Harmful evaluation of heavy metals from soil layer to the groundwater: Take the Jilin Hunchun Basin as an example

The continuous enrichment of heavy metals in soils has caused potential harm to groundwater.Quantitative methods to evaluate the harm of heavy metals in soil to groundwater are lacked in previous studies.Based on the theory of groundwater circulation and solid-liquid equilibrium,a simple and easy-touse flux model of soil heavy metals migrating to groundwater is constructed.Based on groundwater environmental capacity,an innovative method for evaluating the harm of heavy metals in soil to groundwater is proposed,which has been applied in Hunchun Basin,Jilin Province,China.The results show that the fluxes of soil heavy metals into groundwater in the study area are Zn,Cu,As,Pb,Cd,Ni,and Hg in descending order.The content of heavy metals in groundwater(As,Hg,Cu,Pb,Zn,Ni,and Cd)in most areas has not risen to the threshold of environmental capacity within 10 years.The harm levels of soil heavy metals to groundwater in the most townships soils are at the moderate level or below.This evaluation method can quantify the flux of soil heavy metals into groundwater simply and quickly,determine the residual capacity of groundwater to heavy metals,evaluate the harm level of soil heavy metals to groundwater,provide support for relevant departments to carry out environmental protection of soil and groundwater,and provide a reference to carry out similar studies for related scholars.

Performance of the walking trail making test in older adults with white matter hyperintensities

BACKGROUND Several studies have reported that the walking trail making test(WTMT)completion time is significantly higher in patients with developmental coordination disorders and mild cognitive impairments.We hypothesized that WTMT performance would be altered in older adults with white matter hyperintensities(WMH).AIM To explore the performance in the WTMT in older people with WMH.METHODS In this single-center,observational study,25 elderly WMH patients admitted to our hospital from June 2019 to June 2020 served as the WMH group and 20 participants matched for age,gender,and educational level who were undergoing physical examination in our hospital during the same period served as the control group.The participants completed the WTMT-A and WTMT-B to obtain their gait parameters,including WTMT-A completion time,WTMT-B completion time,speed,step length,cadence,and stance phase percent.White matter lesions were scored according to the Fazekas scale.Multiple neuropsychological assessments were carried out to assess cognitive function.The relationships between WTMT performance and cognition and motion in elderly patients with WMH were analyzed by partial Pearson correlation analysis.RESULTS Patients with WMH performed significantly worse on the choice reaction test(CRT)(0.51±0.09 s vs 0.44±0.06 s,P=0.007),verbal fluency test(VFT,14.2±2.75 vs 16.65±3.54,P=0.012),and digit symbol substitution test(16.00±2.75 vs 18.40±3.27,P=0.010)than participants in the control group.The WMH group also required significantly more time to complete the WTMT-A(93.00±10.76 s vs 70.55±11.28 s,P<0.001)and WTMT-B(109.72±12.26 s vs 82.85±7.90 s,P<0.001).WTMT-A completion time was positively correlated with CRT time(r=0.460,P=0.001),while WTMT-B completion time was negatively correlated with VFT(r=-0.391,P=0.008).On the WTMT-A,only speed was found to statistically differ between the WMH and control groups(0.803±0.096 vs 0.975±0.050 m/s,P<0.001),whereas on the WTMT-B,the WMH group exhibited a significantly lower speed(0.778±0.111 vs 0.970±0.053 m/s,P<0.001)and cadence(82.600±4.140 vs 85.500±5.020 steps/m,P=0.039),as well as a higher stance phase percentage(65.061±1.813%vs 63.513±2.465%,P=0.019)relative to controls.CONCLUSION Older adults with WMH showed obviously poorer WTMT performance.WTMT could be a potential indicator for cognitive and motor deficits in patients with WMH.

