bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantifying acute kidney injury in an Ischaemia-Reperfusion Injury mouse model using deep-learning-based semantic segmentation in histology
Authors: Luchian Andreea , Cepeda Katherine Trivino , Harwood Rachel , Murray Patricia , Wilm Bettina , Kenny Simon , Pregel Paola , Ressel Lorenzo
Published: August 2023

This study focuses on ischaemia-reperfusion injury (IRI) in kidneys, a cause of acute kidney injury (AKI) and end-stage kidney disease (ESKD). Traditional kidney damage assessment methods are semi-quantitative and subjective. This study aims to use a convolutional neural network (CNN) to segment murine kidney structures after IRI, quantify damage via CNN-generated pathological measurements, and compare this to conventional scoring. The CNN was able to accurately segment the different pathological classes, such as Intratubular casts and Tubular necrosis, with an F1 score of over 0.75. Some classes, such as Glomeruli and Proximal tubules, had even higher statistical values with F1 scores over 0.90. The scoring generated based on the segmentation approach statistically correlated with the semiquantitative assessment (Spearman’s rank correlation coefficient=0.94). The heatmap approach localised the intratubular necrosis mainly in the outer stripe of the outer medulla, while the tubular casts were also present in more superficial or deeper portions of the cortex and medullary areas. This study presents a CNN model capable of segmenting multiple classes of interest, including acute IRI-specific pathological changes, in a whole mouse kidney section and can provide insights into the distribution of pathological classes within the whole mouse kidney section.
Imperfect Financial Markets and Investment Inefficiencies
Authors: Albagli Elias , Hellwig Christian , Tsyvinski Aleh
Published: August 2023

We analyze the consequences of noisy information aggregation for investment. Market imperfections create endogenous rents that cause overinvestment in upside risks and underinvestment in downside risks. In partial equilibrium, these inefficiencies are particularly severe if upside risks are coupled with easy scalability of investment. In general equilibrium, the shareholders’ collective attempts to boost value of individual firms leads to a novel externality operating through price that amplifies investment distortions with downside risks but offsets distortions with upside risks. (JEL D21, D25, D83, G14, G32, G41)
Assessing the reliability of CBCT-based AI-generated STL files in diagnosing osseous changes of the mandibular condyle: a comparative study with ground truth diagnosis
Authors: Orhan Kaan , Sanders Alex , Ünsal Gürkan , Ezhov Matvey , Mısırlı Melis , Gusarev Maxim , İçen Murat , Shamshiev Mamat , Keser Gaye , Namdar Pekiner Filiz , Golitsyna Maria , Önder Merve , Manulis David , Atakan Cemal
Published: August 2023

Objectives:

This study aims to evaluate the reliability of AI-generated STL files in diagnosing osseous changes of the mandibular condyle and compare them to a ground truth (GT) diagnosis made by six radiologists.

Methods:

A total of 432 retrospective CBCT images from four universities were evaluated by six dentomaxillofacial radiologists who identified osseous changes such as flattening, erosion, osteophyte formation, bifid condyle formation, and osteosclerosis. All images were evaluated by each radiologist blindly and recorded on a spreadsheet. All evaluations were compared and for the disagreements, a consensus meeting was held online to create a uniform GT diagnosis spreadsheet. A web-based dental AI software was used to generate STL files of the CBCT images, which were then evaluated by two dentomaxillofacial radiologists. The new observer, GT, was compared to this new STL file evaluation, and the interclass correlation (ICC) value was calculated for each pathology.

Results:

Out of the 864 condyles assessed, the ground truth diagnosis identified 372 cases of flattening, 185 cases of erosion, 70 cases of osteophyte formation, 117 cases of osteosclerosis, and 15 cases of bifid condyle formation. The ICC values for flattening, erosion, osteophyte formation, osteosclerosis, and bifid condyle formation were 1.000, 0.782, 1.000, 0.000, and 1.000, respectively, when comparing diagnoses made using STL files with the ground truth.

Conclusions:

AI-generated STL files are reliable in diagnosing bifid condyle formation, osteophyte formation, and flattening of the condyle. However, the diagnosis of osteosclerosis using AI-generated STL files is not reliable, and the accuracy of diagnosis is affected by the erosion grade.
Impact of brand equity and service quality on the reputation of universities and students’ intention to choose them: The case of IIUM and UIN
Authors: Rizard Sylvia Rozza , Waluyo Bambang , Jaswir Irwandi
Published: August 2023

Background:Numerous studies have been carried out on the impacts of brand equity and service quality of higher education institutions (HEIs) on their reputation and students’ satisfaction. This research aimed to compare the impact of brand equity and service quality on universities’ reputations, namely Universitas Islam Negeri (UIN) in Indonesia and International Islamic University Malaysia (IIUM) in Malaysia, and Indonesian students’ intention to choose the universities, which is moderated by study expense (price). UIN and IIUM are HEIs with a similar university concept, and Indonesian students have recently shown a high interest in them. The two universities have faculties not only in the field of Islamic studies but in general fields of studies as well, which are usually held by non-Islamic Universities. Therefore, their competitiveness against non-Islamic universities, especially the University of Indonesia (UI) has increased.

