Myelofibrosis (MF) in the pediatric setting is uncommon and appears to be pathogenically heterogeneous. MF due to intrinsic bone marrow abnormality (IMF) is distinct from adult-type Primary myelofibrosis (PMF) as they can lack the common genetic markers of clonality. To date, all but two reported patients with pediatric MF and mutated MPIG6B have been Arabic, and all reported cases have had a family history of consanguinity. Here we report the first North American patient of European ancestry with pediatric MF in whom novel compound heterozygous mutations of MPIG6B were identified.

A document by Xue-Xian Zhang. Click on the document to view its contents.

In this work, stationary states in nonequilibrium plasmas of chemical reactions that can produce hydrogen are explored, namely the water splitting and water gas shift reactions. For both reactions, the effluent from the reactor at long gas residence times in the plasma was found to be independent of the influent speciation. In other words, feeding the reactor either 0.1 H2O or 0.1H2+0.05O2 by mole produced the same effluent composition, and similarly, feeding the reactor 0.1CO+0.1H2O produced nominally the same effluent as 0.1CO2+0.1H2. For both reactions, the effluent from the plasma was found to be very far from local equilibrium at the total pressure and background temperature of the reactor. An important conclusion of this work is that special attention must be paid to the recombination zone in plasma chemical processes. The recombination zone tends to drive the gas composition from plasma stationary states back towards local equilibrium.

This study explores an understanding of human-wildlife conflict (HWC) focused on tiger, particularly the status and trend of human-tiger conflict (HTC), in three major areas of Chitwan National Park (CNP); Ayodhyapuri, Patihani and Meghauli VDCs. A set of questionnaire survey was conducted in 98 households [Ayodhyapuri (38), Patihani (30) and Meghauli (30)]. Additionally, key informant interviews were conducted and official records of CNP, National Trust for Nature Conservation (NTNC) and Department of National Park and Wildlife Conservation (DNPWC) during month of June- July, 2017 were referred. Records from 2003 to 2015 at CNP shows that highest HTC was recorded in the year 2003-2004 (235 cases), out of which human casualties were 22 (4 injured and 18 killed). The trend has declined thereafter with the lowest conflict recorded in the year 2013-2014 (17 cases), out of which human casualties were 6 (4 injured and 2 killed). A significantly higher human-tiger interaction was recorded in Ayodhypuri compared to other two study sites (χ2 = 7.88; d.f. = 2; p = 0.02). However, a contradictory trend was obtained based on our survey owing to the long compensation procedure (51.02%), less compensation (30.61%) and weak information flow (18.36%). Besides, the development of dense community forest lured the tigers to the nearby buffer zone causing conflicts with tigers. Nevertheless, the perception of respondent relative to tiger conservation was found to be positive. Conservation education, awareness programs along with adequate and prompt compensation against damages coupled with regular/timely monitoring of tigers may help to reduce human-tiger conflicts. Keywords: Human-tiger conflict; Compensation; Livestock depredation; Retaliation

One of the most effective defenses of avian hosts against obligate brood parasites is the ejection of parasitic eggs from the nests. Despite the clear fitness benefits of this behavior, individuals within so-called “egg rejecter” host species still show substantial variation in their propensity to eliminate foreign eggs from the nest. We argue that this variation can be further understood by studying the physiological mechanisms of host responses to brood parasitic egg stimuli: independent lines of research increasingly support the hypothesis that stress-related physiological response to parasitic eggs may trigger egg rejection. The “stress-mediated egg rejection” hypothesis requires that hosts activate the stress-response when responding to parasitic eggs. We tested this prediction by experimentally parasitizing incubating American robins Turdus migratorius, an egg rejecter host to obligate brood parasitic brown-headed cowbirds Molothrus ater, with mimetic or non-mimetic model eggs. To assess the stress response, we measured the heart rate in incubating females immediately after experimental parasitism. We also measured plasma corticosterone and, in a subset of birds, used RNA-sequencing to analyze the expression of proopiomelanocortin (POMC), a precursor of adrenocorticotropic hormone (ACTH), two hours after experimental parasitism. We found that egg type had no effect on heart rate. Two hours following experimental parasitism, plasma corticosterone did not differ between the differently colored model egg treatments or between rejecter and accepter females within the non-mimetic treatment. However, females exposed to non-mimetic eggs showed an upregulation of POMC gene expression in the pituitary compared to females treated with mimetic eggs. Our findings suggest that parasitic eggs may activate the stress-related hypothalamic-pituitary-adrenal axis in an egg-rejecter host species, although the dynamics of this response are not yet understood.

