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In this article, the seismic performance of box-shaped steel piers embedded with energy-dissipating shells under a multi-directional seismic load is investigated. A finite element (FE) model was accurately established and verified by the quasi-static test results. A parametric analysis of the hysteretic behaviour of a novel box-shaped steel pier under eccentric pressure was carried out on this basis. We discussed the influence of the eccentricity, axial compression ratio, thickness of embedded shell, ratio of slenderness, spacing of transverse stiffening ribs on the embedded shell, and width-to-thickness ratio of wallboard on the anti-seismic performance of a novel box-shaped steel bridge pier. The results revealed that the load carrying capacity and ductility coefficient of the specimen are substantially influenced by the eccentricity, variation in the axial compression ratio, and slenderness ratio. The specimen’s plastic energy dissipation capacity can be effectively improved by increasing the thickness of the embedded shell. The spacing of the transverse stiffening ribs only marginally affects seismic performance. In addition, the width-to-thickness ratio of the wallboard exerts a more considerable influence on the deformability of the square-section specimen. Finally, a formula for calculating the bearing capacity of the novel box-shaped steel piers under cyclic loading is proposed.

Crosstalk-free reconstruction of multiple images within a single element can greatly boost the image capacity and information security. We herein demonstrate a viable approach by integrating upconversion and holographic images into a single holographic polymer nanocomposite. The holographic image is reconstructed through photopolymerization-induced phase separation under a 460 nm laser and identifiable under room light, while the upconversion image recognizable under a 980 nm laser is photopatterned via spatially photobleaching of the dye embedded in the upconversion nanoparticle (UCNP) shell under 365 nm light. To this end, the lanthanide-doped UCNP in the core/shell/shell nanostructure of NaYF4:20%Yb3+,0.5%Tm3+@NaYF4@SiO2 is designed, and the dye, fluorescein isothiocyanate (FITC), is fixed in the outermost SiO2 shell via the amine-isothiocyanate reaction and the subsequent sol-gel reaction. Energy transfer from the core of the UCNP to FITC embedded in the shell is critical to boosting the contrast of the upconversion image, which dials the emission color from blue to yellow-green. It is also found that the upconversion image can be brightened by increasing the UCNP content while the holographic image is weakened when the UCNP content is over 15 wt %. This study paves a new way toward advanced anticounterfeiting.

With the increasing demand for multidimensional data processing, Geometric algebra (GA) has attracted more and more attention in the field of geographical information systems. GA unifies and generalizes real numbers and complex, quaternion, and vector algebra, and converts complicated relations and operations into intuitive algebra independent of coordinate systems. It also provides a solution for solving multidimensional information processing with a high correlation among the dimensions and avoids the loss of information. Traditional methods of computer vision and artificial intelligence (AI) provide robust results in multidimensional processing after being combined with GA and give additional feature analysis facility to remote sensing images. In this paper, we provide a detailed review of GA in different fields of AI and computer vision regarding its applications and the current developments in geospatial research. We also discuss the Clifford-Fourier transform (CFT) and quaternions (sub-algebra of GA) because of their necessity in remote sensing image processing. We focus on how GA helps AI and solves classification problems, as well as improving these methods using geometric algebra processing. Finally, we discuss the issues, challenges, and future perspectives of GA with regards to possible research directions.

Background Imerslund-Gräsbeck Syndrome (IGS) is mainly caused by CUBN gene biallelic mutations. Proteinuria accompanies IGS specific symptoms in about half of the patients, isolated proteinuria is rarely reported. Here we present 3 patients with isolated proteinuria and focal segmental glomerulosclerosis (FSGS) caused by CUBN gene biallelic pathogenic variants. Method Whole exome sequencing was performed on three children with isolated proteinuria. CUBN gene biallelic pathogenic variants were found and then verified by sanger sequencing. Their clinical, pathological and molecular genetic characteristics were analyzed and correlated accordingly. Results All three children presented with isolated proteinuria, no megaloblastic anemia. Their urine levels of β2 microglobulin were normal or slightly higher. Renal biopsies showed focal segmental glomerulosclerosis with mild glomerular mesangial hypercellularity, partial effacement of foot processes and podocyte microvillation. Two of them were found to carry compound heterozygous mutations and one homozygous mutation of CUBN gene. Totally four CUBN gene biallelic pathogenic variants were identified, including c.9287 T > C (p.L3096P), c.122 + 1G > A, c.7906C > T (p.R2636*), c.10233G > A (p.W3411*). Except for intron splice-site mutation, all other variants are located in highly conserved sites of CUB domain for binding to albumin. Conclusion The results demonstrate that CUBN gene mutations may cause isolated proteinuria pathologically presented as FSGS. Our cases extend the spectrum of renal manifestation and genotype of CUBN gene mutations.

