Efficacy and safety of withholding antimicrobial therapy in children with cancer, fever and neutropenia, with a demonstrated viral respiratory infection: a randomized clinical trial.

OBJECTIVES: To validate the efficacy and safety of withholding antimicrobial therapy in a new cohort of children with cancer and febrile neutropenia (FN) having a demonstrated viral respiratory tract infection (RTI). METHODS: Prospective, multicenter, non-inferiority, randomized study, approved by the ethical committee, in children presenting with FN at seven hospitals in Chile, evaluated at admission for diagnosis of bacterial and viral pathogens. Children who were positive for a respiratory virus (RV), negative for a bacterial pathogen and had a favorable evolution after 48-72 hours of antimicrobial therapy were randomized to either maintain or withhold antimicrobial therapy. The primary endpoint was the percentage of episodes with uneventful resolution, whereas the secondary endpoints were days of fever/hospitalization, requirement of antimicrobial treatment readministration, sepsis, pediatric intensive care unit (PICU) admission and death. RESULTS: A total of 301 of 939 children with FN episodes recruited between March 2021 and December 2023 had a RV as a unique identified microorganism, of which 139 had a favorable evolution at 48-72 hours and were randomized, 70 to maintain and 69 to withdraw antimicrobial therapy. The median days of antimicrobial therapy was 5 (IQR 3-6) versus 3 (IQR 3-6) days (p<0.001), with similar frequency of uneventful resolution (66/70 (94%) and 66/69 (96%), RR 1.01, (95% CI 0.93-1.09), absolute risk difference 0.01, (95% CI -0.05-0.08) and similar number of days of fever and days of hospitalization. No cases of sepsis, PICU admission or death were reported. CONCLUSIONS: We validated the strategy of withdrawal antimicrobial therapy in children with FN and viral RTI, based on clinical and microbiological/molecular diagnostic criteria. This will enable advances in antimicrobial stewardship strategies with a possible future impact on antimicrobial resistance.

Divergent Gut Microbiota: Archaeal and Bacterial Signatures Unveil Unique Patterns in Colombian Cyclists Compared to Weightlifters and Non-Athletes.

Engagement in physical activity, across various sports, promotes a diverse microbiota in active individuals. This study examines the gut microbiota of Colombian athletes, specifically weightlifters (n = 16) and road cyclists (n = 13), compared to non-athletes (n = 15). Using Kruskal-Wallis tests, the physical activity level of a group of non-athletic individuals and the sports experience of a group of professional athletes is analyzed. The median age of participants is 24 years, comprising 25 men and 19 women. The microbiota is collected using fecal samples. Participants provided these samples during their pre-competitive stage, specifically during the concentration phase occurring two weeks prior to national competitions. This timing is chosen to capture the microbial composition during a period of heightened physical preparation. Questionnaire responses and microbial composition assessments identify disparities among groups. Microbial composition analysis explores core microbiome, abundance, and taxonomy using Pavian, MicrobiomeAnalyst 2.0, and GraPhlAn. ANCOM-BC2 reveals differentially abundant species. Road cyclists exhibit decreased Bacteria and increased Archaea abundance. Phylum-level variations included Planctomycetes, Acidobacteria, and Proteobacteria, while Bacteroidetes prevailed. Key families influencing gut microbiota are Bacteroidaceae, Muribaculaceae, and Selenomonadaceae. Weightlifters exhibit unique viral and archaeal community connections, while cyclists showed specialized microbial interplay influenced by endurance exercise. Correlation network analysis emphasizes distinctive microbial interactions within athlete groups, shedding light on the impact of physical activities on gut microbiota and athlete health.

Exploring the utility of Geometric Morphometrics to analyse prehistoric hand stencils.

