Massless field equations are fundamental in particle physics. In Clifford analysis, the Euclidean version of these equations has been dealt with but it is not clear, even in dimension 4, what should be the right analogue of massless field equations for fields with values in a general irreducible Spin(4)-module. The main aim of the paper is to explain that a good possibility is to take the so-called generalized Cauchy-Riemann equations proposed a long time ago by E. Stein and G. Weiss. For this choice of the equations, we show that their polynomial solutions form different irreducible Spin(4)-modules. This is an important step in developing the corrresponding function theory.

To understand the transmission dynamics of diarrhea in random environment, in this paper we propose a stochastically perturbed dysentery diarrhoea epidemic model with controls. Using the theory of stopping time, we first show the existence of global positive solution of the model. Then, we study the stochastic dynamics of the model and present a stochastic threshold $\mathcal{R}_0^S$ which determines the extinction and persistence of the disease. Based on Khasminskii’s theory, we further prove that the model has a unique ergodic stationary distribution under the condition of $\mathcal{R}_0^S>1$. Numerical simulations are carried out to verify the analytical results, showing that the white noise, and the constant treatment and sanitation may have certain inhibitory effects on disease transmission. Lastly, the model is further extended to include colored noise and seasonal fluctuation to study the long-term transmission dynamics of disease. It is found that the method proposed in this paper is universal.

The error assessment is made on the classical Grey Model (GM(1,1)) and the variants of Grey Lotka-Volterra dynamical system namely the Grey Lotka-Volterra Model (GLVM), the Fractional Grey Lotka-Volterra Model (FGLVM) and the Variable-order Fractional Grey Lotka-Volterra Model (VFGLVM) for modeling the transaction counts of three selected cryptocurrencies in 2-and 3-dimensional framework. Bitcoin, Litecoin and Ripple. The cryptocurrencies of interest are Bitcoin, Litecoin and Ripple. The 2-dimensional models use Bitcoin and Litecoin transactions from April, 28, 2013 to February, 10, 2018. The 3-dimensional model uses transactions of Bitcoin, Litecoin and Ripple from August, 7, 2013 to February, 10, 2018. The error sequence patterns and the the Mean Absolute Percentage Error (MAPE) suggest a relatively higher accuracy of the VFLVM in 2- and 3-dimensional study.

Understanding the microbial linkages among the soils, plants and animals is crucial for maintaining the balance of an ecosystem in grazed grasslands. However, previous studies always focused on the biotopes of soil, phyllosphere and faeces separately and little has been known about the microbial distribution and migration among these biotopes. In this study, a systematic survey to investigate the overlap and differentiation among the various microbiotas of biotopes and how the environmental filter on microorganisms served for the ecosystem was conducted at the molecular level. Our findings revealed the biotopes' role of biofilter leads to the discrepancy of microbiota distribution among the soil, phyllosphere and faeces. The substantial overlaps between soil and phyllosphere in fungi, bacteria and archaea indicated that soil could potentially perform as the microbial reservoir for phyllosphere. However, there was only fungal mass migration running through the ecosystem to link all the biotopes while there are little communal OTUs of bacteria and archaea. These findings promoted our understanding of the biotope contribution to microbial migration and improved the knowledge of microbial linkages in the grazed grassland ecosystem.

Despite the growing number of recent studies on genome-wide divergence during speciation, the genetic basis and mechanisms of genomic divergence and speciation are still incompletely understood. In most species, natural selection plays a key role in genomic heterogeneous divergence. Additionally, barriers to gene flow, such as chromosomal rearrangements or gene incompatibilities, can also cause genome heterogeneity and speciation. Based on whole genome re-sequencing data from 27 Populus alba and 28 P. adenopoda individuals, we explored the reasons for the heterogeneous differentiation of genomes of these two closely related species. The results showed that the two species diverged ~5-10 million years ago (Mya), when the Qinghai-Tibet Plateau reached a certain height and the inland climate of the Asian continent became arid, which caused the two species begin to diverge and eventually led to speciation. In highly differentiated regions, neutrality tests (Tajima’s D and Fay & Wu’s H) of these regions revealed no difference while the absolute divergence (dxy) were significantly higher than genome background, which indicates that barriers to gene flow rather than natural selection played a major role in maintaining genomic heterogeneous divergence and reproductive isolation, which is the most important condition for speciation. We further found that some genes related to reproduction may be involved in explaining the reproductive isolation of the two species.

