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1.
Chemometrics has enjoyed tremendous success in the areas related to calibration of spectrometers and spectroscopy-based measurements. These chemometric-based spectrometers have been widely applied for process monitoring and quality assurance. However, chemometrics has the potential to revolutionize the very intellectual roots of problem solving. Are there barriers to a more rapid proliferation of chemometric-based thinking, particularly in industry? What are the potential effects of chemometrics technology and the New Network Economy (NNE) working in concert? Who will be the winners in the race for faster, better, cheaper systems and products? These questions are reviewed in terms of the principles of the NNE and in the promise of chemometrics for industry. What then is the state of multivariate thinking in industry? Several powerful principles are derived from an evaluation of the NNE and chemometrics which could allow chemometrics to proliferate much more rapidly as a key general problem-solving tool.  相似文献   
2.
A patient who developed a mixed neuroendocrine carcinoma and adenocarcinoma at the site of a previous long-standing ileostomy is reported. The neuroendocrine features are documented by both ultrastructural and immunocytochemical findings. Carcinoma arising in an ileostomy site is rare but has been recorded in patients with long-standing ileostomies after colectomy for chronic inflammatory bowel disease, as in this patient. Neuroendocrine carcinoma developing in this setting apparently has not been described before, however.  相似文献   
3.
In microbiology laboratories highly infectious material is handled alongside complex and potentially dangerous equipment, and staff are therefore at risk of infections and accidents. Acts of parliament and regulations exist to protect staff in the workplace, including those exposed to biological agents. The current monitoring of health and safety in laboratories seeks to ensure that employers and employees comply with existing regulations, but this form of passive surveillance is of limited value because it does not highlight shortcomings in techniques, equipment, premises, or personnel. We propose a scheme for the surveillance of health and safety in microbiology laboratories that will actively seek information about laboratory incidents and practices, in order to enable appropriate preventive measures to be instituted.  相似文献   
4.
Demands by Patients or their Families for treatment thought to be inappropriate by health care providers constitute an important set of moral problems in clinical practice. A variety of approaches to such cases have been described in the literature, including medical futility, standard of care and negotiation. Medical futility fails because it confounds morally distinct cases: demand for an ineffective treatment and demand for an effective treatment that supports a controversial end (e.g., permanent unconsciousness). Medical futility is not necessary in the first case and is harmful in the second. Ineffective treatment falls outside the standard of care, and thus health care workers have no obligation to provide it. Demands for treatment that supports controversial ends are difficult cases best addressed through open communication, negotiation and the use of conflict-resolution techniques. Institutions should ensure that fair and unambiguous procedures for dealing with such cases are laid out in policy statements.  相似文献   
5.
Physical and temporal boundaries are rapidly diminishing in an age of swiftly advancing information communication technologies. Today’s technologically sophisticated business and organizational environments offer a number of distance collaboration modalities (DSMs) that can facilitate efficient and cost-effective meetings that have traditionally required face-to-face meeting venues. Selection of the DCMs that maximize meeting effectiveness is significantly challenging given the wide diversity of available options. Theory and empirical data can be useful as a guide in the selection of the most appropriate DCMs to maximize organizational productivity and success. This article reviews the literature on the behavioral and technical affordances and limitations of the various DCMs. It also provides a theoretical model based on media synchronicity theory to help guide selection of effective DCMs. This theoretical framework emphasizes the primacy of media alignment with core communication processes as well as social and interpersonal factors that influence meeting effectiveness.  相似文献   
6.
With the objective of clarifying the nature of renin-like activity in the brain, we have devised methods to distinguish true renin from acid protease. These methods were used to determine the regional distribution of true renin in hog brain. The pineal was found to be the richest source of renin followed by the adenohypophysis and choroid plexus. The hypothalamus, cerebellum and amygdala contained moderately high concentrations of renin. Renin concentration in the neurohypophysis was negligible. Many regions contained activatable prorenin. The molecular weight and the pH-dependence of the brain renin were identical to these same properties of renal and plasma renins. Based upon its specific affinity to concanavalin A, brain renin was judged to be a glycoprotein. The electrofocusing pattern of renin from different regions of the brain differed from that of plasma and kidney renins, a discrepancy which could be interpreted as evidence for the endogenous synthesis of renin in the brain.  相似文献   
7.
The valence-band electron (EVB) tunneling current in partially depleted silicon-on-insulator (SOI) MOSFETs increases as the gate oxide gets thinner and affects the dynamic behavior of devices and circuits. We present an engineering model of EVB tunneling current based on the surface-potential formulation. The new model is implemented in a SOI MOSFET compact model and is used to study the impact of EVB tunneling on circuit performance. Simulations of stacked logic gates show that the EVB tunneling current not only boosts circuit switching speed but also mitigates the history dependence of propagation delays  相似文献   
8.
ABSTRACT

Recently, research on information security has expanded from its purely technological orientation into striving to understand and explain the role of human behavior in security breaches. However, an area that has been lacking theory-grounded empirical study is in social engineering attacks. While there exists an extensive body of anecdotal literature, factors that account for attack success remains largely speculative. To better understand this increasing phenomenon, we developed a theoretical framework and conducted an empirical field study to investigate social engineering attacks, and from these results, we make recommendations for practice and further research.  相似文献   
9.
Magnesium (Mg) alloys are promising scaffolds for the next generation of cardiovascular stents because of their better biocompatibility and biodegradation compared to traditional metals. However, insufficient mechanical strength and high degradation rate are still the two main limitations for Mg materials. Hydrofluoric acid (HF) treatment and collagen coating were used in this research to improve the endothelialization of two rare earth-based Mg alloys. Results demonstrated that a nanoporous film structure of fluoride with thickness of ~20 μm was formed on the Mg material surface, which improved the corrosion resistance. Primary human coronary artery endothelial cells (HCAECs) had much better attachment, spreading, growth and proliferation (the process of endothelialization) on HF-treated Mg materials compared to bare- or collagen-coated ones.  相似文献   
10.
A hydrologic model was calibrated and evaluated for predicting water storage and transport in loose-dump mine spoil. Large columns were assembled in the laboratory to represent the four surface treatments of sieved spoil, topsoil + sieved spoil, topsoil only, and unamended spoil (control). A drainage outlet was placed at the bottom of each column and used to collect percolation through the columns. Rainfall was applied to the columns and simulated in the hydrologic model. Hydrologic parameters of saturated hydraulic conductivity, lambda, porosity and saturated water content were varied to calibrate the model to the observed data for all treatment groups. A separate rainfall sequence was used to evaluate the hydrologic response of the model. The calibrated parameters provided excellent predictions of water transport for all treatment groups. Water storage characteristics were increased by adding surface amendments to the control in all cases primarily because of the addition of microporosity to the system.  相似文献   
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