bluuebunny/crossref_metadata_2025 huggingface dataset:
Early-stage mapping of macromolecular content in APPNL-F mouse model of Alzheimer’s disease using nuclear Overhauser effect MRI
Authors: Swain Anshuman , Soni Narayan D. , Wilson Neil , Juul Halvor , Benyard Blake , Haris Mohammad , Kumar Dushyant , Nanga Ravi Prakash Reddy , Detre John , Lee Virginia M. , Reddy Ravinder
Published: October 2023

Non-invasive methods of detecting early-stage Alzheimer’s disease (AD) can provide valuable insight into disease pathology, improving the diagnosis and treatment of AD. Nuclear Overhauser enhancement (NOE) MRI is a technique that provides image contrast sensitive to lipid and protein content in the brain. These macromolecules have been shown to be altered in Alzheimer’s pathology, with early disruptions in cell membrane integrity and signaling pathways leading to the buildup of amyloid-beta plaques and neurofibrillary tangles. We used template-based analyzes of NOE MRI data and the characteristic Z-spectrum, with parameters optimized for increase specificity to NOE, to detect changes in lipids and proteins in an AD mouse model that recapitulates features of human AD. We find changes in NOE contrast in the hippocampus, hypothalamus, entorhinal cortex, and fimbria, with these changes likely attributed to disruptions in the phospholipid bilayer of cell membranes in both gray and white matter regions. This study suggests that NOE MRI may be a useful tool for monitoring early-stage changes in lipid-mediated metabolism in AD and other disorders with high spatial resolution.
Synaptic and intrinsic plasticity within overlapping lateral amygdala ensembles following fear conditioning
Authors: Sehgal Megha , Ehlers Vanessa E. , Moyer James R.
Published: October 2023

Introduction

New learning results in modulation of intrinsic plasticity in the underlying brain regions. Such changes in intrinsic plasticity can influence allocation and encoding of future memories such that new memories encoded during the period of enhanced excitability are linked to the original memory. The temporal window during which the two memories interact depends upon the time course of intrinsic plasticity following new learning.

Methods

Using the well-characterized lateral amygdala-dependent auditory fear conditioning as a behavioral paradigm, we investigated the time course of changes in intrinsic excitability within lateral amygdala neurons.

Results

We found transient changes in the intrinsic excitability of amygdala neurons. Neuronal excitability was increased immediately following fear conditioning and persisted for up to 4 days post-learning but was back to naïve levels 10 days following fear conditioning. We also determined the relationship between learning-induced intrinsic and synaptic plasticity. Synaptic plasticity following fear conditioning was evident for up to 24 h but not 4 days later. Importantly, we demonstrated that the enhanced neuronal intrinsic excitability was evident in many of the same neurons that had undergone synaptic plasticity immediately following fear conditioning. Interestingly, such a correlation between synaptic and intrinsic plasticity following fear conditioning was no longer present 24 h post-learning.

Discussion

These data demonstrate that intrinsic and synaptic changes following fear conditioning are transient and co-localized to the same neurons. Since intrinsic plasticity following fear conditioning is an important determinant for the allocation and consolidation of future amygdala-dependent memories, these findings establish a time course during which fear memories may influence each other.
Cochlear implantation in unilateral hearing loss: impact of short- to medium-term auditory deprivation
Authors: Ullah Mohammed N. , Cevallos Ashley , Shen Sarek , Carver Courtney , Dunham Rachel , Marsiglia Dawn , Yeagle Jennifer , Della Santina Charles C. , Bowditch Steve , Sun Daniel Q.
Published: October 2023

Introduction

Single sided deafness (SSD) results in profound cortical reorganization that presents clinically with a significant impact on sound localization and speech comprehension. Cochlear implantation (CI) has been approved for two manufacturers’ devices in the United States to restore bilateral function in SSD patients with up to 10 years of auditory deprivation. However, there is great variability in auditory performance and it remains unclear how auditory deprivation affects CI benefits within this 10-year window. This prospective study explores how measured auditory performance relates to real-world experience and device use in a cohort of SSD-CI subjects who have between 0 and 10 years of auditory deprivation.

Methods

Subjects were assessed before implantation and 3-, 6-, and 12-months post-CI activation via Consonant-Nucleus-Consonant (CNC) word recognition and Arizona Biomedical Institute (AzBio) sentence recognition in varying spatial speech and noise presentations that simulate head shadow, squelch, and summation effects (S0N0, SSSDNNH, SNHNSSD; 0 = front, SSD = impacted ear, NH = normal hearing ear). Patient-centered assessments were performed using Tinnitus Handicap Inventory (THI), Spatial Hearing Questionnaire (SHQ), and Health Utility Index Mark 3 (HUI3). Device use data was acquired from manufacturer software. Further subgroup analysis was performed on data stratified by <5 years and 5–10 years duration of deafness.

Results

In the SSD ear, median (IQR) CNC word scores pre-implant and at 3-, 6-, and 12-months post-implant were 0% (0–0%), 24% (8–44%), 28% (4–44%), and 18% (7–33%), respectively. At 6 months post-activation, AzBio scores in S0N0 and SSSDNNH configurations (n = 25) demonstrated statistically significant increases in performance by 5% (p = 0.03) and 20% (p = 0.005), respectively. The median HUI3 score was 0.56 pre-implant, lower than scores for common conditions such as anxiety (0.68) and diabetes (0.77), and comparable to stroke (0.58). Scores improved to 0.83 (0.71–0.91) by 3  months post-activation. These audiologic and subjective benefits were observed even in patients with longer durations of deafness.