Aims: This study aims to analyze the novel Coronavirus disease (COVID-19) related testicular pain in hospitalized patients due to COVID-19 and to review as an etiological factor for epididymitis, orchitis or both. Methods: A total of 91 patients were included in the study. A questionnaire was formed for the questioning of testicular pain or epididymo-orchitis in patients with COVID-19. Demophrahics and past medical history was also recorded. Patients’ neutrophil and lymphocyte counts, neutrophil-lymphocyte ratios (NLR), C-reactive protein (CRP) levels and D-dimer values were recorded. Patients with COVID-19 were divided into two groups according to absence or presence of testicular pain or epididymo-orchitis as group 1 and group 2. All results were compared for both groups. Results: The median age of patients was similar in both groups. Testicular pain was occured in 10.98% of the patients. Clinical presentation of epididymo-orchitis was diagnosed in only one patient. No statistically significant difference was reported in terms of patients’ age, levels of CRP and D-Dimer or NLR and results of questionnaire form queries between the two groups (p>0.05). Conclusion: Testicular pain was observed more frequently in hospitalized COVID-19 cases. While no inflammation marker which is related to predict of testicular pain or epididymo-orchitis was found in patients with COVID-19.

“RNA + peptide editing are two successive independent mechanisms needed in order to make a panoply of new functional isoforms in a variety of binding protein families”. I present the specificities of ‘Chemosensory Proteins’ CSPs in insects and argue about their potential role in life origins and evolution. In particular, I address the relatedness of the observed mutations in insect CSPs to the origin of life. I describe the observed mutations in these CSPs in several insect species are occuring via various mechanisms, RNA editing and/or during protein synthesis, and propose that such mechanism could have been important in the emergence and evolution of life on the Earth’s crust.

1. Pachycrepoideus vindemiae and Trichopria drosophilae are cosmopolitan pupal parasitoids of Drosophilidae that attack the invasive Drosophila suzukii. This study investigated one aspect of their phenotypic plasticity – host acceptance and offspring fitness on 25 Drosophila species in a phylogenetic framework. Each parasitoid’s key biological and ecological traits were compared among the different host species. 2. Results demonstrate that both parasitoids successfully parasitized and developed from all tested host species. Although the parasitoids’ efficiency and offspring fitness varied among host species, effects on life-history characteristics or ecological traits appeared to be unrelated to the phylogenetic position of tested host species. 3. Both parasitoids benefited from attacking larger hosts, with body size of emerging progeny positively correlated to host size and an increased fecundity (mature egg load) of female wasps. Achieving larger body size came at no significant costs in immature development time. 4. The results show remarkable levels of phenotypic plasticity in the parasitoids’ body growth and development, which is discussed with respect to their potential for host range expansion.

Introduction: Clinical reasoning is a crucial competence for medical practice and also a complex task that is susceptible to cognitive errors. It is usually taught based on whole clinical cases, from a practical rather than from a conceptual perspective. Addressing the need to improve clinical reasoning teaching into undergraduate medical curricula, it was hypothesized that medical students could benefit from a practice and theoretical approach to the clinical reasoning process. Methods: A four week online course, based on simulation and groupal reflective practice was developed, to promote metacognition between the participants. The course was delivered to 8 sixth year medical students as an elective module. A questionnaire consistent of four open-ended questions was designed to explore knowledge about clinical reasoning and cognitive errors, and was applied at the beginning and at the end of the course. A qualitative analysis was conducted with Berelson content analysis method. Results: After the course the students changed their understanding about clinical reasoning, considering it more like a process and identifying the dual nature described in modern theories of clinical decision making. Also they changed their knowledge about cognitive errors, attributing them not only to lack of knowledge, and understanding that they can actively practice some strategies to reduce cognitive bias. Discussion: This study confirmed that undergraduate students change in a positive way their concept of clinical reasoning and their knowledge about this cognitive process and cognitive errors that occur on it after a course that includes simulation and reflection.

