Public human dissection and societal connect of anatomical sciences: A glorious association in the past but ethically forbidden practice at present.

Under the futuristic vision of anatomical sciences, a strong societal connection is mandatory. The anatomical practice experienced robust societal participation through public human dissection from the 16th century onward. With a perspective to explore the intersection of spirituality with anatomy, the present study analyzed this momentous period. From a spiritual perspective, the study also reflects on two relevant but presently uncoupled entities of public human dissection and societal connection through the prism of current regulations. Strong representation from the general public during public human dissection was primarily driven by spiritual proclivity and an endorsement from religious authorities. To regulate large gatherings and maintain academic sanctity, anatomical theaters emerged as dedicated spaces for such a merger. With time and growing financial support, the theaters transformed from temporary structures to elaborate architectural marvels, further propelling already robust societal connections associated with the practice. Nevertheless, a confluence of multiple factors led to the violation of spiritual principles and a consequent decrease in societal participation from the early 18th century, eventually culminating in the demise of such spectacle. Presently, public human dissection-when done-is mostly conducted for commercial gains and in contravention of ethical norms. It is against the essence of spirituality and harbors a bleak prospect for societal connection. Contrastingly, measures adopted to promote societal participation (mostly related to body donation) were quite effective and followed the principles of spirituality. Societal connections served anatomy in the past and can lead to its advancement if approached through a righteous path.

Evolution of staining methods in neuroanatomy: Impetus for emanation of neuron doctrine during the turn of 20th century.

The nervous system is distinctive as compared to other tissue systems in human body owing to intricate structural organization. Histological studies played a key role in unveiling complex details of nervous tissue. However, the process of developing suitable staining method for nerve cells was arduous and spanned across almost half a century. The present study explored details of the journey involving quest for propitious staining method in neuroanatomy culminating in promulgation of neuron doctrine at the onset of 20th century. Initial efforts involving hematoxylin (including its diverse modifications) and subsequent adoption of analogous dye-based stains (like Nissl's method) had limited success in visualization of different parts of a nerve cell and structural details of nervous tissue. This was due to inability of dye-based stains to penetrate the connective tissue sheath of nervous tissue. Eventually, advent of metallic stains in form of silver impregnation method (Golgi stain), reduced silver impregnation method with gold stain (Cajal's stain) and silver carbonate staining method of Río-Hortega unraveled the structure of nervous tissue. The evolution of staining methods catalyzed the refinement of theories pertinent to constitution of nervous tissue. Golgi's staining led to emergence of reticular theory (neurons exist as a network) and Nissl's staining was the basis of the concept of Nervösen Grau (nerve cells and glial cells are embedded in mass of gray matter). Finally, Cajal's staining method successfully elucidated the complex anatomy of nerve terminals and resulted in emanation of neuron doctrine (neurons exists as individual units with adjacent connections).

Exploring the clinical characteristics and prevalence of the annular pancreas: a meta-analysis.

BACKGROUND: The annular pancreas (AP) is a rare gastrointestinal congenital malformation, in which malrotation of the pancreatic ventral bud in the seventh week of embryonic development manifests in a partial or complete ring of tissue around the second part of the duodenum. METHODS: The main online medical databases such as PubMed, ScienceDirect, Wiley online library, Web of Science, and EBSCO discovery service were used to gather all relevant studies on the AP. RESULTS: A total of 12,729,118 patients were analyzed in relation to the prevalence of AP. The pooled prevalence of AP was 0.0045% (95% CI: 0.0021%-0.0077%). The most frequent comorbidity in adults and children was duodenal obstruction, with a pooled prevalence of 24.04% and 52.58%, respectively (95% CI: 6.86%-46.48% and 35.56%-69.31%, respectively). The most frequent operation in adult patients with AP was duodenojejunostomy, with pooled prevalence established at 3.62% (95% CI: 0.00%-10.74%). CONCLUSION: The diagnostic complexity of AP is accentuated by its nonspecific clinical symptoms, making accurate identification reliant on imaging studies. Therefore, having a thorough knowledge of the clinical characteristics of the AP and its associated anomalies becomes paramount when faced with this rare congenital condition.

