kang Yong Jun , Kim Ju Hyeong , Lee Gwan Hee , Ha Hyun Ji , Park Young-Hoon , Hong Eunmi , Park Hyun Ho
Published: September 2023

CRISPR–Cas systems are known to be part of the bacterial adaptive immune system that provides resistance against intruders such as viruses, phages and other mobile genetic elements. To combat this bacterial defense mechanism, phages encode inhibitors called Acrs (anti-CRISPR proteins) that can suppress them. AcrIC9 is the most recently identified member of the AcrIC family that inhibits the type IC CRISPR–Cas system. Here, the crystal structure of AcrIC9 from Rhodobacter capsulatus is reported, which comprises a novel fold made of three central antiparallel β-strands surrounded by three α-helixes, a structure that has not been detected before. It is also shown that AcrIC9 can form a dimer via disulfide bonds generated by the Cys69 residue. Finally, it is revealed that AcrIC9 directly binds to the type IC cascade. Analysis and comparison of its structure with structural homologs indicate that AcrIC9 belongs to DNA-mimic Acrs that directly bind to the cascade complex and hinder the target DNA from binding to the cascade.
Ownership concentration and cost of equity in Pakistan: the moderating role of disclosure and governance quality
Authors: Sajid Memoona , Shabbir Hashmat , Safdar Raheel
Published: September 2023

Purpose

The purpose of this study is to examine the relationship between the ownership concentration and cost of equity of firms in Pakistan context. Moreover, this study also investigates how the presence of disclosure quality and governance quality affects the relationship between ownership concentration and the cost of equity of firms.

Design/methodology/approach

Data are collected from six non-financial sectors listed on Pakistan Stock Exchange during the period of 2015–2019. This study uses pooled ordinary least square (OLS) method to validate the proposed hypothesis in STATA.

Findings

The study found a positive and significant relationship between ownership concentration and cost of equity. The results also show that better disclosure and governance quality negatively moderates the relationship between ownership concentration and cost of equity.

Practical implications

The findings of this study will help firm managers to implement a high level of disclosure and governance quality in firms to reduce agency problems which will further help a firm in reducing the firm's cost of equity. Furthermore, this study is valuable for practitioners regarding thinking about the process of designing ownership structures to protect minority shareholders' rights, especially in emerging markets.

Originality/value

The novelty of this study is having better disclosure quality and more board independence members helps firms with higher ownership concentration in reducing the cost of equity.
An empirical investigation on the deployment of operational excellence in SMEs
Authors: Mahato Satyajit , Dixit Amit Rai , Agrawal Rajeev , Antony Jiju , Garza-Reyes Jose Arturo , Jamwal Anbesh
Published: September 2023

Purpose

This study investigates the quantitative aspect of the various strains of operational excellence (OE) and competitive-potential (CP) in the SME sector. It has five steps, i.e., identifying the key performance constructs of OE and their hypothesized relationship pattern from literature, validating these constructs through factor analysis, formalizing their empirical relationships by structural-equation-modeling (SEM), path analysis of performance constructs with the empirical results, and lastly proposing a framework for OE deployment in SMEs.

Design/methodology/approach

Data for the deployment scores of operational excellence procedures (OEPs) were collected through a structured questionnaire survey. Nine hundred participants from a stratified random sample were approached for the survey, and 473 responses were received. Sample stratification was based on Gender, Education, Experience, Position, Department and Industry. Respondents had 5–30 years of experience managing manufacturing operations, holding the manager position and above.

Findings

The path analysis of the structural model provides unique insights into OE's practical aspects in SMEs (small and medium enterprises). For example, Contractual-conformance and Process-efficiency play pivotal roles as both have a significant positive impact on CP. Supplier efficacy, Consistency and Product-excellence do not improve CP unless mediated by Contractual-conformance or Process-efficiency.

Research limitations/implications

The study provides important implications for academia, policymakers and managers. The study identifies and validates the operational excellence key performance practices and proposes a framework for manufacturing organizations. SME managers can follow the framework to develop effective operational excellence strategies to help them achieve their organizational goals. Additionally, the study emphasizes the need for continuous culture in SMEs, which will help to support operational excellence deployment. Overall, the implications presented in the study will help SMEs to enhance their competitiveness and operational performance.

Originality/value

The study explores the empirical investigation of the operational excellence deployment in SMEs. The study uses a mixed method approach for research design, including qualitative and quantitative approaches, and uses SEM to test the proposed framework. Validation of OE's six key performance constructs and establishing their empirical relation is an attempt to advance the Operations excellence theory. Unlike large enterprises, SMEs demonstrate an incohesive response to the practices pertaining to Supplier efficacy, Consistency and Product-excellence. This unique response pattern requires special treatment, which is incorporated into the proposed framework.
The influence of leader inclusiveness on learning from failure in the hotel industry
Authors: Alzyoud Sultan , Abuzaid Ruba
Published: September 2023

Purpose

Inevitably, there is no free-mistakes organization. The hotel industry can be considered a dynamic and labor-intensive sector where mistakes can occur frequently. Therefore, learning from failure or mistakes is considered a crucial component of learning in the workplace. This study aims to explore leaders' behaviors that can encourage employees to engage in learning from failure endeavors.

