Changes in the Composition and Surface Properties of Torrefied Conifer Cones

The paper investigated the torrefaction of cones from three tree species: Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies L.), and European larch (Larix decidua Mill.). The objective was to determine the effects of torrefaction temperature on the properties of cones with a view to their further use as a renewable energy source. Torrefaction was conducted at 200, 235, 275, and 320 °C for 60 min under an inert gas atmosphere. Elemental composition, ash content, and lower heating value (LHV) were measured for the original and torrefied samples. Torrefaction performance was evaluated using formulas for solid yield, higher heating value (HHV), HHV enhancement factor, as well as energy yield. Scanning electron microscopy (SEM) was used to assess elemental composition and structural changes at the surface of the torrefied material. For all the studied conifer species, the higher the torrefaction temperature, the greater the carbon and ash content and the higher the LHV (a maximum of 27.6 MJ·kg⁻¹ was recorded for spruce and larch cones torrefied at 320 °C). SEM images showed that an increase in process temperature from 200 to 320 °C led to partial decomposition of the scale surface as a result of lignin degradation. Cone scales from all tree species revealed C, O, N, Mg, K, and Si at the surface (except for pine scales, which did not contain Si). Furthermore, the higher the temperature, the higher the enhancement factor and the lower the energy yield of the torrefied biomass. Under the experimental conditions, spruce cones were characterized by the lowest weight loss, the highest HHV, and the highest energy yield, and so they are deemed the best raw material for torrefaction among the studied species.     

2种加温方式预防婴儿先天性巨结肠手术中低体温的效果比较

目的 探讨2种加温方式预防先天性巨结肠症（HD）患儿术中低体温的效果。方法 选取2016年11月至2019年12月在安徽省儿童医院行Soave术患儿50例,根据数字的奇偶性随机分为电阻升温毯组（R组,n=26）与充气加温毯组（F组,n=24）。结果 两组患儿体温存在组别效应（P<0.05）,麻醉诱导后第30分钟体温开始下降,不同时间点体温变化差异有统计学意义（P<0.05）,但这种体温体温随着时间的改变因分组而不同（P<0.05）。两组患儿不同时间点MAP、HR变化差异具有统计学意义（P<0.05）。F组患儿手术结束到自主呼吸恢复时间、气管导管拔出时间及苏醒室复苏时间均短于R组,差异有统计学意义（P<0.05）。结论 在Soave术中使用充气加温毯,能有效维持HD患儿术中体核温度的稳定。     

Intracranial venous malformations: Incidence and characterization in a large pediatric cohort

BackgroundSignificant advances have been reported recently in the genetic and mechanistic characterization of extracranial venous malformations. However, intracranial purely venous malformations (icVM) analogous to those outside the CNS have not been systematically described.PurposeWe sought to ascertain whether such an entity as icVM could in fact be identified, distinct from previously described CNS venous anomalies and analogous to extracranial venous malformations.MethodsOur prospectively collected pediatric cerebrovascular database was reviewed to identify patients with icVM; 1458 consecutive angiograms and/or angiographic interventions performed on 706 children at our institution from October, 2006 through May, 2019 were evaluated, in addition to outside imaging studies on 192 additional patients sent to our Vascular Anomalies Center for cerebrovascular review during the same time period. Thus, the cohort consisted of 898 children.ResultsNineteen of 898 patients (2.1%) were found to harbor icVM, including 9 (47.3%) with sinus pericranii, 15 (78.9%) with associated large, complex extracranial venous malformations, and 3 (15.7%) with neurocognitive delay. There was no intracranial hemorrhage or venous hypertension seen in the cohort. Asymptomatic venous thrombosis in the superior sagittal sinus was seen in three patients.ConclusionVenous malformations, both extracranial and icVM, share many characteristics that are distinct from developmental venous anomalies. icVM were not associated with venous hypertension. The underlying genetic mutations involved in the development of icVM, germ-line or somatic, remain to be elucidated, but may very well involve shared mechanisms and pathways with extracranial venous malformations.     