Energy transfer driven brightening of MoS2 by ultrafast polariton relaxation in microcavity MoS2/hBN/WS2 heterostructures.

Energy transfer is a ubiquitous phenomenon that delivers energy from a blue-shifted emitter to a red-shifted absorber, facilitating wide photonic applications. Two-dimensional (2D) semiconductors provide unique opportunities for exploring novel energy transfer mechanisms in the atomic-scale limit. Herein, we have designed a planar optical microcavity-confined MoS2/hBN/WS2 heterojunction, which realizes the strong coupling among donor exciton, acceptor exciton, and cavity photon mode. This configuration demonstrates an unconventional energy transfer via polariton relaxation, brightening MoS2 with a record-high enhancement factor of ~440, i.e., two-order-of-magnitude higher than the data reported to date. The polariton relaxation features a short characteristic time of ~1.3 ps, resulting from the significantly enhanced intra- and inter-branch exciton-exciton scattering. The polariton relaxation dynamics is associated with Rabi energies in a phase diagram by combining experimental and theoretical results. This study opens a new direction of microcavity 2D semiconductor heterojunctions for high-brightness polaritonic light sources and ultrafast polariton carrier dynamics.

Responsible research in the practice of anatomy: Attributes relevant to body donors and human tissues sourced from them.

Responsible Research involves setting moral examples before fellow academicians and the society as a whole. The concept of Responsible Research applies appropriately to ethical sourcing and handling of human tissues. The present study was undertaken to analyze present situation regarding implementation of attributes of Relevant Research in relation to body donors in anatomical research. A literature search of relevant, peer-reviewed, published articles was undertaken from indexed databases (Medline & PubMed, Scopus, Embase, CINAHL Plus, Web of Science and Google Scholar) for this study. The following attributes of Responsible Research were identified for possible intervention: the fact that research was conducted on human tissues from body donors and details regarding ethical handling thereof may be explicitly mentioned in method section; expression of gratitude towards body donors by authors may be included in acknowledgement section; editor's and publisher's note in support of adoption of attributes of Responsible Research may be included in published research. Adherence to best practices in terms of ethical guidelines requires anatomists to embrace a responsible approach in research from an inclusive perspective. Accordingly, practice of acknowledging the body donors may be nurtured and augmented to include the anonymised dead (human tissues from unclaimed bodies and unknown source) provided the research protocol received clearance from authorities concerned with ethical scrutiny. Moreover, adoption of the practice in review articles will enhance the boundaries of Responsible Research in anatomical science. Thus, few recommendations are proposed as epilogue for effectual implementation of the notion floated in present study.

Unraveling the Ultrafast Coherent Dynamics of Exciton Polariton Propagation at Room Temperature.

Exciton polaritons are widely considered as promising platforms for developing room-temperature polaritonic devices, owing to the high-speed propagation and nonlinear interactions. However, it remains challenging to explore the dynamics of exciton polaritons specifically at room temperature, where the lifetime could be as small as a few picoseconds and the prevailing time-averaged measurement cannot give access to the true nature of it. Herein, by using the time-resolved photoluminescence, we have successfully traced the ultrafast coherent dynamics of a moving exciton polariton condensate in a one-dimensional perovskite microcavity. The propagation speed is directly measured to be ∼12.2 ± 0.8 µm/ps. Moreover, we have developed a time-resolved Michelson interferometry to quantify the time-dependent phase coherence, which reveals that the actual coherence time of exciton polaritons could be much longer (nearly 100%) than what was believed before. Our work sheds new light on the ultrafast coherent propagation of exciton polaritons at room temperature.

Manipulating nonlinear exciton polaritons in an atomically-thin semiconductor with artificial potential landscapes.

Exciton polaritons in atomically thin transition-metal dichalcogenide microcavities provide a versatile platform for advancing optoelectronic devices and studying the interacting Bosonic physics at ambient conditions. Rationally engineering the favorable properties of polaritons is critically required for the rapidly growing research. Here, we demonstrate the manipulation of nonlinear polaritons with the lithographically defined potential landscapes in monolayer WS2 microcavities. The discretization of photoluminescence dispersions and spatially confined patterns indicate the deterministic on-site localization of polaritons by the artificial mesa cavities. Varying the trapping sizes, the polariton-reservoir interaction strength is enhanced by about six times through managing the polariton-exciton spatial overlap. Meanwhile, the coherence of trapped polaritons is significantly improved due to the spectral narrowing and tailored in a picosecond range. Therefore, our work not only offers a convenient approach to manipulating the nonlinearity and coherence of polaritons but also opens up possibilities for exploring many-body phenomena and developing novel polaritonic devices based on 2D materials.

