Covalently linked pyrene antennas for optically dense yet aggregation-resistant light-harvesting systems.

In this study we present a novel energy transfer material inspired by natural light-harvesting antenna arrays, zinc(II) phthalocyanine-pyrene (ZnPcPy). The ZnPcPy system facilitates energy transfer from 16 covalently linked pyrene (Py) donor chromophores to the emissive central zinc(II) phthalocyanine (ZnPc) core. Nearly 98% energy transfer efficiency is determined from the changes in emission decay rates between free MePy to covalently linked Py, supported by comparisons of photoluminescence quantum yields using different excitation wavelengths. A comparative analysis of ZnPcPy and an equivalent mixture of ZnPc and MePy demonstrates the superior light-harvesting performance of the covalently linked system, with energy transfer rates 9705 times higher in the covalently bound system. This covalent strategy allows for very high loadings of absorbing Py chromophores to be achieved while also avoiding exciton quenching that would otherwise arise, with the same strategy widely applicable to other pairs of Forster resonance energy transfer (FRET) chromophores.

High Prevalence of Musculoskeletal Disorders Among Dental Professionals: A Study on Ergonomics and Workload in Yemen.

BACKGROUND Dentists frequently have work-related musculoskeletal disorder (MSD) diseases, which are the profession's second most common cause of disability. Awareness of dental ergonomics is necessary for controlling MSDs associated with dental workload. Dental professionals need additional training in dental ergonomics to reduce serious complications associated with dental workload. This questionnaire-based study aimed to evaluate the understanding of physical ergonomics and musculoskeletal disorders in 310 dental health professionals and students in Yemen. MATERIAL AND METHODS This was a cross-sectional study was conducted among 400 dental professionals working in various clinics and universities in Sana'a City, Yemen. They received a self-administered questionnaire that was developed from earlier studies. Five sections made up the questionnaire. The first section of the survey included questions about sex, age, and clinical professions; the second section focused on ergonomic awareness; the third section asked about work conditions; the fourth section asked about the prevalence of musculoskeletal disorders; and the fifth section asked about interventions used. Data were analyzed using SPSS version 25.0, and a P value of ≤0.05 was considered significant. RESULTS Only 310 questionnaires were completed. The participants'; level of understanding of ergonomics was low. One-way ANOVA showed a significant portion of respondents reported having MSDs, and they frequently reported pain related to workload. The neck, lower back, upper back, and shoulders experienced the highest levels of pain. CONCLUSIONS The prevalence of MSDs was high among dental professionals, especially in the lower back, upper back, and shoulder. This necessitates preventive measures like ergonomic positions, ergonomic equipment, regular exercise, and work breaks.

A New Technique to Induce Experimental Myointimal Hyperplasia.

BACKGROUND: Arterial myointimal hyperplasia (MIH) has a significant impact on the long-term outcomes of vascular procedures such as bypass surgery and angioplasty. In this study, we describe a new and innovative technique to induce MIH using a dental flossing cachet in Wistar rats. METHODS: The intimal damage in the common carotid artery was induced by inserting the tip of the dental flossing cachet through the external carotid artery into the common carotid artery and turning it on for 3 rounds of 20 s each (n = 10). After 2 weeks, the rats were anesthetized and the common carotid arteries of the experimental side and the contralateral side (control) were harvested and preserved for histopathological studies. RESULTS: The experimental carotid arteries showed significant intimal proliferation and thickening compared to the controls. The intima/media ratio of the experimental and normal (control) common carotid arteries were 1.274 ± 0.162 and 0.089 ± 0.023 (mean ± SEM), respectively (p < 0.001). CONCLUSION: This technique is simple, inexpensive, and highly reproducible and it induces sufficient MIH to study this phenomenon in animal models.

Transforming Healthcare with AI: Promises, Pitfalls, and Pathways Forward.

