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Silk-based nerve guidance conduits with macroscopic holes modulate the vascularization of regenerating rat sciatic nerve

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Neural Regeneration Research 2025年第6期20卷 1789-1800页

作者： Carina Hromada Patrick Heimel Markus Kerbl Lászlógál Sylvia Nürnberger Barbara Schaedl james Ferguson Nicole Swiadek Xavier Monforte Johannes C.Heinzel Antal Nógrádi Andreas H.Teuschl-Woller David Hercher Department Life Science Engineering University of Applied Sciences Technikum WienViennaAustria Austrian Cluster for Tissue Regeneration ViennaAustria Ludwig Boltzmann Institute for Traumatology The Research Center in Cooperation with AUVAViennaAustria University Clinic of Dentistry Medical University of ViennaViennaAustria Department of Plastic Reconstructive and Aesthetic SurgeryLandesklinikum Wiener Neustadt2700 Wiener NeustadtAustria Department of Anatomy Histology and EmbryologyAlbert Szent-Györgyi Medical SchoolUniversity of SzegedSzegedHungary Medical University of Vienna Department of Orthopedics and Trauma SurgeryDevision of Trauma SurgeryViennaAustria Department of Hand- PlasticReconstructive and Burn SurgeryBG Unfallklinik TuebingenUniversity of TuebingenTuebingenGermany

Peripheral nerve injuries induce a severe motor and sensory deficit. Since the availability of autologous nerve transplants for nerve repair is very limited, alternative treatment strategies are sought, including the use of tubular nerve guidance conduits(tNgCs). However, the use of tNgCs results in poor functional recovery and central necrosis of the regenerating tissue, which limits their application to short nerve lesion defects(typically shorter than 3 cm). given the importance of vascularization in nerve regeneration, we hypothesized that enabling the growth of blood vessels from the surrounding tissue into the regenerating nerve within the tNgC would help eliminate necrotic processes and lead to improved regeneration. In this study, we reported the application of macroscopic holes into the tubular walls of silk-based tNgCs and compared the various features of these improved silk^(+) tNgCs with the tubes without holes(silk^(–) tNgCs) and autologous nerve transplants in an 8-mm sciatic nerve defect in rats. Using a combination of micro-computed tomography and histological analyses, we were able to prove that the use of silk^(+) tNgCs induced the growth of blood vessels from the adjacent tissue to the intraluminal neovascular formation. A significantly higher number of blood vessels in the silk^(+) group was found compared with autologous nerve transplants and silk^(–), accompanied by improved axon regeneration at the distal coaptation point compared with the silk^(–) tNgCs at 7 weeks postoperatively. In the 15-mm(critical size) sciatic nerve defect model, we again observed a distinct ingrowth of blood vessels through the tubular walls of silk^(+) tNgCs, but without improved functional recovery at 12 weeks postoperatively. Our data proves that macroporous tNgCs increase the vascular supply of regenerating nerves and facilitate improved axonal regeneration in a short-defect model but not in a critical-size defect model. This study suggests that further optimizatio

关键词： axon regeneration blood vessel functional recovery macroporous nerve lesion peripheral nerve repair sciatic nerve silk-based nerve guidance conduit vascularization

Photoluminescence properties of a novel orange-red emitting Ba_2CaZn_2Si_6O_(17):Sm^(3+)phosphor

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Journal of Rare Earths 2016年第6期34卷 576-582页

作者： g.Annadurai S.Masilla Moses kennedy V.Sivakumar Department of Physics S.S.N.College of EngineeringRajiv Gandhi SalaiKalavakkam-603 110ChennaiTamil NaduIndia Saveetha Engineering College Thandalam-602105ChennaiIndia

