Search Results (753)

In the past hundred years, three pontiffs have written apostolic letters to commemorate anniversaries relating to Dante: in 1921, Benedict XV marked the sixth centenary of the death of the great poet; in 1965, Paul VI judged it opportune to write on the occasion of the seventh centenary of his birth; and in 2021, Pope Francis added his voice to the numerous others wishing to honour the memory of the supreme Florentine poet on the seventh centenary of his death. Each letter is a product of its time: one hundred years ago, the Pope—still confined within the Vatican and refusing to recognise the Kingdom of Italy due to the Roman Question—addressed his text “to the beloved sons, professors and pupils of literary institutes and centres of higher learning within the Catholic world”; Paul VI, in full accord with the spirit of the Second Vatican Council and its vision of a Church seeking collaboration with the world, addressed his writing to Dante scholars more broadly, and within the same letter, together with other academic authorities, established the Chair of Dante Studies at the Catholic University of the Sacred Heart in Milan; Pope Francis today, in his outward-facing style of evangelisation, challenges everyone to (re)read Dante, whose teaching remains relevant seven hundred years after his death. Despite the differing political contexts and ecclesial agendas, Benedict XV, Paul VI, and Pope Francis are united on one point: Dante is a Christian poet—critical of the Church, certainly, but loyal to his faith and desirous of a religious institution that is more serious and less corrupt. This brief study presents the homage which the Church, today, seven centuries later, renders to this Poet—now widely recognised as a passionate witness of an arduous and active faith, in pursuit of justice and freedom. Full article

This study applies stochastic discrete event modeling to demonstrate that reducing wait times for specialized outpatient clinics in the Costa Rican public healthcare system is possible. The classification process identified four medical specialties with the longest wait times. It includes the creation of a separate queuing theory model for each specialty. The birth and death model allowed for estimating the number of arrivals and consultations in the simulation. Validation was performed by comparing the model’s input and output data with real-world statistical reports. An analysis of medical specialists revealed that approximately 22% of patients referred to secondary care did not require specialized medical consultation. Through simulation and the use of stochastic input data, patient waiting times decreased. In an optimistic scenario, waiting times decreased steadily across all specialties over 24 months. Ophthalmology and orthopedics reduced their waiting times to less than 300 days. Otorhinolaryngology decreased from 370 to 250 days, and urology showed the most significant improvement, decreasing from 350 to 100 days in the first year and remaining stable. This evidence transforms the traditional paradigm of increasing capacity as the only solution to the waiting list problem and positions improving the referral process as an alternative. To achieve these results, the study highlights the importance of implementing improved triage protocols in primary care, integrating decision-support tools for general practitioners using machine learning, for example, to reduce unnecessary referrals. Training programs and feedback mechanisms could also align referral practices with specialty criteria. While these strategies were not implemented in this study, the simulation results provide a solid basis for their design and future evaluation. Full article

Background/Objectives: Renal transplantation (RT) represents the optimal treatment for end-stage renal disease (ESRD), offering improved quality of life and restored fertility in women post-transplant. While post-transplant pregnancies are possible, they can lead to complications including pre-eclampsia, graft dysfunction, and other adverse outcomes. This study evaluates existing literature to assess pregnancy’s impact on kidney transplantation outcomes, specifically long-term graft function and survival. Methods: We conducted a systematic review of English-language literature from January 2000 to September 2023 across multiple databases, following PRISMA guidelines. We established inclusion criteria focusing on graft function and adverse events. Two independent reviewers performed data extraction, and we assessed risk of bias using the ROBINS-I tool. Results: From 4917 articles, we included 26 studies encompassing 1202 pregnancies in 902 kidney transplant recipients. Mean maternal age was 30.8 years, with an average interval of 52 months between transplant and pregnancy. Pre-pregnancy hypertension occurred in 54.2% of cases, and pre-eclampsia developed in 25.7%. The live birth rate reached 70.5%, while miscarriage, stillbirth, and neonatal death rates were 11.3%, 2.7%, and 2.5%, respectively. We noticed graft dysfunction during pregnancy in 20.2% of cases. Though kidney function often deteriorated temporarily, most patients recovered post-delivery. Discussion: Post-transplant pregnancies remain viable but high-risk, with elevated rates of obstetric complications. Our findings highlight the need for standardized data collection and reporting to better understand and manage pregnancy’s impact on graft outcomes. Conclusions: With appropriate management, pregnancy in kidney transplant recipients is feasible, though it carries elevated risks of obstetric complications. We recommend further multicenter studies with standardized data collection to improve understanding and outcomes. Full article