This perspective paper provides a comprehensive examination of artificial intelligence (AI) in healthcare, focusing on its transformative impact on clinical practices, decision-making, and physician-patient relationships. By integrating insights from evidence, research, and real-world examples, it offers a balanced analysis of AI's capabilities and limitations, emphasizing its role in streamlining administrative processes, enhancing patient care, and reducing physician burnout while maintaining a human-centric approach in medicine. The research underscores AI's capacity to augment clinical decision-making and improve patient interactions, but it also highlights the variable impact of AI in different healthcare settings. The need for context-specific adaptations and careful integration of AI technologies into existing healthcare workflows is emphasized to maximize benefits and minimize unintended consequences. Significant attention is given to the implications of AI on the roles and competencies of healthcare professionals. The emergence of AI necessitates new skills in data literacy and technology use, prompting a shift in educational curricula towards digital health and AI training. Ethical considerations are a pivotal aspect of the discussion. The paper explores the challenges posed by data privacy concerns, algorithmic biases, and ensuring equitable access to AI-driven healthcare. It advocates for the development of comprehensive ethical frameworks and ongoing research to guide the responsible use of AI in healthcare. Conclusively, the paper advocates for a balanced approach to AI adoption in healthcare, highlighting the importance of ongoing research, strategic implementation, and the synergistic combination of human expertise with AI technologies for optimal patient care.

Cosmetic Surgery and the Diversity of Cultural and Ethnic Perceptions of Facial, Breast, and Gluteal Aesthetics in Women: A Comprehensive Review.

An increasing number of people are opting for cosmetic surgeries. For many years, the physical and aesthetic appearance of Caucasians has been considered to be ideal. However, it is now commonly acknowledged that attractiveness and aesthetic standards vary among cultural backgrounds and ethnic groups and that Western attractiveness criteria no longer apply to all. Herein, we conducted a comprehensive review of studies that examined cultural and ethnic variations in preferences for facial, breast, and gluteal aesthetics, as well as reviewed studies that investigated ethnic disparities in attitudes and motivations for cosmetic surgery. A total of 4532 references were identified, 66 of which met the inclusion criteria. Several studies have reported that facial golden ratios are invalid for representing perceived attractiveness standards among different ethnicities. The majority of studies also indicated that facial aesthetic interventions should not aim to Westernize but to optimize ethnic traits. Significant ethnic differences in preferences for upper- and lower-pole breast proportions have been reported. The size of the buttocks and waist-to-hip ratio were identified as the main factors of buttock aesthetics, with buttock size preferences having a high ethnic diversity. Interest in cosmetic surgical procedures while maintaining ethnic identity continues to grow among young women worldwide. This comprehensive review strongly suggests that accommodating cultural and ethnic differences in aesthetic standards in cosmetic surgery planning can lead to more acceptable cosmetic outcomes.

A custom-made weight-drop impactor to produce consistent spinal cord injury outcomes in a rat model.

Objective: The main objective of this study is to design a custom-made weight-drop impactor device to produce a consistent spinal cord contusion model in rats in order to examine the efficacy of potential therapies for post-traumatic spinal cord injuries (SCIs). Methods: Adult female Sprague-Dawley rats (n = 24, 11 weeks old) were randomly divided equally into two groups: sham and injured. The consistent injury pattern was produced by a 10 g stainless steel rod dropped from a height of 30 mm to cause (0.75 mm) intended displacement to the dorsal surface of spinal cord. The neurological functional outcomes were assessed at different time intervals using the following standardized neurobehavioral tests: Basso, Beattie, and Bresnahan (BBB) scores, BBB open-field locomotion test, Louisville Swim Scale (LSS), and CatWalk gait analysis system. Results: Hind limb functional parameters between the two groups using BBB scores and LSS were significantly different (p < 0.05). There were significant differences (p < 0.05) between the SCI group and the sham group for the hind limb functional parameters using the CatWalk gait analysis. Conclusion: We developed an inexpensive custom-made SCI device that yields a precise adjustment of the height and displacement of the impact relative to the spinal cord surface.

Hyperbilirubinemia and Hyponatremia as Predictors of Complicated Appendicitis.

