bluuebunny/crossref_metadata_2025 huggingface dataset:
Free Flap Monitoring Using Infrared Thermography: An Objective Adjunct to Clinical Monitoring
Authors: Singla Priyanka , Dixit Pawan Kumar , Kala Prakash Chandra , Katrolia Deepti , Karmakar Shilpi , Humnekar Akhilesh , Singh Apoorva Pratap
Published: May 2024

Background Early detection of free flap compromise is critical for salvage of the flap. Various methods of free flap monitoring have been described, but clinical assessment is the standard method for among all. In this study, role of infrared thermography is evaluated for free flap monitoring.

Materials and Methods In patients undergoing free flap surgery, monitoring was done using standard clinical parameters and infrared thermography as per our institutional protocol. Mean temperature difference (∆T) between the flap and the surrounding skin was calculated using the temperature readings from the thermal images intra- and postoperatively. The accuracy of infrared thermography in flap monitoring was assessed in comparison to the standard clinical protocol.

Results Forty-one flaps were included in the analysis, out of which five flaps got compromised. It was observed that the mean temperature difference was higher (mean ∆T 0.20–0.59 vs. 2.38–3.32) when there was a flap compromise, and this temperature difference was evident even before the development of clinical signs. The temperature difference in venous thrombosis (mean ∆T 1.0–2.7) was found to be slightly lower than in arterial insufficiency (mean ∆T 2.1–4.4). For a ∆T cutoff value of 2°C, the thermal camera had a sensitivity of 88.6%, specificity of 98.9%, positive predictive value of 93.9%, and negative predictive value of 97.7%.

Conclusion Infrared thermography is a valuable and noninvasive objective tool in free flap monitoring, which can detect flap compromise (increasing value of ∆T) even before it becomes clinically evident.
Evaluating Diagnostic Algorithms for Heparin-Induced Thrombocytopenia using Two Combined Automated Rapid Immunoassays
Authors: Bissola Anna-Lise , Zhang Yi , Cranstone Madison , Moore Jane C. , Warkentin Theodore E. , Arnold Donald M. , Nazy Ishac
Published: May 2024

Heparin-induced thrombocytopenia (HIT) is an autoimmune disorder caused by antibodies against platelet factor 4 (PF4) and heparin complexes. Rapid immunoassays (IAs) for detection of these antibodies mark a milestone in HIT diagnosis, despite a higher false-positive rate compared with functional platelet-activation assays. However, combining different rapid IAs may help to improve their diagnostic specificity. Here, we compared the individual performance of the latex immunoturbidimetric assay (LIA; HemosIL HIT-Ab [PF4-H]; sensitivity 91.7%, specificity 68.4%) and chemiluminescence immunoassay (CLIA; HemosIL AcuStarHIT-Ab [PF4-H]; sensitivity 92.4%, specificity 85.8%) with their combined performance using two unique diagnostic algorithms in a single prospective cohort of suspected HIT patients. Using the simultaneous algorithm adapted from Warkentin et al, the combined LIA–CLIA had a sensitivity of 99.0% and specificity of 64.3%. The sequential algorithm adapted from Rittener-Ruff et al was applied in two theoretical scenarios to reflect real-world circumstances in diagnostic laboratories where access to clinical information is limited: (1) assuming all patients had an intermediate 4Ts score and (2) assuming all patients had a high 4Ts score. This algorithm correctly predicted HIT in 94.5% (high 4Ts) and 96.0% (intermediate 4Ts) and excluded HIT in 82.6% (high 4Ts) and 80.1% (intermediate 4Ts) of patients in either scenario, respectively. Although both combined algorithms improved diagnostic performance of individual IAs, the simultaneous algorithm showed fewer false predictions (7.9%) than the sequential algorithm (intermediate 4Ts: 37.6% and high 4Ts: 41.5%) and proved more practical as it does not rely on physician evaluations. Our findings highlight the importance of accounting for clinician and interlaboratory variability when evaluating diagnostic tests for HIT.
“They Surge-on…The Journey of an Early Career Plastic Surgeon in India as I see it”
Authors: Bhat Sowrabha
Published: May 2024

The journey to becoming a plastic surgeon is a long one. Most nonsurgeons are unaware of the actual scope of plastic surgery and the spectrum of surgeries done by plastic surgeons. The constant look-out for “cutting chances” from early in the career can be quite exhausting and may take a toll on the professional relationships as well as personal lives of plastic surgeons. Many a time in the wake of striving for operative opportunities, research may take a back seat. Being an endocrinologist, who has witnessed closely, the life of a young lady plastic surgeon I have come to understand that the grind and struggle for development of skills in microsurgical techniques can be overwhelming. To prevent professional burnout, encouragement and guidance from mentors as well as setting priorities may go a long way.
Congenital/Primitive Hydrocephalus: Classification, Clinical Aspects, and Rehabilitation Approach
Authors: Caltabiano Giusi , La Cognata Daria , Zanghì Antonio , Falsaperla Raffaele , Vecchio Michele , Marino Francesco , Palmucci Stefano , Belfiore Giuseppe , Basile Antonio , Polizzi Agata , Praticò Andrea D.
Published: May 2024

