A forceful upper jaw facilitates picking-based prey capture: biomechanics of feeding in a butterflyfish,Chaetodon trichrous

Biomechanical models of feeding mechanisms elucidate how animals capture food in the wild, which, in turn, expands our understanding of their fundamental trophic niche. However, little attention has been given to modeling the protrusible upper jaw apparatus that characterizes many teleost species. We expanded existing biomechanical models to include upper jaw forces using a generalist butterflyfish, Chaetodon trichrous (Chaetodontidae) that produces substantial upper jaw protrusion when feeding on midwater and benthic prey. Laboratory feeding trials for C. trichrous were recorded using high-speed digital imaging; from these sequences we quantified feeding performance parameters to use as inputs for the biomechanical model. According to the model outputs, the upper jaw makes a substantial contribution to the overall forces produced during mouth closing in C. trichrous. Thus, biomechanical models that only consider lower jaw closing forces will underestimate total bite force for this and likely other teleost species. We also quantified and subsequently modeled feeding events for C. trichrous consuming prey from the water column versus picking attached prey from the substrate to investigate whether there is a functional trade-off between prey capture modes. We found that individuals of C. trichrous alter their feeding behavior when consuming different prey types by changing the timing and magnitude of upper and lower jaw movements and that this behavioral modification will affect the forces produced by the jaws during prey capture by dynamically altering the lever mechanics of the jaws. In fact, the slower, lower magnitude movements produced during picking-based prey capture should produce a more forceful bite, which will facilitate feeding on benthic attached prey items, such as corals. Similarities between butterflyfishes and other teleost lineages that also employ picking-based prey capture suggest that a suite of key behavioral and morphological innovations enhances feeding success for benthic attached prey items.     

Der Mengen- und Spurenelementgehalt des Rinderhaares als Indikator der Calcium-, Magnesium-, Phosphor-, Kalium-, Natrium-, Eisen-, Zink-, Mangan-, Kupfer-, Molybdän- und Kobaltversorgung

Beyond the energy requirement of maintenance, the assimilated energy, occurring in bioproducts, is linearly proportional to the intake of metabolizable energy in non‐underfed conditions. In contrast, resting metabolic rate is differing between individuals within a population of an animal species. As adaptability to changed environmental conditions may play a role, young bulls were exposed to thermoneutral (18°C) and low (4°C) ambient temperatures and were fed at two feeding levels (1.0 and 1.6 times energy requirement in maintenance) to produce metabolic rate differences, using the same animals, metabolic rate was altered by reducing the sympathetic outflow in each case. Expression of sulfonylurea receptors in circulating mononuclear leukocytes and cells from skeletal muscle (m. semitendinosus) was studied by flow cytom‐etry. Changes of metabolic rate at rest corresponded to the portion of cells with sulfonylurea receptors expression. The data from reducing the sympathetic outflow and those from sulfonylurea receptors expression are useful to explain metabolic rate differences among individuals of an animal population.     

An integrated practical implementation of continuous aqueous two‐phase systems for the recovery of human IgG: From the microdevice to a multistage bench‐scale mixer‐settler device

Aqueous two‐phase systems (ATPS) are a liquid‐liquid extraction technology with clear process benefits; however, its lack of industrial embracement is still a challenge to overcome. Antibodies are a potential product to be recovered by ATPS in a commercial context. The objective of this work is to present a more integral approach of the different isolated strategies that have arisen in order to enable a practical, generic implementation of ATPS, using human immunoglobulin G (IgG) as experimental model. A microfluidic device is used for ATPS parameters preselection for product recovery. ATPS were continuously operated in a mixer‐settler device in one stage, multistage and multistage with recirculation configuration. Single‐stage pure IgG extraction with a polyethylene glycol (PEG) 3350‐phophates ATPS within continuous operation allowed a 65% recovery. Further implementation of a multistage platform promoted a higher particle partitioning reaching a 90% recovery. The processing of IgG from a cell supernatant culture harvest in a multistage system with top phase recirculation resulted in 78% IgG recovery in bottom phase. This work conjugates three not widely spread methodologies for ATPS: microfluidics, continuous and multistage operation.     

Breaking the 10% Efficiency Barrier in Organic Photovoltaics: Morphology and Device Optimization of Well‐Known PBDTTT Polymers

With the advances in organic photovoltaics (OPVs), the invention of model polymers with superior properties and wide applicability is of vital importance to both the academic and industrial communities. The recent inspiring advances in OPV research have included the emergence of poly(benzodithiophene‐co‐thieno[3,4‐b]thiophene) (PBDTTT)‐based materials. Through the combined efforts on PBDTTT polymers, over 10% efficiencies have been realized recently in various types of OPV devices. This review attempts to critically summarize the recent advances with respect to five well‐known PBDTTT polymers and their design considerations, basic properties, photovoltaic performance, as well as device application in conventional, inverted, tandem solar cells. These PBDTTT polymers also make great contributions to the rapid advances in the field of emerging ternary blends and fullerene‐free OPVs with top performances. Addtionally, new challenges in developing novel photovoltaic polymers with more superior properties are prospected. More importantly, the research of highly efficient PBDTTT‐based polymers provides useful insights and builds fundamentals for new types of OPV applications with various architectures.     