Novel orange-red emitting Ba_2Ca_（1–x）Zn_2Si_6O_（17）：x Sm^（3＋）（0.02≤x≤0.08） phosphors were synthesized using conventional solid-state reaction method under air atmosphere. The phase formation of the samples was characterized by powder X-ray diffraction patterns. Scanning electron microscopy（SEM） and photoluminescence properties were also investigated. The narrow excitation and emission spectra indicated the typical 4f-4f transitions of Sm^（3＋）. The dominant excitation line was around 405 nm attributed to ~6H_（5/2）→ ~4F_（7/2） and the emission spectrum consisted of four emission peaks at 562, 600, 647, and 708 nm corresponding to the various transitions ~4g_（5/2） to ~6HJ（J=5/2, 7/2, 9/2 and 11/2） of the Sm^（3＋） ions in the same order. The strongest emission band located at 600 nm was attributed to ~4g_（5/2）→~6H_（7/2） transition of Sm^（3＋）, producing bright orange-red color emission. The optimal dopant concentration of Sm3＋ ion in Ba_2CaZn_2Si_6O_（17）：x Sm^（3＋） phosphor was around 4 mol.% and the critical transfer distance（Rc） of Sm^（3＋） was calculated to be 2.65 nm. Decay time varied with the Sm^（3＋） concentrations in Ba_2 CaZn_2Si_6O_（17） phosphors. In addition, the Commission International del＇Eclairagethe（CIE） chromaticity coordinates of Ba_2Ca_（0.96）Zn_2Si_6O_（17）：0.04Sm^（3＋） phosphor was located in the orange-red region（0.547, 0.450） and the correlated color temperature（CCT） was 2543 K. The present results indicated that Sm^（3＋） activated Ba_2CaZn_2Si_6O_（17） phosphors may be used as an orange-red emitting phosphor for near-ultraviolet（n-UV） based white light emitting diodes（WLEDs） applications.

关键词： Sm^(3+) phosphors photoluminescence WLEDs rare earths

Alignment of the hindfoot following total knee arthroplasty: A systematic review

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World Journal of Orthopedics 2021年第10期12卷 791-801页

作者： james J Butler Nathaniel P Mercer Eoghan T Hurley Mohammad T Azam John g kennedy Department of Orthopedic Surgery Royal College Surgeons in IrelandDublin 18Ireland Department of Orthopedic Surgery NYU Langone HealthNew YorkNY 10002United States

BACKgROUND There appears to be a close relationship between deformities at the knee joint and at the hindfoot in patients with knee osteoarthritis(OA).Despite this intrinsic link,there is a dearth of studies investigating alterations in hindfoot alignment following total knee arthroplasty(TKA)in patients with knee *** To evaluate changes in alignment of the hindfoot following TKA,foot and ankle clinical outcomes in terms of subjective clinical scoring tools following surgical intervention,and to analyse the level of evidence(LOE)and quality of evidence(QOE)of the included *** MEDLINE,EMBASE and Cochrane Library databases were systematically reviewed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses *** reporting changes in the postoperative alignment of the hindfoot following TKA were *** level and QOE were recorded and *** Eleven studies with a total of 1142 patients(1358 knees)met the inclusion/exclusion *** studies were of LOE II and 5 studies were of LOE *** with preoperative varus knee deformity and valgus hindfoot deformity demonstrated improvement in hindfoot alignment post *** with preoperative varus knee deformity and varus hindfoot deformity demonstrated no improvement in hindfoot alignment following *** different radiographic parameters were used to measure the alignment of the hindfoot across the included studies,with the tibio-calcaneal angle most frequently utilised(27.3%).CONCLUSION This systematic review demonstrated that the hindfoot may display compensatory changes in alignment following TKA in patients with knee ***,the marked heterogeneity between the included studies and poor QOE limits any meaningful cross sectional comparisons between ***,well designed studies are necessary to determine the changes and outcomes of hindfoot alignment following TKA.