Background Everolimus permits reduced calcineurin inhibitor (CNI) exposure, but the efficacy and safety outcomes of this treatment after kidney transplant require confirmation.Methods In a multicenter noninferiority trial, we randomized 2037 de novo kidney transplant recipients to receive, in combination with induction therapy and corticosteroids, everolimus with reduced-exposure CNI (everolimus arm) or mycophenolic acid (MPA) with standard-exposure CNI (MPA arm). The primary end point was treated biopsy-proven acute rejection or eGFR Results In the intent-to-treat population (everolimus n=1022, MPA n=1015), the primary end point incidence was 48.2% (493) with everolimus and 45.1% (457) with MPA (difference 3.2%; 95% confidence interval, -1.3% to 7.6%). Similar between-treatment differences in incidence were observed in the subgroups of patients who received tacrolimus or cyclosporine. Treated biopsy-proven acute rejection, graft loss, or death at post-transplant month 12 occurred in 14.9% and 12.5% of patients treated with everolimus and MPA, respectively (difference 2.3%; 95% confidence interval, -1.7% to 6.4%). De novo donor-specific antibody incidence at 12 months and antibody-mediated rejection rate did not differ between arms. Cytomegalovirus (3.6% versus 13.3%) and BK virus infections (4.3% versus 8.0%) were less frequent in the everolimus arm than in the MPA arm. Overall, 23.0% and 11.9% of patients treated with everolimus and MPA, respectively, discontinued the study drug because of adverse events.Conclusions In kidney transplant recipients at mild-to-moderate immunologic risk, everolimus was non-inferior to MPA for a binary composite end point assessing immunosuppressive efficacy and preservation of graft function.

A closed-cycle system by storing and releasing solar energy without additional interchange of material is crucial for future high global energy demands. Here, we presented a solid-state molecular solar thermal fuels (STFs) composed of single-walled carbon nanotubes and azobenzene with push-pull electron structure (AZO-SWCNTs) employing the direct Friedel-crafts acylation reaction. This kind of STFs reveals the highest gravimetric energy density of 80.7 Wh kg−1 and power density of 292 W kg−1 in AZO-CNTs STFs system with extended half-lifetime and excellent photochemical cycling stability. Moreover, the high performance and closed cycle of storage and heat release of the solid-state STFs assembly film were also investigated. The STFs shows relatively a high energy storage efficiency (12.4%) and a solar energy storage efficiency (0.25%) with a maximum temperature difference of 10 °C. This kind of solid-state STFs film exhibits a great potency in high-energy and short-term solar energy thermal storage.

SnO2-Al2O3 (SAO) binary thin films were prepared on slide glasses substrates by RF magnetron sputtering. The influence of the substrate temperature on the surface morphology, crystal structures, electrical and optical properties were analyzed by the scanning electron microscopy (SEM) images, X-ray diffraction (XRD) patterns, four-probe measuring, UV-IR and photoluminescence (PL) spectra. With increasing substrate temperature, the grain sizes of SAO binary films are increased. Uniform patterns and large size grains indicate a better surface morphology and crystallinity of SAO films, which are verified by SEM and XRD investigations. All the films have a high average transmittivity of ∼80%∼90% in visible light region 400∼800 nm. The calculated band gap is in a range of ∼4.11∼4.14 eV, and the measured sheet resistances of SAO films are in a range of ∼7.0×104 to ∼9.4×104 Ω/□. At proper sputtering temperature, the band gap can be widened, and the sheet resistances can be reduced. The PL emissions from the films in UV and red bands were also observed. These polycrystalline SAO films can be used in the application of transparent conductive oxide (TCO) films, solar cell windows, sensors, as well as lighter emitters.