The Sun Also Rises: Tracing the evolution of humanistic values in anatomy pedagogy and research, including cadaveric acquisition practices.

Anatomy has always been at the intersection of the socio-cultural and political landscape, where new ideas constantly replace older wisdom. From ancient Egyptians through the Greeks, and then the Romans, finally culminating into the European Renaissance-all the significant eras of human civilisation have left their insignia and distinct marks on the evolution of anatomical practices. Despite its utility as a tool for anatomy pedagogy and research that has proven its worth over millennia, cadaveric dissection has particularly been subject to political and social vicissitudes. A major debate about anatomical dissection lay with the ethical considerations, or its lack thereof, while acquiring corpses for demonstration in the dissection halls. From antiquity, anatomical dissection-often synonymous with medical studies-had typically been carried out on the dead bodies of executed criminals with certain laws, such as the Murder Act of 1752, facilitating such uses. Gradually, the uses of unclaimed bodies, resourced primarily from the impoverished sections of society, were also introduced. However, these body acquisition protocols often missed the crucial element of humanism and ethical considerations, while knowledge augmentation was taken as sufficient reasoning. Unfortunately, a gross disregard towards humanistic values promulgated heinous and illegal practices in acquiring corpses, including grave robbery and even murders like in the case of Burke and Hare murders of 1828. Follow-up legislation, such as the Anatomy Act of 1832, and comparable laws in other European nations were passed to curb the vile. What distils from such a historical discourse on humane values in anatomy dissection, or medical science in general, is that the growth and integration of humanism in anatomy have never been linear, but there were intermittent and, yet, significant disruptions in its timeline. For example, there were serious human rights violations in anatomical practices during the Third Reich in Germany that perpetrated the holocaust. The medical community has kept evolving and introducing new moral values and principles while using such egregious events as lessons, ultimately resulting in the Declaration of Helsinki in 1964. This article revisits the heterogeneous journey of integrating humanistic values in anatomy practice. Such humanistic traits that, like medical science, have also developed over centuries through the inputs of physicians, researchers, and philosophers-from Greece to modernity with an important stopgap at the Renaissance-are a fascinating lore that deserves to be re-envisioned through the lens of contemporary values and ethos. In parallel to human medicine, humanistic values continue to influence veterinary medicine, a welcome development, as our society condemns animal cruelty in any form. There are lessons to be learned from this historical journey of how humanism shaped many of the concepts that anatomists use now. Finally, and most importantly, it might prevent the medical community from repeating the same mistakes by cautioning against the traps that are there, and in a convoluted world where morality as such is eroding from our social fabric, will always be there. Such historical account acts as a righteous, ethical, and contextual compass to guide the existing and upcoming anatomists in discerning between light and dark, right and wrong, and roads-to be or not to be-taken.

Focus on evidence-based anatomy in contemporary anatomy education: Arguments in favor of a pragmatic approach.

The concept of evidence-based anatomy (EBA) emerged in 2014 and has become a significant element in contemporary anatomy education. The evolving fabric of the medical education curriculum has necessitated critical changes in practice. EBA enables these changes to be incorporated seamlessly and implemented congruently into anatomy education programs. However, in parallel, non-evidence-based (classical) knowledge that has been built up through centuries of anatomical practice continues to be the core element of anatomy education in some countries/regions. Its inherent limitations hinder integration with clinical practice, leading to a rise in misadventures in the clinical setting. This viewpoint commentary highlights the strengths of EBA vis-à-vis the related attributes of classical anatomy. Appropriate arguments show that EBA helps to reduce cognitive load and enables knowledge to be delivered through innovative education tools. EBA also helps to create an inclusive learning environment in a technology-driven era. Moreover, empowered by robust resources, it is driving the pertinent amalgamation of anatomy knowledge with clinical practice. This viewpoint article endorses the adoption of EBA in contemporary anatomy education on the basis of its potential for shaping future anatomical practice.