The chromosomal rearrangement 2La has been directly involved in the ecological and deadly epidemiological success of the malaria mosquitoes Anopheles gambiae and Anopheles coluzzii in sub-Saharan Africa. However, little is known about the biological and ecological factors that drive the local and temporal dynamics of this inversion in both species. Here, we performed a year-round longitudinal survey in Bangui, Central African Republic. We monthly sampled An. gambiae and An. coluzzii mosquitoes indoor and outdoor using human landing catches for 48 hours non-stop. We molecularly karyotyped all specimens to study the 2La inversion frequency variations, and monitored the mosquito spatial and temporal biting behavior throughout the year. In total, we successfully karyotyped 5121 An. gambiae and 986 An. coluzzii specimens. The 2La inversion frequency was higher in An. coluzzii than in An. gambiae across the year. In An. gambiae and An. coluzzii, the inversion frequency or karyotypes did not influence the biting behavior, either location or time. Moreover, the inversion frequency variation in both species was also independent of local climatic changes. Overall, our results revealed that in Bangui, the 2La inversion segregates at different frequency in each species, but this is not influenced by their trophic behavior. Studying the impact of urban settings and the population genetic structure of these two An. gambiae complex members could bring insights into the intrinsic relationship between 2La inversion and local conditions. More studies are needed to understand the polymorphic equilibrium of this inversion in Bangui.

Background Ventricular tachycardia (VT) and ventricular fibrillation are the most causes of early death in patients with myocardial infarction (MI). This study was aimed to explore whether LRP6 and its upstream genes circRNA1615 and miR-152-3p modulated the phosphorylation of Connexin-43 (Cx43) via Gαs in VT of MI. Method we constructed the hypoxia cardiomyocyte model and AMI mice, and explored the modulation relationship of LRP6 and its upstream genes circRNA1615 and miR-152-3p. In addition, the immunoblot analysis with monoclonal and polyclonal antibodies were used to detect whether LRP6 and Cx43 were phosphorylated, further investigated that the LRP6 regulated the phosphorylation of its downstream target Cx43 via G-protein alpha subunit Gαs by using cell transfection, FISH assay, HE staining, RTqPCR, and Western blot techniques. Result LRP6 mRNA expression was significantly reduced in AMI group compared with the control group. Hypoxia could inhibit the protein and phosphorylation levels of LRP6 and Cx43. The expression of circRNA1615 in AMI mice was significantly decreased, but overexpression of circRNA1615 significantly reversed the inhibitory effect of AMI. Also overexpression of circRNA1615 could weaken the effect of miR-152-3p mimic, and the miR-152-3p mimic increased the hypoxia injury of LRP6 and Cx43, further LRP6 interference fragments could aggravate hypoxia injury of Cx43. The overexpression of LRP6 could significantly increase the protein level and phosphorylation level of Cx43, but the interference with LRP6 showed the opposite trend. Noticeably, the interference with Gαs weakened the protein and phosphorylation levels of Cx43, however, the interference with LRP6 and Gαs further inhibited the protein and phosphorylation levels of Cx43. Finally, the transcriptions of circRNA1615 and LRP6 were inhibited in AMI, but the transcription of miR-152-3p was promoted, and the overexpression of circRNA1615 could weaken the damage effect and VT of AMI. Conclusion LRP6 and its upstream genes circRNA1615 and miR-152-3p modulated the phosphorylation of Cx43 via Gαs in VT of MI.