Derived from RNA, 5'-ribonucleotides, especially Inosine-5'-monophosphate (IMP) and guanosine-5'-monophosphate (GMP), can enhance the umami taste of soy sauce. In this study, the RNA content of three different salt-tolerant yeasts was examined. The most valuable strain was subjected to atmospheric and room-temperature plasma (ARTP) mutagenesis, which improved its RNA content by 160.54%. Regular fermentation with RNA-enhanced strain failed to increase the amount of 5'-ribonucleotides in the soy sauce due to hydrolysis by phosphatase. A two-stage fermentation strategy was then carried out. Aroma compounds were mainly synthesized in the first stage, and RNA-enriched biomass was massively produced in the second stage followed by heat treatment to inactivate phosphatase. After the proposed strategy was applied, IMP and GMP in the soy sauce reached 68.54 and 89.37 mg/L, respectively. Moreover, the amounts of key aroma compounds and organic acids significantly increased. Results may provide new insights for improving the quality of soy sauce through microorganism breeding and fermentation control.

Due to the drill pipe in the Riserless Mud Recovery (RMR) system is exposed to seawater, so the characteristics of the temperature changing are very different from the conventional offshore drilling. Considering temperature is an important factor affecting the annulus pressure, it is necessary to study the variation law of the temperature field of the RMR. In this paper, according to the physical process of the heat transfer in RMR, the mathematical model of the temperature field is established. The Computational Fluid Dynamics (CFD) software is used to simulate the temperature distribution in the drill pipe and the annulus, so that the law of the temperature changing can be observed more intuitively. In order to be more aware of the influencing factors of the temperature field changing, this paper analyzes the influence mechanism of the different discharge capacity and the different injection temperature on temperature changing. Moreover, this paper also analyzes the influence of the annulus temperature on the annulus pressure, which provides a theoretical basis for the well control of RMR.

Holographic polymer nanocomposites with upconversion photoluminescence functions have drawn extensive attention. Yet, it still remains challenging to boost the upconversion emission intensity while maintaining a high diffraction efficiency. Herein, we demonstrate a viable approach to fabricating holographic polymer nanocomposites with both high diffraction efficiency and bright upconversion emission by enriching the core-shell structured upconversion nanoparticles (UCNPs) into the constructive regions while enriching the liquid crystal into the destructive regions during photopolymerization. It is found that the mass ratio of oleic acid to H2O (e.g., 2.41–7.65) on the surface of UCNPs plays a critical role to achieve the attractive holographic polymer nanocomposites. Colored holographic images identifiable to the public under room light with four encrypted upconversion emission states (e.g., none, blue, yellow-green and red) are achieved. Moreover, the holographic images are able to show distinct colors at different viewing angles and can be switched by electric fields, showing unclonable features for advanced anti-counterfeiting applications.

Around View Monitoring (AVM) system is a computer vision application in advanced driver-assistance systems (ADASs). When using full high-definition (HD) camera, it brings significant challenge to system design. Multi-channel HD cameras bring great pressure to video processing system, especially the communication between the processing circuit and memory. To address these issues, this paper proposes a software-hardware co- designed AVM system. In particular, we present and implement a computational efficient composing algorithm for high quality bird's-eye view image and a cost efficient hardware architecture for low memory bandwidth. The performance of the proposed full HD AVM system can reach up to 30 frames per second.

Background: Osteoporotic vertebral compression fracture (OVCF) is the most common complication of osteoporosis, however, debate persists over which procedure of percutaneous vertebroplasty (PVP) or balloon kyphoplasty (BKP) is a better treatment. We performed a metaanalysis of prospective, randomized controlled and clinical controlled trials of PVP and BKP to determine the efficacy and safety for the treatment of OVCFs to reach a relatively conclusive answer. Materials and Methods: We searched computerized databases comparing efficacy and safety of PVP and BKP in osteoporotic vertebral compression fractures. These reports included pain relief, functional capacity (Oswestry disability index [ODI] score), anterior vertebral body height (AVBH), kyphotic angle and complications (i.e. cement leakage, incident fractures). Studies were assessed for methodological bias and potential reasons for heterogeneity were explored. Results: As of March 15, 2013, a PubMed search resulted in 761 articles, of which eleven studies encompassing 789 patients, met the inclusion criteria. The average length of followup is 17 months and 4.6% patients were lost to followup. Results of metaanalysis indicated that BKP is more effective for short term pain relief. In addition, BKP is more effective to restore the AVBH (anterior vertebral body height), ODI and kyphotic angle of OVCFs. Moreover, BKP need more polymethylmethacrylate amount. Conclusions: In terms of better effectiveness of BKP procedure, we believe BKP to be superior over PVP for the treatment of osteoporotic VCFs.