Discussion

By merging CI-associated changes in objective and patient-centered measures of auditory function, our findings implicate central mechanisms of auditory compensation and adaptation critical in auditory performance after SSD-CI and quantify the extent to which they affect the real-world experience reported by individuals.
Selpercatinib and capmatinib combination promotes sustained complete response in novel ISOC1-RET fusion lung cancer after resistance to RET inhibitor via MET amplification: Case Report
Authors: Leite Caio Abner , Carvalho Raíssa Pierri , da Costa Felipe Marques , Medeiros Augusto Kreling , Schutz Fabio Augusto , William William Nassib
Published: October 2023

RET fusions occur in 1–2% of non-small cell lung cancer. Selpercatinib and pralsetinib are selective RET inhibitors with significant improvement of outcome in patients with tumor harboring RET fusion; however, resistance mechanisms appear frequently, mainly driven by MAPK pathway bypass, secondary RET mutations, or in 5% via MET amplification. Co-inhibition of RET and MET is a compelling strategy for overcoming MET-dependent resistance to RET inhibitors and potentially other inhibitors. To our knowledge, this is the first report of a novel ISOC1-RET fusion lung cancer with a durable complete response to selpercatinib, with resistance via MET amplification, which was overcome by the successful combination of selpercatinib and capmatinib.
Peripheral vascular access as exclusive access mode in pediatric intensive care unit
Authors: Armstrong Sonya Hayes , Gangu Shantaveer , West Alina Nico , Spentzas Thomas
Published: October 2023

Introduction

The type of vascular access (central or peripheral) in pediatric critical care depends on several factors, including the duration of treatment, the properties of the medication (osmolarity or vesicant), and the need for central pressure monitoring. The utilization of peripheral intravascular catheters (PIVCs) has shown a notable increase in the number of patients being treated. Extended dwell or midline catheters are another peripheral access option in addition to PIVCs. However, there are currently no established guidelines on their placement.

Objectives

The aim of this study is to estimate the duration of dwell time for PIVCs, analyze the specific parameters affecting it, and develop recommendations for switching to extended dwell and midline catheter placement as an alternative to peripheral access.

Methods

The study enrolled patients aged 0–18 years admitted to the pediatric intensive care unit (PICU) for over 24 h and managed with peripheral access only over 2 years (2019–2021).

Measurements and main results

A total of 484 patients met the specified criteria. Patients who had peripheral access exhibited a lower PRISM score and a shorter length of stay in the PICU, with mean values of 18 (SD: 8.5) and 9.5 (SD: 6.4) days, respectively, compared with patients who had central access with mean values of 8.9 (SD: 5.9) and 5.7 (SD: 3.6) days, respectively. The PIVC dwell time was found to be 50.1 h (SD: 65.3) and required an average of 1.6 insertion attempts. Patients with three or more insertions exhibited an increased odds ratio of 5.2 (95% CI: 3.1–8.5) for receiving an extended dwell or midline insertion. Increased dwell time was associated with female gender, 59.5 h (P < 0.001), first attempt insertion, 53.5 h (P < 0.001), use of 24 Ga bore, 56.3 h (P = 0.04), left-sided insertions, 54.9 (P = 0.07), less agitation, 54.8 h (P = 0.02), and less edema, 61.6 (P < 0.001). Decreased dwell time was associated with the use of vancomycin infusion at 24.2 h (P < 0.001) and blood transfusions at 29.3 h (P < 0.001).

Conclusions

Extended catheters last longer than PIVCs in PICU patients. Extended catheter placement requires consideration of the length of treatment, as well as the overall body edema, the level of the patient's restlessness, and the need for vancomycin infusion or blood transfusions, as these factors reduce PIVC dwell time and expose the patients to painful insertions. For such cases, an extended dwell catheter may be a better option, even if the projected treatment time is less than 6 days.
The efficacy of statins for improving cognitive impairments in pediatric patients with neurofibromatosis type 1 (NF-1): a meta-analysis
Authors: Gan Lutong , Zhu Weiwen , Fu Pengqing
Published: October 2023

Background

Given the considerable discrepancies in the evidence concerning the efficacy of statins in ameliorating cognitive impairments in pediatric patients with Neurofibromatosis Type 1 (NF-1), this study conducts a systematic review and meta-analysis to consolidate existing evidence to evaluate the efficacy of statins on cognitive impairments in children with NF-1.

Methods

This study adhered to the PRISMA statement, and the research protocol was pre-registered on PROSPERO (#CRD: 42022369072). Comprehensive searches of databases including PubMed, Embase, and the Cochrane Library were performed up to March 31, 2023 to identify randomized controlled trials (RCTs) investigating the effects of statins on cognitive impairments in children with NF-1. Statistical analyses were conducted using Review Manager 5.4.1. A fixed- or random-effects model was employed according to the I2 statistic. As all data were continuous, MD [95% CI] was used as the pooled estimate.