Hydrocephalus is a heterogeneous disorder of cerebrospinal fluid (CSF) flow that leads to abnormal enlargement of the brain ventricles. The prevalence of infant hydrocephalus is approximately one case per 1,000 births. Hydrocephalus occurs due to an imbalance between the production and the absorption of CSF. The causes of hydrocephalus secondary to CSF overproduction are papilloma of the choroid plexus and rarely diffuse hyperplasia of the villi. All the other hydrocephalus forms are secondary to obstruction to normal CSF reabsorption and are also known as obstructive hydrocephalus. According to the location of obstruction, obstructive hydrocephalus can be defined as communicating, when caused by extraventricular obstruction of the CSF flow or decreased resorption of CSF distal to the fourth ventricle in the cisterns of the base or in the subarachnoid spaces, or as not communicating, in case of intraventricular obstruction to fluid flow. There is a third category, common in preterm infants, called external hydrocephalus which is secondary to delayed development of arachnoid function. Hydrocephalus leads to an increase in intraventricular pressure because of the lack of the mechanism regulating the homeostasis of the CSF flow. Increased intraventricular pressure is responsible for the clinical symptoms in affected child. Clinical presentation varies with age. In the neonatal period, prolonged or frequent apneic or bradycardic events, increasing head circumference, presence of sunsetting eyes or upward gaze palsy, evidence of full or tense anterior/posterior fontanelle, and splayed cranial sutures are signs of increased intracranial pressure. In infants, the most common signs are progressive macrocephaly, irritability, nausea/vomiting, headache, gait changes, and regression of developmental milestones. The extent of brain damage depends on the cause that led to hydrocephalus, the patient's age, and the rapidity of onset. The surgical treatment modalities consist of endoscopic ventriculostomy of the third ventricle and ventriculoperitoneal or ventriculoatrial CSF shunt.
Microcephaly and Its Related Syndromes: Classification, Genetic, Clinical, and Rehabilitative Considerations
Authors: Di Nora Alessandra , La Cognata Daria , Zanghì Antonio , Vecchio Michele , Chiaramonte Rita , Marino Francesco , Palmucci Stefano , Belfiore Giuseppe , Polizzi Agata , Praticò Andrea D.
Published: May 2024

Microcephaly, a form of cortical cortex malformation, results from abnormal cellular production and proliferation, identified when the occipital frontal head circumference (OFC) falls two or more standard deviations (SDs) below the expected average for age, gender, and population. Severity is classified based on SD: mild (OFC < 2 SD) or severe (OFC < 3 SD). While microcephaly can lead to developmental delay, intellectual disability, epilepsy, and cerebral palsy, not all cases exhibit these issues. Classified as primary/congenital or secondary/postnatal, microcephaly can stem from genetic or acquired factors in both types. Congenital microcephaly origins vary, while secondary microcephaly is characterized by normal OFC at birth, followed by a decrease within the first year, often associated with progressive cognitive and motor impairments. Primary hereditary microcephaly (MCPH), or microcephaly vera, is genetically diverse, with 28 related genes (MCPH1 to MCPH28) encoding proteins linked to centrosomes and progenitor cell mitosis in the brain ventricle's neuroepithelium. Defects in deoxyribonucleic acid (DNA) repair pathways (e.g., NBN, FANCA, ATR, ATM genes) can lead to microcephaly by impairing DNA repair. Enzyme deficiencies in metabolic pathways may also contribute, causing toxic metabolite accumulation or essential metabolite loss (microcephaly of metabolic origin). Acquired congenital microcephaly may result from ischemic or infectious processes, drugs, radiation, maternal diseases during pregnancy, with damage influenced by fetal genetics, environmental interactions, developmental stage, and exposure intensity/duration. Diagnostic workup includes electroencephalogram, ophthalmological, auditory, magnetic resonance imaging, metabolic, echocardiogram, and infection screening tests, alongside genetic evaluations like cytogenetic studies, fluorescence in situ hybridization, comparative genomic microarray-hybridization, single-nucleotide microarray-polymorphism, and exome sequencing. Symptomatic treatment is available, and genetic counseling is crucial for affected families.
Introduction: A Practical Guide to Central Nervous System Malformations—From Genetics, to Diagnosis and Treatment
Authors: Praticò Andrea D. , Polizzi Agata , Ruggieri Martino
Published: May 2024

Central nervous system (CNS) malformations encompass diverse congenital anomalies impacting brain and spinal cord development, profoundly affecting neurological function. They arise from disruptions in embryonic neural tube formation, neuronal migration, and cortical organization. This abstract provides a comprehensive overview of CNS malformations, covering classification, etiology, clinical manifestations, and diagnostic challenges. CNS malformations fall into distinct groups: neural tube defects (e.g., anencephaly, spina bifida), resulting from incomplete neural tube closure; malformations of cortical development (e.g., lissencephaly, polymicrogyria), featuring irregularities in cortical folding; and anomalies affecting structures like the corpus callosum, cerebellum, and CNS vasculature, alongside conditions such as hydrocephalus and Chiari malformations. Genetic factors, including mutations in LIS1, DCX, and RELN, contribute significantly, while environmental factors like maternal folic acid deficiency also play a role. Some malformations occur in genetic syndromes (e.g., tuberous sclerosis, neurofibromatosis). Clinical presentations vary, with neural tube defects typically presenting severe deficits at birth, while cortical malformations manifest as intellectual disabilities, seizures, and motor deficits. Hydrocephalus elevates intracranial pressure, and Chiari malformations cause headaches and neurological symptoms. Diagnosis necessitates a multidisciplinary approach involving clinical evaluation, neuroimaging, genetic testing, and histopathological analysis. Prenatal diagnosis via ultrasound and magnetic resonance imaging is crucial for planning interventions, while postnatal diagnosis relies on clinical and imaging findings.

