Shear velocity-based uncertainty quantification for rock joint shear strength

Bulletin of Engineering Geology and the Environment - The shear strength of rock joints is an important property required in order to analyze the stability of rock slopes and tunnels. However,...     

Excipients in parenteral formulations: selection considerations and effective utilization with small molecules and biologics

Excipients form a major component of pharmaceutical formulations and are classified as any ingredient other than the active ingredient which is included within the product formulation to improve drug product performance. Functional uses of excipients include improving solubility and stability, safety and efficacy, as bulking agents in lyophilized formulations, tonicity agents, and aiding in controlled or prolonged drug delivery. Parenteral formulations are sterile, pyrogen-free; free of particulate matter and by-pass the body’s natural defense mechanisms. Excipients may demonstrate a synergistic effect when combined with an active ingredient but may also lead to unwanted reactions with the drugs and packaging components. Ideal excipients are required to be considered safe, inert and multifunctional. Contrary to the past, safety of excipients needs to be well established in order for their use in the pharmaceutical formulations. Therefore, careful consideration should be given while selecting an excipient. This review article provides an overview of the excipients used exclusively in small molecule and biological parenteral products including solutions, suspensions, and lyophilized formulations, information on the possible drug-excipient and drug-packaging interactions and the regulatory requirements for the use of pharmaceutical excipients. The readers will be able to have a comprehensive understanding of the excipients used in parenteral formulations.     

Thermal comfort in apartments in India: Adaptive use of environmental controls and hindrances

Energy used in buildings in India is ever-increasing. About 47% of total energy in Indian residential buildings is used for ventilation controls alone. Comfort temperatures defined in Indian codes are inappropriate (23–26 °C). There are no thermal comfort field studies in residences reported from India. The author conducted a field study in apartments in Hyderabad, in summer and monsoon seasons in 2008. The present paper discusses the occupants’ methods of environmental control, behavioural adaptation and impediments.Due to poor adaptive opportunities, about 60% of occupants were uncomfortable in summer. The comfort range obtained in this study (26.0–32.5 °C), was way above the standard. Fanger’s PMV always overestimated the actual sensation.The occupants adapted through the use of personal environmental controls, clothing, metabolism and many behavioural control actions. Use of fans, air coolers and A/c s increased with temperature, and was impeded by their poor efficacy and noise, occupant’s attitudes and economic affordability. Air-coolers and A/c s were mostly used in top- floors, as the available adaptive opportunities were insufficient. Behavioural adaptation was higher in summer and was limited in higher economic groups always. Subjects frequently exposed to A/c environments, tolerated thermal extremes little, and desired “thermal indulgence”. This study calls for special adaptation methods for top-floor flats.     

The three-dimensional model of Dictyostelium discoideum racE based on the human rhoA-GDP crystal structure

The three-dimensional structure of racE was modeled using several homologous small G proteins, and the best model obtained using the human rhoA as modeling template is reported. The three-dimensional fold of the racE model is remarkably similar to the cellular form of human ras p21 crystal structure. Its secondary structure consists of six alpha-helices, six beta-strands and three 3(10) helices. The model retains its secondary structure after a 300 K, 300 ps molecular dynamics (MD) simulation. Important domains of the protein include its effector loop (residues 34-46), the insertion domain (residues 121-136), and the polybasic motif (between 210 and 220) not modeled in the current structure. The effector loop is inherently flexible and the structure docked with GDP exhibits the effector loop moving significantly closer to the nucleotide binding pocket, forming a tighter complex with the bound GDP. The mobility of the effector loop is conferred by a single residue 'hinge' point at residue 34Asp, also allowing the Switch I region, immediately preceding the effector loop, to be equally mobile. In comparison, the Switch II region shows average mobility. The insertion domain is highly flexible, with the insertion taking the form of a helical domain, with several charged residues forming a complex charged interface over the entire insertion region. While the GDP moiety is loosely held in the active site, the metal cation is extensively co-ordinated. The critical residue 38Thr exhibits high mobility, and is seen interacting directly with the metal ion at a distance of 2.64 A, and indirectly via an intervening water molecule. 64Gln, a key residue involved in GTP hydrolysis in ras, is seen facing the beta-phosphate group and the metal ion. Certain residues (i.e. 51Asn, 38Thr and 65Glu) exhibit unique characteristics and these residues, together with 158Val, may play important roles in the maintenance of the protein's integrity and function. There is strong consensus of secondary structural elements between models generated using various templates, such as h-rac1, h-rhoA and h-cdc42 bound to RhoGDI, all sharing only 50-55% sequence identity with racE, which suggests that this model is in all probability an accurate prediction of the true tertiary structure of racE.     

Laser-induced breakdown spectroscopy for the environmental determination of total carbon and nitrogen in soils

Soils from various sites have been analysed with the laser-induced breakdown spectroscopy (LIBS) technique for total elemental determination of carbon and nitrogen. Results from LIBS have been correlated to a standard laboratory-based technique (sample combustion), and strong linear correlations were obtained for determination of carbon concentrations. The LIBES technique was used on soils before and after acid washing, and the technique appears to be useful for the determination of both organic and inorganic soil carbon. The LIBS technique has the potential to be packaged into a field-deployable instrument.     

Dynamic Power-Conscious Routing for MANETs: An Initial Approach

We develop an initial dynamic power-concious routing scheme (MPR) that incorporates physical layer and link layer statistics to conserve power, while compensating for the channel conditions and interference environment at the intended receiver. The aim of MPR is to route a packet on a path that will require the least amount of total power expended and for each node to transmit with just enough power to ensure reliable communication. We evaluate the performance of MPR and present our preliminary results.     

Mixing studies of non-Newtonian fluids in an anchor agitated vessel

The success of any mixing operation involving liquid–liquid, gas–liquid and gas–liquid–solid systems depends mainly on the geometry of the vessel and impeller, operating conditions and properties of the system. Transformation of laboratory results to commercial scale unit is very difficult due to the complexity of flow phenomena and the scale up is being done by adopting a conservative approach which is based on the geometric, kinematic and dynamic similarities. This approach does not take into account the non-ideal flow behavior of the fluid and the design of commercial unit will be more rational if this information is included in the design of the unit.     

BALINIT(R)--我们的目标是提高您的生产力

巴尔查斯公司是世界一流的涂层供应商,作为UNAXIS集团中最具活力的一员,拥有世界领先的镀膜和真空技术.巴尔查斯长期致力于开发各种涂层及涂层工艺、销售系统以及生产设备,并且是唯一一家通过其目前设在欧洲、美洲和亚洲拥有70多个涂层中心的全球网络向世界各地的客户提供涂层服务的公司.巴尔查斯拥有世界领先的涂层设备,作为工具和精密元件耐磨涂层的供应者已经有27年之久.巴尔查斯的真空涂层系统广泛应用在提高各种工具和精密元件的性能上,效果十分显著.在金属切削、冲压成型和塑料模具等应用方面,巴尔查斯涂层在极大提高硬度的同时,能显著减少摩擦,提高生产能力,从而降低生产成本.实践证明,在使用巴尔查斯涂层后,汽车发动机、传动设备和水压系统精密部件的使用寿命被显著延长.