关键词： Total knee arthroplasty Hindfoot alignment Hindfoot Knee osteoarthritis Varus knee deformity Valgus hindfoot deformity

The Mysterious Mid-Carnian “Wet Intermezzo” global Event

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Journal of Earth Science 2015年第2期26卷 181-191页

作者： james g.Ogg Department of Earth Atmospheric and Planetary Sciences Purdue University Key Laboratory of Biogeology and Environmental geology of Ministry of Education China University of Geosciences

Approximately 230 million years ago in the middle of the Carnian stage of the Upper Triassic, the sedimentary records in different regional basins display dramatic changes. Tropical carbonate platforms abruptly ended, and engorged river systems left widespread sand-rich layers across inland basins and coastal regions. This pulse lasted less than a million years in some basins, but constituted a permanent shift in others. Following this event, the Late Carnian has the earliest record of significant dinosaurs on land and the emergence of the calcareous nannoplankton in the oceans that now govern Earth＇s carbon cycle. This ＂most distinctive climate change within the Tri- assic＂ has been interpreted by some geoscientists as a global disruption of the Earth＇s land-ocean-biological system. The eruption of the Wrangellia large igneous province may have been the trigger for a sudden carbon-dioxide-induced warming and associated increased rainfall in some of these regions. Indeed, some workers have proposed that this ＂wet intermezzo＂ warming event is a useful analog to aid in predicting the effects of our future greenhouse on land ecosystems and ocean chemistry. However, the understanding of the onset, duration, global impacts and relatively rapid termination of this postulated warming pulse has been hindered by lack of a global dataset with inter-calibrated terrestrial and marine biostratigraphy, precise radio-isotopic ages, stable isotope records of temperature and the carbon system, and cycle-calibrated rates of regional and global change.

关键词： Triassic Carnian climate pluvial Wrangellia carbon isotope excursion dolomite China LIP Yangtze Platform Wet Intermezzo large igneous province.

Production Process and Properties of a Highly Porous Al Alloy Made Using NaCl Droplets as a Space Holder

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Acta Metallurgica Sinica(English Letters) 2015年第8期28卷 1034-1040页

作者： Manuela Covaciu Andrew Richard kennedy Faculty of Engineering University of Nottingham Faculty of Material Science and Engineering Universitatea Tehnica din Cluj-Napoca School of Engineering Pontificia Universidad Católica de Chile

Porous Al structures have been made using a porogen leaching method but with additional novel steps. In this way, Al-0.25Cu-0.6Si-1.0Mg alloys with interconnected, open cells have been made, with high levels of porosity（up to 89%）. The use of 4 to 5 mm diameter sodium chloride droplets combined with interspersion of the metal powder and droplets in the die and dissolution of the salt before sintering was found to enable easier interspersion of the two components, resulting in good connectivity of the beads via the formation of ‘‘windows＇＇ between the pores, and rapid elimination of salt from the structure. Porous Al with densities in the range of 0.28–0.86 g/cm3 exhibited compressive yield strengths in the range of 0.14 to 7.5 MPa, with no difference being observed between the samples made by this route and by more conventional dissolution of the salt after sintering. These novel steps widen the possibility for porous metal manufacture to other materials, not limited by the need to have a sintering temperature below that for the melting point of salt.

关键词： Aluminium alloy Sodium chloride Porous metal

Irritable bowel syndrome: A microbiome-gut-brain axis disorder?

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World Journal of gastroenterology 2014年第39期20卷 14105-14125页

作者： Paul J kennedy John F Cryan Timothy g Dinan gerard Clarke 1.15 Biosciences Institute Department of Psychiatry Alimentary Pharmabiotic Centre University College Cork Cork Ireland Department of Anatomy and Neuroscience Alimentary Pharmabiotic CentreUniversity College CorkCork Ireland

Irritable bowel syndrome(IBS) is an extremely prevalent but poorly understood gastrointestinal disorder. Consequently, there are no clear diagnostic markers to help diagnose the disorder and treatment options are limited to management of the symptoms. The concept of a dysregulated gut-brain axis has been adopted as a suitable model for the disorder. The gut microbiome may play an important role in the onset and exacerbation of symptoms in the disorder and has been extensively studied in this context. Although a causal role cannot yet be inferred from the clinical studies which have attempted to characterise the gut microbiota in IBS, they do confirm alterations in both community stability and diversity. Moreover, it has been reliably demonstrated that manipulation of the microbiota can influence the key symptoms, including abdominal pain and bowel habit, and other prominent features of IBS. A variety of strategies have been taken to study these interactions, including probiotics, antibiotics, faecal transplantations and the use of germ-free animals. There are clear mechanisms through which the microbiota can produce these effects, both humoral and neural. Taken together, these findings firmly establish the microbiota as a critical node in the gut-brain axis and one which is amenable to therapeutic interventions.