Hydrogen is not only a promising energy, but also widely used in inflammation treatment and sports training. The key to these applications is to obtain purity hydrogen conveniently. Water electrolysis provides a green and sustainable method for hydrogen production, but the urgent problem is to develop low-cost and efficient electrocatalysts. In this work, hierarchically porous Ni3S2 nanostructures, which the flocculent two-dimensional Ni3S2 is coated on the surface of Ni3S2 nanosheets, were successfully grown on nickel foam through a facile two-step hydrothermal reaction. The hierarchically porous Ni3S2 nanostructures has a large specific surface area can expose more active sites and facilitates desorption of bubbles. Moreover, the theoretical calculation indicated that the dimensional confinement effect of metallic Ni3S2 improves the carrier concentration and conductivity. Therefore, the hierarchically porous Ni3S2 nanostructures on nickel foam exhibited enhanced hydrogen evolution reaction and good catalytic stability. This work sheds some light on improving the catalytic performance of metallic compounds.

Introduction Cardioneuroablation (CNA) is a technique used to modulate cardiac parasympathetic tone in patients with sino-atrial (SA) and atrio-ventricular (AV) vagally mediated syncope. We describe the case of a patient who developed AV block after a first procedure of CNA, requiring a second procedure. Case presentation A 47-Year-old man presented with recurrent syncope (daily episodes) associated with high vagal tone conditions. An ECG monitoring showed frequent episodes of sinus bradycardia and sinus arrest, with pauses up to 17 seconds. AV node conduction impairment was never identified. A CNA procedure targeting the right superior and posterior ganglionated plexi (GPs), both from the left and right atrium, was performed with acute success. The subsequent night, repetitive episodes of AV block with normal sinus rate were observed. A second procedure was performed targeting the posteromedial left GP. Follow-up at 4 months showed no recurrent syncopal event and no bradyarrhythmia episode on the implantable loop recorder. Conclusion This case report demonstrates that ablation limited to the right superior and posterior GPs may not be enough for neurocardiogenic syncope and a more systematic approach, extending the ablation to the posteromedial left GP, should be considered.

Background: The health sector is one of the outstanding performers through remarkable digitalization in health. Maternal and Perinatal Death Surveillance and Response (MPDSR) was implemented in Bangladesh to investigate the causes of maternal and perinatal deaths in community and health facilities. Objectives: The purpose was to explore information systems available to assess the MPDSR program status, the planning process, gaps and barriers and actions developed using real-time information. Data Collection and Analysis: This study included both primary and secondary data analysis. Six key informant interviews and MPDSR action plans were reviewed from seven districts. Secondary collected from 27 districts. Results: This study revealed that the government health information systems could notify 62% of the maternal deaths and 29% of the neonatal deaths. Despite the challenges in data quality, the health managers developed action plans. The death and service data showed positive changes in most of the districts despite COVID 19 pandemic. Information systems like the MPDSR dashboard and RMNCAH scorecard could is used as tools to assess the impact of actions in a real-time manner. Major gaps are weak monitoring, non-functional MPDSR committees and incoordination, IT issues, blaming culture, and lack of capacity in analyzing data. Conclusion: The outcome of the MPDSR program depends upon how the data is converted to action and measuring the impact. Innovative data visualization tools like health dashboards, scorecards, and administrative data can play a pivotal role in measuring and evidence-based planning. The major challenge remains with capturing all deaths and weak data analysis capacity.

