Technological Change and Contribution to Growth and Convergence

Edward Nissan,Farhang Niroomand 중앙대학교 경제연구소 2006 Journal of Economic Development Vol.31 No.1

This paper incorporates data on efficiency and output per worker for 1965 and 1990 for 57 countries divided into four groups to seek an understanding of similarities and differences among them. Tools employed were testing for equality of means and testing for convergence. The findings indicate that the gaps between the groups were widened during the period studied for both efficiency and output per worker. While divergence was observed when all countries were grouped in one set, there were indications of convergence when the groups were treated separately.

Age as a Risk Factor for Intraoperative Periprosthetic Femoral Fractures in Cementless Hip Hemiarthroplasty for Femoral Neck Fractures: A Retrospective Analysis

Itay Ashkenazi,Nissan Amzallag,Shai Factor,Mohamed Abadi,Samuel Morgan,Aviram Gold,Nimrod Snir,Yaniv Warschawski 대한정형외과학회 2024 Clinics in Orthopedic Surgery Vol.16 No.1

Background: Understanding the risk factors and outcomes of intraoperative periprosthetic femoral fractures (IPFF) during hip arthroplasty is crucial for appropriate perioperative management. Previous studies have identified risk factors for IPFF in total hip arthroplasty patients, but data for hip hemiarthroplasty (HA) is lacking. The aim of this study was to determine the age associated with increased rates of IPFF in patients undergoing HA. Methods: We retrospectively reviewed patients aged 65 years and above who underwent a cementless HA for a displaced femoral neck fracture and had a minimum of 1-year follow-up. Patients were stratified into five age groups (65–79, 80–84, 85–89, 90–94, and ≥ 95 years) and further divided into two subgroups (under 95 years and 95 years or older). The presence, location, and treatment of IPFF, as well as the effect of IPFF on the postoperative weight-bearing status, were compared between groups. A multivariate logistic regression was also performed. A total of 1,669 met the inclusion criteria and were included in the study. Results: The rates of IPFF were significantly higher for patients 95 years or older (p = 0.030). However, fracture location (greater trochanter fractures, p = 0.839; calcar fractures, p = 0.394; and femoral shaft fractures p = 0.110), intraoperative treatment (p = 0.424), and postoperative weight-bearing status (p = 0.229) were similar between the groups. While mortality and nonorthopedicrelated readmissions were significantly higher for patients 95 years or older, orthopedic-related readmissions (p = 0.148) and revisions at the latest follow-up (p = 0.253) were comparable between groups. In a regression analysis, age over 95 years (odds ratio, 2.049; p = 0.049) and body mass index (odds ratio, 0.935; p = 0.016) were independently associated with IPFF. Conclusions: The findings of this study suggest that age over 95 years is a significant, independent risk factor for IPFF in patients undergoing cementless HA. Although we were unable to show an impact on perioperative outcomes and orthopedic complications, when operating on patients 95 years or older, surgeons should be aware of the increased risk of IPFF and consider the use of stem designs and fixation types associated with decreased IPFF rates.

Bioinspired materials for regenerative medicine: going beyond the human archetypes

Green, D. W.,Ben-Nissan, B.,Yoon, Kyung-Sik,Milthorpe, B.,Jung, H.-S. The Royal Society of Chemistry 2016 Journal of materials chemistry. B, Materials for b Vol.4 No.14

<P>The evolution of life has given rise to innumerable biomaterials with high levels of functional sophistication and performance among many thousands of different environments. The inexhaustible range of strategies and the intrinsic good design they possess can be readily included in the design of biomedical devices and materials, such as wound healing bandages and antibacterial surface coating implants. We highlight topical examples where various ingenious design strategies from biological models, originating more broadly from zoology and botany, have been appropriated into novel synthetic materials and structures for regenerative and material-based tissue engineering. Bioinspired materials engineering informed and enriched by the vast array of adaptations and strategies in nature, beyond human biology, will be instrumental in the future evolution of new more clinically acceptable pan-functional materials and structures with a broad range of uses in the regenerative sciences.</P>

Natural and Synthetic Coral Biomineralization for Human Bone Revitalization

Green, David W.,Ben-Nissan, Besim,Yoon, Kyung Sik,Milthorpe, Bruce,Jung, Han-Sung Elsevier 2017 Trends in biotechnology Vol.35 No.1

