Complex optical index of single wall carbon nanotube films from the near-infrared to the terahertz spectral range

We retrieve the complex optical index of single-walled carbon nanotube (CNT) films in the 0.6-800 μm spectral range. Results are obtained from a complete set of optical measurements, reflection and transmission, of free-standing CNT films using time domain spectroscopy in the terahertz (THz) and Fourier transform infrared (IR) spectroscopy in the visible-IR. Based on a Drude-Lorentz model, our results reveal a global metallic behavior of the films in the IR, and confirm their high optical index in the THz range.     

Cadmium uptake by floating macrophytes.

Cd uptake capacity of a group of floating macrophytes (Salvinia herzogii, Pistia stratiotes, Hydromistia stolonifera and Eichhornia crassipes) was determined in outdoors experiments during the lowest temperature period of the year. Although all studied species were highly efficient in the Cd uptake, Pistia stratiotes was selected for further research because of its superior performance and its higher average relative growth rate. Cadmium% removal by Pistia stratiotes was greater in the first 24 h of the experiments (63, 65, 72 and 74% of the added Cd for 1, 2, 4 and 6 mg Cd 1(-1), respectively). After 31 days of growth, Pistia statiotes efficiently removed Cd at the studied concentrations. The macrophyte was able to keep its capacity for Cd removal even though some toxicity symptoms appeared at 4 and 6 mg Cd 1(-1). The greater the initial concentration, the greater Cd bioaccumulation rates. The increase of Cd concentration in plant tissues occurred especially in roots and was linearly related to the quantity of Cd added. Cd sorption by roots is faster than translocation to the plant aerial part and it occurs mainly during the first 24h.     

Design Optimization of a SiGe/Si Quantum-Well Optical Modulator

In this paper, design optimization of a SiGe/Si quantum-well optical modulator integrated on silicon-on-insulator (SOI) substrate to achieve high-frequency operation is reported. The structure, based on free-carrier depletion in a PIN diode, is integrated in a rib waveguide. Influence of geometrical parameters, layer doping, and metal contacts is determined through numerical simulations and optimized structures are defined. The obtained figure of merit V_piL_pi is 1.8 V-cm.     

Why perinatal mortality cannot be a proxy for maternal mortality

Although vasodilator agents have been used to alleviate the pain of complex regional pain syndromes, the precise mechanism of pain relief is not well known. In this study the effects of various kinds of vasodilators on primary afferent nociceptors were investigated by measuring the thermal pain threshold. Evaluated in the study were the effects of guanethidine (2 mg/mL), nicardipine (0.2 mg/mL). Nitroglycerin (0.3 mg/mL), and prostaglandin E1 (1 microgram/mL) on the cutaneous pain threshold and blood flow at 7-day intervals in six healthy volunteers. Each aliquot of 0.5 mL of the test vasodilator or lidocaine (10 mg/mL) and saline (control) were intradermally injected at three sites each on both forearms. The pricking-pain threshold and skin tissue blood flow were determined using a radiant heat-stimulating system and a laser-Doppler tissue-blood flowmeter, respectively. The pain threshold increased with lidocaine, guanethidine, and nicardipine; remained unchanged with Nitroglycerin; but decreased with prostaglandin E1. In contrast, the skin tissue blood flow increased by four to nine times with all vasodilators. These results indicate that the effect of vasodilators on primary afferent nociceptors is not related to the vasodilating effect and may not involve a common mechanism of action for pain relief in complex regional pain syndromes.     