Methods:The statistical measurement tool used was structural equation modeling (SEM). The number of items stated in the questionnaire was 45. Therefore, minimum data to be collected were 5 × 45 or 225 which rounded up to 228 from Indonesian students at UIN and IIUM (114 UIN students, and 114 Indonesian student respondents from IIUM).

Results:The study results show that the universities’ reputations are strongly affected by their brand equity and service quality, which then affect students’ intention to choose the universities. Students had a higher intention to choose IIUM than UIN. The limitation of this research is that the effect of study expense on the intention of Indonesian students to study at UIN or IIUM has not yet been conducted. It will be conducted in the next study.

Conclusions:These results are expected to be useful to UIN, IIUM, and especially Politeknik Negeri Jakarta (PNJ) in determining a strategy to enhance their reputations and the intention of Indonesian students to study there.
Methylene blue sentinel lymph node biopsy for breast cancer learning curve in the COVID-19 era: How many cases are enough?
Authors: Azhar Yohana , Dewayani Birgitta M. , Lukman Kiki
Published: August 2023

Background: Sentinel lymph node biopsy (SLNB) is now the gold standard for early breast cancer with clinically negative lymph nodes (N0). According to the Indonesian Board-Certified oncologist surgeon, the learning curve for evaluating fellow breast surgeons to achieve this competency could have been shorter due to the COVID-19 pandemic. This study aims to see if the learning curve for sentinel lymph node (SLN) identification can be shortened.

Methods: Trainee breast surgeons were taught to perform SLNB on breast cancer patients. Intraoperative assessment and completion of axillary lymph node dissection (ALND) were performed in the first setting for standardization with the attending surgeon. Sentinel lymph node identification was plotted on cumulative sum chart (CUSUM) limitations for evaluating the variability competency between the attending and trainee surgeons based on a target identification rate of 85%.

Results: We concluded that CUSUM charts are the best tools currently available for assessing psychomotor learning SLNB. According to a CUSUM chart based on a reasonable set of parameters, the learning curve for SLNB using methylene blue dye is reached after 4-5  consecutive positively detected SLN.

Conclusion: CUSUM Chart showed that experienced breast surgeons have completed the SLNB learning curve after 4-5 successful methylene blue attempts. In the future, this learning curve analysis can be applied to trainee breast surgeons by utilizing a proxy measure for failure, such as failure to identify the SLN.
Optimal control model of human-to-human transmission of monkeypox virus
Authors: Ackora-Prah Joseph , Okyere Samuel , Bonyah Ebenezer , Adebanji Atinuke Olusola , Boateng Yaw
Published: August 2023

Background: The number of monkeypox cases is rising globally, but it’s unclear how many instances there will be in the near future. The disease has been one of the major problems for sub-Saharan Africans in the past few years. This study seeks to suggest optimal strategies for curbing the disease in Ghana and preventing future occurrences.

Methods: A deterministic mathematical model incorporating optimal controls has been developed in this research to investigate the transmission of the monkeypox virus. The model’s fundamental properties such as positivity and boundedness of solution, and basic reproduction number have been examined. In order to assess the efficacy of two preventative control strategies—public education and vaccination—optimal controls were included in the model and Pontragyin’s maximum principle was used to characterize the model.

Results: The disease was observed to be not endemic with infection going extinct after ten days. The Monkeypox-related deaths were insignificant. The optimal strategies revealed that public education had less of an effect on those who were vulnerable than the vaccine control strategy. However, both approaches were successful in reducing the number of people who were exposed to the illness and reducing the number of fatalities. Vaccination reduced the number by 32.35% and public education by 50% at the peak of the exposed phase. Additionally, vaccination increases a person’s immunity, which speeds up their recovery.

Conclusions: A deterministic classical model incorporating optimal controls was proposed to study the monkeypox virus dynamics in a population. The disease is not endemic, which is explained by the model’s basic reproduction number, which was less than unity. Based on the findings of this study, we advise the use of both strategies in controlling the disease.
A framework for doctoral education in developing students’ mental well-being by integrating the demand and resources of the program: An integrative review
Authors: Acharya Vrinda , Rajendran Ambigai , Shenoy Sandeep
Published: August 2023

Background: Research on doctoral students’ mental well-being has gained importance in recent years. The findings of such studies were uncertain about the critical demand and resource of a doctoral program that largely influence students’ mental health. This review aims to integrate the literature to bring out the nature, importance and relationship between differentiated demands, contextual and personal resource, and doctoral students’ well-being. 

Methods: An integrative review was conducted based on the five-stage structure of Whittemore and Knafl. The study identified 45 articles published from 2000 onwards following the Joanna Briggs Institute quality evaluation criteria and PRISMA reporting guidelines for selecting eligible articles. 