Understanding CNS malformations is vital for early detection, intervention, and comprehensive care provision. Advances in genetics and neuroimaging offer hope for improved outcomes and better quality of life for affected individuals.
At the Basis of Brain Malformations: Brain Plasticity, Developmental Neurobiology, and Considerations for Rehabilitation
Authors: Polizzi Agata , Ruggieri Martino , Praticò Andrea D. , Leotta Michela , Cavallaro Paola , Sciuto Laura , Vecchio Michele , Di Napoli Claudia
Published: May 2024

From early age in the human brain occurs plasticity process that influences its development. The functioning of the brain is governed by its neuronal connectivity and the synaptic dynamics of these connections. A neuron, over thousands of synapses, can receive a large number of inputs and produce different outputs leading to the consolidation and integration of memory. Synaptic plasticity is the set of experience-dependent changes in neuronal pathways that support acquired habits. It is the ability of the nervous system to reshape connectivity between neurons, changing the functional and structural organization of neuronal circuits that allows us to adapt to the multiple and continuous changes in the environment and leading to processes such as cognitive development and the ability to learn. Synaptic plasticity is mainly due to short- and long-term mechanisms. Short-term synaptic plasticity refers to changes in synaptic strength that occurs very quickly (from one-thousandth of a second to 5 minutes) and are temporary and decay over minutes (maximum 30 minutes). Long-term synaptic plasticity is defined by a long-lasting, activity-dependent change in synaptic efficacy, last from hours up to a lifetime (from 30 minutes to weeks, months, and years) and is thought to constitute the basis of learning and memory. A significant difference occurs in the nature of the change; short-term plasticity adds only a functional change, whereas long-term plasticity causes not only functional but also structural changes. Aside from genetic factors and metabolic processes, brain development is mediated also by environmental factors. Interaction with the environment plays a key role in the development and growth of neural networks and neuroplasticity. Environmental interactions that can modify and increase the development of neural networks and intelligence in children are several and are herein discussed.
Megalencephaly: Classification, Genetic Causes, and Related Syndromes
Authors: Leonardi Roberta , Licciardello Laura , Zanghì Antonio , La Cognata Daria , Maniaci Antonino , Vecchio Michele , Polizzi Agata , Falsaperla Raffaele , Praticò Andrea D.
Published: May 2024

Megalencephaly is a developmental disorder due to an abnormal neuronal proliferation and migration during intrauterine or postnatal brain development that leads to cerebral overgrowth and neurological dysfunction. This cerebral overgrowth may affect the whole encephalon or only a region; when it involves one hemisphere it is referred to as hemimegalencephaly. Megalencephaly presents with a head circumference measurement of 2 standard deviations above the average measure for age. This group of disorders is clinically characterized by early onset and refractory to therapy epilepsy, neurodevelopmental disorders, behavioral problems, and autism spectrum disorder. Syndromic forms of megalencephaly should be considered when associated with other congenital abnormalities. Megalencephaly in fact could be associated with segmental overgrowth and cutaneous/vascular abnormalities (i.e., Proteus syndrome, CLOVES [congenital lipomatous overgrowth, vascular malformations, epidermal naevi, scoliosis, and/ or skeletal abnormalities] syndrome, Klippel-Trenaunay syndrome, megalencephaly-capillary malformation-polymicrogyria syndrome , megalencephaly-postaxial polydactyly-polymicrogyria-hydrocephalus syndrome, etc.) or generalized overgrowth (i.e., Weaver or Beckwith-Wiedemann syndrome) as well as with nanism in achondroplasia where megalencephaly is associated with disproportionate short stature, primary skeletal dysplasia, characteristic facies (prominent forehead, flat nasal bridge), narrow chest, and normal intelligence. It is possible to identify three main groups of disorders associated with megalencephaly: idiopathic or benign, metabolic, and anatomic. The idiopathic (benign) form indicates an abnormal increased head circumference in absence of neurological impairment, such as in benign familial megalencephaly. In metabolic megalencephaly (such as in organic acid disorders, metabolic leukoencephalopathies, or lysosomal diseases) there is an increase of different constituents that increase the size of the brain, whereas in the anatomical form there are underlying genetic causes. Neuroimaging is crucial for diagnosis, as it can reveal a generalized brain growth or a segmental one and possible specific frameworks associated. In all these conditions it is necessary to identify possible microdeletion-microduplication by chromosomal arrays.
Lissencephaly, Pachygyrias, Band Heterotopias, RELN Pathway, and ARX Mutations (Incomplete Neuron Migration)
Authors: Sciuto Laura , Fichera Valeria , Zanghì Antonio , Vecchio Michele , Falsaperla Raffaele , Galioto Sebastiano , Palmucci Stefano , Belfiore Giuseppe , Di Napoli Claudia , Polizzi Agata , Praticò Andrea D.
Published: May 2024

