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1.
Isis ; 106(3): 598-620, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26685519

ABSTRACT

The history of the theory of general relativity presents unique features. After its discovery, the theory was immediately confirmed and rapidly changed established notions of space and time. The further implications of general relativity, however, remained largely unexplored until the mid 1950s, when it came into focus as a physical theory and gradually returned to the mainstream of physics. This essay presents a historiographical framework for assessing the history of general relativity by taking into account in an integrated narrative intellectual developments, epistemological problems, and technological advances; the characteristics of post-World War II and Cold War science; and newly emerging institutional settings. It argues that such a framework can help us understand this renaissance of general relativity as a result of two main factors: the recognition of the untapped potential of general relativity and an explicit effort at community building, which allowed this formerly disparate and dispersed field to benefit from the postwar changes in the scientific landscape.


Subject(s)
Historiography , Physics/history , History, 20th Century , History, 21st Century
2.
Biotechnol Bioeng ; 67(3): 312-8, 2000 Feb 05.
Article in English | MEDLINE | ID: mdl-10620261

ABSTRACT

To perform their myriad functions, tissues use specific cell-cell interactions that depend on the spatial ordering of multiple cell types. Recapitulating this spatial order in vitro will facilitate our understanding of function and failure in native and engineered tissue. One approach to achieving such high placement precision is to use optical forces to deposit cells directly. Toward this end, recent work with optical forces has shown that a wide range of particulate materials can be guided and deposited on surfaces to form arbitrary spatial patterns. Here we report that, when we use the light from a near-infrared diode laser focused through a low numerical aperture lens, individual embryonic chick spinal cord cells can be guided through culture medium and deposited on a glass surface to form small clusters of cells. In addition, we found that the laser light could be coupled into hollow optical fibers and that the cells could be guided inside the fibers over millimeter distances. The demonstration of fiber-based guidance extends by 2 orders of magnitude the distance over which optical manipulation can be performed with living cells. Cells guided into the fiber remained viable, as evidenced by normal cell adhesion and neurite outgrowth after exposure to the laser light. The results indicate that this particle deposition process, which we call "laser-guided direct writing," can be used to construct patterned arrays of tens to hundreds of cells using arbitrary numbers of cell types placed at arbitrary positions with micrometer-scale precision.


Subject(s)
Biotechnology/instrumentation , Lasers , Micromanipulation/instrumentation , Spinal Cord/cytology , Animals , Biotechnology/methods , Cell Survival , Chick Embryo , Culture Techniques/instrumentation , Culture Techniques/methods , Fiber Optic Technology , Micromanipulation/methods , Optical Fibers , Silicon Dioxide
3.
Anticancer Res ; 20(5C): 3767-73, 2000.
Article in English | MEDLINE | ID: mdl-11268452

ABSTRACT

The nephrotoxic effects of different platinum compounds based combination chemotherapies were compared. Chemotherapy consisted of either cisplatin fractionated over 5 days (5 x 20 mg/m2) or given as a single-day infusion (1 x 50 mg/m2) plus ifosfamide (4 g/m2) or high-dose chemotherapy was applied including carboplatin (3 x 500 mg/m2) and ifosfamide (3 x 4 g/m2) fractionated over three consecutive days. Conventional parameters such as serum creatinine and glomerular filtration rate (GFR), as well as urinary protein excretion of N-acetyl-beta-D-glucosaminidase (NAG)) and alpha 1-micro-globulin were assessed in 52 patients. Fractionation over 5 days without adding other nephrotoxic agents, i.e. ifosfamide, prevented decreases in GFR following cisplatin, whereas the combination of conventional dose cisplatin and ifosfamide, given as a single-day infusion, and high-dose carboplatin/ifosfamide yielded a pronounced fall of GFR. All groups showed increases in the urinary excretion levels of serum derived proteins and NAG, but with significant differences; about 2 to 3-fold for 5-days cisplatin, 3 to 5-fold for single-day cisplatin/ifosfamide, and 20 to 35-fold for high-dose chemotherapy. Thus, conventional approaches can reduce but not prevent the nephrotoxicity of cisplatin-based chemotherapy. In particular, high-dose chemotherapy regimens including carboplatin and ifosfamide are associated with comparable or even higher nephrotoxicity to single-day cisplatin/ifosfamide. In the light of the long-term consequences of persistent renal damage prevention of nephrotoxicity should be further improved.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/adverse effects , Cisplatin/adverse effects , Ifosfamide/adverse effects , Kidney/drug effects , Neoplasms/drug therapy , Acetylglucosaminidase/urine , Adult , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/adverse effects , Breast Neoplasms/drug therapy , Cisplatin/administration & dosage , Creatinine/blood , Dose-Response Relationship, Drug , Female , Glomerular Filtration Rate/drug effects , Humans , Ifosfamide/administration & dosage , Kidney/pathology , Kidney Function Tests , Lymphoma, Non-Hodgkin/drug therapy , Magnesium/blood , Male , Middle Aged , Proteinuria , Testicular Neoplasms/drug therapy
4.
Trends Biotechnol ; 17(10): 385-9, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10481169

ABSTRACT

Laser-induced optical forces can be used to guide and deposit 100 nm - 10 microm-diameter particles onto solid surfaces in a process we call 'laser-guided direct writing'. Nearly any particulate material, including both biological and electronic materials, can be manipulated and deposited on surfaces with micrometer accuracy. Potential applications include three-dimensional cell patterning for tissue engineering, hybrid biological-electronic-device construction, and biochip-array fabrication.


Subject(s)
Biotechnology/methods , Lasers , Artificial Organs , Electronics , Optics and Photonics
6.
Phys Rev A ; 54(2): 1430-1434, 1996 Aug.
Article in English | MEDLINE | ID: mdl-9913608
9.
11.
Nurs Times ; 83(6): 19-20, 1987.
Article in English | MEDLINE | ID: mdl-3645599
12.
Nurs Times ; 82(5): 22-4, 1986.
Article in English | MEDLINE | ID: mdl-3633549
13.
Nurs Times ; 82(5): 26-7, 1986.
Article in English | MEDLINE | ID: mdl-3633551
14.
Nurs Times ; 80(46): 18-9, 1984.
Article in English | MEDLINE | ID: mdl-6568629
15.
Nurs Times ; 80(10): 19-20, 1984.
Article in English | MEDLINE | ID: mdl-6561530
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