IntroductionLoss of smell is a common complaint in adults and yet has been underestimated. Anosmia, complete loss of smell, is thought to affect at least 1-5% of the population[1]. Based on European estimates, anosmia is more prevalent than profound hearing loss or blindness in the UK. Causes for olfactory loss are varied but the main diagnostic groups include sinonasal disease (62%) and post-infectious olfactory dysfunction (PIOD) (11%)[2]. Olfactory dysfunction has now emerged as a key symptom in the coronavirus pandemic and it is possible we may see a cohort of patients with lasting problems following the peak of the Covid-19 impact[3, 4]. Historically, there is wide variation in clinical practice reported by clinicians to patients on prognosis or treatment[5]. Guidelines for the overall management of olfactory disorders now exist in the Position Paper on Olfactory Dysfunction[6] and recently the British Rhinological Society has produced a consensus statement on managing Covid-related PIOD[7] but the impact of those guidelines have yet to penetrate routine clinical practice.Previously published data has shown the high impact on quality of life experienced by olfactory disorder patients, including depression, anxiety, impairment of eating experience, feelings of isolation and relationship difficulties[8, 9]. Most patients suffer a loss of flavour perception which can adversely affect their appetite, but this can be made even worse when parosmia is also present. Given the number of potential treatment options for PIOD that have been proposed but yet to undergo formal evaluation through a randomised clinical trial[10], there is a pressing need to deliver more RCTs in this area. A recent German study has highlighted Vitamin A as a potential therapeutic agent for further evaluation[11]. In anticipation of setting up a clinical trial to evaluate the role of vitamin A intranasally for PIOD we sought to generate evidence of need to funders through Public and Patient Involvement (PPI) in partnership with the charity Fifth Sense that represents patients affected by Smell & Taste disorders in the UK (www.fifthsense.org.uk).The aim of this study was to characterise the experience of patients with PIOD in terms of the treatment they received in order to demonstrate any unmet need.

Purpose: Dissemination of generic drug (GD) use could provide significant savings on drug expenditures and contribute to the long-term sustainability of healthcare. We aimed to exhibit the nationwide trend of GD use in primary care and investigate potentially relevant drug and patient factors. Methods: We analyzed all electronic prescriptions registered to national Prescription Information System by primary care physicians in Turkey during 2013-2016. We determined GD share in quantity and cost for each year. We further analyzed GD use in terms of patients’ demographic characteristics, most commonly prescribed preparations, and frequent indications. Results: In the four-year period, we identified 518,335,821 prescriptions, where GDs constituted 54.0% (n=786,972,813) with a total cost share of 36.9-37.8%. GD use was highest in 2016 (54.4%) and lowest in 2014 (53.6%). In each year, GD prescribing was higher in women (53.7-54.7%) than men (53.4-54.1%, p<0.001). GD utilization decreased as the age group increased, which was 64.0-64.5% in <18-year-old group and 46.0-47.1% in ≥75-year-old group. Among the top ten encountered indications, highest and lowest GD prescribing was detected in acute tonsillitis (68.1%) and hypertension (33.9). Metformin had the highest percentage of GD prescribing (96.1-97.7%) whereas esomeprazole showed the lowest GD prescribing (4.5-14.8%) among the most frequently used preparations in primary care. Conclusions: This study shows a modest upward trend of GD utilization in primary care, though its share appears as lower than expected. GDs were less likely to be prescribed in older age groups and seem as more pronounced in acute conditions, particularly infectious diseases.

Here we report the binding site (We call it as drug target) of the COVID-19 main protease 3CLpro 6LU7 using Full Electronic Structure Calculation of Quantum Mechanics. The protease 6LU7 has 18038 elecrons , we need to calculate its wave funciton (it is called the molecular orbitor in the chemistry field) and energy level for this huge elecronic system. Then according to three rules to obtain the exact active pocket, active resudes, even active atoms of 6LU7. Finally put active pocket and all candidate small-molecule drugs or peptides group into an artificial intelligence deep learning 3D-CNN program to calculate the binding affinity. The result is that the pocket3 with three active atoms CE3, CZ3 and CH2 of 6LU7 is real design target for small-molecule drugs and the drug Tipranavir is located on the first position with binding affinity about 5.4. Our calculations show that the binding affinity of Remdesivir with 3CLpro 6LU7 is very small, less than 0.5. This just shows that Remdevivir (GS-5734) is the first channel. Because Remdesivir is not a nucleotide analog, it is a prodrug of nucleotide analogs, it has many protective groups around it. When the drug enters the body, these atomic groups will act as enzymes in the cell It is broken down, leaving the active drug and though the drug N3 company with 6LU7, but its binding affinity is only about 4.2, so it could not be a real drug for 6LU7. The quantum mechanics calculation give out such accurate drug target. We have to take up pocket 3 to design inhibitor drug. The drug screening is only the first step in the long and costly pharmaceutical process, but we prove that it can be completely calculation by quantum mechanics. Hopefully, this method can provide an effective and rapid screening method for finding new coronavirus drugs.