Several studies have reported elevated serum bilirubin or reduced serum sodium levels in patients with complicated appendicitis (CA). This study examined the efficacy of hyperbilirubinemia, hyponatremia, and both combined in the preoperative diagnosis of CA. Patients who underwent surgery for acute appendicitis were included in this retrospective review. In total, 247 patients were included in the final analysis. Of these, 36 (14.2%) had early appendicitis, 177 (72.0%) had acute suppurative appendicitis, 32 (13.0%) had necrotizing/gangrenous acute appendicitis, and 2 (0.8%) had other types of appendicitis. The mean total bilirubin (TBIL) level was significantly higher in patients with CA than in those with uncomplicated appendicitis. Conversely, the mean serum sodium level was significantly lower in patients with CA than in those with uncomplicated appendicitis. The levels of TBIL (odds ratio: 1.098, 95% CI: 1.052-1.147) and serum sodium (odds ratio: 0.743, 95% CI: 0.646-0.855) were associated with CA. Hyponatremia combined with hyperbilirubinemia yielded significant discriminatory value for the diagnosis of CA. TBIL and serum sodium levels can be considered as adjuvant parameters in the diagnosis of perforated/necrotizing appendicitis. Although hyperbilirubinemia and hyponatremia together were better able to determine the risk of CA than either marker alone, other markers are required to definitively predict CA. Furthermore, large-scale studies are needed to confirm these findings.

Path-length resolved reflectance in tendon and muscle.

Optical diffuse reflectance in fibrous tissues depends on measurement angles in relation to fiber orientation. In this study, path-length resolved optical reflectance was measured in tendon and skeletal muscle samples using a low-coherence Mach-Zehnder interferometer. The results show that the angular dependency in reflectance was eliminated in tendon tissue when representing reflectance as a function of mean path-length. Our analysis indicated that this observation can be understood in the frame work of anisotropic diffuse theory. However the same phenomenon was not observed in muscles, suggesting involvement of additional scattering mechanisms.

Equi-intensity distribution of optical reflectance in a fibrous turbid medium.

Light propagation in a fibrous anisotropic scattering medium is quite different from that in an isotropic medium. Both the anisotropic diffuse equation (ADE) and the continuous time random walk (CTRW) theory predict that the equi-intensity profiles of the surface reflectance have an elliptical shape in a fibrous turbid medium. In this study, we simulated the spatially resolved surface reflectance in a fibrous sample using a Monte Carlo model. A parametric equation was used to quantitatively characterize the geometric profiles of the reflectance patterns. The results indicated that the equi-intensity profiles of surface reflectance had elliptical shapes only when evaluated at distances far away from the incident point. The length ratio of the two orthogonal axes of the ellipse was not affected by the sample optical properties when the ratio of reduced scattering coefficients along the two axes is the same. But the relationship between the aforementioned two ratios was different from the predication of ADE theory. Only for fibers of small sizes did the fitted axes ratios approach the values predicted from the ADE theory.

Effects of Irradiation Parameters and Position on Photobiomodulation Therapy for Spinal Cord Injury Rat Phantom Model: A Dosimetry Simulation Study.

Objective: To optimize photobiomodulation therapy (PBMT) for spinal cord injury (SCI) by studying the effect(s) of irradiation parameters and position of PBMT on injury site using Monte Carlo simulation and a three-dimensional voxelated SCI rat phantom model. Background: Several studies used a range of irradiation parameters and surface irradiances to calculate the fluence delivered to the SCI site. However, most have ignored factors such as the optical properties of tissues, irradiation parameters, and position. Therefore, although such studies present a broad range of treatment outcomes, a comparison of the treatment efficacy concerning the applied fluence using these studies presents certain challenges Methods: In this study, an 810 nm top-hat beam was simulated for 5 numerical apertures (NAs; 0.0, 0.2, 0.4, 0.6, and 0.8), 10 beam radii (0.001, 0.01, 0.1, 0.25, 0.5, 1, 2.5, 5, 10, and 25 mm), and 17 different irradiation positions relative to the SCI site. Results: The beam radius and position strongly affect the accumulated fluence within the injury site, whereas the NA appears to have a smaller effect on the accumulated fluence within the injury site. A large probe beam produces a uniform fluence distribution reaching the injury site, minimizing the effect of misplacing the probe at the center of the injury. Conclusions: Our findings will be beneficial to understanding the effects of irradiation parameters on tissues and organs, which will help reduce variability in the fluence applied to injury sites and will help optimize PBMT outcomes.