Analysis of quality of life in patients after transgastric natural orifice transluminal endoscopic gallbladder-preserving surgery

BACKGROUND At present,laparoscopic cholecystectomy(LC)is the main surgical treatment for gallstones.But,after gallbladder removal,there are many complications.Therefore,it is hoped to remove stones while preserving the function of the gallbladder,and with the development of endoscopic technology,natural orifice transluminal endoscopic surgery came into being.AIM To compare the quality of life,perioperative indicators,adverse events after LC and transgastric natural orifice transluminal endoscopic gallbladder-preserving surgery(EGPS)in patients with gallstones.METHODS Patients who were admitted to The First Affiliated Hospital of Xinjiang Medical University from 2020 to 2022 were retrospectively collected.We adopted propen-sity score matching(1:1)to compare EGPS and LC patients.RESULTS A total of 662 cases were collected,of which 589 cases underwent LC,and 73 cases underwent EGPS.Propensity score matching was performed,and 40 patients were included in each of the groups.In the EGPS group,except the gastr-ointestinal defecation(P=0.603),the total score,physical well-being,mental well-being,and gastrointestinal digestion were statistically significant compared with the preoperative score after surgery(P<0.05).In the LC group,except the mental well-being,the total score,physical well-being,gastrointestinal digestion,the gastrointestinal defecation was statistically significant compared with the preoperative score after surgery(P<0.05).When comparing between groups,gastrointestinal defecation had significantly difference(P=0.002)between the two groups,there was no statistically significant difference in the total postoperative score and the other three subscales.In the surgery duration,hospital stay and cost,LC group were lower than EGPS group.The recurrence factors of gallstones after EGPS were analyzed:and recurrence was not correlated with gender,age,body mass index,number of stones,and preoperative score.CONCLUSION Whether EGPS or LC,it can improve the patient’s symptoms,and the EGPS has less impact on the patient’s defecation.It needed to,prospective,multicenter,long-term follow-up,large-sample related studies to prove.

Drug-coated balloons for treating de novo lesions in large coronary vessels:A case report

BACKGROUND Percutaneous transluminal coronary angioplasty,while an effective intervention,can frequently lead to acute occlusion with severe consequences.Although clinical trials have demonstrated the efficacy of drug-coated balloons(DCB)in treating acute coronary artery occlusion and in preventing restenosis,there has been limited exploration on the use of DCB in treating de novo lesions in large vessels.Currently,DCB are only recommended for patients with small vessel lesions and in-stent restenosis lesions,those at high risk of bleeding,and other special groups of patients.CASE SUMMARY This report presents a case of successful drug-coated balloon treatment of de novo lesions in large coronary vessels.Postoperatively,the patient demonstrated favorable recovery,with subsequent examination results revealing no significant differences from the previous examination.CONCLUSION The successful treatment of the patient in our case highlights the potential of DCB in the treatment of de novo lesions in large coronary vessels.

直肠神经内分泌肿瘤的内镜下诊断与治疗

目的分析直肠神经内分泌肿瘤(R-NENs)的临床病理学特征,并探讨R-NENs内镜下的诊断特点及内镜下治疗的效果及安全性。方法回顾性分析2010年1月-2019年9月就诊于新疆医科大学第一附属医院并行常规结肠镜检查的76例R-NENs患者的临床资料,均经组织标本活检或手术切除瘤体病理检查明确诊断为R-NENs。结果肿瘤位于低位直肠段32例(42.11%),中段25例(32.89%),下段19例(25.00%)。36例行超声内镜(EUS)检查,其中27例EUS下诊断为R-NENs,2例诊断为间质瘤,6例诊断为脂肪瘤,1例诊断为平滑肌瘤,与病理结果诊断符合率达75.00%(27/36)。29例病例行内镜黏膜下剥离术(ESD),22例行内镜下黏膜切除术(EMR),20例行内镜经黏膜下隧道肿物剥离术(STER),2例行电凝电切术,3例因不同原因未通过上述内镜手术方式进行治疗。所有患者中69例行病理学检查及免疫组化检查,结果证实G1级最多见,共62例,占所有病例的81.58%(62/76)。结论R-NENs以男性多见,好发于中低位直肠段,其中G1级最为常见;EUS技术的成熟运用能够对病变性质及组织学起源进行较准确的判断,但也存在一定的误诊率,最终还应以病理结果为金标准;早期G1、G2级R-NENs经内镜治疗是安全有效的,并且能够提供较完整的病理学资料。