This paper examined the use of lethal force by law enforcement against people brandishing knives in the United States. The purpose of the research was to better understand the correlates of lethal force encounters and inform the development and implementation of systems and procedures designed to monitor, predict, and reduce the frequency of fatal police/civilian violence. There are two parts to this mixed-methods study: a quantitative analysis of the distribution of fatal event factors and descriptive epidemiology of fatal police encounters among persons brandishing knives. A non-probability sample (n = 174) was assembled from publicly reported use-of-force fatalities. The analysis revealed the typical decedent was a mentally ill 37-year-old White male brandishing a kitchen knife. Most encounters involved 2–4 officers firing 2–4 bullets at a person no more than 10-feet away. Police injuries, while uncommon, tended to be moderate, but none were fatal. Contrary to previous studies, Thursday was the most lethal day of the week. California accounted for 29% of all fatal encounters. Future research is needed to examine Black decedents' over-representation, explore the unexpectedly high number of deaths in California, and evaluate trends over time.  

Several studies have already shown that coronary angiography and PCI can be safely performed after CABG. It is of paramount importance that early graft failure is recognized in a timely manner and that an appropriate treatment is delivered immediately in order to reduce the extent of myocardial damage and improve clinical outcome. Therefore, urgent angiography allows both identification of the underlying cause of early graft failure and immediate treatment according to the findings. So far, recent evidence shows that PCI to native coronary arteries is associated with higher procedural success rate and less complications leading to the better clinical outcome.  

Background: Patients with variable symptoms suggestive of asthma but with normal forced expiratory volume in 1 second (FEV1) often fail to be diagnosed without a bronchial provocation test, but the test is expensive, time-consuming, risky and not readily available in all clinical settings. Methods: A cross-sectional study was performed in 692 patients with FEV1≥80% predicted; normal neutrophils and chest high-resolution computed tomography; and recurrent dyspnea, cough, wheeze, and chest tightness. Results: Compared with subjects negative for BHR (n=522), subjects positive for BHR (n=170) showed increased FENO values, EOS, and R5-R20; decreased FEV1, FEV1/Forced vital capacity (FVC), and forced expiratory flow (FEFs) (P≤.001 for all). Small-airway dysfunction was identified in 104 BHR+ patients (61.17%), and 132 BHR- patients (25.29%) (P<.001). The areas under the curve (AUCs) of variables used singly for a BHR diagnosis were lower than 0.77. Using joint models of FEF50%, FEF75%, or FEF25%-75% with FENO increased the AUCs to 0.845, 0.824, and 0.844, respectively, significantly higher than univariate AUCs (P <.001 for all). Patients who reported chest tightness (n=75) had lower FEFs than patients who did not (P<.001 for all). In subjects with chest tightness, the combination of FEF50% or FEF25%-75% with EOS also increased the AUCs substantially, to 0.815 and 0.816, respectively (P <.001 for all versus the univariate AUCs). Conclusion: FENO combined with FEF50% and FEF25%-75% predict BHR in patients with normal FEV1. FEF25%-75%. FEF50%, or FEF25%-75% together with EOS also can potentially suggest asthma in patients with chest tightness.

In order to analyze the action mechanism of the tunnel support structure and its supporting characteristics in a layered and weak rock tunnel, an experimental study on seven types of support situations, namely, rough tunnel, systematic rock bolt support, systematic rock bolt, and shotcrete support, systematic rock bolt and shotcrete and steel arch support, steel pipe support, steel pipe, and shotcrete support, and steel pipe and shotcrete and steel arch support, has been conducted. The mechanical, deformation, and support characteristics of the rock with holes under uniaxial compression tests have been studied. The experimental results demonstrated that (1) all different support structures can enhance the uniaxial compressive strength of the specimens, but different support structures exhibit different effects. The rock bolt can significantly enhance the strength of the specimen, but the supporting effect of concrete and steel arches is not evident. (2) The bedding direction directly affects the strength enhancement of the support structure to the specimen, the support strength of the support structure to the rock with a bedding angle of 90° is higher than that of the rock with a stratification angle of 0°, and the bedding affects the failure process of the rock mass and the secondary crack distribution. (3) By using the CT scan of the specimens after the test, it is found that the bolt’s crack arrest effect on cracks is the result of weakening, shearing, and arresting of cracks in the anchorage zone; the crack arrest effect is related to the size of the anchorage zone, and the larger the range of the anchorage zone, the better the crack arrest effect.