产前超声诊断妊娠11~13+6周胎儿体蒂异常的应用价值

目的探讨产前超声对妊娠11~13+6周胎儿体蒂异常的诊断价值。方法回顾性分析我院产前超声诊断的19例妊娠11~13+6周胎儿体蒂异常的超声图像特征及其随访结果。结果19例体蒂异常的胎儿中,单胎16例、双胎3例,均有不同程度的胸腹壁缺损、内脏外翻和脊柱发育异常,其中脐带异常18例,肢体发育异常9例,露脑畸形2例,静脉导管异常9例,颈部透明层增厚2例,颈部水囊瘤3例,腹腔囊性占位2例,泄殖腔发育异常1例,巨膀胱1例,门体分流1例。结论产前超声检查对胎儿体蒂异常的早期诊断和确定临床处理决策具有重要的应用价值。     

In vitro characterisation of ultrasound-induced heating effects in the mother and fetus: A clinical perspective

IntroductionThe quantification of heating effects during exposure to ultrasound is usually based on laboratory experiments in water and is assessed using extrapolated parameters such as the thermal index. In our study, we have measured the temperature increase directly in a simulator of the maternal–fetal environment, the ‘ISUOG Phantom’, using clinically relevant ultrasound scanners, transducers and exposure conditions.MethodsThe study was carried out using an instrumented phantom designed to represent the pregnant maternal abdomen and which enabled temperature recordings at positions in tissue mimics which represented the skin surface, sub-surface, amniotic fluid and fetal bone interface. We tested four different transducers on a commercial diagnostic scanner. The effects of scan duration, presence of a circulating fluid, pre-set and power were recorded.ResultsThe highest temperature increase was always at the transducer–skin interface, where temperature increases between 1.4°C and 9.5°C were observed; lower temperature rises, between 0.1°C and 1.0°C, were observed deeper in tissue and at the bone interface. Doppler modes generated the highest temperature increases. Most of the heating occurred in the first 3 minutes of exposure, with the presence of a circulating fluid having a limited effect. The power setting affected the maximum temperature increase proportionally, with peak temperature increasing from 4.3°C to 6.7°C when power was increased from 63% to 100%.ConclusionsAlthough this phantom provides a crude mimic of the in vivo conditions, the overall results showed good repeatability and agreement with previously published experiments. All studies showed that the temperature rises observed fell within the recommendations of international regulatory bodies. However, it is important that the operator should be aware of factors affecting the temperature increase.     

Resolution adapted finite element modeling of radio frequency interactions on conductive resonant structures in MRI

Prediction of interactions between the radiofrequency electromagnetic field in magnetic resonance scanners and electrically conductive material surrounded by tissue plays an increasing role for magnetic resonance safety. Testing of conductive implants or instruments is usually performed by standardized experimental setups and temperature measurements at distinct geometrical points, which cannot always reflect worst-case situations. A finite element method based on Matlab (The Mathworks, Natick, MA) and the finite element method program Comsol Multiphysics (Stockholm, Sweden) with a spatially highly variable mesh size solving Maxwell's full-wave equations was applied for a comprehensive simulation of the complete geometrical arrangement of typical birdcage radiofrequency coils loaded with small conductive structures in a homogenous medium. Conductive implants like rods of variable length and closed and open ring structures, partly exhibiting electromagnetic resonance behavior, were modeled and evaluated regarding the distribution of the B(1)- and E-field, induced currents and specific absorption rates. Numerical simulations corresponded well with experiments using a spin-echo sequence for visualization of marked B(1)-field inhomogeneities. Even resonance effects in conductive rods and open rings with suitable geometry were depicted accurately. The proposed method has high potential for complementation or even replacement of common experimental magnetic resonance compatibility measurements.     