食管黏膜下肿瘤的内镜下诊断与治疗

目的基于食管黏膜下肿瘤(SMTs)内镜检查及治疗手段,分析食管SMTs的临床病理学特征,同时评价食管SMTs内镜下诊治的安全性、经济性和有效性。方法选择2012年1月-2017年12月新疆医科大学第一附属医院收治的98例食管SMTs患者,并同时完善普通胃镜和超声内镜(EUS)检查,所有患者均接受内镜下治疗,所有切除的肿瘤均行病理学检查。结果共98例患者。其中,女55例(56.12%),男43例(43.88%)。肿瘤位于食管上段27例(27.55%),中段28例(28.57%),下段43例(43.88%),56例病例行内镜黏膜下剥离术(ESD),25例行内镜黏膜下肿瘤挖除术(ESE),12例行内镜黏膜下隧道肿瘤切除术(STER),另3例行电凝电切除术,1例孤立性纤维性肿瘤因术中发现肿瘤基底部深转为外科手术,另1例平滑肌瘤因肿瘤体积太大致内镜操作困难,中途转胸腔镜下治疗。1例神经鞘瘤,ESD术后出现气胸、胸腔积液、术后瘘及食管狭窄等并发症,1例胸腔镜下行肿瘤摘除术的平滑肌瘤,术后发生气胸和胸腔积液,另外2例出现纵隔气肿和皮下气肿,均于术后2或3 d自行好转。病理学检查及免疫组化结果证实,最常见的食管SMTs为平滑肌瘤,共90例,占所有病例91.84%。结论食管SMTs以女性多见,好发于中下段食管,病理以平滑肌瘤最为常见;应用EUS技术能够对病变性质及组织学来源进行较准确的评估;内镜下治疗食管SMTs不仅能提供完整的病理学资料,而且有效安全。

结肠镜检查人群肛门HPV感染情况调查及危险因素分析

目的旨在研究结肠镜检查人群肛门人类乳头状病毒(HPV)的感染情况,并分析肛门HPV感染的相关危险因素。方法选取2014年11月-2016年11月新疆医科大学第一附属医院内镜中心行结肠镜检查的273例患者行问卷调查,同时采用肛门刷采集脱落上皮细胞,在显微镜下观察病理改变,HC2法联合基因芯片法行HPV-DNA检测及基因分型。结果在273例标本中检出HPV-DNA阳性8例,总感染率为2.93%,其中4例为(52+58)型,2例16型,1例35型,1例39型,均属于高危型HPV,显微镜下观察均未见明显的病理改变。年龄、文化程度、消化道症状是影响肛门HPV感染的危险因素(P<0.05)。结论结肠镜检查人群存在着一定的HPV感染率。年龄、文化程度、消化道症状是影响肛门HPV感染的危险因素。

Identification of Annexin A1 protein expression in human gastric adenocarcinoma using proteomics and tissue microarray