Results: The integrative review findings disclose that the differentiated demand of doctoral program were categorized into challenge-hindrance demand. This demand experienced by doctoral students were grouped as ambiguity in doctoral program structure, resource inadequacy, workload, complexity, and responsibility. In addition, institutional support, research supervisory support, and intrinsic motivation were treated as essential resource to mitigate the effects of the demands of the doctoral program.

Conclusions: An integrated conceptual model was built exclusively for doctoral programs and suggests that the universities and supervisors design and structure healthy, constructive doctoral programs. As an outcome of the review, differentiated demands, contextual, personal resources at the doctoral education and mental well-being of students are supported by the Transactional Model of Stress and Coping, Conservation of Resources, Causality Orientations Theory and Basic Psychological Need Theory respectively. The current review is an initial attempt to synthesize challenge-hindrance demands and contextual-personal resources in determining the mental well-being of doctoral students.
Case Report: IgG4-related kidney disease complicated by interstitial pneumonia
Authors: Mima Akira , Lee Rina , Murakami Ami , Gotoda Hidemasa , Akai Ryosuke , Lee Shinji
Published: August 2023

Immunoglobulin G4 (IgG4)-related disease is a systemic inflammatory disorder characterized by tubulointerstitial nephritis with IgG4-positive plasma cell infiltration. We report the case of an 84-year-old male who presented with a history of dyspnea on exertion and cough. The lymph nodes were palpated in the axilla. Urinalysis revealed mild proteinuria and increased levels of NAG and β2-microglobulin. Blood tests showed hyperglobulinemia with a marked elevation of serum IgG4 levels. Chest computed tomography showed bilateral ground-glass and reticular opacities in the lower and peripheral portions of the lungs. Ga-67 scintigraphy showed kidney uptake.

The patient was diagnosed with IgG4-related kidney disease based on the renal pathology indicative of typical tubulointerstitial nephritis with extensive IgG4-positive plasma cell infiltration. The patient was treated with prednisolone and showed a prompt response in his clinical condition. The patient achieved normalization of serum IgG4 levels 6 months after the initiation of treatment. Although IgG4-related disease is thought to be potentially associated with organ fibrosis, there are few reports on combination of interstitial pneumonia and IgG4-related kidney disease. Our case report presents a possible pattern of IgG4-related disease.
Case Report: Idiopathic pleuroparenchymal fibroelastosis
Authors: Daboussi Selsabil , Lenda Ben Hmida , Mhamedi Samira , Nouha Boubaker , Aichaouia Chiraz , Ayadi Aida , Moatemri Zied
Published: August 2023

Background: Idiopathic pleuroparenchymal fibroelastosis (IPPFE) is a very rare and a slowly conspicuous progressing chronic lung disease, which usually involves the upper lobes of the lung. This unusual disease, first recognized as a rare idiopathic interstitial pneumonia in 2013, is characterized by dense fibrosis of the visceral pleura and the subjacent lung parenchyma accompanied by elastosis predominating in the subpleural alveolar walls. In the interest of improving our understanding of this uncommon disease, we report a case of IPPFE established by pathology results.

Case report: A 73-year-old male patient, smoker, with a medical history of chronic obstructive pulmonary disease, presented since January 2022 with a gradual worsening of dyspnea on exertion and productive cough with weight loss. The chest X-ray detected a thoracic distention. The chest high resolution computed tomography revealed biapical subpleural parenchymatous condensations with tractive bronchiectasis and pleural retraction in the right upper lobe and diffuse bilateral cento-lobular emphysema. A scan-guided trans-parietal lung biopsy showed lung parenchyma tattooed with anthracosic deposits, largely remodeled by fibrous tissue, intermingled with numerous wavy and refractive dyselastotic structures in polarized light. The orcein staining confirmed the presence of excess elastosic fibers within these lesions. All etiological investigations were negative. His lung function studies revealed a reversible obstructive ventilatory disorder. Following a multidisciplinary discussion, the diagnosis of IPPFE was confirmed on the basis of the distribution in the upper lungs on chest computed tomography combined with pathology pattern.

Conclusions: This case emphasizes the atypical misleading radiological presentation of IPPFE and the key role of pathological results in establishing the diagnosis. Hence, further studies are needed to improve our understanding of this uncommon disease and to establish clear-cut guidelines for IPPFE diagnosis and management.
Comparison of root end sealing ability of three retrograde filling materials in teeth with root apices resected at 900 using dye penetration method under fluorescent microscope
Authors: Chaudhari Dr. Payal , Chandak Manoj , Patel Dr. Aditya
Published: August 2023

Background: The main factor contributing to surgical endodontic dissatisfaction is an inadequate seal at the apex. The material used for retrograde filling should prevent contaminants from penetrating periradicular tissue. So the objective of this study was to evaluate and compare the ability of Mineral Trioxide Aggregate (MTA), Zirconomer and bioactive bone cement to seal the root end as retrograde filling material with apices resected at 900 angles using dye penetration method under fluorescent microscope.

