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canopy gap size influences niche partitioning of the ground-layer plant community in a northern temperate forest

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Journal of Plant Ecology 2013年第1期6卷 92-100页

作者： christel c.Kern rebecca A.Montgomery Peter B.Reich Terry F.Strong USDA Forest Service Northern Research Station1831 Hwy 169 EastGrand RapidsMN 55744USA Department of Forest Resources University of Minnesota-Twin Cities1530 North Cleveland AvenueSaint PaulMN 55108USA Hawkesbury Institute for the Environment University of Western SydneyLocked Bag 1797Penrith NSW 2751Australia USDA Forest Service USARetired

Aims The Gap Partitioning Hypothesis(GPH)posits that gaps create heterogeneity in resources crucial for tree regeneration in closed-canopy forests,allowing trees with contrasting strategies to coexist along resource *** studies have examined gap partitioning of temperate,ground-layer vascular *** used a ground-layer plant community of a temperate deciduous forest in northern Wisconsin,USA,as a model system to test whether the GPH extends to the relatively species-rich ground *** We used a well-replicated experimental approach that included a gap opening gradient(five gap sizes,6,10,20,30 and 46 m diameter,and undisturbed reference areas),a within-gap location gradient(gap edge to center),and a temporal gradient(0,2,6 and 13 years after gap creation).The data were observations of ground-layer plant abundance,published plant traits,and a modeled index of understory light *** ordinated the plant abundance data and evaluated the relationships of composition,traits and light environment by gap size,location along the forest-gap transect and time,with several approaches such as correlations,descriptive statistics,non-parametric tests of group differences and indicator species importance *** Findings Ground-layer plant composition and traits differed across gap sizes,within-gap locations and over *** of all sizes differed in composition from undisturbed areas,and all pair-wise combinations of gap size also differed in composition,except the 6 m from the 10-m *** gaps(46 m)also displayed within-gap compositional gradients from gap edge to center *** differences in gap size were evident 2 years after gap creation and,contrary to our hypotheses,remained different over the 13-year period,even in gaps with crown *** contrast to the neutral theory,species functional traits and microenvironmental conditions were related to variation in ground-layer *** with smaller seeds,low

关键词： herbaceous layer experimental gaps proximity to edge functional diversity plant traits

Seeing red: color vision in the largemouth bass

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current Zoology 2019年第1期65卷 43-52页

作者： Lisa D. MiTcHEM Shannon Stanis Muchu Zhou Ellis LoEw John M. Epifanio rebecca c. Fuller Department of Animal Biology School of Integrative Biology University of Illinois Champaign IL 61820 USA Department of Biomedical Sciences and Section of Physiology College of Veterinary Medicine Cornell University Ithaca NY 14853 USA Illinois Natural History Survey Champaign IL 61820 USA

How animals visually perceive the environment is key to understanding important ecological behaviors, such as predation, foraging, and mating. This study focuses on the visual system properties and visual perception of color in the largemouth bass Micropterus salmoides. This study (1) documents the number and spectral sensitivity of photoreceptors,(2) uses these parameters to model visual perception, and (3) tests the model of color perception using a behavioral assay. Bass possess single cone cells maximally sensitive at 535 nm, twin cone cells maximally sensitive at 614 nm, and rod cells maximally sensitive at 528 nm. A simple model of visual perception predicted that bass should not be able to discern between chartreuse yellow and white nor between green and blue. In contrast, bass should be able to discern red from all achromatic (i.e., gray scale) stimuli. These predictions were partially upheld in behavioral trials. In behavioral trials, bass were first trained to recognize a target color to receive a food reward, and then tested on their ability to differentiate between their target color and a color similar in brightness. Bass trained to red and green could easily discern their training color from all other colors for target colors that were similar in brightness (white and black, respectively). This study shows that bass possess dichromatic vision and do use chromatic (i.e., color) cues in making visual-based decisions.