Objectives: Pulmonary hypertension and hemodynamically significant PDA (hsPDA) involve seemingly opposite physiological features—decreased pulmonary blood flow and pulmonary overcirculation, respectively—but the literature demonstrates variable respiratory consequences in association with each of these morbidities. The aim of this study is to evaluate whether the two factors representing pulmonary circulation provide different contributions to respiratory outcomes in preterm infants with and without pulmonary hypoplasia. Methods: The medical records of preterm very low birth weight (VLBW) infants admitted to our unit during the study period from January 2013 to December 2020 were retrospectively reviewed. Preterm VLBW infants were divided into groups according to the presence of presumed pulmonary hypoplasia (PPH). Multivariable logistic regression analysis was performed to assess the association of PPH and pulmonary hypertension or delayed PDA closure with in-hospital outcomes. Results: Postnatal age at final treatment for PDA was significantly later [median 33 vs. 19 days, p = 0.025] in the PPH group. Multivariable analysis indicated that early pulmonary hypertension was significantly associated with neonatal death [aOR (95%CI) 11.575 (2.988–44.833) for no-PPH vs. 9.981 (1.334–74.647) for PPH]. Delayed PDA closure was associated with increased odds of adverse respiratory and composite outcomes [aOR (95%CI) 4.929 (1.613–15.055) and 3.320 (1.048–10.515), respectively] but decreased odds of neonatal death in the no-PPH group. However, Cox proportional hazards models did not demonstrate statistically significant associations for PPH, early pulmonary hypertension, or delayed PDA closure with mortality, likely due to time-varying effects and the absence of death events in the subgroup of infants with both PPH and delayed PDA closure. Conclusions: PPH is associated with a higher prevalence of air leak syndrome and pulmonary hypertension. Delayed PDA closure exerts different effects on respiratory outcomes in preterm VLBW infants with and without PPH. Although early pulmonary hypertension appears to be a key circulatory factor contributing to neonatal death, its effect may vary over time. These findings underscore the importance of accounting for time-dependent effects when interpreting pulmonary circulatory risk factors in clinical practice. Full article

Neonatal calves possess an immature and naïve immune system and are reliant on the intake of maternal colostrum for the passive transfer of immunoglobulins. Maternal antibodies delivered to the calf via colostrum, are crucial to prevent calfhood diseases and death. Failure of transfer of passive immunity (FTPI) is a condition in which calves do not acquire enough maternal antibodies, mostly in the form of IgG, due to inadequate colostrum quality or delayed colostrum feeding. The diagnosis and risk factors for FTPI have been widely studied in dairy cattle; however, in beef calves, the research interest in the topic is relatively recent, and the most adequate diagnostic and preventative methods are still in development, making it difficult to define recommendations for the assessment and prevention of FTPI in cow–calf operations. The objective of this scoping review is to identify the published literature on best practices for colostrum management and transfer of passive immunity (TPI) in neonatal beef calves. The literature was searched using three electronic databases (CAB Direct, Scopus, and PubMed) for publications from 2003 to 2025. The search process was performed during the period from May to July 2023, and was repeated in January 2025. All screening processes were performed using Covidence systematic review software (Veritas Health Innovation, Melbourne, Australia). A total of 800 studies were initially identified through database searches. After removing duplicates, 346 studies were screened based on their titles and abstracts, leading to the exclusion of 260 studies. The remaining 86 studies underwent full-text screening, and 58 studies were considered eligible for data extraction. Hand-searching the references from published review papers on the subject yielded an additional five studies, bringing the total to 63 included articles. The prevalence of FTPI has been estimated to be between 5.8% and 34.5% in beef calves. Factors studied related to colostrum management include quality and quantity of colostrum intake, the timing and method of colostrum feeding, and the microbial content of the colostrum. Studies on risk factors related to the calf include the topics calf sex, twin status, calf vigor, weight, month of birth, cortisol and epinephrine concentrations, and the administration of nonsteroidal anti-inflammatory drugs to calves after difficult calving. The dam-related risk factors studied include dam body condition score and udder conformation, breed, parity, genetics, prepartum vaccinations and nutrition, calving area and difficulty, and the administration of nonsteroidal anti-inflammatory drugs at C-section. Most importantly for beef systems, calves with low vigor and a weak suckling reflex are at high risk for FTPI; therefore, these calves should be given extra attention to ensure an adequate consumption of colostrum. While serum IgG levels of < 8 g/L or < 10 g/L have been suggested as cutoffs for the diagnosis of FTPI, 16 g/L and 24 g/L have emerged as cutoffs for adequate and optimal serum IgG levels in beef calves. Several field-ready diagnostics have been compared in various studies to the reference standards for measuring indicators of TPI in beef calves, where results often differ between models or manufacturers. Therefore, care must be taken when interpreting these results. Full article