Methods: 36 extracted teeth samples were cut at Cementoenamel junction horizontally. Following the customary protocols of, cleaning, shaping and obturation with gutta percha and AH Plus sealer, resection of samples was done 3mm at the apical end at 90 degree angle along the long axis of the tooth with the help of diamond disc. A depth of 3mm of root end cavity was made with diamond coated ultrasonic surgical tip. The samples were randomly allocated in 3 groups: Group I: MTA ; Group II : Zirconomer; Group III: Bioactive Bone Cement . Coating of nail varnish was done with the roots except at the tip. Each material was compacted in the retrocavity using small pluggers. All the retrofilled samples were kept in acridine orange for 24 hours, following which cleaning & bucco-lingual sectioning (vertical) was carried out. Confocal laser scanning fluorescent microscope was used for checking the dye penetration in these samples thereby evaluating sealing ability.

Results: Group III (Bioactive Bone Cement) had the highest root end sealing ability with mean (1.4 ± 0.51) followed by Group I (MTA) (2.3 ± 0.65) and lastly Group II (Zirconomer) (4.1 ± 0.57) as root end filling material with apices resected at 900 angle using dye penetration method under fluorescent microscopy which were statistically significant.

Conclusions: Bioactive Bone cement can be recommended as an acceptable retrograde filling material.
Symptoms trend and challenges in dental practice during delta variance COVID-19 pandemic in Indonesia: Google Trends Analysis
Authors: Hasan Faizul , Mayasari Noor Rohmah , Salamanca Eisner , Dorj Odontuya , Satria Rahmat Dani , Latief Kamaluddin , Sujarwadi Mokh. , Budi Hendrik Setia
Published: August 2023

Background: The COVID-19 pandemic has grown to be a serious issue on a global scale. Dental care is one of the industries affected by COVID-19. The surveillance utilizing lifetime data, however, is still not clear. The purpose of this study was to use Google Trends (GT) analysis to examine symptom trends and challenges during the COVID-19 outbreak in Indonesia.

Methods: Covid-19 cases retrieve from Our World in Data. The cases were collected between 1 April 2021-30 September 2021. The GT was used to discover Indonesian relative search volume (RSVs) covering the timeframe of the first outbreak covid-19 pandemic in Indonesia on 1 March 2020 until 13 February 2022. The duration of the search was chosen to reflect the relative popularity of the keywords "symptoms and dentistry practice challenge-related terms" and "coronavirus". Results: We observed that there was a significant and positive correlation between the COVID-19 daily case using GT RSV data and the COVID-19 case from Our World in Data. The COVID-19 daily case had a strong correlation with search terms related to symptoms (such as fever, sore throat, flu, toothache, and cough), drugs (such as ibuprofen, paracetamol, demacolin, bodrex, and antibiotic), and health management (such as self-isolation and telemedicine).

Conclusion: Using GT may be helpful to observe the current symptoms trends as well as its challenge tendencies as a surveillance tool for a continuing pandemic like COVID-19. GT should be considered and used as it has the potential to be a powerful digital epidemiology tool that can provide more insight into disease dynamics.
The total factor productivity growth of health systems in African least developed countries
Authors: Musoke Edward , Lule Yawe Bruno , Ddumba Ssentamu John
Published: August 2023

Background: Given the several health policy reforms in various countries in the Sustainable Development Goals (SDGs) era, the need for efficient and productive health systems has become of great concern. This is even more urgent in African Least Developed Countries (African LDCs) that need to improve the health of their populations. Thus, the objective of this study is to assess the total factor productivity growth of health systems of 29 African Least Developed Countries for the 2008-2018 period.

Methods: The study uses data from the World Bank and the World Health Organization. Using the Data Envelopment Analysis (DEA) Malmquist index, the inputs that were used in the study included domestic general government health expenditure, domestic private health expenditure, external health expenditure and out of pocket health expenditure while the outputs were life expectancy at birth, maternal mortality rate, under five mortality rate, and infant mortality rate.

Results: Sixteen African LDCs registered progress in the total factor productivity growth of their health systems while thirteen registered a decline the total factor productivity growth of their health systems. Overall, there was 0.3% average increase in total factor productivity growth of health systems in African LDCs. This was attributed to a 1.2% increase in technical efficiency change and a 0.9% average decrease in the technical change of health systems in African LDCs.

Conclusions: African LDCs with less productive health systems are advised to bench mark the policies of African LDCs with productive health systems.
Study protocol for supplementation of single high dose Vitamin D in deficient critically ill children and assessment of their short-term outcome: An open label randomized control trial
Authors: Vagha Keta , Lohiya Sham , Vagha Jayant , Vagha Sunita , Taksande Amar , Chaudhary Richa
Published: August 2023