关键词： bass cones photoreceptors rods vision

Sequence analysis of peptides with biological activities using electrospray-Fourier transform ion cyclotron resonance mass spectrometry

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chinese Science Bulletin 2001年第15期46卷 1281-1285页

作者： HE Meiyu XU Jiaxi HE Xiaoran Tak Wah Dominic chan rebecca L.c.Lau Department of chemistry Peking UniversityBeijing 100871China Beijing Mass Spectrometry center Beijing 100080China Department of chemistry The Chinese University of Hong KongShatinN.T.Hong KongChina

The mass spectra of five peptides with biological activities are reported. All mass spectra were recorded using a 4.7-T Fourier transform ion cyclotron resonance mass spectrometer equipped with an external electrospray source. The accurate molecular weights for the five peptides prepared by solid phase synthesis were measured as 1765.9013, 1063.5420, 1092.5254, 820.3804 and 1078.5193, respectively. All the data were obtained with the external calibration. Differences between observed and theoretical monoisotopic molecular weights were in the (0.2-1.0)×10-6 range. The complete primary sequence for the five polypep-tides were determined using the method of in-source electrospray ionization/collision induced dissociation (ESI/cID). All the intact y series ions and b series ions were obtained from various peptides respectively, thus determining the sequences of the five polypeptides. We found that the meas-ured accurate molecular mass of sample 4 was not in agreement with that expected from the planned

关键词： sequence peptide with biological activity Fourier transform ion cyclotron resonance mass spectrometry electrospray collision-induced dissociation.

Grand challenge in Biomaterials-wound healing

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Regenerative Biomaterials 2016年第2期3卷 127-128页

作者： Joseph c.Salamone Ann Beal Salamone Katelyn Swindle-Reilly Kelly Xiaoyu-chen Leung rebecca E.McMahon Rochal Industries LLc 12719 Cranes MillSan AntonioTX78230USA Department of Biomedical Engineering The Ohio State UniversityColumbus OH 43210USA

Providing improved health care for wound,burn and surgical patients is a major goal for enhancing patient well-being,in addition to reducing the high cost of current health care *** introduction of new and novel biomaterials and biomedical devices is anticipated to have a profound effect on the future improvement of many deleterious health *** publication will discuss the development of novel non-stinging liquid adhesive bandages in healthcare applications developed by Rochal *** scientists/engineers at Rochal have participated in commercializing products in the field of ophthalmology,including rigid gas permeable contact lenses,soft hydrogel contact lenses,silicone hydrogel contact lenses,contact lens care solutions and cleaners,intraocular lens materials,intraocular controlled drug delivery,topical/intraocular anesthesia,and in the field of wound care,as non-stinging,spray-on liquid bandages to protect skin from moisture and body fluids and medical adhesive-related skin *** areas of entrepreneurial activity at Rochal Industries pertain to the development of new classes of biomaterials for wound healing,primarily in regard to microbial infection,chronic wound care,burn injuries and surgical procedures,with emphasis on innovation in product creation,which include cell-compatible substrates/scaffolds for wound healing,antimicrobial materials for opportunistic pathogens and biofilm reduction,necrotic wound debridement,scar remediation,treatment of diabetic ulcers,amelioration of pressure ulcers,amelioration of neuropathic pain and adjuvants for skin tissue substitutes.

关键词： non-stinging liquid adhesive bandages

contemporary approaches to visual prostheses

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Military Medical Research 2019年第3期6卷 254-262页

作者： rebecca M.Mirochnik John S.Pezaris Department of Bioengineering Northeastern UniversityBostonMAUSA Department of Neurosurgery Massachusetts General HospitalBostonMAUSA.3Department of NeurosurgeryHarvard MedicalSchoolBostonMAUSA.

