RESUMEN
Solid-state drives (SSDs) that do not have internal dynamic random-access memory (DRAM) are being widely spread for client SSD and embedded SSD markets in recent years because they are cheap and consume less power. Obviously, their performance is lower than conventional SSDs because they cannot exploit advantages of DRAM in the controller. However, this problem can be alleviated by using host memory buffer (HMB) feature of Non-Volatile Memory Express (NVMe), which allows SSDs to utilize the DRAM of host. In this paper, we show that commercial DRAM-less SSDs clearly exhibit worse I/O performance than SSDs with internal DRAM, but this can be improved by using the HMB feature. We also present methods that reveal how the host memory buffer is used in commercial DRAM-less SSDs to improve I/O performance. Through extensive experiments, we conclude that DRAM-less SSDs evaluated in this study mainly exploit the host memory buffer as an address mapping table cache rather than a read cache or write buffer to improve I/O performance.
Asunto(s)
Periféricos de Computador/tendencias , Equipos de Almacenamiento de Computador/tendencias , Computadores/tendencias , Algoritmos , Periféricos de Computador/economía , Periféricos de Computador/estadística & datos numéricos , Equipos de Almacenamiento de Computador/estadística & datos numéricosRESUMEN
We contrasted performance with mouse and light pen input devices for younger, middle-aged, and older adults (N = 72) who were experienced mouse users. Participants used both preferred and nonpreferred hands to perform a menu target selection task. The light pen minimized age differences in performance relative to the mouse. Older adults were more lateralized on a handedness test than young adults and were less efficient using their nonpreferred hand. With practice, older adults improved their response time more than other age groups did. The mouse was rated as more acceptable and easier to use than the light pen across trials, despite the performance advantage of the light pen for all age groups. Usability ratings correlated moderately with performance. A benefit-cost analysis indicated that the more efficient light pen might cover its greater initial cost within 11 months for an older adult and within 23 months for a younger adult. Actual or potential applications of this research include advising older adults to persist with practice for new input devices, advising those who must switch to their non-preferred hand to select a direct positioning device, and providing a methodology for determining the potential payback interval when switching to a faster, though more expensive, input device.
Asunto(s)
Envejecimiento/fisiología , Periféricos de Computador/economía , Periféricos de Computador/tendencias , Desempeño Psicomotor/fisiología , Análisis y Desempeño de Tareas , Adulto , Factores de Edad , Anciano , Actitud hacia los Computadores , Estudios de Cohortes , Análisis Costo-Beneficio , Femenino , Mano/fisiología , Humanos , Luz , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Programas InformáticosRESUMEN
We present a new technique that uses a custom-built ink-jet printer to fabricate precise micropatterns of cell adhesion materials for neural cell culture. Other work in neural cell patterning has employed photolithography or "soft lithographic" techniques such as micro-stamping, but such approaches are limited by their use of an un-alterable master pattern such as a mask or stamp master and can be resource-intensive. In contrast, ink-jet printing, used in low-cost desktop printers, patterns material by depositing microscopic droplets under robotic control in a programmable and inexpensive manner. We report the use of ink-jet printing to fabricate neuron-adhesive patterns such as islands and other shapes using poly(ethylene) glycol as the cell-repulsive material and a collagen/poly-D-lysine (PDL) mixture as the cell-adhesive material. We show that dissociated rat hippocampal neurons and glia grown at low densities on such patterns retain strong pattern adherence for over 25 days. The patterned neurons are comparable to control, un-patterned cells in electrophysiological properties and in immunocytochemical measurements of synaptic density and inhibitory cell distributions. We suggest that an inexpensive desktop printer may be an accessible tool for making micro-island cultures and other basic patterns. We also suggest that ink-jet printing may be extended to a range of developmental neuroscience studies, given its ability to more easily layer materials, build substrate-bound gradients, construct out-of-plane structure, and deposit sources of diffusible factors.
Asunto(s)
Adhesión Celular/fisiología , Técnicas de Cultivo de Célula/métodos , Periféricos de Computador/normas , Impresión/instrumentación , Impresión/métodos , Animales , Agregación Celular/fisiología , Separación Celular/instrumentación , Separación Celular/métodos , Células Cultivadas , Colágeno , Periféricos de Computador/tendencias , Neuroglía/citología , Neuronas/citología , Neuronas/fisiología , Técnicas de Placa-Clamp , Polietilenglicoles , Polilisina , Ratas , Esferoides Celulares/citología , Esferoides Celulares/fisiología , Factores de TiempoAsunto(s)
Implantes Absorbibles/tendencias , Órganos Artificiales/tendencias , Ingeniería de Tejidos/instrumentación , Ingeniería de Tejidos/métodos , Trasplante de Tejidos/instrumentación , Trasplante de Tejidos/métodos , Agregación Celular/efectos de los fármacos , Células Cultivadas/trasplante , Periféricos de Computador/tendencias , Geles/farmacología , Geles/uso terapéutico , Humanos , Impresión/instrumentación , Impresión/métodos , Impresión/tendencias , Programas Informáticos/tendenciasRESUMEN
We have developed several devices for positioning organic molecules, molecular aggregates, cells, and single-cell organisms onto solid supports. These printers can create stable, functional protein arrays using an inexpensive technology. The cell printer allows us to create cell libraries as well as cellular assemblies that mimic their respective position in organs. The printers are derived from commercially available ink-jet printers that are modified to dispense protein or cell solutions instead of ink. We describe here the modifications to the print heads, and the printer hardware and software that enabled us to adapt the ink-jet printers for the manufacture of cell and protein arrays. The printers have the advantage of being fully automated and computer controlled, and allow for the high-throughput manufacture of protein and cell arrays.