Background: The SQ tree SLIT-tablet has recently been approved for treatment of tree pollen allergy. Health care workers should be provided with detailed safety data for clinical use. Objective: To assess the tolerability and safety of the SQ tree SLIT-tablet in adults and adolescents. Methods: Safety data were pooled from two phase-II and one phase-III double-blinded, randomized, placebo-controlled trials including adults and adolescents with allergic rhinitis and/or conjunctivitis treated before and during one pollen season once-daily with the SQ tree SLIT-tablet (12 SQ-Bet) or placebo. Results: The most frequently reported IMP-related AEs with 12 SQ-Bet were oral pruritis (39% of subjects) and throat irritation (29%). IMP-related AEs were mainly mild or moderate in severity, and the majority resolved without treatment and did not lead to treatment interruption/discontinuation. With 12 SQ-Bet, oral pruritus was more frequent among PFS subjects (45%) than in subjects without PFS (29%). A greater proportion of PFS subjects interrupted treatment (19%) than subjects without PFS (7%). The 12 SQ-Bet did not seem to induce an increased risk of asthma: 7 events were reported in 7 subjects with 12 SQ-Bet and 11 in 10 subjects with placebo. No differences were seen in the risk of moderate to severe IMP-related AEs regardless of age, PFS status and asthma medical history. Conclusions: The 12 SQ tree SLIT-tablet was well tolerated in tree pollen allergic subjects with no major safety concerns detected. This safety profile supports daily at-home sublingual administration once the first dose is tolerated when administered under medical supervision.

The influence of the hole surface integrity on the fatigue life of 2024-T351 aluminium drilled parts was investigated. Fatigue tests were conducted on open-hole specimens and a large campaign was carried out to characterize the hole surface integrity (roughness measurements, hardness measurements, metallographic observations and residual stress analysis). An innovative technique, the Hole Opening Comparative Technique, was set up in order to analyse the residual stress state of the parts. In this study, strain hardening of the hole subsurface seems to be the main factor influencing the fatigue behaviour, associated with a residual stress state of the part.

Soil and water conservation measures, especially reforestation and check dam construction, have been progressively implemented on the coarse sandy hilly catchment region of the Yellow River basin for several decades, and climate conditions are also dynamic. Therefore, it is very urgent to understand how the precipitation variation, land use changes and check dams affect soil erosion and sediment yield in a large watershed. The sediment delivery distributed (SEDD) model was employed to quantitatively identify the impacts of the three factors on soil erosion and sediment yield in the Kuye River watershed. Significant land use changes, with the conversion of arable land and bare land to vegetation cover and construction land, occurred in the study watershed from 1987 to 2016. In addition, 306 key dams were built in the watershed, with a total storage capacity of 316.64 Mm3, according to the statistical data of 2011. Hot spot analysis showed that the high-risk regions for soil erosion and sediment yield were mainly concentrated in the middle reaches of the watershed. The simulation results showed that the check dams were the dominant factor, reducing total sediment load by 53.77% in 2006. However, from 1987 to 2016, the contribution of these three factors (precipitation variation, land use changes and check dams) to sediment reduction was 29.10%, 40.09% and 30.81%, respectively, which indicated that all of them had significant influence on sediment load. The results can serve as a reference for watershed management and policy implementation.

Background: Treating Hodgkin lymphoma (HL) among children comprises a trade-off between cure and reduction of radiotherapy (RT) toxicity. Fluorodeoxyglucose positron emission tomography combined with computed tomography (PET/CT) identifies patients showing early favorable response to chemotherapy, and therefore can preclude the RT need. Objective: The current study aims to discuss the prognostic value of interim PET/CT following two cycles of chemotherapy OEPA (Oncovin, Etoposide, Prednisone, Adriamycin) in pediatric HL in terms of event-free survival (EFS) and overall survival (OS). Materials and Methods: We retrospectively included all HL patients younger than 18 years, between January 2010 and December 2017. Interim PET/CT was performed after two chemotherapy cycles. Patients were stratified into three risk groups into: group 1, group 2 and group 3. OEPA regimen was used in early disease while Cyclophosphamide, Oncovin, Prednisone and Dacarbazine were added in advanced disease. RT was avoided in all patients who achieved complete response (CR) by interim PET/CT. Results: 65 patients were included. Based on the negative interim PET/CT responses, 43 (66.1%) patients were treated without RT. The 5-year EFS for the entire cohort was 89 % and OS was 97%. Most of the PET/CT scans at the end of treatment were done in positive interim PET/CT cases, while in early responders; only CT scans were done. Conclusions: Interim PET/CT in pediatric HL is a good prognostic tool to evaluate early responders after the 2 initial chemotherapy cycles and hence omit RT to this group of patients.