Qualitative Interpretive Metasynthesis of Parents’ Experiences of Perinatal Loss

ObjectiveTo identify and synthesize common, experiential themes from qualitative studies of parents who experienced perinatal loss.Data SourcesWe searched PubMed, CINAHL, and PsycINFO for qualitative articles about parents’ experiences of perinatal loss.Study SelectionWe included research on parents’ experiences of perinatal loss published in English in the last 10 years. We excluded articles on the perspectives or experiences of health care professionals or persons other than the biological parent who experienced the perinatal loss, systematic reviews, outcome studies, and gray literature.Data ExtractionWe used a priori inclusion and exclusion criteria and identified five articles in which perinatal loss was described from the parents’ perspectives. We extracted thematic findings and supporting quotes from each article and documented them in a table for subsequent synthesis.Data SynthesisWe used a qualitative metasynthesis and interpretive model to synthesize findings from the included studies. Findings were synthesized into one overarching theme, The Paradox of Perinatal Loss, and four subthemes: Complex Emotional Responses, Prenatal Bonding–Acknowledging Personhood, Interactions With Health Care Professionals, and Traversing the Social Sphere.ConclusionOur findings indicate that perinatal loss is often a transformative event during which parents experience multiple losses and intense, complex emotions. Interactions with health care professionals greatly affected the pregnancy experience, which places professionals in a unique position to positively influence parents’ overall experiences. Therefore, it is important to develop protocols related to perinatal loss and ensure that staff are adequately trained and equipped to care for parents during this experience. Findings from this synthesis may also inform the future development of theory related to bereavement surrounding perinatal loss.     

Increasing local blood flow by warming the application site: beneficial effects on postprandial glycemic excursions

The absorption profile of rapid-acting insulin analogs delivered subcutaneously is slow compared with physiological insulin. Shorter time to peak and shorter duration of insulin action are important steps toward reducing high postprandial blood glucose concentrations in diabetes therapy and are critical for the development of a closed-loop insulin delivery system. Many attempts have been made to develop more rapid-acting insulins. Since the 1950s, different approaches, such as jet injectors and sprinkler needles, which try to increase the absorption areas of injected insulin, have been developed; however, none of them are commonly used in diabetes therapy. Massage and heat increase tissue blood perfusion and, thereby, the absorption of subcutaneously applied insulin. The main focus of this article is a novel device that allows local application of heat to human skin. The device can be connected to a regular insulin pump. This device could demonstrate a significant effect on insulin absorption and postprandial glucose excursions in multiple clinical trials.     

尿路造口袋在男性尿失禁患者护理中的应用

目的探讨对失血性休克患者进行早期加温输液输血的必要性。方法选择我院ICU 2011年8月~2013年8月入院诊断为失血性休克的患者45例,根据早期抗休克治疗过程中是否加温输液输血分为加温治疗组23例和未加温治疗组22例。比较两组部分凝血活酶时间（APTT）、凝血酶原时间（PT）、酸中毒程度（PH值）、ICU驻留时间、寒战发生率及死亡率。结果两组PH值、APTT、PT、ICU驻留时间比较有显著性差异（P〈0.05）;两组寒战发生率、死亡率比较有显著性差异（P〈0.05）。结论对失血性休克患者进行早期加温输液输血,可明显改善机体组织灌注和供氧,改善凝血功能,减少器官衰竭,其护理对患者康复具有重要意义。     

纤维支气管镜对婴幼儿气道发育畸形诊断的应用价值

目的：探讨纤维支气管镜（纤支镜）在气道发育畸形中的作用价值及安全性。方法对我院儿科2011年6月-2013年12月期间的106例喉喘鸣伴呼吸困难、婴幼儿喘息、慢性咳嗽及反复呼吸道感染的婴幼儿行纤支镜检查,并将34例气道发育畸形患儿的检查结果及临床资料进行回顾性分析。结果106例患儿中发现气道发育畸形34例（32%）,其中喉部囊肿2例;会厌软骨软化5例;气管、支气管软化20例;气管、支气管狭窄3例;支气管起源异常并狭窄3例,气管食管瘘1例。结论纤支镜术对婴幼儿气道发育畸形的诊断发挥重要作用,能有效降低婴幼儿呼吸道疾病的漏诊和误诊,值得临床推广应用。