A simulation system of single-pass microwave photon filter to generate the ultra-wideband (UWB) signal and transmit the base band signal by unexploited band is proposed. The simultaneous transmission of base band wired signal and UWB wireless signal in wavelength-division multiplexing passive optical network (WDM-PON) is realized. Which would reduce cost greatly while improving significantly the spectrum efficiency of a WDM-PON system. Eye diagrams and electrical spectra measurements show that the interference between the two signals is very small.

This paper presents a new design of a dual-band Frequency Selective Surface based on using different kinds of FSS units nested together, and the impact of its performance for the change of unit size, medium thickness, incidence angle and other factors are summarized in detail. At last, a dual-band FSS operating at 5/19.5GHz respectively is designed, and it has a stable resonant frequency in TE and TM mode.

The strip-line TEM cell is used to measure the EMC of equipment and devices. Strip-line TEM cell can be widely used in measuring the EMC (Electromagnetic Compatibility) performance from automotive industry to IC components. In this paper we present three different strip-line TEM cells. And cut slot on conductor can extend the frequency range of strip-line TEM cell. The cost is lower, the operation is easier, and the cell is more applicability with this method.

Optical Time Division Multiplexing (OTDM) is one of the effective methods to improve the transmission rate of optical communications [1]. Optical communications researchers use optical method to convert electric time division-multiplexing signal into higher rate optical signal. OTDM system overcomes the limited rate of electronic communication [7]. In this paper, we simulate and design a point to point 40Gbps OTDM system by using OptiSystem, and use DPSK (Differential Phase-Shift Keying) modulation format in this system. It achieves efficient and reliable transmission of data which satisfies an ever-growing demand for bandwidth of high-speed optical fiber communications.

A novel Virtual Measurement System (VMS) of ARINC429 bus signal electrical parameter is designed to improve test accuracy and maintenance efficiency of avionics devices. This software of the VMS is implemented based on Labwindows/CVI. The hardware of the VMS is constructed by using data acquisition card to test voltage parameters and by using microcontroller and voltage comparators to test time parameters. A communication radio panel is used to check ARINC 429 bus signal electrical parameters by using the VMS and the oscilloscope Rigol DS5102M. The Mean Square Error (MSE) of voltage parameters measured by the VMS is 0.002V, and that measured by the oscilloscope is 0.155V. And the MSE of time parameters measured by the VMS is 0.06tμs, and that measured by the oscilloscope is 0.09μs. The results show that the VMS has higher test accuracy in voltage and time parameter measurement than those of the oscilloscope.

INTRODUCTION We investigated the effect of defibrase (a proteolytic enzyme extraction of Agkistrodon halys venom) on experimental autoimmune myositis (EAM) in guinea pigs and explored the option of using a modified pig model of EAM to enhance the study of this disease. MATERIAL AND METHODS Guinea pigs were divided into 3 groups: group A (control group) was immunized with complete Freund adjuvant (CFA), then received 6 injections of saline weekly; group B (EAM group) was immunized with partially purified rabbit myosin emulsified with CFA, then received an injection of saline; group C (EAM + defibrase group) was immunized with purified rabbit myosin emulsified with CFA, then received an injection of defibrase. The animals were observed for their general health condition and the body weight was measured daily. Plasma levels of fibrinogen and creatine kinase (CK) were determined. Muscle tissues were examined histologically. RESULTS After immunizations for 6 weeks, incidence of EAM in groups A, B and C was 0 (0/7), 83.3% (10/12) and 100% (15/15), respectively. Guinea pigs with EAM presented angeitis symptoms of muscle weakness. Histological analysis revealed a significant difference. Muscles with EAM had scattered or diffuse inflammatory manifestations, which are also common pathological features of human idiopathic polymyositis (IPM). Defibrase-treated animals displayed extensive inflammation and fiber necrosis compared with the EAM group (histological score: 2.80 ±1.15 vs. 1.88 ±1.32, p < 0.05). Severity of inflammation of group B was mainly mild to moderate; 16.7% (2/12) of animals developed severe inflammation. Incidence of severe inflammation with a score up to 4 in group C was 40% (6/15). CONCLUSIONS Defibrase can exacerbate myosin-induced EAM; thus a new modified model was generated.

Tricuspid dysfunction induced by pacemaker-lead perforation is rare. We now report a case of a patient with progressive right-sided heart failure due to severe tricuspid regurgitation due to perforation from a previously placed pacemaker lead.