The Increasing Role of Artificial Intelligence in Health Care: Will Robots Replace Doctors in the Future?

Artificial intelligence (AI) pertains to the ability of computers or computer-controlled machines to perform activities that demand the cognitive function and performance level of the human brain. The use of AI in medicine and health care is growing rapidly, significantly impacting areas such as medical diagnostics, drug development, treatment personalization, supportive health services, genomics, and public health management. AI offers several advantages; however, its rampant rise in health care also raises concerns regarding legal liability, ethics, and data privacy. Technological singularity (TS) is a hypothetical future point in time when AI will surpass human intelligence. If it occurs, TS in health care would imply the replacement of human medical practitioners with AI-guided robots and peripheral systems. Considering the pace at which technological advances are taking place in the arena of AI, and the pace at which AI is being integrated with health care systems, it is not be unreasonable to believe that TS in health care might occur in the near future and that AI-enabled services will profoundly augment the capabilities of doctors, if not completely replace them. There is a need to understand the associated challenges so that we may better prepare the health care system and society to embrace such a change - if it happens.

Photobiomodulation Optimization for Spinal Cord Injury Rat Phantom Model.

Spinal Cord Injury (SCI) causes interruption along the severed axonal tract(s) resulting in complete or partial loss of sensation and motor function. SCI can cause tetraplegia or paraplegia. Both these conditions can have lifelong excessive medical costs, as well as can reduce life expectancy. Preclinical research showed that Photobiomodulation therapy (PBMT), also known as Low-level laser (light) therapy (LLLT), possesses reparative and regenerative capabilities that have the potential to be used as a complimentary or supplementary SCI therapy. Despite the promising effects of PBMT, there are still no standardized irradiation parameters (i.e. different wavelengths, power, fluence, irradiance, beam type, beam diameters, and irradiation time) and there is also a lack of standardized experimental protocol(s), which makes it difficult to compare different studies. It is, nonetheless, essential to standardize such irradiation parameters in order to provide better PBMTs. The aim of this study, therefore, is to evaluate the delivery of light in a 3D voxelated SCI rat model for PBMT using different irradiation parameters (wavelengths: 660, 810, and 980 nm; beam types: Gaussian and Flat beam; and beam diameters: 0.04-1.2 cm) using Monte Carlo simulation. This study also aids in providing standardization for preclinical research for PBMT, which will eventually translate into clinical standardization upon clinical research studies and results.

Neurophysiological Effects of Aging: A P200 ERP Study.

Age-related effects were studied in 14 younger (M = 34 years) and 14 (M = 47 years) older healthy participants. Event-related potential (ERP) recording was done using a 256-channel EEG system. Results indicated that ERP is affected by advanced age. There was a significant difference in P200 mean latency between the younger participants and older participants for the target (low-probability) stimuli, but no such significance was evident for the P200 mean latency during the presentation of the standard (high-probability) stimuli. As for the P200 mean peak amplitude, the results for the target (low-probability) stimuli did show a significant difference between the two age groups, while the results for the standard (high-probability) stimuli did not show any significant difference between the two age groups. The results of this study are explained in light of aging effects on attentional recruitment and frontal lobe intactness.

Sex Differences in Electrophysiology: P200 Event-related Potential Evidence.

We conducted an event-related potential (ERP) study using a 256-channel dense sensor array electroencephalography (EEG) system to examine how, and if the P200 neurophysiological signal is sexually dimorphic. We had two groups of participants: females (n= 15, mean age = 40.6 years old) and males (n = 15, mean age = 39.0 years old). ERPs from all participants were recorded while the participants performed an oddball task. Results showed that males on average had a significantly larger P200 peak amplitude and a significantly shorter P200 latency period. These results indicate that the P200 ERP is affected by sex. Therefore, suggesting that sex differences exist on an electrophysiological level, which may aid in better understanding of sex-biased biological influences, behaviors, neuropsychiatric disorders, and general brain function.

Evaluation of modified Alvarado scoring system and RIPASA scoring system as diagnostic tools of acute appendicitis.