Visual prostheses serve to restore visual function following acquired blindness. Acquired blindness(as opposed to congenital blindness) has many causes, including diseases such as retinitis pigmentosa, glaucoma, and macular degeneration, or trauma such as caused by automobile accident or blast damage from explosions. Many of the blindness-causing diseases target the retina or other ocular structure. Often, despite the loss of sensitivity to light, the remainder of the visual pathway is still functional, enabling electrical devices to deliver effective and meaningful visual information to the brain via arrays of electrodes. These arrays can be placed in any part of the early visual pathway, such as the retina, optic nerve, lateral geniculate nucleus, or visual cortex. A camera or other imaging source is used to drive electrical stimulation of remaining healthy cells or structures to create artificial vision and provide restoration of function. In this review, each approach to visual prostheses is described, including advantages and disadvantages as well as assessments of the current state of the art. Most of the work to-date has been targeting stimulation of(a) the retina, with three devices approved for general use and two more in clinical testing;(b) the lateral geniculate nucleus, with efforts still in the pre-clinical stage;and(c) the cortex, with three devices in clinical testing and none currently approved for general use despite the longest history of investigation of the three major approaches. Each class of device has different medical indications, and different levels of invasiveness required for implantation. All contemporary devices deliver relatively poor vision. There has been remarkable progress since the first proof-ofconcept demonstration that used stimulation of the primary visual cortex, with the field exploring all viable options for restoration of function. Much of the progress has been recent, driven by advances in microelectronics and biocompat

关键词： Visual prosthesis Blindness Artificial vision

changing the paradigm：the potential for targeted therapy in laryngeal squamous cell carcinoma

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cancer Biology & Medicine 2016年第1期13卷 87-100页

作者： Megan L.Ludwig Andrew c.Birkeland rebecca Hoesli Paul Swiecicki Matthew E.Spector J.chad Brenner Department of Otolaryngology Head and Neck SurgeryUniversity of Michigan Medical SchoolAnn ArborMI 48109USA cellular and Molecular Biology Program University of MichiqanAnn ArborMI 48109USA Department of Hematology Oncology University of Michigan Medical SchoolAnn ArborMI 48109USA comprehensive cancer center University of Michigan Medical SchoolAnn ArborMI 48109USA

Laryngeal squamous cell carcinoma(LScc) remains a highly morbid and fatal disease. Historically, it has been a model example for organ preservation and treatment stratification paradigms. Unfortunately, survival for LScc has stagnated over the past few decades. As the era of next-generation sequencing and personalized treatment for cancer approaches, LScc may be an ideal disease for consideration of further treatment stratification and personalization. Here, we will discuss the important history of LScc as a model system for organ preservation, unique and potentially targetable genetic signatures of LScc, and methods for bringing stratified, personalized treatment strategies to the 21^(st) century.

关键词： Head and neck cancer laryngeal squamous cell carcinoma genetics targeted therapy personalized medicine

Effects of elevated [cO_2] on stem and root lodging among rice cultivars

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chinese Science Bulletin 2013年第15期58卷 1787-1794页

作者： ZHU chunWu cHENG WeiGuo SAKAI Hidemitsu OIKAWA Shimpei LAZA rebecca c USUI Yasuhiro HASEGAWA Toshihiro National Institute for Agro-Environmental Sciences Ibaraki 305-8604Japan Faculty of Agriculture Yamagata UniversityYamagata 997-8555Japan Faculty of International Agriculture and Food Studies Tokyo University of AgricultureTokyo 156-8502Japan crop and Environmental Sciences Division International Rice Research InstituteDAPO Box 7777Metro ManilaPhilippines

Studies showed that elevated [cO2] would improve photosynthetic rates and enhance yields of rice;however,few studies have focused on the response of rice lodging,which is a major cause of cereal yield loss and quality reduction,under elevated [cO2].In this study,we examined the effects of elevated [cO2] on stem and root lodging using 4 rice cultivars(86Y8,japonica hybrid;LYP9,2-line indica hybrid;variety 9311,type of indica inbred rice,and SY63,3-line indica hybrid) grown under two [cO2] levels:400 and 680 μmol *** results indicated that under elevated [cO2],the stem-lodging risk(SLR) of 9311 decreased,while in SY63 the SLR increased,86Y8 and LYP9 were not significantly affected;the risk of root lodging was reduced for all cultivars,because root biomass(instead of root number) and bending strength were increased significantly,and then the increase of anti-lodging ability is far higher than that of self-weight mass moment for all *** findings suggested that higher [cO2] can enhance the risk of stem-lodging for cultivars with strong-[cO2]-responses,but may not aggravate the root lodging for all rice cultivars.