Analysing lumbar pedicle morphometry observed via traditional and recent modalities.

Objective: The present study was conducted to collect morphometric data on the lumbar vertebrae pedicles of the adult population from the eastern parts of India and analyse the variations, if any, with other parts of the country and the world. Methods: The retrospective cross-sectional study where lumbar pedicle morphometric data was obtained via dried bone, the 3D Lumbar vertebrae images were obtained by scanning the dried lumbar vertebrae, and the 3D lumbar vertebrae model was generated from a 1 mm thin CT scan slice of the Lumbar spine of patients who were advised to have a CT scan of the abdomen for reasons other than related to the vertebral column. Both linear and angular measurements in the lumbar pedicles were made bilaterally. Results: The transverse pedicle width is widest at L3 and the narrowest at L2 vertebra bilaterally. The sagittal pedicle width at L4 vertebrae was observed to be the widest bilaterally, while L3 had the narrowest pedicle. The pedicular and body length along the pedicular axis is longer than the central axis at all the lumbar levels. The linear measurement along the pedicular axis was longest at L5 bilaterally via both modes, with a range of 18.2-47.31 mm for bones and 21.03-49.28 mm for CT scan morphometry. The transverse pedicular angle on analysis was observed to increase as one goes down the spine from L1 to L5, with a steep rise between L4 and L5. In contrast, the sagittal pedicular angle decreased as we went caudally toward the L5 vertebrae. Conclusion: The present study data had significant differences among the values reported in the literature from the different populations for the parameters studied. The data obtained by this study will be highly beneficial for the success of the free-hand technique of pedicle screw insertion.

Higher-order topological polariton corner state lasing.

Unlike conventional laser, the topological laser is able to emit coherent light robustly against disorders and defects because of its nontrivial band topology. As a promising platform for low-power consumption, exciton polariton topological lasers require no population inversion, a unique property that can be attributed to the part-light-part-matter bosonic nature and strong nonlinearity of exciton polaritons. Recently, the discovery of higher-order topology has shifted the paradigm of topological physics to topological states at boundaries of boundaries, such as corners. However, such topological corner states have never been realized in the exciton polariton system yet. Here, on the basis of an extended two-dimensional Su-Schrieffer-Heeger lattice model, we experimentally demonstrate the topological corner states of perovskite polaritons and achieved polariton corner state lasing with a low threshold (approximately microjoule per square centimeter) at room temperature. The realization of such polariton corner states also provides a mechanism of polariton localization under topological protection, paving the way toward on-chip active polaritonics using higher-order topology.

Compact spin-valley-locked perovskite emission.

Circularly polarized light sources with free-space directional emission play a key role in chiroptics1, spintronics2, valleytronics3 and asymmetric photocatalysis4. However, conventional approaches fail to simultaneously realize pure circular polarization, high directionality and large emission angles in a compact emitter. Metal-halide perovskite semiconductors are promising light emitters5-8, but the absence of an intrinsic spin-locking mechanism results in poor emission chirality. Further, device integration has undermined the efficiency and directionality of perovskite chiral emitters. Here we realize compact spin-valley-locked perovskite emitting metasurfaces where spin-dependent geometric phases are imparted into bound states in the continuum via Brillouin zone folding, and thus, photons with different spins are selectively addressed to opposite valleys. Employing this approach, chiral purity of 0.91 and emission angle of 41.0° are simultaneously achieved, with a beam divergence angle of 1.6°. With this approach, we envisage the realization of chiral light-emitting diodes, as well as the on-chip generation of entangled photon pairs.

The subscapularis muscle: A meta-analysis of its variations, prevalence, and anatomy.

