5,835 research outputs found
Intra-articular hyaluronic acid following knee immobilisation for 6 weeks in rabbits.
No full textThirty-two mature female New Zealand White rabbits were immobilised in an aluminium splint on one knee, using the contralateral non-treated knee as control. After 6 weeks the splints were removed and the rabbits allowed unrestricted movement. On a random basis, 16 rabbits were given an intra-articular injection of 5 mg in 0.5 ml of hyaluronic acid (HA) in the knee of the immobilised hindlimb at weekly intervals for 6 weeks, starting 1 week after the joint had been remobilised, for a total of six injections. In the other 16 rabbits no further intervention was conducted. At the end of the experiment the rabbits were killed, the area of degenerated joint surface of the distal femur, and water and proteoglycan content were measured, and the articular cartilage stained with haematoxylin and eosin and safranin O. Remobilisation without HA administration resulted in a significantly larger degenerated joint surface area. By the end of the experiment both remobilisation and remobilisation and intra-articular HA injections had produced a greater but non-significant water cartilage content compared to the control side. The average cartilage glycosaminoglycan content of the remobilisation and intra-articular HA injection group was significantly greater than in the remobilisation group. In conclusion, in the rabbits with one knee immobilised for 6 weeks, 6 weeks of remobilisation alone are not sufficient to recover from the moderate articular surface changes produced, and the intra-articular administration of HA may produce a morphologically and biochemically more normal cartilage. More extensive animal and human studies should be performed before the routine use of intra-articular administration of HA following musculoskeletal injuries that required immobilisation can be recommended
Detecting referral and selection bias by the anonymous linkage of practice, hospital and clinic data using Secure and Private Record Linkage (SAPREL): case study from the evaluation of the Improved Access to Psychological Therapy (IAPT) service.
No full textBACKGROUND: The evaluation of demonstration sites set up to provide improved access to psychological therapies (IAPT) comprised the study of all people identified as having common mental health problems (CMHP), those referred to the IAPT service, and a sample of attenders studied in-depth. Information technology makes it feasible to link practice, hospital and IAPT clinic data to evaluate the representativeness of these samples. However, researchers do not have permission to browse and link these data without the patients' consent.
OBJECTIVE: To demonstrate the use of a mixed deterministic-probabilistic method of secure and private record linkage (SAPREL)--to describe selection bias in subjects chosen for in-depth evaluation.
METHOD: We extracted, pseudonymised and used fuzzy logic to link multiple health records without the researcher knowing the patient's identity. The method can be characterised as a three party protocol mainly using deterministic algorithms with dynamic linking strategies; though incorporating some elements of probabilistic linkage. Within the data providers' safe haven we extracted: Demographic data, hospital utilisation and IAPT clinic data; converted post code to index of multiple deprivation (IMD); and identified people with CMHP. We contrasted the age, gender, ethnicity and IMD for the in-depth evaluation sample with people referred to IAPT, use hospital services, and the population as a whole.
RESULTS: The in IAPT-in-depth group had a mean age of 43.1 years; CI: 41.0-45.2 (n=166); the IAPT-referred 40.2 years; CI: 39.4-40.9 (n=1118); and those with CMHP 43.6 years SEM 0.15. (n=12210). Whilst around 67% of those with a CMHP were women, compared to 70% of those referred to IAPT, and 75% of those subject to in-depth evaluation (Chi square p<0.001). The mean IMD score for the in-depth evaluation group was 36.6; CI: 34.2-38.9; (n=166); of those referred to IAPT 38.7; CI: 37.9-39.6; (n=1117); and of people with CMHP 37.6; CI 37.3-37.9; (n=12143).
CONCLUSIONS: The sample studied in-depth were older, more likely female, and less deprived than people with CMHP, and fewer had recorded ethnic minority status. Anonymous linkage using SAPREL provides insight into the representativeness of a study population and possible adjustment for selection bias
Natalia LL - artystka neoawangardowa
No full textThe paper shows Natalia Lach-Lachowicz (Natalia LL) as a neo avant-garde artist whose works in a specific maximalistic way are very close to the main currents of avant-garde trends: new mediality (photography), minimalism, conceptualism, performance, bodyart, pop-art, and feminist art. The author of the article concentrates mainly on the mutual influences of conceptualism, consumptionism, and feminism in Natalia LL’s works and pays attention to the emancipatory potential of her works of the seventies and the eighties
[[alternative]]The Copper(II) Complexes of Glycine and L-Alanine
No full text[[abstract]]本研究合成兩系列二價銅錯合物,(1)[Cu(A)(L)](ClO4), A為甘胺酸(
gly)及丙胺酸(L-ala), L為乙二胺(en), 1,10-二氮雜菲(phen), 2,2'-聯
啶(bipy)及2,9-二甲基-1,10-二氮雜菲(neoc);(2)[Cu(pa)(L)](ClO4),pa
為 啶甲基丙胺酸(N-picolyl-(L)-alanine), L為N-甲基咪 (NMIm),
4-甲基咪 (4MIm), 4-甲基 啶(4Mpy)及 啶(py). 利用元素分析, 紅外
光光譜, 紫外光-可見光吸收光譜, 電子順磁共振光譜, CD光譜及x-光結
構解析等方法, 完成錯合物結構的鑑定及鍵結性質的研究.
