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Mapping frontier molecular orbitals using photocurrents

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Science China Materials 2023年第9期66卷 3761-3762页

作者： Ping Zhou j.fraser Stoddart Hongliang Chen Stoddart Institute of Molecular Science Department of ChemistryZhejiang UniversityHangzhou 310027China ZjU-Hangzhou Global Scientific and Technological Innovation Center Zhejiang UniversityHangzhou 311215China Department of Chemistry Northwestern University2145 Sheridan RoadEvanstonIllinois 60208USA School of Chemistry University of New South WalesSydneyNSW 2052Australia

In the regime of coherent transport, the conductance of a molecular junction is governed(Fig. 1a) by the probability of electron transmission between the metal electrodes, a physica property which is affected significantly by the hybridization of frontier molecular orbitals(FMOs) with the continuous band of energy levels on the electrodes.

关键词： frontier molecular orbitals

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Making chiral molecular knots and links stereospecifically

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National Science Review 2023年第3期10卷 58-59页

作者： Huang Wu Chun Tang Long Zhang j.fraser Stoddart Department of Chemistry Northwestern University School of Chemistry University of New South Wales Stoddart Institute of Molecular Science Department of Chemistry Zhejiang University ZjU-Hangzhou Global Scientific and Technological Innovation Center

Topological structures [1,2],i.e.,knots and links,grace the macroscopic world in the form of biomorphs and artificial tools,all the way down to the molecular scale,such as catenated DNA and *** inherently exists in structures in which mirror-image topologies cannot be superimposed upon themselves without disassembling the topological *** the chirality we are most familiar with is based on stereogenic centers,

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Mechanisms underlying feed intolerance in the critically ill: Implications for treatment

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World journal of Gastroenterology 2007年第29期13卷 3909-3917页

作者： Adam Deane Marianne j Chapman Robert j fraser Laura K Bryant Carly Burgstad Nam Q Nguyen Intensive Care Unit Royal Adelaide Hospital Adelaide South Australia Discipline of Medicine University of Adelaide and Investigation and Procedures Unit Repatriation General Hospital Adelaide South Australia Investigation and Procedures Unit Repatriation General Hospital Adelaide South Australia Department of Gastroenterology and Hepatology Royal Adelaide Hospital Adelaide South Australia

Malnutrition is associated with poor outcomes in critically ill patients. Although nutritional support is yet to be proven to improve mortality in non-malnourished critically ill patients, early enteral feeding is considered best practice. However, enteral feeding is often limited by delayed gastric emptying. The best method to clinically identify delayed gastric emptying and feed intolerance is unclear. Gastric residual volume （GRV） measured at the bedside is widely used as a surrogate marker for gastric emptying, but the value of GRV measurement has recently been disputed. While the mechanisms underlying delayed gastric emptying require further investigation, recent research has given a better appreciation of the pathophysiology. A number of pharmacological strategies are available to improve the success of feeding. Recent data suggest a combination of intravenous metoclopramide and en/thromycin to be the most successful treatment, but novel drug therapies should be explored. Simpler methods to access the duodenum and more distal small bowel for feed delivery are also under investigation. This review summarises current understanding of the factors responsible for, and mechanisms underlying feed intolerance in critical illness, together with the evidence for current practices. Areas requiring further research are also highlighted.

关键词： Critical illness Enteral nutrition Gastric emptying Gastric motility Gastrointestinal hormones Metoclopramide Erythromycin Prokinetic therapy

Impact of bolus volume on small intestinal intra-luminal impedance in healthy subjects

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World journal of Gastroenterology 2010年第17期16卷 2151-2157页

作者： Nam Q Nguyen Laura K Bryant Carly M Burgstad Robert j fraser Daniel Sifrim Richard H Holloway Department of Gastroenterology & Hepatology Royal Adelaide HospitalAdelaide 5000Australia Investigation and Procedures Unit Repatriation General HospitalDaw Park 5041Australia Department of Medicine Centre for Gastroen-terological ResearchK.U.LeuvenLeuven 3000Belgium

AIM: To assess the impact of bolus volume on the characteristics of small intestinal (SI) impedance ***: Concurrent SI manometry-impedance measurements were performed on 12 healthy volunteers to assess the pattern of proximal jejunal fluid bolus movement over a 14 *** subject was given 34 boluses of normal saline (volume from 1 to 30 mL) via the feeding tube placed immediately above the proximal margin of the studied segment.A bolus-induced impedance event occurred if there was > 12% impedance drop from baseline,over ≥ 3 consecutive segments within 10 s of bolus injection.A minor or major imped-ance event was defined as a duration of impedance drop jor impedance events (≥ 10 mL boluses = 63%,3 mL boluses = 17%,and < 3 mL boluses = 0%,P = 0.02).CONCLUSION: Bolus volume had an impact on the type and length of propagation of SI impedance events and a threshold of 2 mL is required to produce an event.