Objective: To explore the views of female genital mutilation (FGM) survivors, men, and healthcare professionals (HCPs) on the timing of deinfibulation surgery and NHS service provision. Design: Qualitative study informed by the sound of silence framework. Setting: Survivors and men were recruited from three FGM prevalent areas of England. HCPs and stakeholders were from across the UK. Sample: 44 survivors, 13 men and 44 HCPs. 10 participants at two community workshops and 30 stakeholders at a national workshop. Methods: Hybrid framework analysis of 101 interviews and three workshops. Results: There was no consensus across groups on the optimal timing of deinfibulation for survivors who wished to be deinfibulated. Within group, survivors expressed a preference for deinfibulation pre-pregnancy and HCPs antenatal deinfibulation. There was no consensus for men. Participants reported that deinfibulation should take place in a hospital setting and be undertaken by a suitable HCP. Decision making around deinfibulation was complex but for those who underwent surgery it helped to mitigate FGM impacts. Whilst there were examples of good practice, in general, FGM service provision was sub-optimal. Conclusion: Deinfibulation services need to be widely advertised. Information should highlight that the procedure can be carried out at different time points, according to preference, and in a hospital by suitable HCPs. Future services should ideally be developed with survivors, to ensure that they are clinically and culturally appropriate. Guidelines would benefit from being updated to reflect the needs of survivors and to ensure consistency in provision. Study registration number ISRCTN 14710507

Objective To compare long-term survival outcomes between laparoscopic radical hysterectomy (LRH) and open radical hysterectomy (ORH) in early-stage cervical adenocarcinoma under the new FIGO 2018 staging guideline. Design Retrospective study Setting and population Early-stage cervical adenocarcinoma received LRH and ORH; 47 Chinese hospitals. Methods We matched patients with early-stage cervical adenocarcinoma in the new FIGO 2018 staging guideline with known risk factors for recurrence who underwent ORH and LRH. Main Outcome Measures 5-year overall survival and 5-year disease-free survival rates Results In total, 549 patients were enrolled in our study, including 235 patients in LRH group and 314 in ORH group. After matching some factors that may affect the prognosis, each group had 223 patients. There was no difference in DFS between LRH and ORH in risk-adjusted analysis (HR1.258, 95% CI: 0.507-3.125, P=0.621). There was no difference in OS between LRH and ORH in risk-adjusted analysis (HR1.961, 95% CI: 0.536-7.183, P=0.309). LRH resulted in significantly lower estimated blood loss (361.2 versus 165.3 ml, P < 0.001) and shorter postoperative anal exhaust time (2.8 versus 2.5 days, P = 0.003) . Intraoperative complication ( 2.7% versus 5.8%，P=0.101) and postoperative complication ( 5.8% versus 6.3%, P=0.843) rates were similar in the two groups. Conclusions LRH has comparable survival outcomes with ORH and was associated with earlier recovery in early-stage adenocarcinoma of the uterine cervix. LRH may be an appropriate option for early-stage cervical adenocarcinoma compared with ORH.

Early T cell precursor acute lymphoblastic leukemia is a relatively new, high risk subgroup of acute lymphoblastic leukemia characterized by unique immune-phenotype and disease biology. ETP ALL cells share similarities with hematopoietic stem cells and myeloid progenitor cells. These patients have lower rates of complete remission overall survival. Venetoclax is an orally bioavailable BCL 2 inhibitor. We report the treatment outcomes of 2 patients with ETP ALL who achieved MRD negative remission with short course of venetoclax.

Objectives: This study aimed to evaluate the early and rapid diagnostic value and the cut-off value of Heart-type fatty acid-binding protein (H-FABP) for the perioperative myocardial infarction (PMI) diagnosis after off-pump coronary artery bypass grafting (OPCABG) surgery. Method: 109 patients scheduled for first-time, elective, and isolated OPCABG surgery were erolled in this single-center, prospective and consecutive study. Serial samples for measurement of H-FABP at pre-anesthesia induction (T0, baseline), completion of last distal anastomosis (T1), on ICU admission (T2), and at 2h (T3), 4h (T4), 8h (T5), 24h (T6), and 48h (T7) were taken to analyze for H-FABP. CK-MB and cTnI were taken at T4, T5, T6, and T7. Patients were first divided into three groups according to the level of cTnI and ECG changes within the early 24 hours. Results: 44 patients served as a control group, 52 patients identified as myocardial injury group, and 13 patients defined as myocardial infarction group. The level of H-FABP released was significantly higher in the myocardial infarction group than another two groups. Using a cut-off value of 20.53 ng/ml for H-FABP, the sensitivity was 84.62%, 92.31%, and 76.92% immediately, 2 hours, and 4 hours after entering the ICU. The sensitivity of combined H-FABP and cTnI was 92.31% and 84.62% at 4 and 8 hours after entering the ICU. Conclusions: With an optimal H-FABP cut-off level of 20.53 ng/ml, H-FABP was the early and reliable biomarker for PMI diagnosis after OPCABG.