Background and aim: The death of a woman while pregnant or within 42 days of delivery, regardless of the cause of death, or even up to one year after the end of the pregnancy, due to causes related to or aggravated by pregnancy remains a critical public health problem globally and in Colombia. While the country shows a general decreasing trend (preliminary Maternal Mortality Ratio 38.6/100,000 live births in 2023), significant regional disparities persist. Understanding precise underlying causes, especially in high-complexity referral centers, is vital. This study describes the sociodemographic and anatomopathological characteristics associated with autopsy-verified maternal mortality cases at a Level-4 hospital in southwestern Colombia (2000–2023). Methodology: A descriptive observational retrospective study analyzed 42 maternal mortality cases verified by clinical autopsy (2000–2023) at the Pathology Department of Universidad del Valle, a Level-4 referral center in Cali, Colombia. Cases met the WHO definition. Data on sociodemographic, clinical, and pathological characteristics were retrospectively extracted from clinical records and autopsy reports. Results: The analysis of 42 autopsies (2000–2023) showed that 85.7% were early maternal deaths. Indirect causes predominated (57.1%, n = 24) over direct (42.9%, n = 18). Septic shock was the main indirect cause (65.2% of indirect), often from endemic infections. Hypovolemic shock due to PPH was the main direct cause (50% of direct). A high proportion were from subsidized/uninsured schemes (65.7%) and had a migratory history (20%). Discussion and conclusions: This study highlights the value of autopsy in revealing maternal mortality etiologies, showing a predominance of indirect/infectious causes and endemic diseases often missed clinically, despite PPH remaining the main direct cause. Findings reaffirm the strong link between maternal death and social/economic inequity, access barriers, and regional/migratory vulnerabilities. Effectively reducing maternal mortality necessitates rigorous clinical management, regionalized public health strategies addressing inequities, and integrating pathological data for targeted surveillance. Full article

We develop a symmetry-based variational theory that shows the coarse-grained balance of work inflow to heat outflow in a driven, dissipative system relaxed to the golden ratio. Two order-2 Möbius transformations—a self-dual flip and a self-similar shift—generate a discrete non-abelian subgroup of $\mathrm{PGL}(2,\mathbb{Q}\left(\sqrt{5}\right))$. Requiring any smooth, strictly convex Lyapunov functional to be invariant under both maps enforces a single non-equilibrium fixed point: the golden mean. We confirm this result by (i) a gradient-flow partial-differential equation, (ii) a birth–death Markov chain whose continuum limit is Fokker–Planck, (iii) a Martin–Siggia–Rose field theory, and (iv) exact Ward identities that protect the fixed point against noise. Microscopic kinetics merely set the approach rate; three parameter-free invariants emerge: a $62\%:38\%$ split between entropy production and useful power, an RG-invariant diffusion coefficient linking relaxation time and correlation length ${\mathcal{D}}_{\alpha }={\xi }^z/\tau$, and a $\vartheta ={45}^{\circ }$ eigen-angle that maps to the golden logarithmic spiral. The same dual symmetry underlies scaling laws in rotating turbulence, plant phyllotaxis, cortical avalanches, quantum critical metals, and even de-Sitter cosmology, providing a falsifiable, unifying principle for pattern formation far from equilibrium. Full article