关键词： Bolus volume Health Impedance Luminal flow Small intestine

Hydrogen-Bonded Organic Frameworks:A Rising Class of Porous Molecular Materials

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Accounts of Materials Research 2020年第1期1卷 77-87页

作者： Penghao Li Matthew R.Ryder j.fraser Stoddart Department of Chemistry Northwestern UniversityEvanstonIllinois 60208United States Neutron Scattering Division Oak Ridge National LaboratoryOak RidgeTennessee 37831United States Institute for Molecular Design and Synthesis Tianjin UniversityTianjin 300072China School of Chemistry University of New South WalesSydneyNSW 2052Australia

CONSPECTUS:Hydrogen-bonded organic frameworks(HOFs)are a class of porous molecular materials that rely on the assembly of organic building blocks by means of hydrogen-bonding interactions to form two-dimensional(2D)and three-dimensional(3D)crystalline *** reversible nature of the hydrogenbond formation endows HOFs with the attributes of solution processability and simple ***-quality single crystals of HOFs can be grown easily for unambiguous superstructure determination by single-crystal X-ray diffraction,which is crucial for the elucidation of superstructure−property *** the past decade,considerable progress has been achieved in realizing stable HOFs with permanent porosities by focusing on the design of molecular building blocks in order to introduce rigidity,auxiliary[π···π]interactions,and interpenetration of their frameworks to sustain the extended *** applications of HOFs are far-reaching,spanning catalysis,energy,and biomedical products as well as the storage and separation of fine *** this Account,we,first of all,provide an overview of the chronological development of HOFs,starting from the seminal work by Marsh and Duchamp in 1969 on the crystal superstructure of the hydrogen-bonded networks of trimesic *** identify the development of novel hydrogen-bonding motifs such as diaminotriazine(DTA),the introduction of the concept of molecular tectonics,and the establishment of permanent porosity in HOFs as being some of the milestones,which incentivized the current burgeoning research endeavors on developing HOFs as multifunctional *** Account is focused primarily on surveying the strategies for constructing porous 3D HOFs based on organic building blocks with peripheral carboxyl *** strategies are presented in the following categories:(1)the polycatenation of 2D networks by trigonal building blocks to form global 3D frameworks,(2)the utilization of building blocks with 3D geometrie

关键词： properties. bonding bonded

Eight decades of compositional change in a managed northern hardwood landscape

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Forest Ecosystems 2023年第3期10卷 398-410页

作者： Mark j.Ducey Olivia L.fraser Mariko Yamasaki Ethan P.Belair William B.Leak University of New Hampshire Department of Natural Resources and the Environment114 James HallDurhamNH03824USA U.S.D.A.Forest Service White Mountain National Forest71 White Mountain DriveCamptonNH03223USA U.S.D.A.Forest Service Northern Research Station271 Mast RoadDurhamNH03824USA The Nature Conservancy Natural Climate SolutionsAfrica Regional Portland Office45 Exchange StSuite 303PortlandME04101USA

We analyzed over 8 decades of change in forest composition(represented by species proportion of basal area)and size class from more than 400 permanent plots located on the Bartlett Experimental Forest in the White Mountains of New *** data represent one of the longest-term landscape-scale records of forest change based on permanent plots in North *** analyzed the plots based on elevation class,land type indicating assumed successional direction(grouped into coniferous and deciduous),and inventory period within managed and unmanaged portions of the *** ongoing shift from small-to large-diameter stems is clear across all species,in response to the overall aging of the forest following exploitative harvesting in the 19th *** compositional changes include a continuing decline in shade-intolerant species(paper birch and aspen),along with the mid-tolerant yellow *** increase in red maple abundance through the early 1990s has leveled off or *** shade-tolerant species,increases in beech and red spruce were largely consistent with assumed land type on unmanaged plots,but heavy marking against diseased beech on managed plots restricted increase of that *** maple declined in abundance except where silvicultural intervention helped maintain *** contrast,eastern hemlock showed a continuing expansion at all elevations below 600 *** data continue to show little or no evidence of upward migration of species,despite evidence of recent regional change in ***,the BEF is poised for substantial changes when emerald ash borer and hemlock woolly adelgid,both of which are known to infest nearby areas,do arrive.