Based on the theory of transmission and reflection of stress wave, several multi-layered structures with foam-concrete in civil engineering were proposed to decrease the strength of stress wave and hence, to raise the protective performance of underground structures. The propagation of stress wave in the multi-layered structures was simulated and the dynamic response and damage development of the structures were studied by commercial dynamic finite element software LS-DYNA. The results showed that multi-layered structures can reduce the strength of impacting loading and the range of spalling damage of the structures effectively.

Associative memory schemes have been developed for Evolutionary Algorithms (EAs) to solve Dynamic Optimization Problems (DOPs), and demonstrated powerful performance. In these schemes, how to update the memory could be important for their performance. However, little work has been done about the associative memory updating strategies. In this paper, a novel updating strategy is proposed for associative memory schemes. In this strategy, the memory point whose associated environmental information is most similar to the current environmental information is first picked out from the memory. Then, the selected memory individual is updated according to the fitness value, and the associated environmental information is updated according to the matching degree between environmental information and individuals. This updating strategy is embedded into a state-of-the-art algorithm, i.e. the MPBIL, and tested by experiments. Experimental results demonstrate that the proposed updating strategy is helpful for associative memory schemes to enhance their search ability in cyclic dynamic environments.

Based on Zhang’s short signature scheme without random oracles and k+1-square roots assumption, a new fair contract signing protocol with the off-line semi-Trusted Third Party is given because the disadvantages of existed fair contract signing protocol. The off-line semi-TTP intervenes into the protocol in cases where one party attempts to cheat or simply crashes to make the fair exchange optimistic. The off-line TTP need not be completely trusted, since the TTP can get neither exchanged signature when dispute is mediated. Because this protocol is based on short signature, which needs low storage and little communication, it can be used in low-bandwidth communication and low-storage environments.

In this paper, a resonance-free power quality controller (RFPQC) for middle voltage distribution system is described. The RFPQC system discussed in paper exhibits the following advantages: (a) The RFPQC has good filtering performance to eliminate most of the harmonic current generated by nonlinear load in characteristic frequency; (b) The RFPQC can damp parallel resonance between PF and grid impedance driving by load current; (c) The RFPQC also can damp series resonance between PF and grid impedance driving by grid voltage; (d) The harmonic current source in RFPQC has very small power rating comparing with nonlinear load. In this paper, the topology and control strategy has been analyzed in detail. The simulation and experiment result certify the RFPQC system has propose performance.

Using formal method is an effective methodology for modeling and verifying software system. Describing and verifying cryptographic protocol by formal method is an important research. Pi-calculus is a kind of mobile process algebra which can be used to model concurrent and dynamic system. Mobility workbench (MWB) is an automatic tool for pi-calculus and can be used for analyzing and verifying mobile concurrent system described by pi-calculus. In this paper we analyze Aziz-Diffie wireless communication security protocol using formal method based pi-calculus and verifying the attack of this protocol by MWB.

Intelligent information system, based on mathematically modeling, data processing and experimental research, can help reduce the operating cost owing to fast reaction and effective control, and help disadvantaged users understand all useful information, which result in more profits and less loss. Framework of information processing, definitions of the concepts, regression equations, and economic evaluation of Intelligent Information System were discussed. Factors, including users' ability to understand, improvement of mathematical models, evaluation of production cost, and adaptation to changing environment, affect the efficiency of the intelligent information system. The experimental results obtained during pilot-scale fermentation suggested that intelligent information system benefited the bioconversion of agricultural residues to reducing sugars.

Structurized video representation and indexing based on the representation are the foundation of video retrieval based on content. A novel algorithm is presented of automatically parsing and labelling video based on camera motion qualitative analysis. Firstly, the motion patterns are analyzed of the spatio-temporal slices in a video; and then the change detection and qualitative recognition of camera motion are carried out by using motion structure tensor. Finally, the results of camera motion analysis are used to parse and label video according to the camera motion coherence. The algorithm is experimentally proved effective and produces satisfactory results.

IP traceback is an important task in Internet security area. Techniques have been developed to deploy in pure IP network, but, to date, no system has been presented to use the facility of MPLS in MPLS-enabled network. We present Overlay Logging, a technique combines the hash based logging (SPIE) and the convenience of setup overlay network in MPLS network. Our system can achieve a relatively lower false positive rate than SPIE, needs less hardware investment, and reduces the storage pressure. It is impervious to multi-path routing in the network. What's more, the network overhead and configuration cost of our system is low.