Lissencephaly (LIS) is a group of malformations of cortical development consisting of a defective neuronal migration that results in lack of formation of the normal cerebral convolutions. It includes a spectrum of defect with varying degrees of severity, from agyria and pachygyria to subcortical band heterotopia. The etiopathogenesis of LIS includes both genetic and environmental factors. Although nongenetic forms of LIS have been reported, genetic causes are certainly more frequent and to date 19 LIS-SBH-associated genes have been identified. Most common mutations involve LIS1, DCX, ARX, and RELN genes. Clinically affected individuals present with early hypotonia, which can progress to limb spasticity, seizures, and psychomotor retardation. Convulsive episodes usually appear early (first months of life) and include infantile spasms, akinetic or myoclonic seizures, up to the development of complex epileptic syndromes, including atypical absences, myoclonia, and partial or tonic–clonic seizures. Several clinical entities are associated with classical LIS, including the following: isolated lissencephaly sequence (ILS); Miller–Dieker syndrome (MDS; OMIM 247200); subcortical band heterotopia (OMIM 300067); X-linked LIS with abnormal genitalia; and LIS with cerebellar hypoplasia. Diagnosis primarily depends on genetic and neuroimaging. Magnetic resonance imaging (MRI) is the gold standard, and it detects the presence of thick cortical cortex, its location, and the layers' architecture. Based on neuroimaging, it is possible to distinguish six subtypes of gyral malformations. Clinical and therapeutic management of these patients is challenging, considering the necessity to face drug-resistant epilepsy, intellectual disability, spasticity, and dysphagia and feeding problems. At the present moment, no gene-specific treatment for LIS is available.
Anomalies of the Mesenchyme (Meninges and Skull)—Defects of Neural Tube Closure: Cephalocele and Other Calvarial and Skull Base Defects; Intracranial Lipomas; Arachnoid Cysts; Nonsyndromic and Syndromic Craniosynostoses
Authors: Carnazzo Salvatore , La Cognata Daria , Zanghì Antonio , Marino Francesco , Palmucci Stefano , Belfiore Giuseppe , Basile Antonio , Vecchio Michele , Di Napoli Claudia , Polizzi Agata , Praticò Andrea D.
Published: May 2024

Within the embryonic head, a layer of mesenchyme envelops the brain beneath the surface ectoderm. This cranial mesenchyme is responsible for the formation of the meninges, the calvaria (upper portion of the skull), and the scalp's dermis. Irregular development of these structures, particularly the meninges and the calvaria, is associated with notable congenital defects in humans, such as defects in neural tube closure. Anencephaly is the most common neural tube defect (NTD) and one of the most severe malformations of the central nervous system; it consists in the complete or partial absence of the brain, associated with the absence of the bones of the cranial vault. Iniencephaly is an uncommon congenital NTD characterized by abnormalities in the occipital region, including rachischisis of the cervicothoracic spine and a fixed retroflexion deformity of the head. Unlike anencephaly, in iniencephaly, there is a skull cavity and a normal-looking skin that entirely covers the head and the medullary retroflex area. Cephaloceles are congenital abnormalities distinguished by the protrusion of meninges and/or brain tissue through a naturally occurring defect in the skull bone. This anomaly is typically covered by skin or mucous membrane. Intracranial lipoma is a relatively uncommon and generally benign tumor that occurs in an abnormal location within the brain; it probably represents a disturbance of the differentiation of the primordial meninges: for unknown causes, the meningeal mesenchyme can differentiate into adipose tissue. Arachnoid cysts are sacs filled with cerebrospinal fluid (CSF) situated between the brain or spinal cord and the arachnoid membrane. Typically, these cysts originate within CSF cisterns and gradually expand their boundaries. Craniosynostosis is the early fusion of one or more cranial sutures. It can occur spontaneously, be associated with a syndrome, or have a familial connection. It can involve one or multiple cranial sutures. Pfeiffer's, Crouzon's, and Apert's syndromes are among the more prevalent syndromic craniosynostoses.
Schizencephaly: Etiopathogenesis, Classification, Therapeutic, and Rehabilitative Approach
Authors: Tosto Monica , Fichera Valeria , Zanghì Antonio , Praticò Andrea D. , Vecchio Michele , Palmucci Stefano , Belfiore Giuseppe , Foti Pietro , Di Napoli Claudia , Polizzi Agata
Published: May 2024

Schizencephaly is an uncommon anomaly in neuronal migration characterized by complete clefts that extend from the pia mater to the ependymal surface of the ventricular system. These clefts are encompassed by displaced gray matter and filled with cerebrospinal fluid. Typically, they are found most often in the frontal lobe or the area around the lateral sulcus and can occur on one or both sides. The size, location, and type of these clefts carry significant clinical and prognostic implications. Moreover, they are frequently associated with other central nervous system malformations, including the absence of the septum pellucidum, septo-optic dysplasia, optic nerve hypoplasia, pachygyria, polymicrogyria, cortical dysplasia, heterotopia, and dysplasia of the corpus callosum. Occurrence of schizencephaly is almost always sporadic but its etiopathogenesis is yet to be fully understood. Most likely environmental factors, including exposure to teratogens, viral infections, and maternal factors, operate jointly with genetic defects. To date COL4A1, EMX2, SHH, and SIX3 are the genes identified as possible pathogenetic target. It is interesting to notice that schizencephaly is commonly seen in abandoned or adopted children, as proof of causative effect of intrautero insults. Clinical presentations widely vary and symptoms include a spectrum of cognitive impairment, limb paresis/tetraparesis, and epileptic seizures either with early or late onset; anyway, none of these symptoms is ever-present and patients with schizencephaly can also have normal neurocognitive and motor development. Diagnostic gold standard for schizencephaly is magnetic resonance imaging, which allows to identify and characterize typical clefts. Treatment of schizencephaly is symptomatic and supportive and depends on the severity of morbidity resulting from the malformation. Therapy includes antiepileptic drugs, psychomotor rehabilitation, and in selected cases surgical approach.
Thrombophilia Screening: Not So Straightforward
Authors: Moore Gary W.
Published: May 2024