BACKGROUND: The subscapularis (SSC) is the largest rotator cuff muscle and is involved in the medial rotation, abduction, adduction, and anterior stabilization of the shoulder. It is anatomically variable, as is the morphology and prevalence of the accessory SSC (aSSC), a rare muscle slip attached to the SSC. There is no current review investigating the prevalence and morphometrics of the SSC and aSSC. PURPOSE: To investigate the prevalence of the morphological variants of the SSC and aSSC via meta-analysis and review the relevant literature involving cadaveric, magnetic resonance imaging, and ultrasonographic studies. STUDY DESIGN: Meta-analysis. MATERIALS AND METHODS: Literature data reporting the prevalence rates and morphometrics of the SSC and aSSC and their variants were pooled. Literature searches and data analyses were performed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Anatomical Quality Assurance guidelines. RESULTS: Forty-six studies, totaling 2166 shoulders, were assessed. The SSC showed an overall length, thickness, cross-sectional area, and volume of 152.2 mm (95% confidence interval, CI, 103.8-200.5 mm), 5.6 mm (95% CI, 4.6-6.6 mm), 18.1 cm2 (95% CI, 14.2-22.0 cm2 ), and 126.9 cm3 (95% CI, 87.2-166.5 cm3 ), respectively. The SSC displayed substantial variations in its origin and insertion points and in the composition of its tendon. The aSSC had an overall pooled prevalence of 24.6% (95% CI, 0.0%-76.9%). CONCLUSIONS: The SSC and aSSC have been implicated in multiple shoulder pathologies, including muscle and tendon ruptures and neurovascular compromise. A better understanding of SSC and aSSC variants when diagnosing and treating their related pathologies will reduce patient morbidity and improve treatment regimens.

Johannes Nathanael Lieberkühn (1711-1756): luminary eighteenth century anatomist and his illuminating discovery of intestinal glands.

Johannes Nathanael Lieberkühn was a prodigious anatomist whose meticulous experiments and precise detailing helped in comprehending the microscopic anatomy of digestive system during early part of eighteenth century. Notably, his inventions in the field of microscopy aptly complemented his quest for anatomical knowledge at microscopic level. He designed a reflector (Lieberkühn reflector) which enhanced the amount of focussed light leading to bright illumination of tissue specimen. He invented the solar microscope which provided excellent resolution of minute anatomical details. Lieberkühn discovered the digestive juice secreting tubular glands (glands of Lieberkühn) present at the base of intestinal villi producing epithelial invaginations (crypts of Lieberkühn). He also described the intricate juxtaposition of blood vessels in relation to a single intestinal villi. Moreover, through empirically designed experimental set up, Lieberkühn was able to demonstrate the flow of lymph from intestinal villi to collecting lymphatic vessels. Also, his grandiose collection of laboratory specimens involving vascular anatomy are a testimony of his untiring efforts in academia. His contributions were seminal in comprehending the anatomy of digestive system and paved the way for future revelations. His work unveiled the enormous scope of microanatomy in medical science and catalysed the advent of histological staining methods a century later.

Evolving strategies in whirlwind mode: The changing face of anatomy education during Covid-19 pandemic.

The Covid-19 pandemic stipulated adoption of unfamiliar strategies for delivering anatomy education in online mode. The factors which determine education strategies are variable across geographical regions. It was perceived that an overview of education strategies around the globe would be useful for anatomists. Hence this narrative review was undertaken to collate observations from different geographical regions pertaining to education strategies adopted during the pandemic. Data relevant to the topic of study were extracted from 12 articles that were selected from an initial pool of 317 articles based on search criteria set for the review. Subtle differences in core education strategies implied that baseline response from anatomists was similar across regions. It was evident that online digital tools were key elements of education strategies adopted by educators for delivering online anatomy classes across the globe. Interestingly, a considerable gap in terms of number and variety of online tools used for anatomy education (those requiring commercial purchase) was noted between economically developed and developing regions. This may have an impact on learning outcome for students and may even lead to variations in anatomical knowledge by regions. It was observed that offline human dissection sessions were incorporated into online practical classes in one region as positive cases showed a declining trend. This positive development is worth emulating elsewhere based on cautious assessment of prevailing situation. From a broad perspective timely introduction of education strategies ensured delivery of anatomy education during the pandemic and gave an evolved outlook to the fabric of anatomy education.

The place of ethics in practice of anatomical sciences: have we left our dark past behind and looking towards a bright future?