Results

The final analysis included five RCTs with a total of 364 patients. The meta-analysis indicated that aside from a statistically significant improvement in internalizing problems (MD [95%CI] = 3.61[0.11, 7.10], p = 0.04), Object assembly Test (MD [95%CI] = 0.53[0.12, 0.93], p = 0.01), Cancellation Test (MD [95%CI] = 3.61[0.11, 7.10], p < 0.0001), statins did not exhibit significant efficacy in improving other cognitive aspects in children with NF-1 (p > 0.05). An additional descriptive analysis on indices that cannot be meta-analyzed revealed considerable inconsistency in the therapeutic effect of statins across different studies.

Conclusion

Current evidence suggests that statins may not be effective for cognitive performance in children with NF-1.
Modulation of the hippo-YAP pathway by cyclic stretch in rat type 2 alveolar epithelial cells—a proof-of-concept study
Authors: Ran Xi , Müller Sabine , Brunssen Coy , Huhle Robert , Scharffenberg Martin , Schnabel Christian , Koch Thea , Gama de Abreu Marcelo , Morawietz Henning , Ferreira Jorge M. C. , Wittenstein Jakob
Published: October 2023

Background: Mechanical ventilation (MV) is a life supporting therapy but may also cause lung damage. This phenomenon is known as ventilator-induced lung injury (VILI). A potential pathomechanisms of ventilator-induced lung injury may be the stretch-induced production and release of cytokines and pro-inflammatory molecules from the alveolar epithelium. Yes-associated protein (YAP) might be regulated by mechanical forces and involved in the inflammation cascade. However, its role in stretch-induced damage of alveolar cells remains poorly understood. In this study, we explored the role of YAP in the response of alveolar epithelial type II cells (AEC II) to elevated cyclic stretch in vitro. We hypothesize that Yes-associated protein activates its downstream targets and regulates the interleukin-6 (IL-6) expression in response to 30% cyclic stretch in AEC II.

Methods: The rat lung L2 cell line was exposed to 30% cyclic equibiaxial stretch for 1 or 4 h. Non-stretched conditions served as controls. The cytoskeleton remodeling and cell junction integrity were evaluated by F-actin and Pan-cadherin immunofluorescence, respectively. The gene expression and protein levels of IL-6, Yes-associated protein, Cysteine-rich angiogenic inducer 61 (Cyr61/CCN1), and connective tissue growth factor (CTGF/CCN2) were studied by real-time polymerase chain reaction (RT-qPCR) and Western blot, respectively. Verteporfin (VP) was used to inhibit Yes-associated protein activation. The effects of 30% cyclic stretch were assessed by two-way ANOVA. Statistical significance as accepted at p < 0.05.

Results: Cyclic stretch of 30% induced YAP nuclear accumulation, activated the transcription of Yes-associated protein downstream targets Cyr61/CCN1 and CTGF/CCN2 and elevated IL-6 expression in AEC II after 1 hour, compared to static control. VP (2 µM) inhibited Yes-associated protein activation in response to 30% cyclic stretch and reduced IL-6 protein levels.

Conclusion: In rat lung L2 AEC II, 30% cyclic stretch activated YAP, and its downstream targets Cyr61/CCN1 and CTGF/CCN2 and proinflammatory IL-6 expression. Target activation was blocked by a Yes-associated protein inhibitor. This novel YAP-dependent pathway could be involved in stretch-induced damage of alveolar cells.
Effects of brain–Computer interface combined with mindfulness therapy on rehabilitation of hemiplegic patients with stroke: a randomized controlled trial
Authors: Wang Pei , Liu Jinyu , Wang Lili , Ma Huifang , Mei Xingyan , Zhang Aihua
Published: October 2023

Aim

To explore the effects of brain–computer interface training combined with mindfulness therapy on Hemiplegic Patients with Stroke.

Background

The prevention and treatment of stroke still faces great challenges. Maximizing the improvement of patients’ ability to perform activities of daily living, limb motor function, and reducing anxiety, depression, and other social and psychological problems to improve patients’ overall quality of life is the focus and difficulty of clinical rehabilitation work.

Methods

Patients were recruited from December 2021 to November 2022, and assigned to either the intervention or control group following a simple randomization procedure (computer-generated random numbers). Both groups received conventional rehabilitation treatment, while patients in the intervention group additionally received brain–computer interface training and mindfulness therapy. The continuous treatment duration was 5 days per week for 8 weeks. Limb motor function, activities of daily living, mindfulness attention awareness level, sleep quality, and quality of life of the patients were measured (in T0, T1, and T2). Generalized estimated equation (GEE) were used to evaluate the effects. The trial was registered with the Chinese Clinical Trial Registry (ChiCTR2300070382).

Results

A total of 128 participants were randomized and 64 each were assigned to the intervention and control groups (of these, eight patients were lost to follow-up). At 6 months, compared with the control group, intervention group showed statistically significant improvements in limb motor function, mindful attention awareness, activities of daily living, sleep quality, and quality of life.

Conclusion

Brain–computer interface combined with mindfulness therapy training can improve limb motor function, activities of daily living, mindful attention awareness, sleep quality, and quality of life in hemiplegic patients with stroke.

Impact

This study provides valuable insights into post-stroke care. It may help improve the effect of rehabilitation nursing to improve the comprehensive ability and quality of life of patients after stroke.