AIM:To study the differential expression of Annexin A1(ANXA1)protein in human gastric adenocarcinoma.This study was also designed to analyze the relationship between ANXA1 expression and the clinicopathological parameters of gastric carcinoma.METHODS:Purified gastric adenocarcinoma cells(GAC)and normal gastric epithelial cells(NGEC)were obtained from 15 patients with gastric cancer by laser capture microdissection.All of the peptide specimens were labeled as18O/16O after trypsin digestion.Differential protein expressions were quantitatively identified between GAC and NGEC by nanoliter-reverse-phase liquid chromatography-mass/mass spectrometry(nanoRPLC-MS/MS).The expressions of ANXA1 in GAC and NGEC were verified by western blot analysis.The tissue microarray containing the expressed ANXA1 in 75 pairs of gastric carcinoma and paracarcinoma specimens was detected by immunohistochemistry(IHC).The relationship between ANXA1 expression and clinicopathological parametes of gastric carcinoma was analyzed.RESULTS:A total of 78 differential proteins were identified.Western blotting revealed that ANXA1 expression was significantly upregulated in GAC(2.17/1,P<0.01).IHC results showed the correlations between ANXA1protein expression and the clinicopathological parameters,including invasive depth(T stage),lymph node metastasis(N stage),distant metastasis(M stage)and tumour-lymph node metastasis stage(P<0.01).However,the correlations between ANXA1 protein expression and the remaining clinicopathological parameters,including sex,age,histological differentiation and the size of tumour were not found(P>0.05).CONCLUSION:The upregulated ANXA1 expression may be associated with carcinogenesis,progression,invasion and metastasis of GAC.This protein could be considered as a biomarker of clinical prognostic prediction and targeted therapy of GAC.

Effect of ultrasonic melt treatment on degassing of Mg-6Zn-1Ca alloy

The effect of ultrasonic power and treatment time on degassing of Mg-6Zn-1Ca alloy was studied in this paper. The degassing effect was characterized by measuring densities of ingots. The results show that proper ultrasonic treatment can remove hydrogen from the melt of the Mg-6Zn-1Ca alloy. The ultrasonic degassing effect is closely related to the ultrasonic power density and treatment time. The degassing efficiency increases with an increase in ultrasonic power density when the melt is treated at 690 °C for 120 s, reaching its highest value at 1.2 W·cm-3. When the power density is 1.2 W·cm-3, with an increase in ultrasonic treatment time, the degassing efficiency increases at first, reaches its peak value at 120 s, then decreases as the ultrasonic treatment is further prolonged. In this experiment, the optimum degassing effect with an efficiency of 67.5 % is obtained by ultrasonic treatment with the power density of 1.2 W·cm-3 for 120 s. The maximum density of ingot can be increased from 1.8069 g·cm-3 to 1.8146 g·cm-3(increased by 0.43%).

Comparison of walking quality variables between incomplete spinal cord injury patients and healthy subjects by using a footscan plantar pressure system

The main goal of spinal cord rehabilitation is to restore walking ability and improve walking quality after spinal cord injury(SCI). The spatiotemporal parameters of walking and the parameters of plantar pressure can be obtained using a plantar pressure analysis system. Previous studies have reported step asymmetry in patients with bilateral SCI. However, the asymmetry of other parameters in patients with SCI has not been reported. This was a prospective, cross-sectional study, which included 23 patients with SCI, aged 48.1 ± 14.5 years, and 28 healthy subjects, aged 47.1 ± 9.8 years. All subjects underwent bare foot walking on a plantar pressure measurement device to measure walking speed and spatiotemporal parameters. Compared with healthy subjects, SCI patients had slower walking speed, longer stride time and stance time, larger stance phase percentage, and shorter stride length. The peak pressures under the metatarsal heads and toe were lower in SCI patients than in healthy subjects. In the heel, regional impulse and the contact area percentage in SCI patients were higher than those in healthy subjects. The symmetry indexes of stance time, step length, maximum force, impulse and contact area were increased in SCI patients, indicating a decline in symmetry. The results confirm that the gait quality, including spatiotemporal variables and plantar pressure parameters, and symmetry index were lower in SCI patients compared with healthy subjects. Plantar pressure parameters and symmetry index could be sensitive quantitative parameters to improve gait quality of SCI patients. The protocols were approved by the Clinical Research Ethics Committee of Shengjing Hospital of China Medical University(approval No. 2015 PS54 J) on August 13, 2015. This trial was registered in the ISRCTN Registry(ISRCTN42544587) on August 22, 2018. Protocol version: 1.0.