Too far to walk: maternal mortality in context

The Prevention of Maternal Mortality Program is a collaborative effort of Columbia University's Center for Population and Family Health and multidisciplinary teams of researchers from Ghana, Nigeria and Sierra Leone. Program goals include dissemination of information to those concerned with preventing maternal deaths. This review, which presents findings from a broad body of research, is part of that activity. While there are numerous factors that contribute to maternal mortality, we focus on those that affect the interval between the onset of obstetric complication and its outcome. If prompt, adequate treatment is provided, the outcome will usually be satisfactory; therefore, the outcome is most adversely affected by delayed treatment. We examine research on the factors that: (1) delay the decision to seek care; (2) delay arrival at a health facility; and (3) delay the provision of adequate care. The literature clearly indicates that while distance and cost are major obstacles in the decision to seek care, the relationships are not simple. There is evidence that people often consider the quality of care more important than cost. These three factors--distance, cost and quality--alone do not give a full understanding of decision-making process. Their salience as obstacles is ultimately defined by illness-related factors, such as severity. Differential use of health services is also shaped by such variables as gender and socioeconomic status. Patients who make a timely decision to seek care can still experience delay, because the accessibility of health services is an acute problem in the developing world. In rural areas, a woman with an obstetric emergency may find the closest facility equipped only for basic treatments and education, and she may have no way to reach a regional center where resources exist. Finally, arriving at the facility may not lead to the immediate commencement of treatment. Shortages of qualified staff, essential drugs and supplies, coupled with administrative delays and clinical mismanagement, become documentable contributors to maternal deaths. Findings from the literature review are discussed in light of their implications for programs. Options for health programs are offered and examples of efforts to reduce maternal deaths are presented, with an emphasis on strategies to mobilize and adapt existing resources.     

Recombinant mono- and polyantigens to detect cytomegalovirus-specific immunoglobulin M in human sera by enzyme immunoassay

Serological detection of human cytomegalovirus (HCMV)-specific antibody varies greatly because of antigen composition and the lack of antigen standardization. Antigenic materials composed of single well-characterized viral proteins or portions of them, produced via molecular biology, have proven to be promising tools in improving serodiagnosis. We constructed a recombinant protein containing two regions of ppUL32 (p150) and half of ppUL44 (p52) and compared the immunoglobulin M (IgM) reactivity of this triple-antigen fusion protein with that of a double-antigen fusion protein containing the two ppUL32 fragments and that of a monoantigen fusion protein containing half of ppUL44. We also constructed and tested two other monoantigen fusion proteins containing a large fraction of ppUL80a and a fraction of ppUL83. More than 700 serum samples from different groups of immunocompetent and immunosuppressed subjects were tested for the presence of HCMV IgM by recombinant enzyme immunoassay (rec-EIA) and by a commercially available EIA. Western blotting (immunoblotting) and (in the case of immunosuppressed individuals) antigenemia tests by immunofluorescence and PCR of polymorphonuclear leukocytes were also carried out. The results obtained demonstrate that (i) the triple-antigen fusion protein can replace the individual proteins; (ii) the triple-antigen fusion protein cannot be used alone to replace the virus or infected cells in the serological detection of anti-CMV IgM; (iii) the addition of the fusion proteins containing portions of ppUL83 and ppUL80a is essential for the formation of an antigenic mixture that can replace the virus for the search of HCMV-specific IgM; (iv) rec-EIA is very specific and is more sensitive than the commercially available EIA, and the results obtained are consistent with those obtained by Western blotting; and (v) rec-EIA can reliably be used to detect HCMV-specific IgM in different groups of patients with active HCMV infection.     

Integrated systems I: Design principles

The following design principles are being used in an ongoing project to realize an integrated family of rule based systems that can be easily used separately or together in different combinations to solve problems common to many different disciplines. Some essential features of this family are:

1. Individual members can be used in the normal way as user-friendly rule based systems or they can be transparently invoked by other user-friendly rule based systems without interrogating users.
2. The knowledge (or rule) bases of key members do not mimic the perceived mode of human thought; therefore, they can predict events that cannot be predicted by the state-of-the-art alone.
3. The Law of Conservation of Mass/Energy is used to detect and correct computational errors.

     

Collaborative practice in pharmacy: Substance or semantics?

Medication use has become increasingly complex with expanding numbers of medications and growing populations of chronically ill patients. Changes in state and federal law and regulation have attempted to keep pace with the need for health care practitioners to oversee safe and effective medication use in various patient populations, including recent changes in Medicare. Pharmacists have experienced significant advancement in their education as well as in the roles they play in acute and chronic health care delivery. Over 44 states now recognize pharmacists' collaborative practice authority that allows for the initiation, monitoring, and modification of medication therapy for patients, typically under protocol. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

对专家级项目经理能力的评估——采用“讲故事”的方法（上）

首先从相关研究文献中找出专家级项目经理的特质，然后选择了十位经验丰富的项目经理，分别让其采用“讲故事”的方法讲述一次非凡的项目管理经历，然后对“故事”进行处理和分析，确定出项目经理应对相应情况所需要的特质和能力，并将其与从文献中得出的特质进行比较，得出最终的结论。