关键词： cO2浓度升高倒伏水稻品种间种茎二氧化碳浓度升高水稻品种杂交粳稻两优培九

Akt3 promotes cancer stemness in triple-negative breast cancer through YB1-Snail/Slug signaling axis

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Genes & Diseases 2023年第2期10卷 301-306页

作者： Ye Tian Jiang Li Tsz chung cheung Vincent Tam c. Geoffrey Lau Xin Wang Y.rebecca chin Tung Biomedical Sciences centre Department of Biomedical SciencesCity University of Hong KongKowloonHong Kong SARChina Department of Neuroscience City University of Hong KongKowloonHong Kong SARChina city University of Hong Kong Shenzhen Research Institute ShenzhenGuangdong 518057China Department of Surgery The Chinese University of Hong KongShatinHong Kong SARChina

Dear Editor,Triple-negative breast cancer(TNBc)is an aggressive breast cancer subtype enriched in cancer stem cells(cScs),which is characterized by high malignancy and drug resistance.1 The PI3K/Akt signaling cascade is frequently hyperactivated in *** and non-redundant functions of the three Akt isoforms in tumorigenesis,however,have not been studied *** is noteworthy that despite a few isoform-specific substrates have been identified for Akt1 and Akt2,an Akt3-specific substrate is yet to be *** have previously shown that overexpression of Akt3,but not Akt1 or Akt2,plays an essential role in TNBc growth and therapeutic resistance of breast cancer.2 However,the role of Akt3 in TNBc cScs remains unclear.

关键词： Akt1 breast Akt3

SLc11A1 polymorphisms in inflammatory bowel disease and Mycobacterium avium subspecies paratuberculosis status

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World Journal of Gastroenterology 2010年第45期16卷 5727-5731页

作者： Lucy c Stewart Andrew S Day John Pearson Murray L Barclay Richard B Gearry rebecca L Roberts Robert W Bentley Department of Paediatrics University of OtagoChristchurch 8140New Zealand Department of Paediatrics Christchurch HospitalChristchurch 8140New Zealand Department of Pathology University of OtagoChristchurch 8140New Zealand Department of Medicine University of OtagoChristchurch 8140New Zealand Department of Gastroenterology Christchurch HospitalChristchurch 8140New Zealand Department of Biochemistry University of OtagoDunedin 9054New Zealand

AIM: To test for association of SLc11A1 with inflammatory bowel disease (IBD) and Mycobacterium avium subspecies paratuberculosis (MAP) status in a caucasian cohort. METHODS: Five hundred and seven crohn's disease (cD) patients, 474 ulcerative colitis (Uc) patients, and 569 healthy controls were genotyped for SLc11A1 1730G>A and SLc11A1 469+14G>c using pre-designed TaqMan  SNP assays. χ 2 tests were applied to test for association of single nucleotide polymorphisms (SNPs) with disease, and the presence of MAP ***:SLc11A1 1730G>A and SLc11A 1469+14G>c were not associated with cD, Uc, or IBD. The SLc11A1 1730A minor allele was over-represented in patients who did not require immunomodulator therapy (P = 0.002, OR: 0.29, 95% cI: 0.13-0.66). The frequency of the SLc11A1 469+14c allele was higher in the subset of study participants who tested positive for MAP DNA (P = 0.02, OR: 1.56, 95% cI: 1.06-2.29). No association of SLc11A1 1730G>A with MAP was ***: Although SLc11A1 was not associated with IBD, association with MAP suggests that SLc11A1 is important in determining susceptibility to bacteria implicated in the etiology of cD.

关键词： NRAMP1 crohn’s disease Ulcerative colitis IS900 polymerase chain reaction