Clinical review registration

https://www.chictr.org.cn/, identifier ChiCTR2300070382.
A DEMATEL-based approach of multi-criteria evaluation for urban fire and emergency facilities
Authors: Nyimbili Penjani Hopkins , Erden Turan , Mwanaumo Erastus Misheng'u
Published: October 2023

With the increasing complexity of rapidly growing urban environments and the interactions of humans and socioeconomic and political systems, the global urgency for applying sustainable risk management planning strategies, comprehensively for urban fire risk reduction activities, becomes increasingly evident in most fire-prone megacities worldwide such as Istanbul. The current research aims to examine the complex interrelationships and levels of influence among the criteria previously determined for optimally selecting new urban infrastructure for fire and emergency services in Istanbul as part of the fire risk mitigation planning efforts applying the multi-criteria decision analysis method of the Decision-Making Trial and Evaluation Laboratory (DEMATEL). Useful insights were generated from the study by constructing an intelligible structural model visually in the form of a digraph involving analysis of causal relationships among criteria and their directional influences, as well as corresponding degrees of strength. The findings reveal that high population density is the most critical criterion followed by the density of hazardous materials criterion in effectively planning new urban facilities for fire and emergency services, thus significantly influencing and impacting all the other criteria, while the distance-to-earthquake risk criterion does not influence any other criteria and consequently is not essential in the planning procedure. The DEMATEL model results were validated in terms of levels of criteria significance using previous studies and shown to be in high correlation. In this regard, these contextual relationships established would contribute toward an integrated fire risk mitigation planning policy formulation in urban environments through the engagement of all decision-makers across various backgrounds and disciplines such as urban and city planners, engineers, emergency and risk managers and administrators, socioeconomic and environmental experts, fire service industry practitioners, and local community leaders.
Does fear of infection affect people’s dental attendance during COVID-19? A Chinese example to examine the association between COVID anxiety and dental anxiety
Authors: Yuan Siyang , Zheng Yuanna , Sun Zhe , Humphris Gerry
Published: October 2023

Introduction

Little is known about the psychological and behavioural effect of COVID-19 pandemic on patients and their reaction to dental visiting. Patients may delay attendance due to fears of contracting the corona virus at the dentist. The study aims to confirm the psychometric properties of the two COVID-19 scales and then use dental patient responses to assess the associations between the COVID-19 Anxiety Scale (CAS), dental anxiety (MDAS) and the clinical care COVID-19 Anxiety (CCAS).

Methods

A cross-sectional study was conducted among 503 patients visiting a polyclinic of a stomatological hospital in East China in 2020. Patients completed a survey consisting of demographical information, dental attendance, COVID-19 Anxiety Scale, Clinical Care COVID-19 Anxiety Scale and Modified Dental Anxiety Scale. Confirmatory factor analysis was conducted to determine the psychometric characteristics. A further structural model was tested with the combined measurement model and a path analysis was calculated.

Results

The sample (n = 503) consisted of more women than men (63% vs. 37%). A fifth of the sample (21%) claimed regular dental attendance and just over a third (35%) reported delaying their dental visit due to the pandemic. Our analysis showed that both CAS and CCAS possessed a unidimensional structure. The MDAS was divided into anticipatory and treatment components as separate latent variables. The anticipatory component (MDAS_A) had some association to CCAS through its expression on treatment dental anxiety (MDAS_T). General anxiety about COVID (CAS) had a direct effect on CCAS. The fit statistics were acceptable [Chi-square = 183.27, df = 68, p < .001; CFI = 0.973; RMSEA = 0.058 (95%CIs: 0.048–0.068)] and the Standardised Root Mean Square Residuals (SRMR) index was 0.041.

Discussion

The Clinical Care COVID-19 Anxiety has shown satisfactory psychometric properties. Both dental anxiety and general anxiety about the pandemic have strong associations to patients’ fear of contracting corona virus when using dental facilities. Our study has practical implications to help healthcare providers better understand how environmental stressors influence patients’ overall concerns on infection risks and appropriate dental treatments during the pandemic.
Individuals experiencing disability and the ableist physical literacy narrative: critical considerations and recommendations for practice
Authors: Pushkarenko Kyle , Howse Elizabeth , Gosse Nicholas
Published: October 2023

Physical literacy (PL) has been readily accepted and integrated globally, including organizations affording services to individuals experiencing disability. Despite its uptake, recent research has illustrated that understandings of PL reflect the normative standards of those who do not experience disability, leading to practices that diminish the unique and embodied capability of others while simultaneously validating ableism. While a shift towards recognizing and valuing the heterogeneity associated with PL has recently occurred, the ableist narrative persists. As a result, the operationalization of PL directly contradicts its conceptualization, fostering a physical activity climate that continues to marginalize individuals experiencing disability. With this in mind, this paper critically unpacks PL, challenging the existing ableist narrative and offering suggestions to heighten the level of inclusivity that underscores PL. Pathways, where physical activity professionals contribute to reproducing ableism, will be discussed.
Is laparoscope surgery feasible for upper gastrointestinal cancer patients with a history of abdominal surgery?
Authors: Li Feng , Zhang Fan , Liu Weixin , Zheng Qingfeng , Zhang Moyan , Wang Zhen , Zhang Xuefeng , Qi Ling , Li Yong
Published: October 2023

Objective

To investigate the feasibility of laparoscopic abdominal mobilization in patients with cancers of the esophagus or gastroesophageal junction who have a history of abdominal surgery.

