Length of Dialysis Session Is More Important Than Large Kt/V in Hemodialysis

Long, slow hemodialysis (3 × 8 hours/week) has been used without significant modification in Tassin, France, for 30 years with excellent morbidity and mortality rates. A long dialysis session easily provides high Kt/V_urea and allows for good control of nutrition and correction of anemia with a limited need for erythropoietin (EPO). Control of serum phosphate and potassium is usually achieved with low-dose medication. The good survival achieved by long hemodialysis sessions is essentially due to lower cardiovascular morbidity and mortality than in short dialysis sessions. This, in turn, is mainly explained by good blood pressure (BP) control without the need for antihypertensive medication. Normotension in this setting is due to the gentle but powerful ultrafiltration provided by the long sessions, associated with a low salt diet and moderate interdialytic weight gains. These allow for adequate control of extracellular volume (dry weight) in most patients without important intradialytic morbidity. Therefore, increasing the length of the dialysis session seems to be the best way of achieving satisfactory long-term clinical results.     

Direct bonding with on-wafer metal interconnections

A low temperature direct bonding process with encapsulated metal interconnections was proposed. The process can be realized between silicon wafers or silicon and glass wafers. To establish well-insulated electric connection, sputtered aluminum film was patterned between a bottom thermal SiO₂ and a top PE-SiO₂; the consequential uneven wafer surface was planarized through a chemical mechanical polishing (CMP) step. Benefit from this smooth surface finish, direct bonding is achieved at room temperature, and a general yielding rate of more than 95% is obtained. Test results confirmed the reliability of the bonding. The main advantages of this new technology are its electric connectivity, low thermal stress and hermeticity. This process can be utilized for the packaging of micro electro mechanical system (MEMS) devices or the production of SOI wafers with pre-fabricated electrodes and wires.     

Influence of the additives argon, O2, C4F8, H2, N2 and CO on plasma conditions and process results during the etch of SiCOH in CF4 plasma

Reactive ion etch processes for modern interlevel dielectrics become more and more complex, especially for further scaling of interconnect dimensions. The materials will be damaged within such processes with the result of an increase in their dielectric constants. The capability of selected additives to minimize the low-k sidewall damage during reactive ion etching (RIE) of SiCOH materials in fluorocarbon plasmas was shown in different works in the past. Most of the investigated additive gases alter the fluorine to carbon ratio as well as the dissociation of the parent gas inside the etch plasma. The result is a changed etch rate, a modified polymerization behavior and other characteristics of the process induced SiCOH damage. Heavy inert ions like argon will be accelerated to the sample surface in the cathode dark space and enhance therewith the sputter yield on the SiCOH network [1]. In this paper the additives Ar, O₂, C₄F₈, H₂, N₂ and CO were added to a conventional CF₄ etch plasma. We try to provoke different changes in the plasma conditions and therewith in the process results. Contact angle measurements, spectroscopic ellipsometry, Hg-probe analysis, FTIR measurements and SEM cross-sections were used to overview the additive induced modifications. To understand the influences of the additives gases more exactly, changes in the physical and chemical plasma behavior must be analyzed. Therefore quadrupole mass spectrometry (QMS) and quantum cascade laser absorption spectroscopy (QCLAS) were used.     

基于ZigBee无线通信的汽车倾斜度测量的应用

引言ZigBee是一种新的无线局域网传输标准,它是基于IEEE802.15.4协议基础的一个通信标准。IEEE802.15.4定义了协议的物理层和媒体介质访问控制层(MAC),而ZigBee定义了网络层、安全层和应用层,见图1。这样,     

The nanometre-scale physiology of bone: steric modelling and scanning transmission electron microscopy of collagen�Cmineral structure

The nanometre-scale structure of collagen and bioapatite within bone establishes bone''s physical properties, including strength and toughness. However, the nanostructural organization within bone is not well known and is debated. Widely accepted models hypothesize that apatite mineral (‘bioapatite’) is present predominantly inside collagen fibrils: in ‘gap channels’ between abutting collagen molecules, and in ‘intermolecular spaces’ between adjacent collagen molecules. However, recent studies report evidence of substantial extrafibrillar bioapatite, challenging this hypothesis. We studied the nanostructure of bioapatite and collagen in mouse bones by scanning transmission electron microscopy (STEM) using electron energy loss spectroscopy and high-angle annular dark-field imaging. Additionally, we developed a steric model to estimate the packing density of bioapatite within gap channels. Our steric model and STEM results constrain the fraction of total bioapatite in bone that is distributed within fibrils at less than or equal to 0.42 inside gap channels and less than or equal to 0.28 inside intermolecular overlap regions. Therefore, a significant fraction of bone''s bioapatite (greater than or equal to 0.3) must be external to the fibrils. Furthermore, we observe extrafibrillar bioapatite between non-mineralized collagen fibrils, suggesting that initial bioapatite nucleation and growth are not confined to the gap channels as hypothesized in some models. These results have important implications for the mechanics of partially mineralized and developing tissues.     