Background Despite substantial literature that addresses preoperative anxiety, identifying effective anxiety-management interventions is still recommended. Identifying factors related to preoperative anxiety is essential for intervention planning. Aim To explore patient-reported factors contributing to decreased anxiety among patients scheduled for coronary artery by-pass grafting (CABG). Methods This mixed-methods observational study involved 75 patients aged 40-83 (70.7% men; mean age 65.4±9.41). Qualitative analysis involved 25 randomly selected patients (focus group) and asked to specify factors they believed were helpful in reducing their anxiety. Visual Analogue Scale (VAS-Anxiety) was used at the moment of diagnosis and decision making (Time1, retrospectively), and on the day preceding CABG (Time2). Focus group responses were explored with the use of Interpretative Phenomenological Analysis (IPA). The Pearson’s chi -squared and the Mann-Whitney-U tests were calculated to explore differences between the study groups. Significance level α≤0.05 was used in all analyses. Results VAS-Anxiety scores reduced from 5 points at Time1 to 3 points at Time 2 (p<0.01). Fifty patients (66.7%) reported decreased anxiety between Time1 and Time2, 21 (28%) reported a stable level and 4 (5.3%) reported an increase. Employment status was the only significant factor differentiating “relief’ and “no relief” groups among socio-demographic and clinical variables. IPA yielded five main themes: conversations with health care providers, perceived inevitability of surgery, family support, other patients’ experience, and religion/faith. Conclusions Individual patient-centered interview in conjunction with emotional support are vital for managing preoperative anxiety. Providing contact with family members and paying attention to spiritual needs are also important.

t’s time for a fivesome. Commentary to: “The predictive value of five glomerular filtration rate formulas for long-term mortality in patients undergoing coronary artery bypass grafting” Coronary artery disease is an extremely common condition and coronary artery bypass-grafting is still one of the most important therapeutic strategy to treat it. Chronic kidney disease is often affecting patients with CAD. Nevertheless, the literature is still debating what formula estimate the best the glomerular filtration rate in patients undergoing CABG. Indeed, the formulas used in clinical practice have some differences some are more accurate in patients with diabetes, while there are some bias given by age and body mass index. In cardiac surgery, the choice of the most fitting formula to evaluate GFR has important clinical implication and, up to now, three formulas have been compared at most. Eilon Ram et al. present a retrospective study which compares the 5 most used formulas (CG, MDRD, CKD-EPI, Mayo, and IB) to derive GFR to evaluate the one with the best accuracy in predicting long-term mortality. In order to do so, they divided 3744 patients in three groups according to the estimated GFR by means of all 5 formulas: significant CKD according to all formulas, non-significant CKD according to all formulas and discordant results (meaning that at least one formula gave normal GFR and at least one formula gave abnormal GFR). Patients with the highest mortality were the ones with significant CKD according to all formulas.

Title : Submitral Aneurysm: Exploring a Rare PathologyAuthors : Kellen Round BS1, Jake L. Rosen BA1, Colin C. Yost BA1, T. Sloane Guy MD, MBA21Sidney Kimmel Medical College, Thomas Jefferson University, 1025 Walnut St #100, Philadelphia, PA 191072Division of Cardiac Surgery, Department of Surgery, Thomas Jefferson University, Curtis Bldg, Ste 620, 1015 Walnut St Philadelphia, PA 19107Running Title: Submitral Aneurysm Commentary

A document by David Sanders . Click on the document to view its contents.