Trigeminal extracranial thermocoagulation along with patientcontrolled analgesia with esketamine for refractory postherpetic neuralgia after herpes zoster ophthalmicus:A case report

BACKGROUND Primary trigeminal neuralgia can achieve satisfactory results through clinical treatment and intervention.The pathogenesis of neuralgia caused by varicellazoster virus infection of the trigeminal nerve is more complex,and it is still difficult to relieve the pain in some patients simply by drug treatment or surgical intervention.CASE SUMMARY A 66-year-old woman was hospitalized with herpetic neuralgia after herpes zoster ophthalmicus(varicella-zoster virus infects the ophthalmic branch of the trigeminal nerve).On admission,the patient showed spontaneous,electric shocklike and acupuncture-like severe pain in the left frontal parietal region,and pain could be induced by touching the herpes area.The numerical rating scale(NRS)was 9.There was no significant pain relief after pulsed radiofrequency and thermocoagulation of the ophthalmic branch of the trigeminal nerve.Combined with patient-controlled intravenous analgesia(PCIA)with esketamine,neuralgia was significantly improved.The patient had no spontaneous pain or allodynia at discharge,and the NRS score decreased to 2 points.The results of follow-up 2 mo after discharge showed that the NRS score was≤3,and the Pittsburgh Sleep Quality Index score was 5 points.There were no adverse reactions.CONCLUSION Trigeminal extracranial thermocoagulation combined with esketamine PCIA may be a feasible method for the treatment of refractory herpetic neuralgia after herpes zoster ophthalmicus.

Ultrasonic flaw detection of discontinuous defects in magnesium alloy materials

Phased array ultrasonic testing, an effective ultrasonic testing(UT) technology, has been widely used in steel inspection because of its high accuracy, sensitivity, and efficiency. However, as its application in as-cast magnesium alloys has just begun, more research is needed. Considering the important role of the gain compensation in quantifying defects in magnesium alloys by ultrasonic phased array technology, the effects of microstructure, the position, size, and overlap of defects, and boundary distance(distance from the defect position to the side surface of the test casting) on gain compensation of as-cast AZ80 and AZ31 magnesium alloys were studied. Results show the gain compensation increases with the increase of grain size. There is a strict linear positive correlation between gain compensation and defect depth, but such relationship no longer exists due to the defects overlap, orientation and boundary distance. In addition, there is a strict linear negative correlation between the gain compensation and defect size.

Protective effect of tetrahydroxy stilbene glucoside on learning and memory by regulating synaptic plasticity

Damage to synaptic plasticity induced by neurotoxicity of amyloid-beta is regarded to be one of the pathological mechanisms of learning and memory disabilities in Alzheimer＇s disease patients. This study assumed that the damage of amyloid-beta to learning and memory abilities was strongly associated with the changes in the Fyn/N-methyl-D-aspartate receptor 2B （NR2B） expression. An APP695V7171 transgenic mouse model of Alzheimer＇s disease was used and treatment with tetrahydroxy-stilbene glucoside was administered intragas- trically. Results showed that intragastric administration of tetrahydroxy-stilbene glucoside improved the learning and memory abilities of the transgenic mice through increasing NR2B receptors and Fyn expression. It also reversed parameters for synaptic interface structure of gray type I. These findings indicate that tetrahydroxy stilbene glucoside has protective effects on the brain, and has prospects for its clinical application to improve the learning and memory abilities and treat Alzheimer＇s disease.