CdS-sensitized TiO2 in phenazopyridine photo-degradation: Catalyst efficiency,stability and feasibility assessment

Mineralization of phenazopyridine, 1, in water, under solar-simulator radiation was efficiently achieved using nanoparticle CdS-sensitized rutile TiO₂, TiO₂/CdS, 2, as photo-catalysts. Despite that, 2 showed two main drawbacks. Firstly, the system was difficult to recover by simple filtration, and demanded centrifugation. Secondly, the sensitizer CdS showed relatively high tendency to leach out hazardous Cd²⁺ ions under photo-degradation reaction conditions. In an attempt to solve out such difficulties, 2 was supported onto sand surface. The sand/TiO₂/CdS system, 3, was easier to recover but showed slightly lower catalytic activity compared to 2. On the other hand, the support failed to prevent leaching of Cd²⁺. This indicates limited future applicability of CdS-sensitized TiO₂ photo-catalyst systems, in solar-based water purification strategies, unless leaching out tendency is completely prevented.     

Do ‘green’ buildings have better indoor environments? New evidence

A post-occupancy evaluation (POE) of 12 green and 12 conventional office buildings across Canada and the northern United States was conducted. Occupants (N = 2545) completed an online questionnaire related to environmental satisfaction, job satisfaction and organizational commitment, health and well-being, environmental attitudes, and commuting. In each building on-site physical measurements at a sample of workstations (N= 974) were taken, including: thermal conditions, air quality, acoustics, lighting, workstation size, ceiling height, window access and shading, and surface finishes. Green buildings exhibited superior performance compared with similar conventional buildings. Better outcomes included: environmental satisfaction, satisfaction with thermal conditions, satisfaction with the view to the outside, aesthetic appearance, less disturbance from heating, ventilation and air-conditioning (HVAC) noise, workplace image, night-time sleep quality, mood, physical symptoms, and reduced number of airborne particulates. A variety of physical features led to improved occupant outcomes across all buildings, including: conditions associated with speech privacy, lower background noise levels, higher light levels, greater access to windows, conditions associated with thermal comfort, and fewer airborne particulates. Green building rating systems might benefit from further attention in several areas, including: credits related to acoustic performance, a greater focus on reducing airborne particulates, enhanced support for the interdisciplinary design process and development of POE protocols.

Il a été mené une évaluation après occupation (POE) de 12 immeubles de bureaux verts et 12 immeubles de bureaux classiques répartis à travers le Canada et le nord des Etats-Unis. Les occupants (N?=?2545) ont rempli un questionnaire en ligne portant sur la satisfaction environnementale, la satisfaction au travail et l'implication organisationnelle, la santé et le bien-être, les attitudes environnementales, et les trajets réguliers. Dans chaque immeuble, des mesures physiques in situ sur un échantillon de postes de travail (N?=?974) ont été effectuées, comprenant : les conditions thermiques, la qualité de l'air, l'acoustique, l'éclairage, la taille des postes de travail, la hauteur de plafond, l'accès aux fenêtres et leur occultation, et les finitions de surface. Les bâtiments verts ont affiché des performances supérieures par rapport aux bâtiments classiques similaires. De meilleurs résultats ont été obtenus concernant la satisfaction environnementale, la satisfaction à l'égard des conditions thermiques, la satisfaction à l'égard de la vue sur l'extérieur, l'aspect esthétique, la diminution des perturbations liées aux bruits provenant du chauffage, de la ventilation et de la climatisation (CVC), l'image du lieu de travail, la qualité du sommeil nocturne, l'humeur, les symptômes physiques, et la réduction du nombre de particules en suspension dans l'air. Différentes caractéristiques physiques ont conduit à une amélioration des résultats pour les occupants dans tous les immeubles, concernant notamment les conditions liées à la confidentialité des conversations, les niveaux inférieurs de bruit de fond, les niveaux de luminosité plus élevés, l'accès accru aux fenêtres, les conditions associées au confort thermique, et le nombre moindre de particules en suspension dans l'air. Les systèmes de notation des bâtiments verts pourraient bénéficier d'une plus grande attention apportée à plusieurs domaines, s'agissant en particulier des crédits relatifs aux performances acoustiques, d'un accent accru sur la réduction des particules en suspension dans l'air, d'un soutien renforcé en faveur du processus de conception interdisciplinaire et du développement de protocoles POE.

Mots clés: performances des bâtiments, bilan environnemental, bâtiments verts, environnement intérieur, Leadership in Energy and Environmental Design (LEED), satisfaction des occupants, évaluation après occupation     

中小城市——法国国土开发的催化剂

法国有大量的中小城市,这些城市在1945—1973年间经历了急剧的人口和经济增长。从那以后,中小城市的活力与大聚落的活力就不相上下。半个多世纪以来,小城市发展的重要因素是欧洲的农业政策,中型城市则受益于法国的国土规划政策。然而无论中型城市还是小城市又各自有其内生的发展,主要因为它们提供的良好生活环境可以促进住宅经济发展。法国北方分布较多工业,只要它们懂得创新之道就能抵抗风险;南方以旅游业为主,是全球旅游的胜地。总之,中小城市以它们特有的吸引力为国土的发展做出了贡献。