Copper(II) complexes of two types, Cu(A)(LL)(ClO4) and Cu(
pa)(L)(ClO4), where A = glycine(gly) and L-alanine(L-ala); pa =
N-picolyl-(L)-alanine; LL = 1,10-phenanthroline(phen),
2,2'-bipyridine(bipy), neocuproine(neoc) and ethylenediamine(
en); L = N-methylimidazole(NMIm), 4-methylimidazole(4MImH),
4-methylpyridine(4Mpy) and pyridine(py), have been synthesized
andcharacterized by elemental analyses, IR, UV-VIS, CD and EPR
spectroscopicmeasurements.
Copper(II) complexes of two types, Cu(A)(LL)(ClO4) and Cu(
Energy flux in isotropic turbulence under large variations of external forcing
No full textWe investigate the response of energy flux in isotropic turbulence to step-function like perturbation in external forcing at large length scales. From both physical experiments and direct numerical simulations, we measured the evolution of the Eulerian velocity structure functions, such as , , before and after the perturbation in forcing. In both cases, we observed the cascade of the energy excess at large scales cascade through scales to the dissipative range, which can be used to study the dynamics of the cascade, and in particular, to estimate the relevant time scales
[[alternative]]Stereochemistry, Spectroscopic and Bonding Properties of 2,2-
No full text[[abstract]]本研究係以 2,2'-聯咪唑為主要研究的配子, 共合成四個系列二價銅
錯合物：
(1) [Cu(dien)(LL)]X2系列, 其中 dien 為二乙基三胺, LL 有乙二胺
(en), 1,10-二氮雜菲(phen), 2,2'-聯毗啶(bpy), 2,2'-聯咪唑(bimH2), X
為 ClO4-或 CF3SO3-.
(2) Cu(LL)2X2系列, 其中 LL有乙二胺 (en), 1,10-二氮雜菲(phen),
2,2'-聯毗啶(bpy), 2,2'-聯咪唑 (bimH2), X為 ClO4-或 CF3SO3-.
(3) Cu(bimH2)( LL)(ClO4)2系列, 其中 LL 有乙二胺(en), 1,10-二氮
雜菲(phen), 2,2'-聯毗啶(bpy), 和N,N'- 二甲基乙二胺(dmen).
(4) Cu(ImH)4X2 系列, X 有 CF3SO3-, NO3-, ClO4-, SO42- 和
Cu(bimH2)(L)2(ClO4)2 系列, L 有咪唑(ImH), 4-甲基咪唑(4MImH),
N-甲基咪唑(NMIm).
利用元素分析及紅外光譜來確定錯合物的合成. 紫外-可見光光譜,
電子順磁共振光譜和 X -光單晶繞射結構解析等方法, 研究各個錯
合物分子構造, 軌域能層分佈及鍵結性質. 每一系列均有一個供參
考比較的 X -光單晶繞射結構解析, 其資料如下：
(1) [Cu(dien)(bimH2)](ClO4)2, 單斜晶系, 空間群 P21/c, 晶格常數 a
= 11.001(2) , b = 12.412(3) , c = 14.456(2) , β = 94.28(1). 晶
胞值為 4 , 精算值 R = 0.071, Rw = 0.085.
(2) [Cu(bimH2)(bpy)(ClO4)](ClO4).H2O, 三斜晶系, 空間群 P1, 晶格
常數 a = 7.206(4) , b = 12.269(2) , c = 12.682(3) , α = 106.68(2)
, β = 96.91(3), γ = 93.94(3). 晶胞值為 2 , 精算值 R = 0.051, Rw
= 0.057.
(3) [Cu(bpy)2(CF3SO3)2], 三斜晶系, 空間群 P1, 晶格常數 a =
8.595(1) , b = 8.591(1) , c = 18.830(5) , α = 95.84(2), β =
95.87(2), γ = 108.65(1). 晶胞值為 2 , 精算值 R = 0.036, Rw =
0.043.
(4) [Cu(HIm)4(CF3SO3)2], 三斜晶系, 空間群 P21/n, 晶格常數 a =
9.116(4) , b = 9.559(1) , c = 14.664(5) , β = 106.19(3). 晶胞值
為 2 個分子, 精算值 R = 0.041, Rw = 0.052.