Although inherited thrombophilias are lifelong risk factors for a first thrombotic episode, progression to thrombosis is multifactorial and not all individuals with inherited thrombophilia develop thrombosis in their lifetimes. Consequently, indiscriminate screening in patients with idiopathic thrombosis is not recommended, since presence of a thrombophilia does not necessarily predict recurrence or influence management, and testing should be selective. It follows that a decision to undertake laboratory detection of thrombophilia should be aligned with a concerted effort to identify any significant abnormalities, because it will inform patient management. Deficiencies of antithrombin and protein C are rare and usually determined using phenotypic assays assessing biological activities, whereas protein S deficiency (also rare) is commonly detected with antigenic assays for the free form of protein S since available activity assays are considered to lack specificity. In each case, no single phenotypic assay is capable of detecting every deficiency, because the various mutations express different molecular characteristics, rendering thrombophilia screening repertoires employing one assay per potential deficiency, of limited effectiveness. Activated protein C resistance (APCR) is more common than discrete deficiencies of antithrombin, protein C, and protein S and also often detected initially with phenotypic assays; however, some centres perform only genetic analysis for factor V Leiden, as this is responsible for most cases of hereditary APCR, accepting that acquired APCR and rare F5 mutations conferring APCR will go undetected if only factor V Leiden is evaluated. All phenotypic assays have interferences and limitations, which must be factored into decisions about if, and when, to test, and be given consideration in the laboratory during assay performance and interpretation. This review looks in detail at performance and limitations of routine phenotypic thrombophilia assays.
Role of Retrograde Tibiopedal Access in Limb Salvage in Patients with Critical Lower Limb Ischemia
Authors: Ghoneim Baker M. , Elhindawy Khaled M. Abdo , Fouad Fouad S. , Ellil Mostafa H. Abo , Shaker Ahmed A.
Published: May 2024

The aim of this study was to assess the efficacy and safety of retrograde tibiopedal access as an alternative approach in cases of critical limb ischemia (CLI) when antegrade access has failed. A prospective study was conducted that included patients with CLI who underwent tibiopedal access after failed antegrade recanalization from January 2018 to June 2022. Follow-up was conducted at 6, 12, and 24 months. The primary outcomes evaluated were technical success rate and primary patency. Secondary outcomes included complication rate, mortality rate, and limb salvage rate (LSR). Forty-eight patients had CLI and Trans Atlantic Inter-Society Consensus infrainguinal lesions. The retrograde approach was used through the anterior tibial artery in 28 patients (58%), the posterior tibial artery in 18 patients (37.5%), and the peroneal artery in 2 patients (4.5%). Technical success was achieved in 90% of patients (43 patients). There was a significant increase in the anklebrachial index after the procedure with a mean follow-up of 22 months. Twenty-two months primary patency rate was 85.2%, while secondary patency rate was 100% and LSR was 96%, respectively. There was no mortality in the series. Retrograde tibiopedal approach is an alternative option for managing peripheral arterial disease and CLI. This method offers another means of crossing lesions when antegrade access failed, and the intervention can be completed either in an antegrade or retrograde approach. As the retrograde approach does not impact access site, considered a feasible safe treatment alternative which increase the success rate of endovascular treatment.
Obesity-Related Traits Mediate the Effects of Educational Attainment on the Risk of Varicose Veins, Venous Thromboembolism, and Phlebitis
Authors: Du Hong-Cheng , Deng Bai-Yang
Published: May 2024

Background The extent to which educational attainment (EA) influences the risk of varicose veins (VVs), venous thromboembolism (VTE), and phlebitis occurrence, whether this pathway is mediated by obesity-related traits, and the proportion of their mediation is unknown.

Methods A Mendelian randomization (MR) design was used to genetically investigate the causal effects of EA on the risk of VV, VTE, and phlebitis and to assess the mediating effect of obesity-related traits. Causal effects were estimated using primarily the multiplicative random-effects inverse variance-weighted method. This was supplemented by Cochran's Q-statistic, MR–Egger regression, MR funnel plots, and leave-one-out test to evaluate the reliability of the results. For the individual mediation effect, the coefficient product method was mainly utilized to estimate.

Results An increase in genetically predicted EA was associated with a lower risk of VV, VTE, and phlebitis, as well as lower body mass index, basal metabolic rate, hip circumference, and waist circumference. As genetically predicted body mass index, basal metabolic rate, hip circumference, and waist circumference increased, the risk of developing VV, VTE, and phlebitis increased, respectively. Body mass index, basal metabolic rate, hip circumference, and waist circumference were identified as mediators of the protective effects of EA on VV, VTE, and phlebitis.