Methods

A total of 132 patients who underwent resection for cancers of the esophagus or gastroesophageal junction from August 2018 to March 2022 in the Department of Thoracic Surgery, Cancer Hospital, Chinese Academy of Medical Sciences, were selected (66 patients with a history of abdominal surgery (observation group) and 66 patients without a history of abdominal surgery (control group)). All patients were treated with preoperative neoadjuvant therapy, based on the clinical stage. Thoracoscopic and laparoscopic resection was performed under general anesthesia. The intraoperative and postoperative conditions and surgical complications were compared between the two groups.

Results

No significant differences were found in baseline data between the observation group and the control group (p > 0.05). Laparoscopic abdominal mobilization was completed in both groups, and there were no significant differences between the two groups in the total operation time [(272.50 ± 86.45) min vs. (257.55 ± 67.96) min], abdominal mobilization time [(25.03 ± 9.82) min vs. (22.53 ± 3.88) min], blood loss [(119.09 ± 72.17) ml vs. (104.39 ± 43.82) ml], and postoperative time to first flatus [(3.44 ± 0.73) d vs. (3.29 ± 0.60) d] (p > 0.05). The abdominal mobilization time was longer in observation group than that in control group (p = 0.057). After excluding the patients (31/66) with a history of simple appendectomy from the observation group, the abdominal mobilization time was significantly longer in observation group than that in control group [(27.97 ± 12.16) min vs. (22.53 ± 3.88) min] (p < 0.05). There were significantly fewer dissected abdominal lymph nodes in the observation group than in the control group [(18.44 ± 10.87) vs. (23.09 ± 10.95), p < 0.05]. After excluding the patients (15/66) with a history of abdominal tumor surgery from the observation group, there was no significant difference in the number of dissected abdominal lymph nodes between the two groups [(20.62 ± 10.81) vs. (23.09 ± 10.95)] (p > 0.05).In addition, no postoperative complications, such as intestinal obstruction, abdominal infection and bleeding, occurred in either group.

Conclusion

Patients with cancers of the esophagus or gastroesophageal junction who have a history of abdominal surgery are suitable for minimally invasive laparoscopic mobilization.
Atrazine: cytotoxicity, oxidative stress, apoptosis, testicular effects and chemopreventive Interventions
Authors: Abarikwu Sunny O. , Ezim Ogechukwu E. , Ikeji Cynthia N. , Farombi Ebenezer O.
Published: October 2023

Atrazine (ATZ) is an environmental pollutant that interferes with several aspects of mammalian cellular processes including germ cell development, immunological, reproductive and neurological functions. At the level of human exposure, ATZ reduces sperm count and contribute to infertility in men. ATZ also induces morphological changes similar to apoptosis and initiates mitochondria-dependent cell death in several experimental models. When in vitro experimental models are exposed to ATZ, they are faced with increased levels of reactive oxygen species (ROS), cytotoxicity and decreased growth rate at dosages that may vary with cell types. This results in differing cytotoxic responses that are influenced by the nature of target cells, assay types and concentrations of ATZ. However, oxidative stress could play salient role in the observed cellular and genetic toxicity and apoptosis-like effects which could be abrogated by antioxidant vitamins and flavonoids, including vitamin E, quercetin, kolaviron, myricetin and bioactive extractives with antioxidant effects. This review focuses on the differential responses of cell types to ATZ toxicity, testicular effects of ATZ in both in vitro and in vivo models and chemopreventive strategies, so as to highlight the current state of the art on the toxicological outcomes of ATZ exposure in several experimental model systems.
Evaluation of sperm counting accuracy on computer-assisted sperm analysis with GoldCyto® slides and glass slides
Authors: Akal Eser
Published: October 2023

Worldwide, various counting chambers and computer-assisted sperm analysis (CASA) devices are in use. The semen’s concentration can vary depending on the depth of the counting chamber and how it is loaded. The study’s objectives were to analyze the effects of various counting chambers on semen concentration results using a GoldCyto® slide and a glass slide in the CASA system and to ascertain the precision of concentration measurements made using glass slides on CASA. The study’s control group was composed of samples with known concentrations (72–80 million sperm/mL) as determined by a spectrophotometer. A total of 21 frozen straws from the same bull of the same date were thawed at 37°C for 30 s and loaded into two different sperm-counting chambers (GoldCyto® slide and glass slide). The sample semen placed in the sperm counting chambers was 5 μL and the same value was entered in the CASA software as 5 μL. Measurements were done and evaluated in 5 different areas. According to the data we obtained, using the glass slide were statistically lower than the spectrophotometer (p < 0.001). GoldCyto® slide results were consistent with spectrophotometer results. Consequently, measurements with GoldCyto® slides in the CASA had consistent results, while measurements with glass slides were inconsistent. It was concluded that GoldCyto® slides are more suitable than glass slides in the concentration examinations of semen. Therefore, more study is needed to optimize the use of glass slides.
Synthesis of a Bistable Recuperative Pump Powered by Shape Memory Alloys and a Two-Section Involute Cam
Authors: Kostov Mihail , Todorov Todor , Mitrev Rosen , Todorov Georgi , Kamberov Konstantin
Published: October 2023