Asunto(s)
Periféricos de Computador/tendencias , Impresión/instrumentación , Análisis por Matrices de Proteínas/instrumentación , Proteómica/instrumentación , Animales , Órganos Artificiales/tendencias , Bovinos , Técnicas de Cultivo de Célula/instrumentación , Técnicas de Cultivo de Célula/métodos , Células Cultivadas , Células Eucariotas/química , Técnicas de Cultivo de Órganos/instrumentación , Técnicas de Cultivo de Órganos/métodos , Impresión/métodos , Análisis por Matrices de Proteínas/métodos , Proteínas/análisis , Proteínas/química , Proteómica/métodos , Reproducibilidad de los Resultados , Ingeniería de Tejidos/instrumentación , Ingeniería de Tejidos/métodosRESUMEN
We recently developed a cell printer (Wilson and Boland, 2003) that enables us to place cells in positions that mimic their respective positions in organs. However, this technology was limited to the printing of two-dimensional (2D) tissue constructs. Here we describe the use of thermosensitive gels to generate sequential layers for cell printing. The ability to drop cells on previously printed successive layers provides a real opportunity for the realization of three-dimensional (3D) organ printing. Organ printing will allow us to print complex 3D organs with computer-controlled, exact placing of different cell types, by a process that can be completed in several minutes. To demonstrate the feasibility of this novel technology, we showed that cell aggregates can be placed in the sequential layers of 3D gels close enough for fusion to occur. We estimated the optimum minimal thickness of the gel that can be reproducibly generated by dropping the liquid at room temperature onto a heated substrate. Then we generated cell aggregates with the corresponding (to the minimal thickness of the gel) size to ensure a direct contact between printed cell aggregates during sequential printing cycles. Finally, we demonstrated that these closely-placed cell aggregates could fuse in two types of thermosensitive 3D gels. Taken together, these data strongly support the feasibility of the proposed novel organ-printing technology.
Asunto(s)
Órganos Artificiales/normas , Periféricos de Computador/tendencias , Geles , Técnicas de Cultivo de Órganos/instrumentación , Impresión/instrumentación , Animales , Bovinos , Agregación Celular/fisiología , Técnicas de Cultivo de Célula/instrumentación , Técnicas de Cultivo de Célula/métodos , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Células Cultivadas , Colágeno/farmacología , Geles/farmacología , Técnicas de Cultivo de Órganos/métodos , Impresión/métodos , Esferoides Celulares/citología , Esferoides Celulares/efectos de los fármacos , Esferoides Celulares/fisiología , Ingeniería de Tejidos/instrumentación , Ingeniería de Tejidos/métodosAsunto(s)
Computadoras de Mano , Radiología , Actitud hacia los Computadores , Periféricos de Computador/tendencias , Computadoras de Mano/tendencias , Difusión de Innovaciones , Humanos , Sistemas de Atención de Punto/tendencias , Interpretación de Imagen Radiográfica Asistida por Computador , Integración de SistemasAsunto(s)
Computadores/normas , Toma de Decisiones en la Organización , Sistemas de Información en Hospital/normas , Periféricos de Computador/normas , Periféricos de Computador/tendencias , Computadores/tendencias , Sistemas de Información en Hospital/tendencias , Sistemas de Registros Médicos Computarizados , Ohio , Programas Informáticos/normas , Programas Informáticos/tendencias , Estados Unidos , Interfaz Usuario-ComputadorAsunto(s)
Periféricos de Computador/tendencias , Sistemas de Atención de Punto/tendencias , Administración de la Práctica Médica/tendencias , Sistemas de Información en Farmacia Clínica , Difusión de Innovaciones , Prescripciones de Medicamentos , Humanos , Internet , Innovación Organizacional , Teléfono , Estados UnidosAsunto(s)
Periféricos de Computador/tendencias , Telecomunicaciones/tendencias , Periféricos de Computador/estadística & datos numéricos , Difusión de Innovaciones , Eficiencia Organizacional , Personal de Salud , Hospitales Públicos/organización & administración , Internet , Radio , Medicina Estatal/organización & administración , Reino UnidoAsunto(s)
Conservación de los Recursos Naturales/tendencias , Sistemas de Información Radiológica/tendencias , Periféricos de Computador/economía , Periféricos de Computador/tendencias , Conservación de los Recursos Naturales/economía , Análisis Costo-Beneficio , Sistemas de Información Radiológica/economía , Estados Unidos , Película para Rayos X/economía , Película para Rayos X/provisión & distribución , Película para Rayos X/tendenciasRESUMEN
Today's users face a dizzying array of interface tools from which to choose. Keyboard, mouse, voice or touchscreen, Windows, pull-down menus, point-and-click--so many choices, but which is best?