Hand stencils are a remarkable graphic expression in Prehistoric rock art, dating back to 42 ka BP. Although these stencils provide direct impressions of the artists' hands, the characterization of their biological profile (i.e., biological sex and age) is very challenging. Previous studies have attempted this analysis with traditional morphometrics (TM), whereas little research has been undertaken using Geometric Morphometrics (GM), a method widely used in other disciplines but only tentatively employed in rock art studies. However, the large variation in relative finger position in archaeological hands poses the question of whether these representations can be examined through GM, or, in contrast, if this creates an unmanageable error in the results. To address this issue, a 2D hand scans sample of 70 living individuals (F = 35; M = 35) has been collected in three standardized positions (n = 210) and digitized with 32 2D conventional landmarks. Results show that the intra-individual distance (mean Procrustes distance between Pos. 1-2 = 0.132; 2-3 = 0.191; 1-3 = 0.292) is larger than the inter-individual distance (mean in 1 = 0.122; 2 = 0.142; 3 = 0.165). Finally, it has been demonstrated that the relative finger positions, as well as the inclusion of all hand parts in the analysis, have an overshadowing effect on other variables potentially involved in the morphometric variability of the hand, such as biological sex.

Modulating redox properties of solid-state ion-conducting materials using microwave irradiation.

The industrial adoption of low-carbon technologies and renewable electricity requires novel tools for electrifying unitary steps and efficient energy storage, such as the catalytic synthesis of valuable chemical carriers. The recently-discovered use of microwaves as an effective reducing agent of solid materials provides a novel framework to improve this chemical-conversion route, thanks to promoting oxygen-vacancy formation and O2-surface exchange at low temperatures. However, many efforts are still required to boost the redox properties and process efficiency. Here, we scrutinise the dynamics and the physicochemical dependencies governing microwave-induced redox transformations on solid-state ion-conducting materials. The reduction is triggered upon a material-dependent induction temperature, leading to a characteristically abrupt rise in electric conductivity. This work reveals that the released O2 yield strongly depends on the material's composition and can be tuned by controlling the gas-environment composition and the intensity of the microwave power. The reduction effect prevails at the grain surface level and, thus, amplifies for fine-grained materials, and this is ascribed to limitations in oxygen-vacancy diffusion across the grain compared to a microwave-enhanced surface evacuation. The precise cyclability and stability of the redox process will enable multiple applications like gas depuration, energy storage, or hydrogen generation in several industrial applications.

Estimating 225Ac yield in thorium metal targets.

In this work we estimate the yield of the radioisotope [Formula: see text] in a thorium metal target geometry similar to that described by Roberston et al.. We do so in three different yet complimentary studies. In the first study, we pose a three-way coupled time-dependent model describing beam position, temperature field, and local growth of the activity of the radioisotope and solve this numerically. In the second study, we present an analytical solution of the model equations for a generalized solid target in the "beam-thin" limit, i.e. where only a small fraction of the incoming energy of the proton beam is deposited into the thorium material. In the third study, we use the insight gained from the analytical solution and describe an operating strategy to maximize yield by modulating the beam flux temporally.

Parada cardiorrespiratoria intrahospitalaria: incidencia, factores pronósticos y resultados / In-hospital cardiac arrest: incidence, prognostic factors and results

Introducción y objetivos: La parada cardiorrespiratoria (PCR) intrahospitalaria es una entidad clínica con elevada morbimortalidad que presentan hasta el 2% de los pacientes ingresados. La PCR supone un importante problema de salud pública a nivel económico, social y sanitario, susceptible de revisión y mejora. El objetivo de este estudio es determinar su incidencia, la recuperación de la circulación espontánea (RCE) y la supervivencia en el Hospital de la Princesa, así como las características clínicas y demográficas de los pacientes que la sufren. Material y métodos: Estudio observacional, retrospectivo, descriptivo, de tipo registro de casos, durante un periodo de 12 meses, de pacientes por los que se avisó por PCR al equipo de intervención rápida (EIR) compuesto por el servicio de Anestesiología y Reanimación. Resultados: Un total de 44 pacientes fueron incluidos en el estudio, de los cuales 22 (50%) eran mujeres. La edad media fue de 75,70 años (±15,78 años). La incidencia obtenida fue de 2,88 PCR por cada 100.000 ingresos hospitalarios; 22 (50%) pacientes consiguieron la RCE y 11 (25%) obtuvieron la supervivencia al alta hospitalaria. La comorbilidad más prevalente en los pacientes con PCR fue la hipertensión arterial (63,64%). No fueron presenciadas el 66,7% de las PCR y solo el 15,9% presentaron un ritmo desfibrilable. Conclusiones: Los resultados obtenidos son similares a los presentados en otros grandes estudios. Por esta razón, recomendamos implementar EIR y dedicar tiempo a la formación del personal hospitalario en torno a la PCR.(AU)