The paper discusses the synthesis problem of a bistable piston pump, employing a driving mechanism that comprises shape memory alloy wires, a two-section involute cam, and an energy-recuperating spring. The transition from one stable end position to another in the pump is achieved by heating and subsequently shortening one of the shape memory alloy wires, initiating the motion of the mechanism. This is then followed by the engagement of the recuperative spring to traverse the intermediate unstable equilibrium position and complete the entire stroke. The reversal of motion follows a similar approach, where the second SMA wire shortens while the first wire remains in a cold state. Importantly, the mechanism necessitates a low force within the shape memory alloy wire to initiate motion towards the opposite stable position. This research encompasses the examination of type, geometric, and force synthesis considerations for the pump, leading to the development of fundamental kinematic and force relationships. Moreover, a novel mechanism is proposed and synthesized, incorporating a two-section involute cam with a cusp point, to generate the desired discontinuous moment function produced by the recuperative spring. Further analysis reveals that the thermal time constant, which regulates the dynamic response of the mechanism, is directly proportional to the diameter of the driving SMA and inversely proportional to the square root of the number of SMA branches.
Study on Ground Experimental Method of Stagnation Point Large Heat Flux of Typical Sharp Wedge Leading Edge Structure
Authors: Wang Ri , Lou Fengfei , Qi Bin , A Rong , Zhou Yuanye , Dong Sujun
Published: October 2023

In this paper, aimed at the problem of large temperature gradient thermal testing with the typical sharp wedge leading edge structure of a hypersonic vehicle, a subsonic high-temperature combustion gas heating (SHCH) test device is used to conduct a series of experiments on the heat flux simulation ability of subsonic high-temperature combustion gas in the stagnation point region. Firstly, for a hypersonic vehicle with a flying height of 24 km and Mach number range of 4~6.5, the stagnation point heat flux in the head area is obtained by numerical calculation of a typical leading edge structure, which is used as the experimental target of the thermal structure test. Secondly, an experimental specimen with a Gardon heat flux meter is designed with the same shape and size as the specimen in the numerical simulations to prepare for the subsequent SHCH test. Thirdly, a method to determine the combustion gas temperature based on a Kriging surrogate model is proposed. CFD numerical simulation is conducted using the SHCH test model, and the numerical calculation results are used as the training dataset. The Kriging surrogate model is used to establish an approximate fitting relationship between the stagnation point heat flux and experimental parameters under SHCH conditions. The corresponding combustion gas temperature values are found, respectively, with the hypersonic aerodynamic heat flux at Mach 5.0~5.4 as the target value. Finally, stagnation point heat flux testing of low-speed and high-temperature combustion gas is performed at different combustion gas temperatures. The experimental and target values obtained from hypersonic aerodynamic thermal simulations are compared and analyzed to verify the heating capacity of SHCH and the feasibility of hypersonic aerothermal simulation testing.
Microstructure Image-Based Finite Element Methodology to Design Abradable Coatings for Aero Engines
Authors: Azmeera Anitha Kumari , Jadhav Prakash , Lande Chhaya
Published: October 2023

Upgrading abradable or wearable coatings in the high-temperature zone of aero engines is advised to increase the efficiency and high-density power in gas turbine engines for military or commercial fixed-wing and rotary-wing aircraft. The development of these coated materials is also motivated by minimization of the number of failures in the blade, as well as increasing their resistance to wear and erosion. It is suggested that abradable coatings or seals be used to accomplish this goal. The space between the rotor and the shroud is minimized thanks to an abradable seal at the blade’s tip. Coatings that can withstand abrasion are often multiphase materials sprayed through thermal spray methods, and which consist of a metal matAzmeerix, oxide particles, and void space. The maintenance of an ideal blend of qualities, such as erosion resistance and hardness, during production determines a seal’s effectiveness. The objective of this research is to develop microstructure-based modelling methodology which will mimic the coating wear process and subsequently help in designing the abradable coating composition. Microstructure modelling, meshing, and wear analysis using many tools such as Fusion360, Hyper Mesh, and LS-Dyna, have been employed to develop an abradable coating model and perform wear analysis using a simulated rub rig test. The relation between percentage composition and morphology variations of metal, oxide, and voids to the output parameters such as hardness, abradability, and other mechanical properties is explored using simulated finite analysis models of real micrographic images of abradable coatings.
LCF Lifetime Reliability Prediction of Turbine Blisks Using Marine Predators Algorithm-Based Kriging Method
Authors: Feng Gaiya , Wen Jiongran , Fei Chengwei
Published: October 2023