Background: Human cytomegalovirus (HCMV) is the leading cause of congenital and acquired viral infections in newborns. While acquired infections are often asymptomatic, premature infants—especially those born before 30 weeks of gestation or with a very low birth weight (<1500 g)—are at an increased risk for severe infections. These can manifest as thrombocytopenia, liver failure, sepsis-like symptoms, and, in rare cases, death. HCMV is transmitted through various human secretions, including breast milk, which is the optimal feeding method for premature infants. Methods: We present five premature neonates, born between 23 and 26 weeks of gestation, each with a distinct clinical presentation of acquired HCMV infection. Results: All infants tested negative for congenital CMV infection via molecular urine testing within the first three weeks of life. Acquired infection was diagnosed between the second and third month of life, with symptoms such as septic shock, persistent thrombocytopenia, and signs of liver failure. Each infant received antiviral treatment along with regular viral load monitoring. Unfortunately, one patient died due to complications of prematurity. The remaining infants were discharged and continue to receive follow-up care in an outpatient clinic. Conclusions: These cases of postnatally acquired CMV infection aim to increase awareness of its highly heterogeneous and nonspecific clinical presentation, which may result in an incorrect, delayed, or concealed diagnosis. Currently, there are no clear guidelines on how to manage the presence of the virus in maternal breast milk, particularly for premature infants. It should be recommended to perform a molecular CMV test in all breast-fed preterm infants who present with sepsis-like symptoms, thrombocytopenia, liver failure, or other organ involvement. In case of a confirmed aCMV diagnosis, appropriate treatment should be introduced. Full article

Consanguinity is the marriage of two related persons. This type of marriage is one of the main pillars when it comes to recessive hereditary diseases, birth defects, infertility, miscarriages, abortion, and infant deaths. Intermarriage continues to be a common practice in various communities in North Africa, the Middle East, and West and South Asia, as well as among migrants from Europe and North America, even though in more and more countries it has become illegal. Even if security and stability are some of the motivations for consanguineous marriage, studies show that women often suffer physical and verbal abuse from their husbands. However, because of the blood bond, tolerance for these habits is much higher. In addition, it seems that the divorce rate is much lower because separation would affect the entire state of the family. The choice of partner is significantly influenced by variables such as limited access to education and financial resources. Illiterate people coming from poor rural areas are much more likely to choose consanguineous marriage to maintain wealth in the family. The lack of medical knowledge about the negative effects of consanguinity leads to an increased rate of abortions, infant deaths, and births of children with congenital birth defects. Today, because of the process of urbanization and increased levels of knowledge, the younger generation is becoming increasingly less receptive to this particular form of marriage. In addition, as education has become more accessible to women, they have become more independent and eager to fulfill their own goals and not the wishes of the family. In conclusion, contrary to the many apparent advantages of consanguineous marriage, partners should put genetic risks first, as medical problems bring with them increased costs in the medical system and also within the family, leading to even lower economic status and consequently perpetuation of this type of marriage. Full article

Welding and cutting behaviour may affect the mechanical properties of titanium alloy welded structures, which may have some impact on the safety assessment of the structure. This study analyses changes in residual stress in Ti80 butt-welded thick plates before and after wire-cut electric discharge machining, using numerical simulations based on thermo-elastoplastic theory and the element birth and death method, validated by X-ray non-destructive testing. The transverse residual tensile stress near the weld exhibits an asymmetric bimodal distribution, while the longitudinal stress is significantly higher than the transverse stress. Wire-cut electric discharge machining had minimal influence on the transverse residual stress distribution but led to partial relief of the longitudinal residual tensile stress. The maximum reductions in transverse and longitudinal welding residual tensile stresses are approximately 60% and 36%, respectively. The findings indicate that wire-cut electric discharge machining can alter surface residual stresses in Ti alloy butt-welded thick plates. This study also establishes a numerical simulation methodology for analysing welding residual stresses and their evolution due to wire-cut electric discharge machining. The results provide a theoretical basis for analysing the structural strength and safety of Ti-alloy-based deep-sea submersibles. Full article