將每系列錯合物的紫外-可見光光譜均作高斯交疊解析, 可觀測本
研究主配子 2,2'-聯咪唑 (bimH2) 在錯合物的立體空間位置及影響
鍵結軌域之變化情況, 並培養出
[Cu(bimH2)(bpy)(ClO4)](ClO4).(H2O) 和 Cu(bpy)2(CF3SO3)2 薄片
單晶, 測其偏極光光譜及作高斯交疊解析, 發現配子的 π 電子和銅
原子的 d 軌域有不同程度的交互作用. d 軌域能層則依分子內原子
對稱性, 及空間位置而有分裂或升降現象, 主配子在錯合物的立體
空間位置明顯地和配子的π參與性能有關. 比較各系列銅混合配
子錯合物發現主配子在五配位的 CuN5 系統中具有 π 接受 性質
(π-accepting property); 在四配位的 CuN4 系統, 混合配子銅錯合物
為 Cu(bimH2)(L)2(ClO4)2 ,主配子 2,2'- 聯咪唑的 π 電子則有 π
供給性質 (π-donating property) .
Four kinds of mixed ligand biimidazole copper(II) complexes have been
prepared. These are :
(1) [Cu(dien)(LL)]X2 type, where dien stands for diethylenetriamine
(dien), and LL for ethylenediamine (en), 1,10-phenanthroline (phen),
2,2'-bipyridine (bpy), 2,2'-biimidazole (bimH2) and X for ClO4- or
CF3SO3-.
(2) Cu(LL)2X2 type, where LL stands for ethylenediamine (en), 1,10-
phenanthroline (phen), 2,2'-bipyridine (bpy), 2,2'-biimidazole (bimH2)
and X for ClO4- or CF3SO3-.
(3) Cu(bimH2)(LL)(ClO4)2 type, where LL stands for1,10-
phenanthroline (phen), 2,2'-bipyridine (bpy), N,N-
dimethylenethylenediamine (dmen) and ethylenediamine (en).
(4) Cu(ImH)4X2 and Cu(bimH2)(L)2(ClO4)2 type, where X is
CF3SO3-, NO3-, ClO4- and SO42- and L includes imidazole (ImH), 4-
methylimidazole (4MImH) and N-methylimidazole (NMIm).
The mixed ligand biimidazole copper(II) complexes have been
characterized by elemental analyses, and electronic, vibrational, and
spectroscopic measurements. X-ray crystal structures of the following
complexes have been determined from three-dimensional X-ray
diffraction data.
(1) [Cu(dien)(bimH2)](ClO4)2, monoclinic, space group P21/c, a =
11.001(2) , b = 12.412(3) , c = 14.456(2) , β = 94.28(1). z = 4,
R = 0.071, Rw = 0.085.
(2) [Cu(bimH2)(bpy)(ClO4)](ClO4).H2O, triclinic, space group P1, a
= 7.206(4) , b = 12.269(2) , c = 12.682(3) , α = 106.68(2), β =
96.91(3), γ = 93.94(3). z = 2, R = 0.051, Rw = 0.057.
(3) [Cu(bpy)2(CF3SO3)2], triclinic, space group P1, a = 8.595(1) , b
= 8.591(1) , c = 18.830(5) , α = 95.84(2), β = 95.87(2), γ =
108.65(1). . z = 2, R = 0.051, Rw = 0.057.. z = 2, R = 0.036, Rw =
0.043.
(4) [Cu(ImH)4(CF3SO3)2], monoclinic, space group P21/n, a =
9.116(4) , b = 9.559(1) , c = 14.664(5) , β = 106.19(3). z = 2,
R = 0.041, Rw = 0.052.
The sequence of the d orbitals has been deduced from Gaussian analysis
of the LF spectra. Single crystal polarized spectra for
[Cu(bimH2)(bpy)(ClO4)](ClO4)(H2O) and Cu(bpy)2(CF3SO3)2 have
been performed and analyzed. Bonding properties of biimidazole in
copper(II) complexes are elucidated and vary considerablly depending
on the structures of the complexes. In [Cu(dien)(bimH2)](ClO4)2
square bipyramidal system, biimidazole ligand is perpendicular to the
CuN4 basal plane showing strong π-accepting character. In
Cu(bimH2)2(ClO4)2 elongated Ohl system, biimidazole ligand is
bonded in the basal plane, and no π involved. In the
Cu(bimH2)(L)2(ClO4)2 system, biimidazole ligand is bonded in the
basal plane exhibits π donating properties.