Effect of limestone ores on grain refinement of as-cast commercial AZ31 magnesium alloys

The grain refinement of the as-cast AZ31 alloys by limestone particles was investigated by grain refining tests and microstructure observations. The results show that the limestone particles have a good grain refining potency, which is deeply related to the addition level of limestone and melting temperature. The optimal addition level and melting temperature are 2.0%（mass fraction） and 720 ℃, respectively. The average grain size of AZ31 alloy is reduced from（556±60） to（236±22） μm. The sound grain refining by raw limestone particles has a good anti-fading capacity without any significant grain coarsening in a 40 min holding time. The concerned grain refining mechanism should be attributed to the inoculated Al-C and Al-C/Al-Mn-（Fe） nuclei. Ultrasonic treatment can enhance the grain refining efficiency of limestone particles through cavitation-enhanced nucleation mechanism.

Numerical analysis of added mass and damping of floating production,storage and offloading system

An integral equation approach is utilized to in- vestigate the added mass and damping of floating produc- tion, storage and offloading system （FPSO system）. Finite water depth Green function and higher-order boundary ele- ment method are used to solve integral equation. Numeri- cal results about added mass and damping are presented for odd and even mode motions of FPSO. The results show ro- bust convergence in high frequency range and can be used in wave load analysis for FPSO designing and operation.

Topological Anderson insulator in two-dimensional non-Hermitian systems

We study the disorder-induced phase transition in two-dimensional non-Hermitian systems.First,the applicability of the noncommutative geometric method(NGM)in non-Hermitian systems is examined.By calculating the Chern number of two different systems(a square sample and a cylindrical one),the numerical results calculated by NGM are compared with the analytical one,and the phase boundary obtained by NGM is found to be in good agreement with the theoretical prediction.Then,we use NGM to investigate the evolution of the Chern number in non-Hermitian samples with the disorder effect.For the square sample,the stability of the non-Hermitian Chern insulator under disorder is confirmed.Significantly,we obtain a nontrivial topological phase induced by disorder.This phase is understood as the topological Anderson insulator in non-Hermitian systems.Finally,the disordered phase transition in the cylindrical sample is also investigated.The clean non-Hermitian cylindrical sample has three phases,and such samples show more phase transitions by varying the disorder strength:(1)the normal insulator phase to the gapless phase,(2)the normal insulator phase to the topological Anderson insulator phase,and(3)the gapless phase to the topological Anderson insulator phase.

The coexistence of hermaphroditic and dioecious plants is associated with polyploidy and gender dimorphism in Dasiphora fruticosa

Dasiphora fruticosa comprises male,female and hermaphrodite plants,which are distributed sympatrically in some populations on the Qinghai-Tibet Plateau.To explore what governs the coexistence of these three sexual phenotypes,we investigated the DNA contents,pollen and ovule production,pollen deposition,and performed hand-pollination in both hermaphroditic and dioecious individuals of D.fruticosa.Flow cytometry confirmed that the DNA content of males and females were almost twice as much as that of the hermaphrodites.Male and female flowers produced more pollen grains and ovules than hermaphroditic flowers.Hand-pollinated treatments showed that unisexual flowers were sterile in one sexual function and bisexual flowers were fertile for both functions,but no sterile seeds were produced between unisexual and bisexual flowers.Our findings imply that polyploidy is related to gender dimorphism,and both are likely to play a strong role in the coexistence of two cryptic biological species of D.fruticosa(low ploidy hermaphroditic species and high ploidy dioecious species)in the Qinghai-Tibet Plateau.

Vertical direction impaction of kissing molars:A case report

BACKGROUND Kissing molars(KMs)are a scarcely reported form of molar impaction in which the occlusal surfaces contact each other within a single dental follicle and the roots point in opposite directions.The direction of KMs impaction is generally tilted.KMs with vertical direction impaction have not been reported in the literature.CASE SUMMARY A 25-year-old female visited a dentist for right maxillary wisdom teeth extraction and was diagnosed with two vertically impacted KMs in the left mandible on panoramic radiography.After cone-beam computed tomography examination confirmed no secondary complication,the patient chose to undergo observation and regular follow-up.A literature review of KMs revealed that vertical impacted KMs are rare;high-quality evidence regarding their prevalence is still lacking.At present,the causality of KMs is controversial.In this study,we have tried to provide a detailed definition of KMs to allow an accurate evaluation of their prevalence and classification based on their impaction direction which may be related to their pathogenesis.The treatment plan of KMs depends on the condition and location of the affected teeth and associated complications;they may be either directly extracted or treated using a multidisciplinary approach including maxillofacial surgeons and orthodontists.CONCLUSION KMs are a rare clinical condition of impacted teeth with unclear pathogenesis.Vertically impacted KMs were seldom reported.Reasonable definition and classification of KMs can help in the understanding of their causes and prevalence.