关键词： Northern hardwoods Succession Stand dynamics Silviculture

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The Rise and Promise of Molecular Nanotopology

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CCS Chemistry 2021年第7期3卷 1542-1572页

作者： Qing-Hui Guo Yang jiao Yuanning Feng j.fraser Stoddart Department of Chemistry Northwestern UniversityEvanstonIL 60208 Stoddart Institute of Molecular Science Department of ChemistryZhejiang UniversityHangzhou 310027 ZjU-Hangzhou Global Scientific and Technological Innovation Center Hangzhou 311215 School of Chemistry University of New South WalesSydneyNSW 2052

Molecular nanotopology—a term we coined recently—is a rapidly developing field of research that is emerging out of the confluence of chemical topology with the mechanical *** perusing the increased research activities in this field,it is clear that a new discipline is ready to receive recognition in its own *** this Mini-Review,we address the historical development of chemical topology and describe how the rational design and practical synthesis of molecular links and knots with mechanical bonds.

关键词： chemical topology helicates interwoven grids mechanical bonds molecular knots molecular links nanoconfinement networks template synthesis topological chirality

Whither Second-Sphere Coordination?

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CCS Chemistry 2022年第3期4卷 755-784页

作者： Wenqi Liu Partha j.Das Howard M.Colquhoun j.fraser Stoddart Department of Chemistry Northwestern UniversityEvanstonIL 60208 Department of Chemistry University of ReadingReading RG66DX School of Chemistry University of New South WalesSydneyNSW 2052 Department of Chemistry Stoddart Institute of Molecular ScienceZhejiang UniversityHangzhou 310027 ZjU-Hangzhou Global Scientific and Technological Innovation Center Hangzhou 311215

The properties of coordination complexes are dictated by both the metals and the *** use of molecular receptors as second-sphere ligands enables significant modulation of the chemical and physical properties of coordination *** this minireview,we highlight recent advances in functional systems based on molecular receptors as second-sphere coordination ligands,as applied in molecular recognition,synthesis of mechanically interlocked molecules,separation of metals,catalysis,and biomolecular *** functional systems demonstrate that second-sphere coordination is an emerging and very promising strategy for addressing societal challenges in health,energy,and the environment.

关键词： catalysis coordination complexes mechanically interlocked molecules metal recovery molecular recognition supramolecular chemistry

Barriers and facilitators to participating in cardiac rehabilitation and physical activity:A cross-sectional survey

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World journal of Cardiology 2022年第2期14卷 83-95页

作者： Matthew james fraser Stephen j Leslie Trish Gorely Emma Foster Ronie Walters Division of Biomedical Science University of the Highlands and IslandsInverness IV23JHUnited Kingdom Department of Cardiology NHS HighlandInverness IV23UJUnited Kingdom Department of Nursing and Midwifery University of the Highlands and IslandsInverness IV23JHUnited Kingdom Cardiac Unit NHSH NHS HighlandInverness IV23JHUnited Kingdom

BACKGROUND Cardiovascular diseases(CVD)have been shown to be the greatest cause of death worldwide and rates continue to *** is recommended that CVD patients attend cardiac rehabilitation(CR)following a cardiac event to reduce mortality,improve recovery and positively influence behaviour around CVD risk *** the recognised benefits and international recommendations for exercisebased CR,uptake and attendance remain suboptimal.A greater understanding of CR barriers and facilitators is required,not least to inform service *** understanding current cardiac patients’attitudes and opinions around CR and physical activity(PA)could inform patient-led ***,through understanding aspects of CR and PA that participants like/dislike could provide healthcare providers and policy makers with information around what elements to target in the *** To investigate participants’attitudes and opinions around CR and *** This study employed a cross-sectional survey design on 567 cardiac *** patients who were referred for standard CR classes at a hospital in the Scottish Highlands,from May 2016 to May 2017 were *** part of a larger survey,the current study analysed the free-text responses to 5 open-ended questions included within the wider *** were related to the participants’experience of CR,reasons for non-attendance,ideas to increase attendance and their opinions on *** data were analysed using a 6-step,reflexive thematic *** Two main topic areas were explored:“Cardiac rehabilitation experience”and“physical activity”.Self-efficacy was increased as a result of attending CR due to exercising with similar individuals and the safe environment *** ranged from age and health to distance and starting times of the classes which increased travel time and ***,responses demonstrated a lack of information and communication around the *** h

关键词： Cardiovascular disease Cardiac rehabilitation Physical activity Barriers Facilitators Patient experience