Background and aims: In-hospital cardiac arrest (CA) is a clinical entity with high morbidity and mortality that occurs in up to 2% of hospitalized patients. It is a public health problem with important economic, social, and medical repercussions, and as such its incidence needs to be reviewed and improved. The aim of this study was to determine the incidence of in-hospital CA, return of spontaneous circulation (ROSC), and survival rates at Hospital de la Princesa, and to define the clinical and demographic characteristics of patients with in-hospital CA. Material and methods: Retrospective observational chart review of patients presenting in-hospital CA and treated by anaesthesiologists from the hospital's rapid intervention team. Data were collected over 1 year. Results: Forty-four patients were included in the study, of which 22 (50%) were women. Mean age was 75.70 years (±15.78 years), and incidence of in-hospital CA was 2.88 per 100,000 hospital admissions. Twenty-two patients (50%) achieved ROSC and 11 patients (25%) survived until discharge home. The most prevalent comorbidity was arterial hypertension (63.64%); 66.7% of cases were not witnessed, and only 15.9% presented a shockable rhythm. Conclusions: These results are similar to those reported in other larger studies. We recommend introducing immediate intervention teams and devoting time to training hospital staff in in-hospital CA.(AU)

Resident physician duty hours, resting times and European Working Time Directive compliance in Spain: a cross-sectional study.

BACKGROUND: There is a growing interest in understanding the impact of duty hours and resting times on training outcomes and the well-being of resident physicians. However, to this date no state-wide analysis exists in any European country. OBJECTIVES: Our aim is to describe the shift work scheduling and to detail the degree of compliance with the Spanish legislation and the European Working Time Directive (EWTD) of Spanish resident physicians, focusing on territorial and specialty distribution. MATERIAL AND METHODS: A descriptive cross-sectional analytical study was designed through an online survey adapted from the existing literature. RESULTS: Out of the 2035 surveyed resident physicians undergoing PGT in Spain, 80.49% exceeded the 48 h per week limit set by the EWTD and 13% of them did not rest after a 24-h on-call shift. The mean number of on-call shifts in the last 3 months was 15.03, with the highest mean reported in Asturias, La Rioja, and Extremadura. 51.6% of respondents had a day-off after a Saturday on-call shift. Significant differences are observed by region and type of specialty. CONCLUSION: Resident physicians in Spain greatly exceed the established 48 h/week EWTD limit. Likewise, non-compliance with labor regulations regarding mandatory rest after on-call duty and minimum weekly rest periods are observed.

Cerebral amyloid angiopathy-related inflammation: clinical features and treatment response in a case series.

INTRODUCTION: Cerebral amyloid angiopathy-related inflammation (CAA-ri) is an entity characterised by an inflammatory response to ß-amyloid deposition in the walls of cerebral microvessels. METHODS: We conducted a retrospective review of a series of patients with a diagnosis of CAA-ri according to histopathological study findings or clinical-radiological diagnostic criteria. RESULTS: The study included 7 patients (5 men) with a mean age of 79 years. Disease onset was acute or subacute in 6 patients. The most frequent symptoms were cognitive impairment (n = 6), behavioural alterations (n = 5), epileptic seizures (n = 5), focal neurological signs (n = 4), and headache (n = 2). Cerebrospinal fluid was abnormal in 3 patients (lymphocytic pleocytosis and high protein levels). The most frequent MRI findings were microbleeds (n = 7), subcortical white matter hyperintensities on T2-FLAIR sequences (n = 7), and leptomeningeal enhancement (n = 6). Lesions were bilateral in 3 patients and most frequently involved the parieto-occipital region (n = 5). Amyloid PET studies were performed in 2 patients, one of whom showed pathological findings. Two patients underwent brain biopsy, which confirmed diagnosis. All patients received immunosuppressive therapy. An initially favourable clinical-radiological response was observed in all cases, with 2 patients presenting radiological recurrence after treatment withdrawal, with a subsequent improvement after treatment was resumed. CONCLUSIONS: Early diagnosis of CAA-ri is essential: early treatment has been shown to improve prognosis and reduce the risk of recurrence. Although a histopathological study is needed to confirm diagnosis, clinical-radiological criteria enable diagnosis without biopsy.