Neste texto, vamos tratar do postulado que tem a interpretação da conservação do momento linear de um sistema de partículas isolado. Veremos como este postulado dá origem à segunda e à terceira leis de Newton.

Headwater forest ecosystems of the western U.S. generate a large portion of the dissolved organic matter (DOM) transported across North America. Land cover changes that alter forest structure and forest species composition affect the quantity and composition of DOM transferred to aquatic ecosystems. Clear-cut harvesting effects ~1% of the forest area of North America annually, leaving most forests in varying stages of successional regrowth, and the total area of old-growth forest decreasing. The consequences of this widespread management practice on watershed carbon cycling remain unknown. We investigated the role of land cover change from old-growth subalpine forest to lodgepole pine dominated second-growth on the character and reactivity of DOM hillslope exports. We evaluated inputs of DOM from litter leachates and export of DOM collected at the base of trenched hillslopes during a three-year period (2016-2018) at the Fraser Experimental Forest in northcentral Colorado, USA. Dissolved organic carbon (DOC) and total dissolved nitrogen (TDN) were higher in lateral subsurface flow draining old- versus secondary-growth forest. Fluorescence spectroscopy showed that the DOM exported from the old-growth forest was more heterogeneous and aromatic and that proteinaceous, microbially processed DOM components were more prevalent in the second-growth forest. Biological oxygen demand (BOD) assays revealed much lower microbial metabolism of both DOM inputs from litter leachate and subsurface exports from old-growth forest. Old-growth and second-growth forests are co-mingled in managed ecosystems, and our findings demonstrate that the influence of species composition on DOM inputs can affect the reactivity of DOM transferred from terrestrial to aquatic ecosystems.

Our understanding of the mechanisms routing precipitation inputs to evapotranspiration and streamflow in catchments is still very fragmented, particularly in the case of saturated flows. Here we explore five mechanisms by which plants and streams compete with each other for water, based on multiple scales of observations in a flat semiarid sedimentary catchment of central Argentina subject to abrupt hydrological transformations. Since the 80s, the “El Morro” catchment (1334 km2, -33.64°, -65.36°) experienced a fast expansion of crops over native forests and grasslands, rapid water table level rises (~0.3 m y-1), spontaneous expansion of wetlands and permanent streams by groundwater sapping. Based on episodic and continuous groundwater level, stream flow, and remote sensing data we show that plants not only take away water from streams by drying the unsaturated zone (mechanism 1), but by tapping the saturated zone in the expanding waterlogged environments (mechanism 2) and in the upland environments that remain uncultivated and display increasing tree cover (mechanism 3). Conversely, streams take away water from plants through pulsed bed-deepening and water table depression (mechanism 4), and riparian and wetland zones burying with fresh sediments (mechanism 5). While earlier work established widespread support for mechanisms 1 preventing stream formation, diurnal and seasonal fluctuations of water table levels and base streamflow records in this study proved the importance of mechanisms 2 and 3 under the current high-water table conditions. These data together with remotely-sensed greenness showed a growing but localized relevance of mechanism 4 and 5 as the stream network developed. The distinction of recharge- vs. topography-controlled groundwater systems is useful to organize the interplay of these concurrent mechanisms. Findings point to the unsaturated-saturated contact zone as a crucial and dynamic hub for water partition and for ecological, geomorphological, and hydrological knowledge integration.

We describe our use of intracardiac echocardiography (ICE) to guide endomyocardial biopsy of the left ventricle in a patient with chronic heart failure secondary to endocardial fibroelastosis. Under ICE guidance, we advanced the bioptome through the middle of the mitral annulus, within a trans-septal sheath, and guided the bioptome to the correct location on the mid-posterior wall of the left ventricle. This was performed without adverse events, such as injury to the chordae tendineae or mitral valve regurgitation. Therefore, ICE-guidance is possible for left-sided heart procedures and could lower the risk of complications and improve the biopsy rate for diagnosis.