Four kinds of mixed ligand biimidazole copper(II) complexes have been
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Some rhetorical strategies in later nineteenth-century laboring-class poetry
No full textStructural and functional analysis of the pro-domain of human cathelicidin, LL-37
No full textCathelicidins form a family of small host defense peptides distinct from another class of cationic antimicrobial peptides, the defensins. They are expressed as large precursor molecules with a highly conserved pro-domain known as the cathelin-like domain (CLD). CLDs have high degrees of sequence homology to cathelin, a protein isolated from pig leukocytes and belonging to the cystatin family of cysteine protease inhibitors. In this report, we describe for the first time the X-ray crystal structure of the human CLD (hCLD) of the sole human cathelicidin, LL-37. The structure of hCLD, determined at 1.93 Å resolution, shows the cystatin-like fold and is highly similar to the structure of the CLD of the pig cathelicidin, protegrin-3. We assayed the in vitro antibacterial activities of hCLD, LL-37 and the precursor form, pro-cathelicidin (also known as hCAP18), and we found that the unprocessed protein inhibited the growth of Gramnegative bacteria with efficiencies comparable to the mature peptide, LL-37. In addition, the antibacterial activity of LL-37 was not inhibited by hCLD intermolecularly, since exogenously added hCLD had no effect on the bactericidal activity of the mature peptide. hCLD itself lacked antimicrobial function and did not inhibit the cysteine protease, cathepsin L. Our results contrast with previous reports of hCLD activity. A comparative structural analysis between hCLD and the cysteine protease inhibitor stefin A showed why hCLD is unable to function as an inhibitor of cysteine proteases. In this respect, the cystatin scaffold represents an ancestral structural platform from which proteins evolved divergently, with some losing inhibitory functions
Flexible cross layer design for improved quality of service in MANETs
No full textThis thesis was submitted for the degree of Doctor of Philosophy and was awarded by Brunel UniversityMobile Ad hoc Networks (MANETs) are becoming increasingly important because of their unique characteristics of connectivity. Several delay sensitive applications are starting to appear in these kinds of networks. Therefore, an issue in concern is to guarantee Quality of Service (QoS) in such constantly changing communication environment. The classical QoS aware solutions that have been used till now in the wired and infrastructure wireless networks are unable to achieve the necessary performance in the MANETs. The specialized protocols designed for multihop ad hoc networks offer basic connectivity with limited delay awareness and the mobility factor in the MANETs makes them even more unsuitable for use. Several protocols and solutions have been emerging in almost every layer in the protocol stack.
The majority of the research efforts agree on the fact that in such dynamic environment in order to optimize the performance of the protocols, there is the need for additional information about the status of the network to be available. Hence, many cross layer design approaches appeared in the scene. Cross layer design has major advantages and the necessity to utilize such a design is definite. However, cross layer design conceals risks like architecture instability and design inflexibility. The aggressive use of cross layer design results in excessive increase of the cost of deployment and complicates both maintenance and upgrade of the network. The use of autonomous protocols like bio-inspired mechanisms and algorithms that are resilient on cross layer information unavailability, are able to reduce the dependence on cross layer design. In addition, properties like the prediction of the dynamic conditions and the adaptation to them are quite important characteristics.
The design of a routing decision algorithm based on Bayesian Inference for the prediction of the path quality is proposed here. The accurate prediction capabilities and the efficient use of the plethora of cross layer information are presented.
Furthermore, an adaptive mechanism based on the Genetic Algorithm (GA) is used to control the flow of the data in the transport layer. The aforementioned flow control mechanism inherits GA’s optimization capabilities without the need of knowing any details about the network conditions, thus, reducing the cross layer information dependence. Finally, is illustrated how Bayesian Inference can be used to suggest configuration parameter values to the other protocols in different layers in order to improve their performance.National Foundation of Scholarships of Greece(I.K.Y.
The effect of the Human Antimicrobial Peptide LL-37 and Dermcidin on bacterial growth
No full textWith multi resistant bacteria becoming an increasing clinical problem, research for alternative antibiotics is ever more important. One alternative molecule class to antibiotics could be antimicrobial peptides (AMPs), such as LL-37 that is secreted from the human epithelial cells. AMPs mainly kill bacteria by disrupting their membrane and can be described by three mechanistic models: the barrel stave, toroidal, and carpet model. In order to understand the potential for LL-37 as alternative to antibiotics, a bacteria growth experiment was performed, as well as cross-linking, to understand the interaction of LTA and LPS with LL-37. There was not a clear correlation between concentration of the two peptides, LL-37 and dermcidin, and the level of inhibition of the bacterial growth. No inhibition was observed in the experiment, and the minimal inhibitory concentration of LL-37 and dermcidin must therefore be above 6.4 μM for both E. coli and B. subtilis. Furthermore, LL-37 is found in various oligomeric conformation when cross-linked in the presence of LPS and LTA and its oligomeric state appears to be clearly affected by these molecules
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