Predictive factors of visual function recovery after pituitary adenoma resection： a literature review and Meta-analysis

AIM：To determine the dominant predictive factors of postoperative visual recovery for patients with pituitary adenoma.METHODS：Pub Med,Google Scholar,Web of Science and Cochrane Library were searched for relevant human studies,which investigated the prediction of the postoperative visual recovery of patients with pituitary adenoma,from January2000 to May 2017.Meta-analyses were performed on the primary outcomes.After the related data were extracted by two independent investigators,pooled weighted mean difference（WMD）and odds ratio（OR）with 95%confidence interval（CI）were estimated using a random-effects or a fixed-effects model.RESULTS：Nineteen studies were included in the literature review,and nine trials were included in the Metaanalysis,which comprised 530 patients（975 eyes）with pituitary adenoma.For the primary outcomes,there was a significant difference between preoperative and postoperative mean deviation（MD）values of the visual field（WMD-5.85;95%CI：-8.19 to-3.51;P〈0.00001）.Predictivecharacteristics of four factors were revealed in this Metaanalysis by assigning the patients to sufficient and insufficient groups according to postoperative visual field improvements,including preoperative visual field defect（WMD 10.09;95%CI：6.17 to 14.02;P〈0.00001）,patient age（WMD-12.32;95%CI：-18.42 to-6.22;P〈0.0001）,symptom duration（WMD-5.04;95%CI：-9.71 to-0.37;P=0.03）,and preoperative peripapillary retinal nerve fiber layer（p RNFL）thickness（OR 0.1;95%CI：0.04 to 0.23;P〈0.00001）.CONCLUSION：Preoperative visual field defect,symptom duration,patient age,and preoperative p RNFL thickness are the dominant predictive factors of the postoperative recovery of the visual field for patients with pituitary adenoma.

Cell number explains the intraspecific spur-length variation in an Aquilegia species

Variations of nectar spur length allow pollinators to utilize resources in novel ways,leading to the different selective pressures on spurs and allowing taxa to diversify.However,the mechanisms underlying spur length variation remain unclear.Interspecific comparisons of spur length suggest that both cell division and anisotropic expansion could explain the changes of spur length,and that hormone-related genes contribute to the process of spur formation.In contrast,little is known about intraspecific spur length variation.In Aquilegia rockii,spur length varies strikingly,ranging from 1 mm to 18 mm.To examine the potential mechanisms underlying spur length variation in A.rockii,we observed cell morphology and analyzed RNA-seq of short-and long-spurred flowers.Scanning electron microscopy revealed that at two positions on spurs there were no differences in either cell density or cell anisotropy between short-and long-spurred flowers,suggesting that in A.rockii changes in cell number may explain variations in spur length.In addition,we screened transcriptomes of short-and long-spurred flowers for differentially expressed genes;this screen identified several genes linked to cell division(e.g.,F-box,CDKB2-2,and LST8),a finding which is consistent with our analysis of the cellular morphology of spurs.However,we did not find any highly expressed genes involved in the hormone pathway in long-spurred flowers.In contrast to previous hypotheses that anisotropic cell expansion leads to interspecific spur variation in Aquilegia,our results suggest that cell number changes and related genes are mainly responsible for spur length variations of A.rockii.Furthermore,the underlying mechanisms of similar floral traits in morphology may be quite different,enriching our understanding of the mechanisms of flower diversity in angiosperms.