Design/methodology/approach

This is a qualitative study where five semi-structured interviews were undertaken with heads of departments in four-and five-star hotels in Manchester, the UK. Thematic analysis was performed to analyze the collected data.

Findings

The results revealed that three leader behaviors were suggested to encourage employee learning from failure in hotels, namely: being open and accessible to employees, encouraging them to speak up and share their experiences, particularly their mistakes, and giving them constructive feedback instead of criticisms. These behaviors were found to be related to a construct in past studies called leader inclusiveness.

Originality/value

This is an exploratory study that tries to enhance the understanding of what encourages learning from failure at work, particularly in the hotel industry where this has received little attention.
Geometry error compensation using multiply laser sensors: a case study
Authors: Zhang Xinyu , Ge Liling
Published: September 2023

Purpose

A multi-laser sensors-based measurement instrument is proposed for the measurement of geometry errors of a differential body and quality evaluation. This paper aims to discuss the aforementioned idea.

Design/methodology/approach

First, the differential body is set on a rotation platform before measuring. Then one laser sensor called as “primary sensor”, is installed on the intern of the differential body. The spherical surface and four holes on the differential body are sampled by the primary sensor when the rotation platform rotates one revolution. Another sensor called as “secondary sensor”, is installed above to sample the external cylinder surface and the planar surface on the top of the differential body, and the external cylinder surface and the planar surface are high in manufacturing precision, which are used as datum surfaces to compute the errors caused by the motion of the rotation platform. Finally, the sampled points from the primary sensor are compensated to improve the measurement accuracy.

Findings

A multi-laser sensors-based measurement instrument is proposed for the measurement of geometry errors of a differential body. Based on the characteristics of the measurement data, a gradient image-based method is proposed to distinguish different objects from laser measurement data. A case study is presented to validate the measurement principle and data processing approach.

Research limitations/implications

The study investigates the possibility of correction of sensor data by the measurement results of multiple sensors to improving measurement accuracy. The proposed technique enables the error analysis and compensation by the geometric correlation relationship of various features on the measurand.

Originality/value

The proposed error compensation principle by using multiple sensors proved to be useful for the design of new measurement device for special part inspection. The proposed approach to describe the measuring data by image also is proved to be useful to simplify the measurement data processing.
Green entrepreneurial orientation and knowledge creation process as enablers of green innovation performance: the moderating role of resource orchestration capability
Authors: Idrees Hisham , Xu Jin , Andrianarivo Andriandafiarisoa Ralison Ny Avotra
Published: September 2023

Purpose

The current study aims to ascertain how green entrepreneurial orientation (GEO) affects green innovation performance (GIP) through the mediating mechanism of the knowledge creation process (KCP) and whether or not these associations can be strengthened or hampered by the moderating impacts of resources orchestration capabilities (ROC).

Design/methodology/approach

The research used data from managers at various levels in 154 manufacturing enterprises in Pakistan to evaluate the relationships among the constructs using hierarchical regression analysis and moderated mediation approach.

Findings

The study indicates that GEO substantially impacts firms' GIP. GEO and GIP's relationship is partially mediated by two KCP dimensions: knowledge integration (KI) and knowledge exchange (KE). Furthermore, ROC amplifies not only the effects of GEO on KE but also the effects of KE on GIP. The moderated mediation results demonstrate that KE has a greater mediating influence on GEO and GIP when ROC is higher.

Research limitations/implications

To better understand GEO's advantages and significance, future studies should look into the possible moderating mechanisms of environmental, organizational culture/green capability in the association between GEO, KCP and GIP.

Practical implications

The research helps expand the field of green entrepreneurship and GIP literature by providing a deeper knowledge of GEO and offering insight into how to boost GI in manufacturing firms.

Originality/value

This research helps fill in knowledge gaps in the field by delving further into the mechanisms by which GEO promotes GIP, both directly and indirectly, via the mediating role of KCP and the moderating impacts of ROC.
Connecting higher education and renewable energy to attain sustainability for BRICS countries: A climate Kuznets curve perspective
Authors: Iqbal Mubasher , Ul-Durar Shajara , Arshed Noman , Shahzad Khuram , Ayub Umer
Published: September 2023

Purpose

Increased trapped heat in the atmosphere leads to global warming and economic activity is the primary culprit. This study proposes the nonlinear impact of economic activity on cooling degree days to develop a climate Kuznets curve (CKC). Further, this study explores the moderating role of higher education and renewable energy in diminishing the climate-altering effects of economic activity.

Design/methodology/approach

All the selected BRICS economies range from 1992 to 2020. The CKC analysis uses a distribution and outlier robust panel quantile autoregressive distributed lagged model.

Findings

Results confirmed a U-shaped CKC, controlling for population density, renewable energy, tertiary education enrollment and innovation. The moderating role of renewable energy and education can be exploited to tackle the progressively expanding climate challenges. Hence, education and renewable energy intervention can help in reducing CKC-based global warming.

Research limitations/implications

This study highlighted the incorporation of climate change mitigating curriculum in education, so that the upcoming economic agents are well equipped to reduce global warming which must be addressed globally.

Originality/value

This study is instrumental in developing the climate change-based economic activity Kuznets curve and assessing the potential of higher education and renewable energy policy intervention.