关键词： Irritable bowel syndrome Microbiome Anxiety Tryptophan Abdominal pain gastrointestinal motility Cognition

Compressing local atomic neighbourhood descriptors

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npj Computational Materials 2022年第1期8卷 1593-1605页

作者： james P.Darby james R.Kermode gábor Csányi Engineering Dept University of CambridgeTrumpington StCambridgeCB21PZUK Warwick Centre for Predictive Modelling School of EngineeringUniversity of WarwickCoventryCV47ALUK

Many atomic descriptors are currently limited by their unfavourable scaling with the number of chemical elements S *** length of body-ordered descriptors,such as the SOAP power spectrum(3-body)and the(ACE)(multiple body-orders),scales as(NS)^(ν)whereν+1 is the body-order and N is the number of radial basis functions used in the density *** introduce two distinct approaches which can be used to overcome this scaling for the SOAP power ***,we show that the power spectrum is amenable to lossless compression with respect to both S and N,so that the descriptor length can be reduced from O(N^(2)S^(2))to O(NS).Secondly,we introduce a generalised SOAP kernel,where compression is achieved through the use of the total,element agnostic density,in combination with radial *** ideas used in the generalised kernel are equally applicably to any other body-ordered descriptors and we demonstrate this for the(ACSF).

关键词： SOAP scaling kernel

An antibody present in everybody that attacks malaria infected erythrocytes

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Journal of Biomedical Science and Engineering 2013年第7期6卷 1-3页

作者： james kennedy Manatee Memorial Hospital Bradenton USA

These malaria targeting antibodies are band 3 antibodies and they recognize a special configuration of a molecule called band 3 that is present on erythrocytes. The special band 3 configuration is present on the surface of senescent erythrocytes, malaria infected erythrocytes, the erythrocytes of certain hemoglobinnopathies such as sickle cell disease and on the erythrocytes of some metabolic disorders such as g6PD. Note that these hemoglobinopathies and metabolic disorders all aid in the survival of falciparum malaria to such an extent that their incidence is increased in falciparum endemic areas [1-3]. Though there are many adhesive molecules involved in the pathology of falciparum malaria and sickle cell anemia, the focus here is on the band 3 molecules.

关键词： Band 3 Malaria Sickle

The decision-making dimension of the systems approach to management

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Chinese Business Review 2010年第2期9卷 27-33页

作者： james kennedy Turkson School of Business Kwame Nkrumah University of Science and Technology Kumasi 00233 Ghana

Theoretically, a system is anything that is made up of various parts. Theses parts are known as subsystems. At every point in time, these parts should work in harmony so that objectives could be achieved successfully. A system could be inanimate or animate item. Examples of inanimate systems include vehicles, households, computer and institution. Examples of animate systems are human being, animal and insect. Both inanimate and animate systems are made up of various subsystems. Such subsystems are required to co-operate, collaborate and work together so that set objectives could be achieved successfully. From practical managerial point of view, business organizations are equally systems that are made up of subsystems which may take the form of departments, sections and/or units. It is supposed to be collaborations among the managers and other members in these departments, sections and/or units so that organizational objectives could be achieved. All the managers in various departments, sections and/or units are required to work together as a team to make the system coherent and closely-knit to make disintegration impossible. Closely related to the systems approach to management is managerial decision-making. Decision-making is a very important function of every manager＇s job. The success and failure stories of many organizations are the result of the quality of decisions made. Many organizations have survived turbulent conditions. Others have also collapsed in spite of favourable conditions. These varying conditions are the result of the quality of decisions made by managers at positions of authority and responsibility. Therefore the systems approach to management enjoins top managers in particular to be very circumspect and cautious in certain decision-making activities. This is because, the quality of decision a manager makes can go a long way to determine the success or failure story of an organization as exemplified in the case study in this paper.

关键词： system sub-system synergy open-system closed-system management decision-making