<P>Coral skeletons can regenerate replacement human bone in nonload-bearing excavated skeletal locations. A combination of multiscale, interconnected pores and channels and highly bioactive surface chemistry has established corals as an important alternative to using healthy host bone replacements. Here, we highlight how coral skeletal systems are being remolded into new calcified structures or synthetic corals by biomimetic processes, as places for the organized permeation of bone tissue cells and blood vessels. Progressive technologies in coral aquaculture and self-organization inorganic chemistry are helping to modify natural corals and create synthetic coral architectures able to accelerate bone regeneration with proper host integration at more skeletal locations, adapted to recent surgical techniques and used to treat intrinsic skeletal deformities and metabolic conditions.</P> <P><B>Trends</B></P> <P>Coral organisms secrete a range of zoological-wide bioactive proteins and molecules that permeate the skeleton. Some of these are potentially useful in biomedicine, including limited applications in reconstructive skeletal surgery.</P> <P>Coral polyp organisms can be nurtured within bioreactors on small microchips. These chips can promote the excretion of various human-active proteins and other biomolecules.</P> <P>Certain coralline structures have shown effectiveness as safe and effective drug carriers that deliver their payload on site with graduated dosages; others can be used as bioreactor environments for stem cell expansion and rapid specialization into bone tissues in laboratory cultivation and in patients.</P> <P>Techniques in biomimetic self-organization chemistry are providing the opportunity to grow synthetic coral-like structures and morphologies bearing component structures on many scales.</P>

Novel Brominated Quinoline and Pyrimidoquinoline Derivatives as Potential Cytotoxic Agents with Synergistic Effects of γ-Radiation

Mostafa M. Ghorab,Fatma A. Ragab,Helmi I. Heiba,Yassin M Nissan,Walid M. Ghorab 대한약학회 2012 Archives of Pharmacal Research Vol.35 No.8

New quinoline derivatives 6, 7 and 19, pyrimidoquinoline derivatives 8-16 and triazolopyrimidoquinoline derivatives 17 and 18 bearing a bromo-substituent were synthesized starting from 3-(4-Bromophenylamino)-5,5-dimethylcyclohex-2-enone 3. All the newly synthesized compounds were evaluated for their in vitro anticancer activity against human breast cancer cell line (MCF7). Compounds 9, 11, 17 and 18 showed IC50 values (36.4, 39.7, 39.02 and 36.4 μM, respectively) comparable to that of the reference drug doxorubicin (IC50 = 32.02 μM). On the other hand, compound 6, 14 and 19 exhibited better activity than doxorubicin with IC50 values of 8.5, 23.5 and 23.7 μM. Additionally, the most potent compounds 6, 14 and 19 were evaluated for their ability to enhance the cell killing effect of γ-radiation.

Effects of phase additions on three dimensionally ordered macroporous structure of SiO2-CaO-P2O5 bioactive glasses

Thanida Charoensuk,Chitnarong Sirisathitkul,Upsorn Boonyang,Innocent J. Macha,Yaowarat Sirisathitkul,Besim Ben-Nissan 한양대학교 세라믹연구소 2016 Journal of Ceramic Processing Research Vol.17 No.7

The three-phase of SiO2-CaO-P2O5 bioactive glass was successfully fabricated with three dimensionally ordered macroporous(3DOM) structure by incorporating a colloidal crystal template in the sol-gel synthesis. Whereas the composition andpurification of all four- and five-phase bioactive glasses were obtained after the inclusion of sodium nitrate and ferric nitratenonahydrate, the phase additions resulted in the deformation of the scaffolds and the curved walls were thinner with largervariations in size. Such difference was due to the gel-coating on spherical crystals instead of the filling in the interstitial holesof the template. Moreover, the bioactive glass microspheres were formed on the surface of the scaffolds due to the strongprecursor-template interactions. Nevertheless, the five-phase bioactive glasses exhibited the thermal stability up to 1000 oCwith slight mass loss and heat transfer.

Novel 4-(4-substituted-thiazol-2-ylamino)-N-(pyridin-2-yl)-benzenesulfonamides as Cytotoxic and Radiosensitizing Agents

Mostafa M. Ghorab,Fatma A. Ragab,Helmy I. Heiba,Hebaallah M. Agha,Yassin M. Nissan 대한약학회 2012 Archives of Pharmacal Research Vol.35 No.1

A series of novel 4-(4-substituted-thiazol-2-ylamino)-N-(pyridin-2-yl) benzene-sulfonamides were synthesized and screened for their cytotoxic activity against human breast cancer cell line (MCF-7). Compounds 6, 7, 9, 10, 11, and 14 displayed significant activity against MCF-7 when compared to doxorubicin, which was used as a reference drug. The synergistic effect of Gamma radiation for the most active derivatives 7, 9, and 11 was also studied and their IC50 values markedly decreased to 11.9 μM, 11.7 μM, and 11.6 μM, respectively.