Background: Respiratory syncytial virus (RSV) remains a leading cause of lower respiratory tract infections and hospitalizations in infants and young children globally. Recently, RSV prevention has advanced with the introduction of nirsevimab, a long-acting monoclonal antibody, and the RSV preF vaccine for maternal immunization. While these interventions have improved early protection, several limitations hinder their broader impact and long-term effectiveness. Methods: This narrative review synthesizes evidence from clinical trials, observational studies, and regulatory reports to evaluate the main limitations of nirsevimab and maternal RSV vaccination. Literature searches were conducted in major databases, focusing on efficacy, safety, immunogenicity, implementation, and population-specific challenges. Results: Both nirsevimab and maternal vaccination provide strong protection during the first six months of life, but their effectiveness wanes thereafter. This is concerning as nearly half of RSV-related deaths occur in children over six months old. Maternal vaccine efficacy is uncertain in very-preterm infants, and safety concerns persist, including potential associations with preterm birth, Guillain–Barré syndrome, and hypertensive disorders. Real-world data from low-income countries are lacking, limiting generalizability. Additionally, the risk of vaccine-associated enhanced disease (VAED), although unconfirmed, has delayed pediatric vaccine development. Emerging monoclonal antibodies and live-attenuated vaccines are under investigation to extend protection beyond infancy. Conclusions: Despite substantial progress, current RSV prevention strategies leave critical gaps, particularly for older infants and underserved populations. There is a pressing need for next-generation vaccines, enhanced pharmacovigilance, and equitable global implementation to ensure sustained and inclusive RSV protection. Full article

An $MAP/PH/N$-type queuing system functioning within a finite-state Markovian random environment is studied. The random environment’s state impacts the number of available servers, the underlying processes of customer arrivals and service, and the impatience rate of customers. The impact on the state space of the underlying processes of customer arrivals and of the more general, as compared to exponential, service time distribution defines the novelty of the model. The behavior of the system is described by a multidimensional Markov chain that belongs to the classes of the level-independent quasi-birth-and-death processes or asymptotically quasi-Toeplitz Markov chains, depending on whether or not the customers are absolutely patient in all states of the random environment or are impatient in at least one state of the random environment. Using the tools of the corresponding processes or chains, a stationary analysis of the system is implemented. In particular, it is shown that the system is always ergodic if customers are impatient in at least one state of the random environment. Expressions for the computation of the basic performance measures of the system are presented. Examples of their computation for the system with three states of the random environment are presented as 3-D surfaces. The results can be useful for the analysis of a variety of real-world systems with parameters that may randomly change during system operation. In particular, they can be used for optimally matching the number of active servers and the bandwidth used by the transmission channels to the current rate of arrivals, and vice versa. Full article

Background/Objectives: The under-five mortality rate (U5MR) remains a serious health challenge in Indonesia, with low birth weight (LBW) being a key risk factor. This study aimed to identify predictors of survival among under-five children with LBW using data from the 2017 Indonesia Demographic and Health Survey (IDHS). Methods: This cross-sectional study included 625 children under five with LBW. The dependent variable was under-five mortality (children aged 0–59 months), while the independent variables include child (gender), maternal (age at delivery, education, empowerment, delivery complications, and breastfeeding history), health service (antenatal care-ANC and place of delivery), and household (wealth quintile and residence) factors. Data were obtained from the 2017 IDHS using household and women’s questionnaires and analyzed using univariate analysis, Kaplan–Meier estimation, and Cox regression. Results: 41 of 625 children born with LBW died before the age of five. The Kaplan–Meier estimation found that maternal (delivery complications and breastfeeding history), health service (ANC history and place of delivery), and household factors (residence) significantly influenced the survival of LBW children. The Cox regression results showed that LBW children who were breastfeed and whose mother had adequate antenatal care visits had a lower risk of under-five mortality. Surprisingly, children born in health facilities had a significantly higher risk of death compared to those born elsewhere. Conclusions: Exclusive breastfeeding, adequate antenatal care, and place of delivery are important determinants of survival among children born with LBW. This support targeted interventions to improve the survival chances of children born with LBW, particularly in their early years of life. Full article