To achieve the low-cycle fatigue (LCF) lifetime prediction and reliability estimation of turbine blisks, a Marine Predators Algorithm (MPA)-based Kriging (MPA-Kriging) method is developed by introducing the MPA into the Kriging model. To obtain the optimum hyperparameters of the Kriging surrogate model, the developed MPA-Kriging method replaces the gradient descent method with MPA and improves the modeling accuracy of Kriging modeling and simulation precision in reliability analysis. With respect to the MPA-Kriging model, the Kriging model is structured by matching the relation between the LCF lifetime and the relevant parameters to implement the reliability-based LCF lifetime prediction of an aeroengine high-pressure turbine blisk by considering the effect of fluid–thermal–structural interaction. According to the forecast, when the allowable value of LCF lifetime is 2957 cycles, allowing for engineering experience, the turbine degree of reliability is 0.9979. Through the comparison of methods, the proposed MPA-Kriging method is demonstrated to have high precision and efficiency in modeling and simulation for LCF lifetime reliability prediction of turbine blisks, which, in addition to the turbine blisk, provides a promising method for reliability evaluation of complicated structures. The work done in this study aims to expand and refine mechanical reliability theory.
Formation, Diffusion and Simulation of Green Production Socialized Service Network for Smallholder Farmers Based on SEIRS Model
Authors: Zhou Sishu , Chen Hong
Published: October 2023

(1) Background: The spread of agricultural green production technologies and systems among small farmers is affected by multiple factors such as subjectivity and objectivity. (2) Methods: Based on the marketability of agricultural green production socialization services (AGPSSs), this paper constructs a SEIRS model of infectious disease dynamics, taking the AGPSS of “MAP Sinochem Modern Agriculture” in Tianshan Town, Arhorchin Banner as an example. (3) Results: This study uses Python to simulate the process of forming a network of AGPSS for small farmers and analyzes the law of information dissemination among farmers. (4) Conclusions: This paper explores how multiple factors such as service quality, external environment, farmers’ willingness to decide, government guidance and the responsibility of service subjects play roles in the formation and diffusion of an AGPSS network so as to improve the quality and level of AGPSS provided by enterprises.
Optical Methods for the Detection of Plant Pathogens and Diseases (Review)
Authors: Gudkov Sergey V. , Matveeva Tatiana A. , Sarimov Ruslan M. , Simakin Alexander V. , Stepanova Evgenia V. , Moskovskiy Maksim N. , Dorokhov Alexey S. , Izmailov Andrey Yu.
Published: October 2023

Plant diseases of an infectious nature are the reason for major economic losses in agriculture throughout the world. The early, rapid and non-invasive detection of diseases and pathogens is critical for effective control. Optical diagnostic methods have a high speed of analysis and non-invasiveness. The review provides a general description of such methods and also discusses in more detail methods based on the scattering and absorption of light in the UV, Vis, IR and terahertz ranges, Raman scattering and LiDAR technologies. The application of optical methods to all parts of plants, to a large number of groups of pathogens, under various data collection conditions is considered. The review reveals the diversity and achievements of modern optical methods in detecting infectious plant diseases, their development trends and their future potential.
System of Counting Green Oranges Directly from Trees Using Artificial Intelligence
Authors: Gremes Matheus Felipe , Fermo Igor Rossi , Krummenauer Rafael , Flores Franklin César , Andrade Cid Marcos Gonçalves , Lima Oswaldo Curty da Motta
Published: October 2023

Agriculture is one of the most essential activities for humanity. Systems capable of automatically harvesting a crop using robots or performing a reasonable production estimate can reduce costs and increase production efficiency. With the advancement of computer vision, image processing methods are becoming increasingly viable in solving agricultural problems. Thus, this work aims to count green oranges directly from trees through video footage filmed in line along a row of orange trees on a plantation. For the video image processing flow, a solution was proposed integrating the YOLOv4 network with object-tracking algorithms. In order to compare the performance of the counting algorithm using the YOLOv4 network, an optimal object detector was simulated in which frame-by-frame corrected detections were used in which all oranges in all video frames were detected, and there were no erroneous detections. Being the scientific and technological innovation the possibility of distinguishing the green color of the fruits from the green color of the leaves. The use of YOLOv4 together with object detectors managed to reduce the number of double counting errors and obtained a count close to the actual number of oranges visible in the video. The results were promising, with an mAP50 of 80.16%, mAP50:95 of 53.83%, precision of 0.92, recall of 0.93, F1-score of 0.93, and average IoU of 82.08%. Additionally, the counting algorithm successfully identified and counted 204 oranges, closely approaching the actual count of 208. The study also resulted in a database with an amount of 644 images containing 43,109 orange annotations that can be used in future works.
Achieving Sustainable Agricultural Development through Crop Management and Environmental Harmony
Authors: Zhang Yunbo
Published: October 2023

With the surge in global climate warming and the escalation of extreme weather events, agriculture is facing more frequent and intense challenges [...]
Influence of Surface Methane on Tropospheric Ozone Concentrations and Cereal Yield in Asia
Authors: Tatsumi Kenichi
Published: October 2023

Methane (CH4) emanating from terrestrial sources serves as a precursor for the genesis of tropospheric ozone (O3), a pernicious atmospheric contaminant that adversely modulates the physiological mechanisms of agricultural crops. Despite the acknowledged role of CH4 in amplifying O3 concentrations, the extant literature offers limited quantitative evaluations concerning the repercussions of CH4-mediated O3 on cereal yields. Employing the GEOS-Chem atmospheric chemistry model, the present investigation elucidates the ramifications of a 50% diminution in anthropogenic CH4 concentrations on the yield losses of maize, soybean, and wheat across Asia for the fiscal year 2010. The findings unveil pronounced yield detriments attributable to O3-induced phytotoxicity, with the Indo-Gangetic Plain and the North China Plain manifesting the most substantial yield impairments among the crops examined. A halving of anthropogenic CH4 effluents could ameliorate considerable losses in cereal production across these agriculturally pivotal regions. CH4-facilitated O3 exerts a pernicious influence on cereal yields; nevertheless, targeted mitigation of CH4 effluents, particularly in the vicinity of the North China Plain, holds the potential to substantially attenuate O3 contamination, thereby catalyzing an enhancement in regional cereal production.
A Novel Curve Clustering Method for Functional Data: Applications to COVID-19 and Financial Data
Authors: Wei Ting , Wang Bo
Published: October 2023