Flip chip on board (FCOB) technology has been in widespread application. The reliability testing of solder-joints and the delamination between underfill and chip or substrate is still a critical issue for FCOB technology. In this paper, an accelerated environmental testing HAST-was used to rapidly evaluate the reliability of area array solder bumped packages on FR-4 PCBs. The test results intend to identify the effective reliability test criteria for low-cost FCOB technology.

We demonstrate a cost effective, linearly tunable fiber optical parametric oscillator based on a home-made photonic crystal fiber pumped with a mode-locked ytterbium-doped fiber laser, providing linely tuning ranges from 1018 nm to 1038 nm for the idler wavelength and from 1097 nm to 1117 nm for the signal wavelength by tuning the pump wavelength and the cavity length. In order to obtain the desired fiber with a zero dispersion wavelength around 1060 nm, eight samples of photonic crystal fibers with gradually changed structural parameters are fabricated for the reason that it is difficult to accurately customize the structural dimensions during fabrication. We verify the usability of the fabricated fiber experimentally via optical parametric generation and conclude a successful procedure of design, fabirication, and verification. A seed source of home-made all-normal-dispersion mode-locked ytterbium-doped fiber laser with 38.57 ps pulsewidth around the 1064 nm wavelength is used to pump the fiber optical parametric oscillator. The wide picosecond pulse pump laser enables a larger walk-off tolerance between the pump light and the oscillating light as well as a longer photonic crystal fiber of 20 m superior to the femtosecond pulse lasers, resulting in a larger parametric amplification and a lower threshold pump power of 15.8 dBm of the fiber optical parametric oscillator.

Three-dimensional mode coupling around a conical seamount in an ocean waveguide is studied. It is shown that strong mode coupling occurs at the edge of a conical seamount for the incident normal modes with significant amplitudes below the top of the seamount. Therefore, mode coupling is critical for the investigation of the acoustic field around a seamount. In addition, we suggest the use of random discretization for representing smoothly varying bathymetry. For the use of uniform discretization, when the horizontal step size is greater than half of the wavelength, artificial diffraction lobes appear due to coherent backscatter. However, by using the random discretization scheme instead, such artificial diffraction lobes are diffused, resulting in a faster convergence rate.

Observer design for non-linear systems is difficult work, especially for systems of high order. In this paper, we first present a state-space representation of a fluid pipeline. Then we turn the non-linear observer design task into optimization problems in order to bridge the gap between non-linear observer theory and its applications. In applying this method to the discrete high-order model of a pipeline, analytic solutions can easily be obtained. A structural condition for observers to be robust to pipeline friction and diameter variations is also proved through steady-state analysis. Simulation studies and experiments on a water pipeline show that: (a) the observers designed converge rapidly and reliably; (b) the computational expenditure is very small in comparison with the Kalman filter; and (c) friction and diameter variations may have little influence on the estimation accuracy.

In Distributed Parameter Systems (DPS), faults often appear as undesirable parametric variations in an unknown region of system space. In view of the difficulty of general identificata on of space-dependent parameters in nonlinear DPS and the distinctive features of fault diagnosis, a special fault identification technique is developed in this paper by the introduction of a Faulty Zone (FZ) concept. Fault diagnosis of DPS can thus be simplified as identification of three types of parameters: 1) the location of FZ; 2) the size of FZ and 3) the extent of parameter variations in FZ. This technique is applied successfully to the diagnosis of local diameter reduction of fluid transport pipeline by means of a hierarchic space division scheme and stochastic approximation algorithm. Simulation study and experimental results are included.

In order to investigate the response of breast cancer cells to anticancer drugs as a function of hormone receptors, 69 specimens obtained from the primary tumor of invasive breast cancer patients were cultivated using the human tumor clonogenic assay. Successful growth in vitro (≥ 30 colonies per plate) was obtained in 50 (72.5%) of the 69 viable samples, with a median cloning efficiency of 0.17%. Five drugs (adriamycin, vincristine, 5-fluorouracil, carmustine, methotrexate) were tested for each specimen resulting in 250 drug assays. The overall drug sensitivity was 47.2%. Of these, 5-fluorouracil had the greatest effect in vitro with a sensitivity of 68.0%. There was no significant correlation between hormone receptor status and response to anticancer drugs either overall or for agents analyzed individually. It is concluded that hormone receptors of breast cancer have no predictive value for response to chemotherapy.