Vitamin D is a fat-soluble vitamin and is classically considered to play a major role in bone metabolism and maintaining Calcium and phosphorus equilibrium. With progressing research, other roles of Vitamin D are surfacing. The pleotropic functions of Vitamin D regulate cell proliferation, differentiation, apoptosis, and angiogenesis. In critically ill children, Vitamin D deficiency is associated with poor outcomes in the form of increased PICU stay, increased duration of mechanical ventilation, higher rate of Ventilator Associated Pneumonias, increased incidence of sepsis, higher intensive care scores and increased incidence of end organ dysfunction. With this background, we aim to conduct an open label Randomized Control Trial to study the short-term outcome of Vitamin D deficient critically ill children after supplementation of a single high dose oral Vitamin D. This will be an open label randomized control trial conducted at a tertiary care hospital in central India. Children aged 1 month to 18 years, admitted in the pediatric intensive care unit with Serum Vitamin D level less than 20 ng/dL will be the study group. These children will be randomized into two groups as per the computer-generated randomization. Group A will receive standard treatment protocol with 10,000 IU/Kg to 400,000 IU (maximum) Vitamin D via mouth or nasogastric tube, whereas Group B will receive standard treatment protocol. Urinary calcium-creatinine ratio will be done on day 3 in Group A to check for hypervitaminosis D. The outcome of both the groups will be assessed. All the data will be added to a Microsoft Excel sheet. Results and interpretation will be determined on the basis of the obtained observation.

Trial registration: CTRI/2022/10/046556.
Case Report: Standard rehabilitation protocol for complex tibial plateau fracture associated with fibular head fracture managed with plate osteosynthesis
Authors: Boob Manali A. , Phansopkar Pratik , Somaiya Kamya
Published: August 2023

Schatzker fracture belongs to the tibial plateau fracture. This fracture is frequently characterized by excessive trauma, such as a fall from a terrific height or an automobile collision. They are identified by a vertical break in the tibial plateau, which disturbs the joint surface and surrounding tissues. A schatzker type six fracture is a complex fracture that is difficult to manage conservatively and typically requires surgery to reestablish articular realignment and integrity. The purpose of this study is to examine the rehabilitation method and actual outcomes of a 41-year-old male patient who had a tibial plateau fracture as well as a fibular head fracture. This case study shows the need for a comprehensive rehabilitation program in assisting individuals with this specific fracture pattern to achieve their maximum functional potential. The patient undertook a rehabilitation program that comprised several therapy interventions such as range-of-motion training, enhancing power, balance and proprioceptive training, gait re-training, and pain control measures. To assess the patient's progress, objective measurements such as goniometry, muscular strength by manual muscle testing, functional outcome ratings, and patient-reported outcomes were employed. As demonstrated by the case study, a comprehensive treatment approach is required to properly treat tibial plateau fractures in conjunction with fibular head fractures. The patient achieved a considerable and favorable affiliation with the therapy techniques and the outcome measures rating.
Nonlocal contrast calculated by the second order visual mechanisms and its significance in identifying facial emotions
Authors: Babenko Vitaly V. , Yavna Denis V. , Ermakov Pavel N. , Anokhina Polina V.
Published: August 2023

Background: Previously obtained results indicate that faces are /preattentively/ detected in the visual scene very fast, and information on facial expression is rapidly extracted at the lower levels of the visual system. At the same time different facial attributes make different contributions in facial expression recognition. However, it is known, among the preattentive mechanisms there are none that would be selective for certain facial features, such as eyes or mouth.

The aim of our study was to identify a candidate for the role of such a mechanism. Our assumption was that the most informative areas of the image are those characterized by spatial heterogeneity, particularly with nonlocal contrast changes. These areas may be identified /in the human visual system/ by the second-order visual /mechanisms/ filters selective to contrast modulations of brightness gradients.

Methods: We developed a software program imitating the operation of these /mechanisms/ filters and finding areas of contrast heterogeneity in the image. Using this program, we extracted areas with maximum, minimum and medium contrast modulation amplitudes from the initial face images, then we used these to make three variants of one and the same face. The faces were demonstrated to the observers along with other objects synthesized the same way. The participants had to identify faces and define facial emotional expressions.

Results: It was found that the greater is the contrast modulation amplitude of the areas shaping the face, the more precisely the emotion is identified.

Conclusions: The results suggest that areas with a greater increase in nonlocal contrast are more informative in facial images, and the second-order visual /mechanisms/ filters can claim the role of /filters/ elements that detect areas of interest, attract visual attention and are windows through which subsequent levels of visual processing receive valuable information.
Behind prison walls
Authors: Brown Clementine Reese
Published: August 2023

Clementine Rees Brown speaks to prisoner's ‘Nurse one’ to discuss the difference dental visits can make to a prisoners day.
‘Prisons? They are my best days at work’
Authors: Brown Clementine Reese
Published: August 2023

Clementine Rees Brown discusses the realities and triumphs of dental nursing in prisons with ‘Nurse two’.
Helping in every way possible
Authors: Lewis Amberley
Published: August 2023

Amberly Lewis discusses her role as a disability nurse at Guy's and St Thomas' Hospital.
Enhanced CPD: what you need to know
Authors: Sharma Priya
Published: August 2023

Priya Sharma summarises the various rules for ECPD for dental nurses.
The importance of the IPC lead
Authors: Bridges Glenys
Published: August 2023

Glenys Bridges details how the infection prevention and control (IPC) lead delivers safe and sustainable infection control.