Programa piloto de cribado de riesgo cardiovascular en la mujer perimenopáusica desde la farmacia comunitaria: proyecto ‘MENOVASC’ / Pilot programme for screening perimenopausal women for cardiovascular risk from community pharmacy: MENOVASC Project

Introducción: desde hace más de 20 años, las enfermedades cardiovasculares constituyen la primera causa de muerte en el mundo. Generalmente, son poco usuales en las mujeres premenopáusicas debido a la protección cardiovascular de los estrógenos endógenos, por lo que tradicionalmente se ha subestimado el riesgo cardiovascular en estas.Objetivos: realizar un cribado de riesgo vascular en mujeres perimenopáusicas desde la farmacia comunitaria.Material y métodos: estudio descriptivo a partir de una muestra oportunista en una farmacia comunitaria de mujeres entre 45 y 55 años. Previa cita se les tomó los niveles de colesterol y tensión arterial, peso y altura. Se recopiló información sobre factores de riesgo cardiovasculares mayores y específicos de la mujer, medicación que tomaban, actividad física y tabaquismo. Con estos datos se estimó su riesgo cardiovascular mediante tablas SCORE. Resultados: se recogieron 18 formularios, con una edad media de las demandantes de 49 (DE 3) años. El 38,9 % (IC95 %: 17,3 a 64,3) presentaba hipertensión arterial y el 44,4 % (IC95 %: 21,5 a 69,2) presentaba niveles de colesterol iguales o superiores a 190 mg/ml. Todas las participantes tenían al menos un factor de riesgo mayor o específico de la mujer.Conclusiones: Se constata la utilidad del cribado de riesgo vascular en mujeres perimenopáusicas. Todo ello pone en valor la intervención del farmacéutico comunitario en la detección y gestión de factores de riesgo cardiovascular. (AU)

Mapping absorbency in cellulosic fibres with iron tracers.

Understanding water absorbency in paper is challenging as fibre swelling and out-of-plane deformation occur simultaneously during liquid imbibition. Liquid absorption is commonly accessed by gravimetric tests, which provides limited information on the local spatial and temporal distribution of fluid in the substrate. In this work, we developed iron tracers to map liquid imbibition in paper by in situ precipitation of iron oxide nanoparticles during passage of the wetting front. The iron oxide tracers were found to be robustly attached to the cellulosic fibres. After liquid absorption tests, absorbency was investigated by mapping the distribution of iron in 3D using X-ray micro-computed tomography (µCT) and in 2D using energy-dispersive X-ray spectroscopy. We demonstrate a difference in tracer distribution between the wetting front and the fully saturated region supporting that imbibition proceeds in two phases, i.e. liquid percolation through the cell wall initially prior to filling of the external pore spaces. Critically, we demonstrate that these iron tracers enhance image contrast and allow for new imaging modalities in µCT for fibre networks.

Modelling interventions and contact networks to reduce the spread of carbapenem-resistant organisms between individuals in the ICU.