Conclusion The findings support a causal relationship between higher EA and lower risk of VV, VTE, and phlebitis. Obesity-related traits play a significant mediating role in these pathways, and there are interactions between them, with hip circumference mediating these pathways relatively independently from the other three.
On the running and the UV limit of Wilsonian renormalization group flows
Authors: László András , Tarcsay Zsigmond
Published: May 2024

In nonperturbative formulation of quantum field theory, the vacuum state is characterized by the Wilsonian renormalization group (RG) flow of Feynman type field correlators. Such a flow is a parametric family of ultraviolet (UV) regularized field correlators, the parameter being the strength of the UV regularization, and the instances with different strength of UV regularizations are linked by the renormalization group equation. Important RG flows are those which reach out to any UV regularization strengths. In this paper it is shown that for these flows a natural, mathematically rigorous generally covariant definition can be given, and that they form a topological vector space which is Hausdorff, locally convex, complete, nuclear, semi-Montel, Schwartz. That is, they form a generalized function space having favorable properties, similar to multivariate distributions. The other theorem proved in the paper is that for Wilsonian RG flows reaching out to all UV regularization strengths, a simple factorization formula holds in case of bosonic fields over flat (affine) spacetime: the flow always originates from a regularization-independent distributional correlator, and its running satisfies an algebraic ansatz. The conjecture is that this factorization theorem should generically hold, which is worth future investigations.
Existence of density inhomogeneity of liquid Te associated with liquid–liquid phase transition
Authors: Kajihara Yukio , Inui Masanori , Matsuda Kazuhiro , Ohara Koji
Published: May 2024

We performed small-angle x-ray scattering measurements of liquid Te using a synchrotron radiation facility and observed maximum scattering intensity near 620 K in the supercooled region (melting temperature 723 K). This indicates that density inhomogeneity exists in liquid Te, and the fact that this temperature coincides with the temperature at which the specific heat, sound velocity, and thermal expansion coefficient reach their maxima means that this density inhomogeneity is the cause of these thermodynamic anomalies. The thermodynamic anomalies in liquid Te had already been shown in the 1980s to be comprehensively explained by the inhomogeneity associated with the continuous liquid–liquid phase transition (LLT), but direct experimental evidence for the existence of the inhomogeneity had not been obtained. The present results, together with those already obtained for mixture systems (Te–Se, Te–Ge), indicate the existence of inhomogeneity associated with LLT in liquid Te systems, and strongly support the model. Recently, similar maximum scattering intensity has also been observed in supercooled liquid water, which exhibits thermodynamic anomalies similar to those of Te, indicating the universality of the inhomogeneous model or LLT scenario to explain the thermodynamics of such ‘anomalous liquids’. Further development of the LLT scenario is expected in near future.
Study of conduction mechanisms of InSeSb nano-chalcogenide alloys
Authors: Thakur Diksha , Rangra Vir Singh
Published: May 2024

The electrical conduction mechanisms for bulk samples of In0.1Se0.9−x
Sb
x
(x = 0, 0.04, 0.08 and 0.12) nano-chalcogenide system, synthesized by the melt-quenching technique are investigated through current–voltage (I–V) characteristics. For the detailed study of conduction mechanism pellets of bulk samples are prepared. A thorough examination of electrical conductivity is done in the temperature range of 295–318 K and 0–50 V voltage range. From I–V measurements it is observed that samples are showing ohmic nature at lower field and non-ohmic nature at relatively higher field values. The temperature dependence of DC conductivity is analyzed using the Arrhenius relationship which is found to increase with Sb content. The value of activation energy and pre-exponential factor are calculated, which revealed that the conduction is due to the hopping of charge carriers among the localized states. Different parameters of Mott’s variable range hopping such as degree of disorder T
0, density of localized states N(E
F), hopping distance (R
hop), and hopping energy (W) are calculated. For the high field conduction process Poole–Frenkel, and Schottky processes are studied.
Modulating electronic structure by interlayer spacing and twist on bilayer bismuthene
Authors: Zhang Hongfei , Cheng Shuwei , Chen Yuanping , Chu Shibing
Published: May 2024

Modulation of the electronic structure has played a crucial role in advancing the field of two-dimensional materials, but there are still many unexplored directions, such as the twist angle for a novel degree of freedom, for modulating the properties of heterostructures. We observed a distinct pattern in the energy bands of bilayer bismuthene, demonstrating that modulating the twist angle and interlayer spacing significantly influences interlayer interactions. Our study of various interlayer spacings and twist angles revealed a close relationship between bandgap size and interlayer spacing, while the twist angle notably affects the shape of the energy bands. Furthermore, we observed a synergistic effect between these two factors. As the twist angle decreases, the energy bands become flat, and flat bands can be generated without requiring a specific angle on bilayer bismuthene. Our results suggest a promising way to tailor the energy band structure of bilayer 2D materials by varying the interlayer spacing and twist angle.
Multiparameter measurement depending on the cavity-length differentiation characteristics of a microfiber Fabry–Perot interferometer
Authors: Liu Fangfang , Ran Xin , Liu Xinyang , Jiang Ying , Yan Pen , Li Shizhao , Li Hongli , Zhao Huining , Xia Haojie
Published: May 2024

To solve the cross-sensitivity problem affecting optical fiber sensors and realize multiparameter measurement, a microfiber Fabry–Perot interferometer (MFPI) is proposed and experimentally demonstrated. Simultaneous measurement of two distinct physical parameter (temperature and strain) is realized by monitoring wavelength and reflectivity of MFPI. In the temperature field range of 22 °C–36 °C, the maximum temperature sensitivity can reach 12 pm °C−1. The maximum strain sensitivity is up to 0.8 pm/μϵ in the strain range of 0–800 μϵ. In the simultaneous measurement experiments, the relative errors of temperature and strain were 4.0% and 0.8%, respectively. Furthermore, the sensing element used in this method was just a single fiber grating sensor without any coating layer, which demonstrated the significant advantage of the proposed method in reducing the complexity and cost of multiparameter measurement.
Radial vibration measurement of rotating shaft using constant density fringe pattern and line scan camera
Authors: Huang Yuexin , Liu Dongming , Zhong Jianfeng , Zhong Shuncong
Published: May 2024