Insects are the most speciose group of animals and play a central role in ecosystem processes and functioning, yet they are often overlooked in conservation studies. Many studies have reported a dramatic decline of insects globally, where climate change is considered a profound threat; however, how climate change is impacting tropical insects is largely unknown, given most studies are from the temperate region. Here, by considering Bangladeshi butterflies as a case study, I developed climatic suitability maps for 242 species and compared the suitability under current and future (2081-2100) climatic conditions. Overall, the projected future climate could impact 241 of 242 butterfly species (except for Spindasis elima), where 42% species could experience range contraction. Alarmingly, the impact could be significantly more severe among threatened species. While the direction of shift in habitat suitability could be multidimensional, about 65% of species might move north. While the suitability range could expand for about 58%, most threatened species (58%) could experience range contraction. The mean elevation of the suitable habitat could increase by 238%, and again the situation could be more severe for the threatened butterflies (from 42m to 108m). The niche-overlap analysis indicates that about 54% of the realised niche could be altered. Although there might be no significant association between the shift in habitat suitability along the elevational gradient, migratory species could experience a more significant shift than non-migrants. I show that climate change could have a severe impact on Bangladeshi butterflies – depending on Socio-Economic Pathways (ssps), the future climatic condition could be unsuitable for 2 (ssp126) – 34% (ssp585) species. To mitigate insect decline globally, and therefore, to meet the Post 2020 Biodiversity Framework targets, I urge immediate detection of climate change impact on tropical insects and developing effective conservation strategies.

Objectives: To evaluate risks of preterm birth and severe maternal morbidity (SMM) in female adolescent and young adult cancer survivors; assess maternal comorbidity as a potential mechanism; determine whether associations differ by use of assisted reproductive technology (ART). Design: Retrospective cohort Setting: Privately insured females in the U.S. Sample: Female with live births from 2000 to 2019 within OptumLabs®, a U.S. administrative health claims dataset Methods: Log-binomial regression models estimated relative risks of preterm birth and SMM by cancer status and tested for effect modification. Causal mediation analysis based on a counterfactual approach evaluated the proportions explained by maternal comorbidity. Main Outcome Measures: SMM, preterm birth Results: Among 46,064 cancer survivors, 2,440 singleton births, 214 multiple births, and 2,590 linked newborns occurred after cancer. In singleton births, preterm birth incidence was 14.8% in cancer survivors versus 12.4% in females without cancer (aRR 1.19, 95%CI 1.06-1.34); SMM incidence was 3.9% in cancer survivors versus 2.4% in females without cancer (aRR 1.44, 95%CI 1.13-1.83). Cancer survivors had more maternal comorbidities before and during pregnancy; 26% of the association between cancer and preterm birth and 30% of the association between cancer and SMM was mediated by maternal comorbidities. Associations between cancer and outcomes did not differ between ART and non-ART births. Conclusion: Preterm birth and SMM risks were modestly increased after cancer. Significant proportions of elevated risks may be due to increased comorbidities. Prevention and treatment of comorbidities provides an opportunity to improve perinatal outcomes among cancer survivors.

Objective: Preeclampsia (PE) is a leading cause of morbidity and mortality in pregnancy. This observational study aims to determine associations between oral and placental microbiome in women with and without preeclampsia and periodontal disease (PD) and evaluate systemic immune responses in patients with and without PE and PD. Population: Fifty-four pregnant patients with and without PE and PD were recruited. The microbiome profiles of both oral subgingival region and placenta were characterized by V4 region of 16S rRNA gene sequencing. Systemic inflammation markers tumor necrosis factor-alpha (TNF-α), C-reactive protein (CRP), lipopolysaccharide binding protein (LBP), interleukins 6 & 8 (IL-6, IL-8) in blood were measured by ELISA. Results: PD significantly increased the risk of PE after adjustments for age, preterm delivery and smoking status (OR=2.26, 95% CI=1.14-4.48, p=0.024). A group of oral associated bacteria Veilonella, Fusobacterium, Haemophilus, Granulicatella, Streptococcus, Gemella and Neisseria in placenta had significantly higher prevalence in women with PE compared to women without PE (53.8% vs 19.0%, p=0.018), the highest prevalence in patients with both PE and PD (58.8%). Relative abundances of Haemophilus, Veillonella and Fusobacterium in oral samples were significantly higher in patient with PE than those without PE. Proinflammation cytokine analysis showed that PE patients with PD had higher blood IL-8 levels than PE patients without PD (p=0.028). Conclusion: Oral-like microbiome was identified in placenta more frequently in patients with PE than those without PE. Placental microbiome is associated with systemic inflammation. High abundances of Haemophilus in oral cavity is associated with increased risk of PE.