BACKGROUND: Contact precautions are widely used to prevent the transmission of carbapenem-resistant organisms (CROs) in hospital wards. However, evidence for their effectiveness in natural hospital environments is limited. OBJECTIVE: To determine which contact precautions, healthcare worker (HCW)-patient interactions, and patient and ward characteristics are associated with greater risk of CRO infection or colonization. DESIGN, SETTING AND PARTICIPANTS: CRO clinical and surveillance cultures from two high-acuity wards were assessed through probabilistic modelling to characterize a susceptible patient's risk of CRO infection or colonization during a ward stay. User- and time-stamped electronic health records were used to build HCW-mediated contact networks between patients. Probabilistic models were adjusted for patient (e.g. antibiotic administration) and ward (e.g. hand hygiene compliance, environmental cleaning) characteristics. The effects of risk factors were assessed by adjusted odds ratio (aOR) and 95% Bayesian credible intervals (CrI). EXPOSURES: The degree of interaction with CRO-positive patients, stratified by whether CRO-positive patients were on contact precautions. MAIN OUTCOMES AND MEASURES: The prevalence of CROs and number of new carriers (i.e. incident CRO aquisition). RESULTS: Among 2193 ward visits, 126 (5.8%) patients became colonized or infected with CROs. Susceptible patients had 4.8 daily interactions with CRO-positive individuals on contact precautions (vs 1.9 interactions with those not on contact precautions). The use of contact precautions for CRO-positive patients was associated with a reduced rate (7.4 vs 93.5 per 1000 patient-days at risk) and odds (aOR 0.03, 95% CrI 0.01-0.17) of CRO acquisition among susceptible patients, resulting in an estimated absolute risk reduction of 9.0% (95% CrI 7.6-9.2%). Also, carbapenem administration to susceptible patients was associated with increased odds of CRO acquisition (aOR 2.38, 95% CrI 1.70-3.29). CONCLUSIONS AND RELEVANCE: In this population-based cohort study, the use of contact precautions for patients colonized or infected with CROs was associated with lower risk of CRO acquisition among susceptible patients, even after adjusting for antibiotic exposure. Further studies that include organism genotyping are needed to confirm these findings.

[Lecanemab in Alzheimer's disease: are we really before a shift in the prognosis of the disease?] / Lecanemab en la enfermedad de Alzheimer: ¿realmente estamos ante un cambio en el pronóstico de la enfermedad?

TITLE: Lecanemab en la enfermedad de Alzheimer: ¿realmente estamos ante un cambio en el pronóstico de la enfermedad?

Characterization of a unique polysaccharide monooxygenase from the plant pathogen Magnaporthe oryzae.

Blast disease in cereal plants is caused by the fungus Magnaporthe oryzae and accounts for a significant loss in food crops. At the outset of infection, expression of a putative polysaccharide monooxygenase (MoPMO9A) is increased. MoPMO9A contains a catalytic domain predicted to act on cellulose and a carbohydrate-binding domain that binds chitin. A sequence similarity network of the MoPMO9A family AA9 showed that 220 of the 223 sequences in the MoPMO9A-containing cluster of sequences have a conserved unannotated region with no assigned function. Expression and purification of the full length and two MoPMO9A truncations, one containing the catalytic domain and the domain of unknown function (DUF) and one with only the catalytic domain, were carried out. In contrast to other AA9 polysaccharide monooxygenases (PMOs), MoPMO9A is not active on cellulose but showed activity on cereal-derived mixed (1→3, 1→4)-ß-D-glucans (MBG). Moreover, the DUF is required for activity. MoPMO9A exhibits activity consistent with C4 oxidation of the polysaccharide and can utilize either oxygen or hydrogen peroxide as a cosubstrate. It contains a predicted 3-dimensional fold characteristic of other PMOs. The DUF is predicted to form a coiled-coil with six absolutely conserved cysteines acting as a zipper between the two α-helices. MoPMO9A substrate specificity and domain architecture are different from previously characterized AA9 PMOs. The results, including a gene ontology analysis, support a role for MoPMO9A in MBG degradation during plant infection. Consistent with this analysis, deletion of MoPMO9A results in reduced pathogenicity.

Modified Anterior Z Le Fort III Osteotomy.