The radial vibration signals of the rotor can provide abundant information about the health condition of the machine. In this paper, a simple vision-based measurement system is proposed to simultaneously measure two-dimensional displacements in radial directions for the rotating shaft, where the system consists of a constant density fringe pattern (CDFP), a line scan camera (LSC), and a lens. The CDFP should be installed around the surface of the rotating shaft to make the density of the fringe constant along the shaft axis, while the shaft axis is vertical to the optical axis of the LSC but not parallel to the line-array sensor of the LSC. Therefore, the density of the fringe imaged on the LSC is not constant because of the modulation of the circular surface of the shaft, and the distribution of the fringe density on the LSC is a U-shaped curve. Thus, the shaft centreline orbit can be tracked by the lowest point of the density distribution curve (DDC) of the fringe. Then, an efficient and accurate parameterized instantaneous frequency estimation method is employed to estimate the DDC of the fringe, because the variable density fringe can be regarded as an amplitude-modulated and frequency-modulated nonstationary signal whose instantaneous frequency function is equivalent to the DDC. Experimental results verify the feasibility and effectiveness of the proposed method by comparing it to the eddy current sensors.
Fluorescence lifetime of plant leaves with sub-nanosecond resolution
Authors: Illés L , Sági-Kazár M , Steinbach F , Hembrom R , Mihailova G , Georgieva K , Solymosi K , Barócsi A , Solti Á , Lenk S
Published: May 2024

The study aimed to develop a measurement apparatus for in vivo chlorophyll-a (Chl-a) fluorescence decay measurements of plants by means of time correlated single photon counting. In this approach, sub-nanosecond laser pulses with a repetition rate of 10 MHz are applied to excite the sample, followed by the analysis of arrival times of the emitted fluorescence photons. Photon statistics are generated by iteratively fitting the sum of two exponential functions. The tool was tested on both plastid and in vivo leaf samples of Savoy cabbage (Brassica oleracea var. sabauda) with 3–4 subsequent leaves giving a complete sample coverage starting from the outermost. The Chl-a fluorescence lifetime exhibited a gradual increase in both the isolated plastid suspensions and the in vivo leaf samples towards the innermost leaf layers explained by an increase of natural absence of light (etiolation syndrome). Furthermore, cadmium stress and iron deficiency were investigated on treated sugar beet (Beta vulgaris) samples in vivo using TCSPS measurements. The reduced fluorescence quenching resulted in an increased fluorescence lifetime. Finally, a long-term (10 week) testing of the setup was carried out on Chl-retaining resurrection Haberlea rhodopensis plants protecting themselves by an elevated non-photochemical quenching yielding a decrease of fluorescence lifetime during their desiccation.
A reference-point-method-based online proton treatment plan re-optimization strategy and a novel solution to planning constraint infeasibility problem
Authors: Qiu Zihang , Depauw Nicolas , Gorissen Bram L , Madden Thomas , Ajdari Ali , den Hertog Dick , Bortfeld Thomas
Published: May 2024

Objective. Propose a highly automated treatment plan re-optimization strategy suitable for online adaptive proton therapy. The strategy includes a rapid re-optimization method that generates quality replans and a novel solution that efficiently addresses the planning constraint infeasibility issue that can significantly prolong the re-optimization process. Approach. We propose a systematic reference point method (RPM) model that minimizes the l-infinity norm from the initial treatment plan in the daily objective space for online re-optimization. This model minimizes the largest objective value deviation among the objectives of the daily replan from their reference values, leading to a daily replan similar to the initial plan. Whether a set of planning constraints is feasible with respect to the daily anatomy cannot be known before solving the corresponding optimization problem. The conventional trial-and-error-based relaxation process can cost a significant amount of time. To that end, we propose an optimization problem that first estimates the magnitude of daily violation of each planning constraint. Guided by the violation magnitude and clinical importance of the constraints, the constraints are then iteratively converted into objectives based on their priority until the infeasibility issue is solved. Main results. The proposed RPM-based strategy generated replans similar to the offline manual replans within the online time requirement for six head and neck and four breast patients. The average target D
95 and relevant organ at risk sparing parameter differences between the RPM replans and clinical offline replans were −0.23, −1.62 Gy for head and neck cases and 0.29, −0.39 Gy for breast cases. The proposed constraint relaxation solution made the RPM problem feasible after one round of relaxation for all four patients who encountered the infeasibility issue. Significance. We proposed a novel RPM-based re-optimization strategy and demonstrated its effectiveness on complex cases, regardless of whether constraint infeasibility is encountered.
Directional TV algorithm for image reconstruction from sparse-view projections in EPR imaging
Authors: Qiao Zhiwei , Liu Peng , Fang Chenyun , Redler Gage , Epel Boris , Halpern Howard
Published: May 2024