Functional data analysis has significantly enriched the landscape of existing data analysis methodologies, providing a new framework for comprehending data structures and extracting valuable insights. This paper is dedicated to addressing functional data clustering—a pivotal challenge within functional data analysis. Our contribution to this field manifests through the introduction of innovative clustering methodologies tailored specifically to functional curves. Initially, we present a proximity measure algorithm designed for functional curve clustering. This innovative clustering approach offers the flexibility to redefine measurement points on continuous functions, adapting to either equidistant or nonuniform arrangements, as dictated by the demands of the proximity measure. Central to this method is the “proximity threshold”, a critical parameter that governs the cluster count, and its selection is thoroughly explored. Subsequently, we propose a time-shift clustering algorithm designed for time-series data. This approach identifies historical data segments that share patterns similar to those observed in the present. To evaluate the effectiveness of our methodologies, we conduct comparisons with the classic K-means clustering method and apply them to simulated data, yielding encouraging simulation results. Moving beyond simulation, we apply the proposed proximity measure algorithm to COVID-19 data, yielding notable clustering accuracy. Additionally, the time-shift clustering algorithm is employed to analyse NASDAQ Composite data, successfully revealing underlying economic cycles.
A Coupling System for Prediction of Physiological Parameters in an Immersed Condition
Authors: Wu Zijiang , Yang Ruiliang , Qian Xiaoming , Shi Yunlong , Zou Chi
Published: October 2023

This study’s major aim is to use a coupling system to predict the physiological parameters of a person wearing a life preserver in an immersion condition. The coupling system is made up of a thermal manikin that can simulate the human body’s thermoregulatory response in an immersion environment, coupled to a multi-segment human thermal model. By comparing the results with those of the subjects, the coupled system’s predictions were shown to be accurate. The core temperature, skin temperature, and heat flow density of ten healthy men were all continuously measured while they wore life preservers and were exposed to the same temperature of air and water. The coupling system demonstrated accurate predictions of heat production and core temperature compared to real measures, with RMSD of 18.91 W and 0.12 °C, respectively. The majority of the predicted values for mean skin temperature were within SD of the measured values, and the paired sample t-test with a significance level of 0.05 showed good agreement with a maximum temperature difference of 1 °C. Also, the coupling system predicted results and the measured results showed some good accuracy for predicting local skin temperatures.
A Robust Design Method for Ultra-Low-Frequency Oscillation Suppression Control in Hydro–Photovoltaic Complementary Systems
Authors: Zeng Xueyang , Chen Gang , Shi Huabo , Wang Sijia , Shi Peng
Published: October 2023

Aiming at the problem of ultra-low-frequency oscillation (ULFO) in power systems, with an oscillation frequency lower than 0.1 Hz, an oscillation suppression control method is proposed. Firstly, the mathematical modeling of the system is carried out, and a cascade correction control method of the governor of hydropower generators is proposed. Secondly, using the ability of photovoltaic (PV) active power to adjust the system frequency, an additional controller for PV active power is proposed. Then, a unified frequency model considering the two controllers is established for multi-hydro and multi-PV systems, and the structural singular value method is used to coordinate the design of the parameters of the hydropower and PV generator controllers to achieve robust performance. Finally, based on a time-domain simulation of single-hydro and single-PV systems and an actual demonstration system located in Sichuan Province, China, the results show that the control method proposed in this paper has a good suppression effect on ultra-low-frequency oscillation under different working conditions, and meets the requirements of robust performance.
Reverse Engineering Used to Profile a Gerotor Pump Rotor
Authors: Baroiu Nicușor , Teodor Virgil Gabriel , Păunoiu Viorel , Moroșanu Georgiana-Alexandra , Dumitrescu Ionaș-Cătălin
Published: October 2023

In most situations, for the proper design of a gerotor pump, numerous parameters must be taken into account: the pump geometry, the properties of the materials from which the pumps are made (Young’s modulus, Poisson’s coefficient, friction coefficients, etc.), the hydraulic characteristics of the circulated fluids (fluid density, kinematic viscosity, etc.), the working performance of the pump (speed ranges, pressure, flow rate, etc.), with greater or lesser influence on volumetric efficiency, work capacity, or energy consumption. The paper presents a study regarding the inspection of the reciprocally enwrapping surfaces of the gerotor pumps using a three-dimensional measurement technique specific to reverse engineering, which involves 3D scanning of the pump components in gearing movement. The components were measured by means of a specific software (GOM Inspect) and compared, by overlap, with the CAD models made with the help of CATIA software (CATIA V5R21). At the same time, an analytical calculation algorithm was developed for the complementarity of virtual representations. Finally, the advantages of the reverse engineering technique compared to the developed theoretical algorithm and traditional CAD design are presented.