Introduction: Surgery of the midface for non-syndromic patients with maxillo-malar hypoplasia exclusively has had many breakthroughs lately. The surgical techniques for midface surgery are varied and must be selected according to the patient's problem. Purpose: The technique is a modification of the Z Osteotomy, the Modified Anterior Z Le Fort III Osteotomy (MAZLFIIIO), is used to correct posteroanterior midface deficiency of 6 mm at most. It can be combined simultaneously with a Le Fort I osteotomy if a greater maxillary advance is needed. MAZLFIIIO advances midface without grafts or distraction osteogenesis. The anterior reposition of the midface is calculated in millimetres and depends on the relation of the eye's most inferior point, as well as the orbital's hard and soft tissues. It is a predictable osteotomy, only for patients without vertical excess of the midface. The osteotomy planned is drawn over a stereolithographic model, and then Z-shaped surgical splints are fabricated over it. Transverse midface deficiencies of no more than 4 mm can also be corrected during the malar osteotomy. A great number of patients are operated exclusively with Le Fort I osteotomies, leaving behind an undesirable step between the upper part of the midface and the Le Fort I osteotomy. Methods: The Modified anterior Z Le Fort III Osteotomy (MAZLFIIIO) was performed in seven patients, from 2016 to 2018. Results: The results obtained with the proposed osteotomy notably improve the appearance of the patient and provide a better protection of the lower part of the eye, while widening the maxillary sinus. Conclusion: We consider that maxillo-malar hypoplasias are very common; the surgeon pretends not to give importance to the deformity, exclusively using an advance Le Fort type osteotomy, with both functional and aesthetic treatment being limited. In this article, we give all the elements to perform this Le Fort III Modified Osteotomy in anterior Z, and that it is a combined and routine procedure in midface surgery.

Cellulose Nanocrystal Gels with Tunable Mechanical Properties from Hybrid Thermal Strategies.

Gels are useful materials for drug delivery, wound dressings, tissue engineering, and 3D printing. These various applications require gels with different mechanical properties that can be easily tuned, also preferably excluding the use of chemical additives, which can be toxic or harmful to the body or environment. Here, we report a novel strategy to synthesize cellulose nanocrystal (CNC) gels with tunable mechanical properties. Sequential freeze-thaw cycling and hydrothermal treatments were applied to CNC suspensions in different orders to give a series of pristine CNC hydrogels. Freeze-drying of the hydrogels also afforded a series of lightweight CNC aerogels. The mechanical properties of the hydrogels and aerogels were studied by rheological measurements and compression strength tests, respectively. Specifically, the complex modulus of CNC hydrogels ranged from 160 to 32,000 Pa among eight different hydrogels, while Young's modulus of CNC aerogels was tuned from 0.114 to 3.98 MPa across five different aerogels. The microstructures of aerogels were also investigated by scanning electron microscopy and X-ray microtomography, which revealed remarkable differences between the materials. Solvent sorption-desorption tests showed that the reinforced networks have excellent stability over the basic CNC aerogels in ethanol, demonstrating a material enhancement from the preparation strategies we developed. Thermal conductivity and thermal stability for these materials were also investigated, and it was found that the lowest thermal conductivity was 0.030 W/m K, and all of the aerogels are generally stable below 280 °C. These characteristics also expand the potential applications of this family of CNC gels to lightweight supporting materials and thermal insulators.

Monte Carlo N-Particle forward modeling for density reconstruction of double shell capsule radiographs.

In the Double Shell Inertial Confinement Fusion concept, characterizing the shape asymmetry of imploding metal shells is vital for understanding energy-efficient compression and radiative losses of the thermonuclear fuel. The Monte Carlo N-Particle MCNP® code forward models radiography of Double Shell capsule implosions using the Advanced Radiographic Capability at the National Ignition Facility. A procedure is developed for using MCNP to reconstruct density profiles from the radiograph image intensity. For a given Double Shell imploding target geometry, MCNP radiographs predict image contrast, which can help guide experimental design. In future work, the calculated MCNP synthetic radiographs will be compared with experimental radiographs to determine the radial and azimuthal density profiles of the Double Shell capsules.

Characterization of a 1D-imaging high-energy x-ray backlighter driven by the National Ignition Facility Advanced Radiographic Capability laser.