Neonatal jaundice (NNJ) is a leading cause of death in the early neonatal period, disproportionately affecting newborns in sub-Saharan Africa. In a setting without access to rapid assessment via transcutaneous bilirubin meter, we sought to determine how closely the diagnosis and treatment of neonatal jaundice at an urban district hospital aligned with retrospective assessment and treatment recommendations using the BiliApp (based on the UK NICE Guideline CG98). This retrospective chart review study aimed to identify: (1) What percent of admissions within 8 days of birth to the Mother and Baby Unit (MBU) at our study site were admitted for a primary diagnosis of neonatal jaundice, and what characterized those admissions? (2) How did treatment provided compare to the recommendations of the United Kingdom NICE Guideline CG98 via the “BiliApp”? and (3) Among those with jaundice, what factors were associated with an increased likelihood of severity indicative of the need for blood exchange therapy? The charts of all neonates admitted to the MBU at Suntreso Government Hospital (SGH), in Kumasi, Ghana, in 2020 were reviewed by trained research assistants. Data were collected regarding demographics, reason for admission, diagnostic markers (e.g., serum bilirubin level), treatments performed in the hospital, and outcome. Data were analyzed using Stata 18.0. There were 1059 newborns admitted to the MBU in 2020 at less than 8 days of age. A total of 179 (16.9%) were admitted with a primary diagnosis of neonatal jaundice. According to the BiliApp, 29.4% (n = 50) of newborns admitted for jaundice had bilirubin levels that were normal or below the phototherapy threshold for their gestational age on admission; 25.3% (n = 43) were at or near the threshold for phototherapy; 21.2% (n = 36) were above the phototherapy threshold; and 24.1% (n = 41) were above the blood exchange therapy threshold. The BiliApp recommended no treatment for 21.2% (n = 36) of newborns, repeated assessment for 33.6% (n = 57), phototherapy for 21.2% (n = 36), and exchange therapy for 24.1% (n = 41). By comparison, 8.2% (n = 14) of neonates admitted for jaundice received no treatment, 77.8% (n = 133) received phototherapy only, and 14.0% (n = 24) received both phototherapy and exchange therapy. Without sufficient data on G6PD status and parent/newborn blood type to include in the analysis, the biggest risk factors for a BiliApp recommendation of exchange therapy included serum bilirubin level (OR 1.01, p < 0.001) and gestational age (OR 0.51, p < 0.001), even after controlling for breastfeeding and male sex of the newborn. Without access to rapid assessment tools, many providers in low-resource settings are put in a position to presumptively treat newborns suspected of having jaundice, rather than waiting for serum lab tests to return. Given the cost of transcutaneous bilirubin meters, additional options for rapid diagnostic testing are warranted. Full article

Markov chain perturbation theory is a rapidly developing subfield of the theory of stochastic processes. This review outlines emerging applications of this theory in the analysis of stochastic models of chemical reactions, with a particular focus on biochemistry and molecular biology. We begin by discussing the general problem of approximate modeling in stochastic chemical kinetics. We then briefly review some essential mathematical results pertaining to perturbation bounds for continuous-time Markov chains, emphasizing the relationship between robustness under perturbations and the rate of exponential convergence to the stationary distribution. We illustrate the use of these results to analyze stochastic models of biochemical reactions by providing concrete examples. Particular attention is given to fundamental problems related to approximation accuracy in model reduction. These include the partial thermodynamic limit, the irreversible-reaction limit, parametric uncertainty analysis, and model reduction for linear reaction networks. We conclude by discussing generalizations and future developments of these methodologies, such as the need for time-inhomogeneous Markov models. Full article