Aim

This article aims to explore the essential requirements for effective infection prevention and show how these are fulfilled by infection control leads (IPC). It will identify the available resources and support available to maintain required Infection Prevention and Control standards and explain the importance of creating sustainable IPC through delegating and allocating roles and tasks.

Objectives

Develop the decon lead role to assure infector control outcomes. Specify the infection control leads role and job description. Define appropriate IPC training and development opportunities for the team.
Bad breath debunked
Authors: Hammond Andrea
Published: August 2023

Andrea Hammond breaks down the myths surrounding bad breath for patients.
A rewarding experience
Authors: Harding Jill
Published: August 2023

Jill Harding explores the many exciting opportunities to volunteer with Dentaid.
Application of a fiber Bragg grating temperature sensing method based on support vector regression optimized by a genetic algorithm for the decreasing external ambient temperature case
Authors: Li Yingjie , Chen Tao , Si Jinhai , He Yingsong , Gao Bo , Hou Xun
Published: August 2023

We studied the application of the fiber Bragg grating (FBG) temperature sensing method based on support vector regression optimized by a genetic algorithm (GA-SVR) for constant and decreasing external ambient temperature cases by simulation. The external ambient temperature could be retrieved from both the transient FBG wavelength and its corresponding change rate using GA-SVR, before the FBG temperature sensor reached the thermal equilibrium state with the external ambient temperature. FBG wavelengths and their corresponding change rates in the cases of FBG sensor temperatures higher and lower than the external ambient temperature were studied and used to construct the training data set. We found that there exist singularity points in the curves of the wavelength change rate when the FBG sensor temperature is higher than the external ambient temperature in some cases, which is different from the case where the FBG sensor temperature is lower than the external ambient temperature. Its application for sensing the constant and decreasing external ambient temperature in real time was demonstrated with an accuracy of 0.32°C in those two cases. It also indicates that for real applications of this temperature sensing method where the external ambient temperature varies randomly, the FBG sensor temperature changes rather than the external ambient temperature changes play the dominant role. What is more, the demodulation time was decreased to 0.002 s, which is approximately 0.05‱ of the time constant of the FBG temperature sensor. In other words, this method makes it possible to realize the external ambient temperature determination using a time smaller than the time constant of the FBG sensor. The high sensing accuracy and fast demodulation speed are crucial for future high-performance real-time FBG temperature sensing.
All optical operation of a superconducting photonic interface
Authors: Thiele Frederik , Hummel Thomas , McCaughan Adam N. , Brockmeier Julian , Protte Maximilian , Quiring Victor , Lengeling Sebastian , Eigner Christof , Silberhorn Christine , Bartley Tim J.
Published: August 2023

Quantum photonic processing via electro-optic components typically requires electronic links across different operation environments, especially when interfacing cryogenic components such as superconducting single photon detectors with room-temperature control and readout electronics. However, readout and driving electronics can introduce detrimental parasitic effects. Here we show an all-optical control and readout of a superconducting nanowire single photon detector (SNSPD), completely electrically decoupled from room temperature electronics. We provide the operation power for the superconducting detector via a cryogenic photodiode, and readout single photon detection signals via a cryogenic electro-optic modulator in the same cryostat. This method opens the possibility for control and readout of superconducting circuits, and feedforward for photonic quantum computing.
Propagating analysis of Airy beams via complex phase space and ray method
Authors: Huang Chaohong , Liu Xiao , Wang Mengyuan , Li Yanjing
Published: August 2023

A complex phase space and ray method is proposed to present intuitive interpretation of unique intensity profiles, parabolic accelerating trajectories, and distinctive phase shifts of Airy beam and its exponentially decaying version (i.e., finite-energy Airy beam). In the complex phase space, finite-energy Airy beam manifests itself as a complex parabolic phase space curve (PSC) which represents a cluster of light rays with complex wave vectors. The complex ray cluster converges to a complex parabolic caustic curve in complex coordinate space. For infinite-energy Airy beam, phase space, PSC, light ray and caustic curve change to real values. In the paraxial condition, Airy beams can maintain parabolic form of PSC and keep constant ray density, which guarantees the non-diffraction property of Airy beam and approximate non-diffraction property of finite-energy Airy beam. From the evolution of vertexes of parabolic PSC along a parabolic trajectory in phase space, one can also give the parabolic caustic curve for Airy beam and the complex parabolic caustic curve for exponentially decaying Airy beam. Further, the special phase and decay factors in the propagating solution of complex amplitude of Airy beams can be directly derived from the phase shifts of light ray cluster along transverse and longitudinal directions. The proposed phase space and ray method can present intuitive comprehension to distinctive propagating characteristics of Airy beams including intensity and phase, without resort to solving wave equation or diffracting integral formula.
Fano resonance in a microring resonator with a micro-reflective unit
Authors: Wang Jun , Lin Jie , Jin Peng , Liu Shutian , Zhou Keya
Published: August 2023