Plastic deformation of samples compressed to Mbar pressures at high strain rates at the National Ignition Facility (NIF) forms the basis of ongoing material strength experiments in conditions relevant to meteor impacts, geophysics, armor development, and inertial confinement fusion. Hard x-ray radiography is the primary means of measuring the evolution of these samples, typically employing a slit-collimated high-Z microdot driven by the NIF laser to generate >40 keV x rays [E. Gumbrell et al., Rev. Sci. Instrum. 89, 10G118 (2018) and C. M. Huntington et al., Rev. Sci. Instrum. 89, 10G121 (2018)]. Alternatively, a dysprosium "micro-flag" target driven by the Advanced Radiographic Capability laser (∼2 kJ, 10 ps) can deliver significantly higher spatiotemporal resolution [M. P. Hill et al., Rev. Sci. Instrum. 92, 033535 (2021)], especially in high-opacity samples. Initial experiments revealed problematic brightness and spectral gradients from this source, but by radiographing a set of diamond-turned, 105 µm-thick Pb test objects and supported by simulations using the 3D Monte Carlo code GEANT4, these geometry-dependent gradients across the field of view are quantified and mitigation strategies are assessed. In addition to significantly enhancing the modulation transfer function compared to the existing system, image stacking from multiple layers of image plate is shown to almost double the signal to noise ratio that will reduce uncertainties in future dynamic strength experiments.

Basal Extended Mentoplasty.

Introduction: The chin is one of the most visible facial structures. Chin surgery, was initially described, for, the treatment of facial abnormalities, advancing the mandibular symphysis; achieved anterior displacement of the base of the tongue showing some value in the treatment of snoring and obstructive sleep apnea, and achieved adequate lip competence. We designed the Basal Extended Mentoplasty (BEM) based on the needs of patients orthodontically compensated, but dissatisfied with the appearance of his face as well as upper airway problems looking for a solution to this, design and planning the advances of the chin. Materials and Methods: Patients operated in the service of Maxillofacial Surgery, Specialist Hospital, "Dr. Bernardo Sepulveda "XXI Century National Medical Center, during the period of 2015-2019, orthodontically compensated patients, with labial incompetence and Class II skeletal. Sixty-five patients were operated during this period, and eight cases are presented. Results: Lip competition, osseointegration of the segments is observed, with a proper projection of the lower third, no nerve or vascular damage in the area. Conclusions: The design of the osteotomy is for orthodontically compensated patients with labial incompetence and Class II skeletal, giving a result mandibular lengthening. The BEM achieved adequate lip competence demonstrated by an interlabial gap of 0 mm, achieved adequate osseous consolidation of the fracture site with a more harmonious facial balance and profile, without nerve or vascular damage with spectacular results.

Factors affecting the radon (222Rn) emanation from aquifer rock materials: Implications for radiological and groundwater tracer studies.

Groundwater discharge (GD) is an important component of the water budget in large urban areas with high water demands. Radon is a routinely used groundwater tracer in mass-balances for evaluating GD to surface water bodies. The diffusion of 222Rn from aquifers' sediments parameter is important for GD's assessments. Sediment equilibration experiments were employed with various sediment and rock materials, including sand, granite, gneiss and loess that constitute the Pampeano Aquifer (PA) in the Buenos Aires Province, Argentina. These experiments allowed the 222Rn concentration determination in pore fluids at secular equilibrium and to examine the factors affecting the magnitude of radon 222Rn emanation from the materials under study. We found that radon emanation decreases in a power function (R2 = 0.9, n = 6) with the particle size of the tested PA sediment and rock materials. Based on our results, loess sediments with the smallest particle size and the largest particle surface area have the highest radon emanation. This strongly suggests that these two parameters are the parameters that govern the radon diffusive fluxes' magnitude in the PA. On the other hand, we found that PA basement rocks, primarily granite and gneiss, showed an exhalation rate of radon of 8.1 ± 0.81 Bq∙m-2∙h-1 and 13.2 ± 1.32 Bq∙m-2∙h-1. These rates are two orders of magnitude higher than loess sediments (0.3 ± 0.1 Bq∙m-2∙h-1), owning to the higher natural content of radon's parent isotopes from the 238U natural decay series. These high radon levels are consistent with currently available radon concentrations measured in groundwater in contact with the PA basement rock formations. This study demonstrates the importance of considering site-specific aquifer properties in the radon diffusive fluxes when utilizing radon as a groundwater tracer in hydrological studies. This is the first quantitative study that examines the aquifer characteristics affecting radon emanations in this large hydrogeological system.