Objective. Electron paramagnetic resonance (EPR) imaging is an advanced in vivo oxygen imaging modality. The main drawback of EPR imaging is the long scanning time. Sparse-view projections collection is an effective fast scanning pattern. However, the commonly-used filtered back projection (FBP) algorithm is not competent to accurately reconstruct images from sparse-view projections because of the severe streak artifacts. The aim of this work is to develop an advanced algorithm for sparse reconstruction of 3D EPR imaging. Methods. The optimization based algorithms including the total variation (TV) algorithm have proven to be effective in sparse reconstruction in EPR imaging. To further improve the reconstruction accuracy, we propose the directional TV (DTV) model and derive its Chambolle–Pock solving algorithm. Results. After the algorithm correctness validation on simulation data, we explore the sparse reconstruction capability of the DTV algorithm via a simulated six-sphere phantom and two real bottle phantoms filled with OX063 trityl solution and scanned by an EPR imager with a magnetic field strength of 250 G. Conclusion. Both the simulated and real data experiments show that the DTV algorithm is superior to the existing FBP and TV-type algorithms and a deep learning based method according to visual inspection and quantitative evaluations in sparse reconstruction of EPR imaging. Significance. These insights gained in this work may be used in the development of fast EPR imaging workflow of practical significance.
Comparison of admittance and cardiac magnetic resonance generated pressure-volume loops in a porcine model
Authors: Andersen Stine , Laursen Pernille Holmberg , Wood Gregory John , Lyhne Mads Dam , Madsen Tobias Lynge , Hansen Esben Søvsø Szocska , Johansen Peter , Kim Won Yong , Andersen Mads Jønsson
Published: May 2024

Objective. Pressure-volume loop analysis, traditionally performed by invasive pressure and volume measurements, is the optimal method for assessing ventricular function, while cardiac magnetic resonance (CMR) imaging is the gold standard for ventricular volume estimation. The aim of this study was to investigate the agreement between the assessment of end-systolic elastance (Ees) assessed with combined CMR and simultaneous pressure catheter measurements compared with admittance catheters in a porcine model. Approach. Seven healthy pigs underwent admittance-based pressure-volume loop evaluation followed by a second assessment with CMR during simultaneous pressure measurements. Main results. Admittance overestimated end-diastolic volume for both the left ventricle (LV) and the right ventricle (RV) compared with CMR. Further, there was an underestimation of RV end-systolic volume with admittance. For the RV, however, Ees was systematically higher when assessed with CMR plus simultaneous pressure measurements compared with admittance whereas there was no systematic difference in Ees but large differences between admittance and CMR-based methods for the LV. Significance. LV and RV Ees can be obtained from both admittance and CMR based techniques. There were discrepancies in volume estimates between admittance and CMR based methods, especially for the RV. RV Ees was higher when estimated by CMR with simultaneous pressure measurements compared with admittance.
A novel double-gate trench SOI LDMOS with double-dielectric material by TCAD simulation study
Authors: Guo Jinjun , Dai Hongli , Wang Luoxin , Xue Yuming , Lyu Haitao , Niu Wenze
Published: May 2024

In this paper, a novel double-gate trench silicon-on-insulator lateral double-diffused metal oxide semiconductor field-effect transistor (LDMOS) with double-dielectric material (DGDK-LDMOS) is proposed. DGDK-LDMOS has two dielectric materials: a reverse-L-shaped high-k (HK) thin film and an low-k (LK) buried oxide layer. The HK thin film optimizes the electric field distribution on the drift region surface, attracting electric flux, and the excellent withstand voltage of the LK buried oxide layer can significantly improve the breakdown voltage (BV) and reduce specific on-resistance (R
on,sp) of the device. The modulation mechanism of LDMOS by HK thin film and LK buried oxide layer is analyzed. The results show that compared with conventional LDMOS, when the permittivity of HK thin film is 25 and the permittivity of LK buried oxide is 3, the BV of DGDK-LDMOS is increased by 89.6%, the R
on,sp is decreased by 26.4%, and the figure of merit (FOM, FOM = BV2/R
on,sp) is increased by 397.2% from 3.6 MW cm−2 to 17.9 MW cm−2. Meanwhile, the output characteristics, transfer characteristics, lattice temperature, AC characteristics and switching characteristics of DGDK-LDMOS are also discussed and compared.
Self-centering of steel braced frames equipped with Fe-SMA TADAS dampers
Authors: Torabizadeh Amirreza , Foyouzat Alireza , Asghari Abazar , Mohammadi Soheil
Published: May 2024

This study proposes a novel triangular added damping and stiffness (TADAS) damper that uses the shape memory effect of iron-based shape memory alloy (Fe-SMA) to provide a self-centering system to recover the initial shape of a structure after significant inelastic deformation induced by nonlinear response of fused elements, without the need for difficult and expensive replacement procedures of conventional TADAS systems. Unlike most studies which consider simplified uniaxial behavior of Fe-SMAs, the present non-linear finite element simulations cover the full 3D material non-linearity of Fe-SMA component based on the SMA constitutive law to capture both flexural and shear behavior in various coupled thermomechanical loadings, including the mechanical loading/unloading, the heating, and the final cooling (as the recovering process). Simulations performed on a one-bay steel frame for different drift ratios reveal that although the dissipation energy of the new device is at most 10% less than the ordinary one, it enjoys the self-centering property to recover the initial shape of the frame before loading, showing that the proposed damper is an effective alternative to ordinary TADAS yielding dampers to achieve the self-centering characteristics.