Copper vapor laser unstable resonator oscillator and oscillator-amplifier characteristics

We have studied the properties of copper vapor lasers configured as oscillators with unstable resonator optics and as power amplifiers. With the unstable resonator, a 26-fold reduction in the oscillator beam divergence has been achieved over the value observed with stable optics without any power degradation. Time-dependent beam divergence effects in the unstable resonator have also been measured and explained. Small-signal gain, saturation fluence, and available stored energy density parameters have also been measured in oscillator amplifier experiments for both the 510.6 and 578.2 nm transitions as a function of the copper number density. These results quantify the maximum power per unit length available from these devices and furthermore, demonstrate efficient extraction of power from copper vapor lasers operated as amplifiers.     

Smooth-pursuit eye movement dysfunction and liability for schizophrenia: Implications for genetic modeling.

41 nonpsychiatric Ss, 38 probands with schizophrenia, and 99 of their relatives were studied. Oculomotor functioning was bimodally distributed for probands and relatives. Oculomotor dysfunction was not present in all families with a schizophrenic proband. In those families in which it was present, there were significant phenotypic correlations between oculomotor functioning and schizophrenia-related characteristics. The patterns of familial resemblance in the families in whom oculomotor dysfunction was present were consistent with nonadditive genetic variance contributing both to oculomotor dysfunction and to the relationship between oculomotor dysfunction and clinical symptoms. These results suggest that schizophrenia may be etiologically heterogeneous and that oculomotor dysfunction may help to identify nonadditive genetic variance for this disorder. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Filamentous actin disruption and diminished inositol phosphate response in gingival fibroblasts caused by Treponema denticola

A large body of evidence suggests that the neuroendocrine axis plays a major role in the reproductive aging of female rats. Since increased hypothalamic neuropeptide Y (NPY) neurosecretion is crucial in the preovulatory LH discharge in young rats, we tested the hypothesis that diminution in the preovulatory LH surge in middle-aged (MA) rats may be due to altered neurosecretory activity in NPYergic neurons. In Exp 1, we examined NPY levels in six microdissected hypothalamic nuclei, including median eminence (ME), arcuate nucleus (ARC), and medial preoptic area (MPOA), at 1000, 1200, 1400, 1600, 1800, 2000, or 2200 h on the day of proestrus in young (2.5- to 3-month old) and MA (7- to 9-month old) regularly cycling rats. At 1000 h, ME NPY levels in young rats were significantly lower than those in MA rats. In young rats, the ME NPY levels were significantly increased at 1400 h before the LH surge in the afternoon and thereafter decreased progressively during the interval of the LH surge. In MA rats, however, ME NPY levels decreased in the afternoon in association with an attenuated LH surge. In addition, in the ARC and MPOA, the other hypothalamic sites associated with induction of LH surge, NPY levels increased before and during the LH surge in young rats, no change in NPY levels in these nuclei was observed in association with the attenuated LH surge in MA rats. Also, NPY levels in the ARC and MPOA during the afternoon were significantly lower in MA compared with those in young animals. These results demonstrated the absence of an antecedent increase in NPY levels, specifically in the ME and ARC, during the afternoon of proestrus in MA animals. In a second experiment, we evaluated whether the absence of dynamic changes in NPY levels in the ME and ARC in MA rats was due to altered hypothalamic NPY gene expression. Regularly cycling young (2.5- to 3-month-old) and MA (8- to 10-month-old) rats were killed at 1000, 1200, 1400, 1600, 1800, 2000, or 2200 h on the day of proestrus. The medial basal hypothalamus was processed for prepro-NPY messenger RNA (mRNA) measurement by ribonuclease protection assay. In young rats, prepro-NPY mRNA levels were significantly increased at 1200 h and remained elevated throughout the afternoon. In contrast, in MA rats prepro-NPY mRNA levels remained unchanged before and during the attenuated LH surge. These results clearly indicate that the augmentation in NPY neuronal activity before and during the LH surge seen in young rats fails to manifest itself in middle-aged rats. As hypothalamic NPY participates in the induction of LHRH surge, our results suggest that reduced LHRH and LH surges in MA rats may be due to diminution in NPY secretion in these animals.     

Right-ventricular function as assessed by two radionuclide techniques: concise communication

The gated semiautomated first pass and non-gated manual first pass methods of right ventricular ejection fraction calculation were compared. It was found that the gated first pass study was the simplest and fastest to process and was overall judged to give at least as much information as the other technique.     

Internet-based expert systems

The Internet offers a large potential for delivery of various information-based services, including the services of intelligent applications. As the availability of the Internet has grown, its value as a medium for the delivery of expert systems in particular has increased. There are now a large number of expert systems available on the Internet, including applications in industry, medicine, science and government. Though the Internet provides several advantages for expert system development, it also presents some special problems. These advantages and disadvantages are explored in more detail in this paper. The paper also presents a review of several Internet-based expert systems with a representative sample of publicly available applications, and a discussion of typical tools for developing Internet-based expert systems. A case study of an Internet-based expert system is presented as well.     

Low‐cost display assembly and interconnect using ink‐jet printing technology

Ink‐jet printing methods may be utilized for efficient micro‐deposition of solder bumps, spacer balls, and adhesive sealant/bond lines, as well as liquid‐crystal and color‐filter droplets, in the manufacture of display panels. Advantages realized by this approach include data‐driven low‐cost high‐speed non‐contact environmentally friendly processing.     

Geologic materials' response to shaped charge penetration

A comprehensive experimental effort was recently conducted to evaluate the penetration performance of oilwell perforating charges into stressed and unstressed Berea sandstone cores. Rock confining pressure (P_c) and pore fluid pressure (P_p) were varied from ambient to 10,000 psi, to simulate downhole stress environments typically experienced by subterranean reservoir rock. Experiments yielded a generally inverse correlation between penetration depth and effective stress (σ_eff). However, a new definition of effective stress is proposed. Historically, the perforating community has defined σ_eff = P_c − P_p, but a new treatment (σ_eff = P_c − aP_p; a = 0.5) better fits both present and published historical penetration results. These findings culminate an initial application of combined penetration mechanics and rock mechanics analyses to the investigation of shaped charge penetration into geologic materials. Future work will address different rock types, additional poroelastic quantities, and dynamic effects as they contribute to pressure-induced strengthening of target rock.     

More ‘crop per drop’: constraints and opportunities for precision irrigation in European agriculture

Dwindling water supplies, increasing drought frequency and uncertainties associated with a changing climate mean Europe's irrigated agriculture sector needs to improve water efficiency and produce more 'crop per drop'. This paper summarizes the drivers for change, and the constraints and opportunities for improving agricultural water management through uptake of precision irrigation technologies. A multi‐disciplinary and integrated approach involving irrigation engineers, soil scientists, agronomists and plant physiologists will be needed if the potential for precision irrigation within the field crop sector is to be realized. © 2013 Society of Chemical Industry     

中国标准化行政管理者访问ASTM国际组织

7月13日至14日,中国标准化行政管理者代表团访问了ASTM国际组织总部。代表团的主要成员有中国国家标准化管理委员会(SAC)主任李忠海、国家质量监督检验检疫总局(AQSIQ)的代表以及中国国务院的成员。此次访问的目的是了解美国标准制定过程及其自愿性标准如何在美国法规中得到采用。访问ASTM国际组织是代表团访问美国和加拿大标准制定组织和政府部门的主要任务之一。在访问ASTM国际组织总部期间,以李忠海主任为团长的代表团就美国自愿协调一致标准体系与倍受关注的先导私人部门标准制定组织,如ASTM国际组织的作用等交换了看法。A S…