Fano resonance is considered to be a promising approach for integrated sensing. However, achieving and controlling Fano resonance lineshapes on ultra-compact chips remains a challenge. In this article, we propose a theoretic model based on the transfer matrix method (TMM) to quantitatively interpret the impact of a micro-reflective unit (MRU) etched in the straight waveguide of a microring resonator (MRR). Numerical calculations and FDTD simulations indicate that the size and position of the MRU can be used to control the Fano resonance lineshape. Since the MRU is etched in the coupling region, the reflection caused by the MRU will significantly enhance the intensity of the counter-clockwise (CCW) mode in the microring. When applied to a single nanoparticle sensing, clockwise (CW) and CCW modes will couple due to a single nanoparticles or rough cavity walls, resulting in a sharp shift and split of the Fano lineshape. The proposed model for single nanoparticle sensing is described by the scattering matrix, and the calculations show a well matches with FDTD simulations. The results show that the model proposed in this paper provides a new theoretical basis for controlling Fano resonance lineshape and presents a new approach for the integrated sensing of silicon photonic devices with high sensitivity.
Enhancing the performance of 16384QAM based on delta-sigma modulation using geometric shaping in an IMDD system
Authors: Zhao Jianye , Ren Jianxin , Liu Bo , Mao Yaya , Ullah Rahat , Wu Xiangyu , Chen Shuaidong , Wu Yongfeng , Zhao Lilong , Li Zhaohui
Published: August 2023

In this Letter, a new, to the best of our knowledge, geometric shaping method for an ultrahigh-order 16384-ary quadrature amplitude modulation (16384QAM) constellation based on the delta-sigma modulation technique is proposed. Based on the characteristics of delta-sigma modulation, the constellation was optimized to obtain greater constellation gain and improve the maximum performance of the system. Finally, the proposed scheme was demonstrated on an intensity-modulated direct detection (IMDD) system through a 25 km single-mode fiber transmission. On performing experiments, it was found that the suggested approach increases the receiver sensitivity of ultrahigh-order QAM communication systems based on delta-sigma modulation by around 0.5 dB and further enhances the error performance limit.
Photosensitivity and optical nonlinearity in arsenic selenide planar waveguides [Invited]
Authors: Lai Choon Kong , Merklein Moritz , Choi Duk-Yong , Yan Kunlun , Casas Bedoya Alvaro , Madden Stephen J. , Eggleton Benjamin J.
Published: August 2023

We present the first experimental observation of reversible 1550 nm-induced Bragg gratings and stimulated Brillouin scattering (SBS) in a planar waveguide made of high-index chalcogenide material, arsenic triselenide (As2Se3). The temporary grating is inscribed by the two-photon absorption (TPA)-induced refractive index change along the waveguide, facilitated by the high Fresnel reflection from the chip facet. Furthermore, our SBS measurements reveal a Brillouin gain coefficient gB of 7.14 × 10−10 m/W and a frequency shift vB of 7.8 GHz. The Brillouin linewidth ΔvB is measured to be 60 MHz at an input power of 144 mW, which is four times broader compared to As2Se3 fibers. We explain the observed broadening of the linewidth that is attributed to the presence of the photorefractive effect in this platform, which induces a non-uniform refractive index profile along the length of the waveguide. The investigation of photosensitivity and optical nonlinearity in this study holds paramount importance for the realization of reconfigurable nonlinear photonic applications utilizing As2Se3 glasses.
Integrating the rights-based and capability approaches in the analysis of maternal healthcare utilization in sub-Saharan Africa: A multilevel modelling study
Authors: Simona Simona , Likando Nakena , Banda Andrew , Phiri Million
Published: August 2023

The rights-based and capability approaches received increased attention relative to maternal health in the aftermath of the 2015 Millennium Development Goals (MDGs). This may be in view of the sub-optimal progress gained in reducing maternal and child mortality, especially in developing countries. Despite the combined potential of these approaches, there are limited empirical studies testing their viability in aiding our understanding of maternal healthcare utilization in developing countries. This is what this study sought to accomplish. We combined several datasets, including the Demographic Health Surveys (DHS), World Development Indicators, the World Governance Indicators and Freedom House. Bayesian multilevel logistic regression models were applied on three indicators of maternal healthcare utilization (antenatal care visits, institutional delivery, and postnatal check-ups) in relation to selected variables representing right-based and capability approaches. After controlling for relevant individual and community-level factors, the results show that living in countries with high freedom status (POR = 1.19) and higher female secondary school enrolments (POR = 1.54) increases the odds of adequate antenatal care. Residence in countries with high freedom status (POR = 1.33) and higher voice and accountability (POR = 1.72) has a positive influence on institutional delivery. Similar results are reported for postnatal care where country freedom status (POR = 1.89), voice and accountability (POR = 1.25) and female school enrolment (POR = 1.41) are significant predictors. The results imply that the rights-based and capability approaches have the potential to enhance maternal healthcare utilization in sub-Saharan Africa. Therefore, policy strategies emphasizing on freedoms, accountability, and individual capability functionings should be encouraged in the pursuit of partly achieving Sustainable Development Goals (SDG) number 3.
How to eradicate polio in Pakistan: Insights from community health workers
Authors: Sultan Marium A. , Closser Svea , Majidulla Arman , Ahmed Saeed , Naz Farah , Nayyab Sadaf , Zaman Ayesha , Shafique Muhammad , Sohail Ali
Published: August 2023