INTRODUCTION: Anatomical sciences involve handling of human tissues and, therefore, application of principles of bioethics is central to anatomical practice. For a considerable period of time, anatomy was practiced without ethical norms as concept of ethics developed during second half of twentieth century. Hence, possible glimpse into contrast in ethical standards between anatomy in the past and present was deemed as an intriguing research theme. METHODS: A literature search was undertaken from indexed databases (Medline and Pubmed, Scopus, Embase, CINAHL Plus, Web of Science and Google Scholar). Relevant data were extracted from 37 articles that were selected from an initial pool of 752 articles based on search criteria set for the study. RESULTS: Prevalent anatomical practices in the past such as dissection of executed criminals, acts of vivisection, illegal procurement of human remains, use of human tissues obtained as part of war crimes and dissection of human fetuses as well as their archival were analyzed through prism of established ethical norms in present day. The observations from past were presented vis-à-vis ethical practices undertaken in present times such as use of donated bodies and/or body parts procured through legal means for dissection, adherence to ethical norms during dissection, archival of human tissues mandating stringent regulation and dignified disposal of human remains. Existing loop holes were identified and future prospects regarding ethical standards in anatomy were highlighted based on rational judgment of existing trends. CONCLUSION: The article concludes with defense on future prospects of ethics in anatomy based on documented arguments.

Reporting ChAracteristics of cadaver training and sUrgical studies: The CACTUS guidelines.

INTRODUCTION: Recent systematic reviews highlighted increasing use of cadaveric models in the surgical training, but reports on the characteristics of the models and their impact on training are lacking, as well as standardized recommendations on how to ensure the quality of surgical studies. The aim of our survey was to provide an easy guideline that would improve the quality of the studies involving cadavers for surgical training and research. METHODS: After accurate literature review regarding surgical training on cadaveric models, a draft of the CACTUS guidelines involving 10 different items was drawn. Afterwards, the items were improved by questionnaire uploaded and spread to the experts in the field via Google form. The guideline was then reviewed following participants feedback, ergo, items that scored between 7 and 9 on nine-score Likert scale by 70% of respondents, and between 1 and 3 by fewer than 15% of respondents, were included in the proposed guideline, while items that scored between 1 and 3 by 70% of respondents, and between 7 and 9 by 15% or more of respondents were not. The process proceeded with Delphi rounds until the agreement for all items was unanimous. RESULTS: In total, 42 participants agreed to participate and 30 (71.4%) of them completed the Delphi survey. Unanimous agreement was almost always immediate concerning approval and ethical use of cadaver and providing brief outcome statement in terms of satisfaction in the use of the cadaver model through a short questionnaire. Other items were subjected to the minor adjustments. CONCLUSION: 'CACTUS' is a consensus-based guideline in the area of surgical training, simulation and anatomical studies and we believe that it will provide a useful guide to those writing manuscripts involving human cadavers.

Prevalence and clinical relevance of the anatomical variations of suprarenal arteries: a review.

The suprarenal arteries are arising from three sources: superior suprarenal artery, middle suprarenal artery, and inferior suprarenal artery. Variations in the arterial supply of the suprarenal glands in respect to origin and number are quite common and very frequently reported. The most common variation noted is in the inferior suprarenal artery followed by the middle suprarenal artery and the least common variations were observed in the superior suprarenal artery. Arteriogram of the inferior suprarenal artery is crucial in suprarenal tumour diagnosis but variation in the branching pattern and multiplicity of these arteries can cause hindrance in arteriography. The absence of middle suprarenal artery was seen to be associated with increased number of the inferior suprarenal artery. Variation in the multiplicity of arteries was observed more frequently in the inferior suprarenal artery and middle suprarenal artery which was more on the right side in most of the studies. Also, the variation in suprarenal arteries was often correlated to variations in inferior phrenic and gonadal arteries. The variations were observed to be more common on the left side therefore right adrenalectomy should be preferred over the left one. The loop formed by the inferior suprarenal artery around the right renal vein can cause venous obstruction. These variations of suprarenal vasculature are explained on the developmental basis, and prior knowledge of such variants is crucial for nephrologists to ensure minimum blood loss while performing laparoscopic adrenalectomy especially for large adrenal tumours and pheochromocytoma where the duration of surgery exceeds the usual.