Both δ 18O in groundwater and speleothem are inherited from precipitation δ 18O, however, stalagmite δ 18O and groundwater δ 18O do not simultaneously agree with each other in the monsoon regions, especially in the late Pleistocene. The reason remains unclear due to the complex stable isotope systematics in the monsoon affected regions with their controlling factors as well as the possible different recharge dynamics of groundwater and drip water. In this study, we have collected 539 daily precipitation samples throughout 2015 from seven monitoring stations in Beijing, in the northern margin of the East Asian summer monsoon region. Stable isotopes (δ 18O and δ 2H) of these precipitation samples are investigated for the controlling factors of precipitation isotopes, e.g., moisture source, temperature (T), and precipitation amount (P) effects. The δ 18O values in the precipitation decrease from the south to the northwest, which is controlled by the monsoon from the south and continental moisture from the northwest. Consistently, the precipitation exhibits an apparent seasonal variation in δ 18O values. The P effect is significant during the monsoon season, especially when the precipitation events are greater than 5 mm and single moisture source is considered. In contrast, the T effect is significant, with a gradient of 0.4‰ per °C during the non-monsoon season. A Rayleigh distillation model indicates that the moisture source and residual vapor fraction are the two most important factors controlling the δ 18O precipitation patterns in a monsoon region, independent of temperature. Isotopes in groundwater in the late Pleistocene exhibit a significant T effect, implying that the monsoon might not reach Beijing when the groundwater was formed at that time. Furthermore, we highlighted the different recharge mechanisms of groundwater and drip water: lateral flow and direct vertical infiltration make diverse contributions of non-monsoon precipitations to the groundwater and drip water respectively, resulting in that speleothem δ 18O differ from groundwater δ 18O in the late Pleistocene.

This paper studies chatter stability of composite cutter bar milling system in rotating coordinate frame. Based on the structural dynamic equation and regenerative milling force model of composite cutter bar in rotating coordinate frame, the continuous distributed chatter analysis model of composite cutter bar milling system is established. The stability of milling system with a rotary symmetric dynamic cutter bar is predicted by using the semi-discrete time domain method. Influences including internal damping, external damping, symmetrical and asymmetric laminates on the stability of milling system are analyzed, and the results obtained in rotating and fixed coordinate frame are compared. It is shown that the results are consistent for symmetrical cutter bar either in the rotating coordinate frame or in the fixed coordinate frame. A new chatter instability zone appears at high rotating speeds due to material internal damping of the rotating composite cutter bar.

Background: In patients with non-sustained tachyarrhythmias, left ventricular (LV) systolic dysfunction is uncommon. The role of catheter ablation (CA) in asymptomatic patients with tachyarrhythmia remains unclear. Case presentation: We report a 20-year-old patient without sustained tachyarrhythmia with a left ventricular ejection fraction of 20% who underwent radiofrequency catheter ablation (RFCA) of anteroseptal accessory pathway. She achieved normalization of left ventricular systolic function noted on echocardiography performed at four weeks post-ablation. Conclusions: Our case highlights significant improvement in LV systolic function after catheter ablation of an “asymptomatic” ventricular preexcitation. Current guidelines do not endorse ablating asymptomatic patients, but careful follow up with serial echocardiograms might be warranted. Prophylactic ablation of those patients with clear evidence of LV dyssynchrony or wide left bundle branch pattern and persistent preexcitation is worth further consideration.