BACKGROUND: Acute appendicitis is the most common surgical condition presented in emergency departments worldwide. Clinical scoring systems, such as the Alvarado and modified Alvarado scoring systems, were developed with the goal of reducing the negative appendectomy rate to 5%-10%. The Raja Isteri Pengiran Anak Saleha Appendicitis (RIPASA) scoring system was established in 2008 specifically for Asian populations. The aim of this study was to compare the modified Alvarado with the RIPASA scoring system in Kuwait population. METHODS: This study included 180 patients who underwent appendectomies and were documented as having "acute appendicitis" or "abdominal pain" in the operating theatre logbook (unit B) from November 2014 to March 2016. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), diagnostic accuracy, predicted negative appendectomy and receiver operating characteristic (ROC) curve of the modified Alvarado and RIPASA scoring systems were derived using SPSS statistical software. RESULTS: A total of 136 patients were included in this study according to our criteria. The cut-off threshold point of the modified Alvarado score was set at 7.0, which yielded a sensitivity of 82.8% and a specificity of 56%. The PPV was 89.3% and the NPV was 42.4%. The cut-off threshold point of the RIPASA score was set at 7.5, which yielded a 94.5% sensitivity and an 88% specificity. The PPV was 97.2% and the NPV was 78.5%. The predicted negative appendectomy rates were 10.7% and 2.2% for the modified Alvarado and RIPASA scoring systems, respectively. The negative appendectomy rate decreased significantly, from 18.4% to 10.7% for the modified Alvarado, and to 2.2% for the RIPASA scoring system, which was a significant difference (P<0.001) for both scoring systems. CONCLUSION: Based on the results of this study, the RIPASA score is a simple scoring system with better sensitivity and specificity than the modified Alvarado scoring system in Asian populations. It consists of 14 clinical parameters that can be obtained from a good patient history, clinical examination and laboratory investigations. The RIPASA scoring system is more accurate and specific than the modified Alvarado scoring system for Kuwait population.

Time-Resolved Laser-Induced Fluorescence Spectroscopy as a Guidance Tool for Laser Lithotripsy of Gallbladder Stones.

BACKGROUND AND OBJECTIVES: Although laser lithotripsy for fragmentation of gallbladder stones has been applied successfully in many clinical situations, this approach has two major limitations: (1) the potential to damage or perforate the bile duct and (2) the efficiency can be affected by the chemical composition of the gallstones. The present study evaluated the use of time-resolved laser-induced fluorescence spectroscopy to classify stone types and distinguish stone from tissue. MATERIALS AND METHODS: Ex vivo time-resolved laser-induced fluorescence analysis (excitation wavelength λex = 400 nm and emission wavelength = 450-700 nm) of 54 gallbladder stones and seven gallbladder tissue samples was conducted. The spectral and temporal parameters were analyzed using linear discrimination analysis (LDA) to differentiate stone from tissue and to classify different stone types using two wavelength regions (λ1 = 510-530 nm and λ2 = 550-570 nm). RESULTS: Examination of 54 gallbladder stones and seven gallbladder tissue samples showed a significant difference in spectral- and temporal-derived parameters. The data were classified using LDA, and the overall accuracy was 94.88%, 84.39%, and 85.79% for both spectral and temporal parameters, only spectral parameters, and only temporal parameters, respectively. CONCLUSIONS: Our findings establish the feasibility of using time-resolved laser-induced fluorescence spectroscopy as a tool to identify gallbladder stone types and as a stone-tissue detection system to improve the effectiveness of laser lithotripsy procedures and reduce the risk of damaging biliary tract tissues.

Transmission of polarized light in skeletal muscle.

Experiments were conducted to study polarized light transmission in fresh bovine skeletal muscle of varying thicknesses. Two-dimensional polarization-sensitive transmission images were acquired and analyzed using a numerical parametric fitting algorithm. The total transmittance intensity and degree-of-polarization were calculated for both central ballistic and surrounding scattering regions. Full Mueller matrix images were derived from the raw polarization images and the polar decomposition algorithm was applied to extract polarization parameters. The results suggest that polarized light propagation through skeletal muscle is affected by strong birefringence, diattenuation, multiple scattering induced depolarization and the sarcomere diffraction effect.