简易注气法测定刺槐木质部导管组织长度

导管组织在木本植物水力学特性及水分关系中的作用逐渐受到关注,但其长度的传统测试装置和方法相对繁琐。本研究在注气法原理基础上进行改进,改进后装置简易、操作便捷。结果表明,本方法可以成功测定刺槐(Robinia pseudoacacia L.)导管的长度及相关参数:气体传导耗散系数为0.111±0.012;最大导管长度为56.9±1.5 cm;平均导管长度为19.6±2.5 cm;最大分布导管长度为9.8±1.3 cm。枝条注气方向对测试结果没有明显影响。测试过程中注气端压强变化不明显,对导管长度及相关参数的测定和计算影响不显著。本方法与传统注气法相比具有更高的精确度。     

红角鸮的食性及育雏行为初报

红角鸮(Otus sunia)广泛分布于东亚和南亚。2012和2013年的两个繁殖季节,在江苏省南京大学浦口校区通过红外摄像观察记录了红角鸮的摄食及育雏行为,统计了亲代红角鸮育雏食物的种类、育雏的时间和次数。以1 h为一个时段,利用单因素方差分析(ANOVA)及Student-Newman-Keulsa多重比较法分析各时段之间育雏频次的差异。亲鸟育雏的食物大部分为直翅目(62%)和鳞翅目(18%)昆虫,以及非昆虫类的无脊椎动物,如蜘蛛(8%)和唇足动物(7%),红角鸮也捕食小型陆栖脊椎动物例如田鼠、壁虎等育雏,但比例甚低(3%)。红角鸮育雏节律较为明显,亲鸟主要集中在夜间外出觅食,但在白天也有觅食行为。夜间共有三个育雏高峰,分别为日落之后的19:00~20:00时和21:00~22:00时以及日出之前的04:00~05:00时。     

长江上游中华沙鳅食性特征的C、N同位素分析

应用C、N稳定同位素技术并结合肠含物分析对我国长江上游特有鱼类中华沙鳅（Sinibotia superciliaris）不同发育阶段食性进行了探究。结果显示:中华沙鳅13C、15N平均值分别为（22.480.85）、（10.090.69）;不同体长段13C（P0.05,F=2.44）、15N（P0.01,F=6.06）值差异显著,暗示了中华沙鳅在生长发育过程中存在食性转变现象;体长80 mm的个体主要摄食水生昆虫和藻类,属杂食偏肉食性鱼类;体长80 mm的个体,其食物以虾类、淡水壳菜和水生昆虫为主,属肉食性鱼类。中华沙鳅营养级位于2.02-2.47,与长江上游多种底栖型鱼类生态位相似;食物竞争可能是导致其摄食强度弱和资源量下降的原因之一。研究结果可为长江上游中华沙鳅野生资源保护提供理论参考。     

Gyroscopic corrections improve wearable sensor data prior to measuring dynamic sway in the gait of people with Multiple Sclerosis

Accelerometers are incorporated into many consumer devices providing new ways to monitor gait, mobility, and fall risk. However, many health benefits have not been realised because of issues with data quality that results from gravitational ‘cross-talk’ when the wearable device is tilted. Here we present an adaptive filter designed to improve the quality of accelerometer data prior to measuring dynamic pelvic sway patterns during a six minute walk test in people with and without Multiple Sclerosis (MS). Optical motion capture was used as the gold standard. Improved wearable device accuracy (≤4.4% NRMSE) was achieved using gyroscopic corrections and scaling filter thresholds by step frequency. The people with MS presented significantly greater pelvis sway range to compensate for their lower limb weaknesses and joint contractures. The visualisation of asymmetric pelvic sway in people with MS illustrates the potential to better understand their mobility impairments for reducing fall risk.     

镍钛形状记忆合金环抱器内固定术对多发性肋骨骨折患者术后疼痛、呼吸功能及肺部感染的影响

目的:探讨多发性肋骨骨折患者采用镍钛形状记忆合金环抱器内固定术治疗的临床效果。方法:选取2016年1月-2018年1月期间我院收治的97例多发性肋骨骨折患者。按照不同的治疗方法将患者分为对照组(n=47)和研究组(n=50),对照组患者给予胸部护板外固定术,研究组患者给予镍钛形状记忆合金环抱器内固定术。比较两组患者术后7 d的临床疗效,比较两组术前、术后7 d疼痛程度及呼吸功能情况,记录两组术后并发症发生情况。结果:研究组患者治疗后总有效率为92.00%(46/50),高于对照组患者的76.60%(36/47)(P0.05)。两组患者术后7 d视觉疼痛模拟评分量表(VAS)评分均较术前降低,且研究组低于对照组(P0.05)。两组患者术后7 d最大自主通气量占预计值百分比(MVV%)较术前升高,且研究组高于对照组(P0.05);两组患者术后7 d第1秒用力呼气肺活量占预计值百分比(FEV1%)比较无差异(P0.05)。研究组患者术后并发症总发生率8.00%(4/50),低于对照组的23.40%(11/47)(P0.05)。结论:多发性肋骨骨折经镍钛形状记忆合金环抱器内固定术治疗安全、有效,可明显减轻患者术后疼痛及改善呼吸功能,临床应用价值较高。