Pakistan, along with Afghanistan, is one of two countries where wild poliovirus is still endemic. Frontline workers (FLWs) are the staff most intimately familiar with both implementation challenges and community context. Harnessing their expertise may be a way to improve the community-polio program interface, which has been a persistent and shifting challenge in polio-endemic areas of both countries. From 2020–2022, we engaged frontline workers in 18 Super High-Risk Union Councils (SHRUCs) in Pakistan through a Human-Centered Design ideas competition. In that competition, teams of polio FLWs identified the most significant barriers they faced in conducting their work, and suggested solutions to those problems—a window into the issues the program faces by the people who know it best. The suggestions of FLWs on how to eradicate polio fell into four main categories. First, there were suggestions to tackle community fatigue by reducing touchpoints, particularly visits solely for data collection. Second, there were calls to improve Primary Health Care in SHRUCs, as a way of addressing community frustrations over an intense focus on just one disease in the context of numerous acute needs. Third, there were suggested ways to increase community engagement through locally relevant channels. Finally, many workers suggested improvements to Human Resources processes and workplace dynamics. Across these ideas, one repeated concept is the need for balance between the intensity of polio activities required for eradication and the provision of other government services, including health services. FLWs engaged the process deeply, providing well thought out problem statements and ideas for change. It is our view that there is no one more qualified to speak to the issues on the ground than FLWs. There are critical insights available if we listen to people who are instrumental to the success of health programs, but not commonly involved with creating policy.
Does perceived quality mediate the relationship between country of origin image and consumer buying behaviour in Nigerian hypermarkets?
Authors: Martins José Moleiro , Moguluwa Shedrack Chinwuba , Lucas João Luis , Iloka Chiemelie Benneth , Mata Mário Nuno
Published: August 2023

The aim of this study was to examine the relationship between the country of origin image of a product and consumers’ purchasing behavior in Nigerian hypermarkets, as well as the mediating role of perceived price in this relationship. The research considers four aspects of purchasing behavior: information search, product evaluation, purchase decision-making, and post-purchase behavior. A total of 1272 participants completed an online survey, and the data collected was analyzed using structural equation modeling. The results indicated that the country of origin image of a product has a significant and positive impact on consumers’ information search, product evaluation, purchase decision-making, and post-purchase behavior. The study also found that perceived quality does not mediate the impact of country of origin image on information search and product evaluation, but it does play a significant and positive role in purchase decision-making and post-purchase behavior. As a result, it is important for Nigerian hypermarkets to be aware of the origin of the products they import, as importing from countries with a positive image can enhance their performance. Furthermore, perceived quality can mediate purchase and post-purchase decisions.
Problem-solving interventions and depression among adolescents and young adults: A systematic review of the effectiveness of problem-solving interventions in preventing or treating depression
Authors: Metz Kristina , Lewis Jane , Mitchell Jade , Chakraborty Sangita , McLeod Bryce D. , Bjørndal Ludvig , Mildon Robyn , Shlonsky Aron
Published: August 2023

Problem-solving (PS) has been identified as a therapeutic technique found in multiple evidence-based treatments for depression. To further understand for whom and how this intervention works, we undertook a systematic review of the evidence for PS’s effectiveness in preventing and treating depression among adolescents and young adults. We searched electronic databases (PsycINFO,Medline,and Cochrane Library) for studies published between 2000 and 2022. Studies meeting the following criteria were included: (a) the intervention was described by authors as a PS intervention or including PS; (b) the intervention was used to treat or prevent depression; (c) mean or median age between 13–25 years; (d) at least one depression outcome was reported. Risk of bias of included studies was assessed using the Cochrane Risk of Bias 2.0 tool. A narrative synthesis was undertaken given the high level of heterogeneity in study variables. Twenty-five out of 874 studies met inclusion criteria. The interventions studied were heterogeneous in population, intervention, modality, comparison condition, study design, and outcome. Twelve studies focused purely on PS; 13 used PS as part of a more comprehensive intervention. Eleven studies found positive effects in reducing depressive symptoms and two in reducing suicidality. There was little evidence that the intervention impacted PS skills or that PS skills acted as a mediator or moderator of effects on depression. There is mixed evidence about the effectiveness of PS as a prevention and treatment of depression among AYA. Our findings indicate that pure PS interventions to treat clinical depression have the strongest evidence, while pure PS interventions used to prevent or treat sub-clinical depression and PS as part of a more comprehensive intervention show mixed results. Possible explanations for limited effectiveness are discussed, including missing outcome bias, variability in quality, dosage, and fidelity monitoring; small sample sizes and short follow-up periods.