Photoreceptor spectral sensitivity of the compound eyes of black soldier fly (Hermetia illucens) informing the design of LED-based illumination to enhance indoor reproduction.

Mating in the black soldier fly (BSF) is a visually mediated behaviour that under natural conditions occurs in full sunlight. Artificial light conditions promoting mating by BSF were designed based on the spectral characteristics of the compound eye retina. Electrophysiological measurements revealed that BSF ommatidia contained UV-, blue- and green-sensitive photoreceptor cells, allowing trichromatic vision. An illumination system for indoor breeding based on UV, blue and green LEDs was designed and its efficiency was compared with illumination by fluorescent tubes which have been successfully used to sustain a BSF colony for five years. Illumination by LEDs and the fluorescent tubes yielded equal numbers of egg clutches, however, the LED illumination resulted in significantly more larvae. The possibilities to optimize the current LED illumination system to better approximate the skylight illuminant and potentially optimize the larval yield are discussed.

Model-based optimization of viral capsid protein production in fed-batch culture of recombinant Escherichia coli.

An optimized fed-batch cultivation process for the production of the polyoma virus capsid protein VP1 in recombinant Escherichia coli BL21 bacteria is presented. The optimization procedure maximizing the amount of desired protein is based on a mathematical model. The model distinguishes an initial cell growth phase from a protein production phase initiated by inducer injection. A new approach to model the target protein formation rate was elaborated, where product formation is primarily dependent on the specific biomass growth rate. Lower growth rates led to higher specific protein concentrations. The model was identified from a series of fed-batch experiments designed for parameter identification purposes and possesses good prediction quality. Then the model was used to determine optimal open-loop control profiles by manipulating the substrate feed rates in both phases as well as the induction time. Feed-rate optimization has been solved using Pontryagin's maximum principle. The solution was validated experimentally. A significant improvement of the process performance index was achieved.

Synthesis of microbial poly(beta-hydroxybutyrate) modified with oligo(pentaerythritol ethoxylate) by Ralstonia eutropha.

Poly(beta-hydroxybutyrate) (PHB) modified with different amounts of pentaerythritol ethoxylate (PEE) has been synthesized using Ralstonia eutropha. The growth kinetics and the synthesis of PHB in the presence of PEE were modeled using appropriate differential equations for the mass balance of the two-stage process. The influence of PEE addition on the morphology of PHB was studied by various microscopic and scattering techniques. Light microscopic and wide-angle X-ray measurements indicated that the addition of PEE had a nucleating effect on the crystallization of PHB. The spherulite growth rate was widely independent of the PEE addition. The lamellae of PHB became more disordered when PEE was added as demonstrated by atomic force microscopy. Furthermore, small-angle X-ray data indicated a decrease in the long period with increasing PEE content of the modified PHB.

Village-based primary health care in the Central Highlands of Vietnam.

This paper describes the first year of an ongoing village health care and economic development project in the Krong Buk district of Dak Lak province in Vietnam's Central Highlands. The project serves 21 villages with a total population of just over 15,000. Most belong to ethnic minority groups. Physicians from the province capital of Boun Me Thuot were trained by a multi-disciplinary team of American health care workers to be trainers and supervisors of 21 village health care workers (VHWs). Two months later, a VHW from each village was trained in primary and preventive health care by the physician-supervisors. Since this initial training, each VHW has been provided with materials, medicines and monthly supervision by the physician-supervisors. The health care component has been complemented by an economic development project based on a system of small loans. Data from the first year of monthly reports and from a baseline survey are presented in this paper.

Changes in the health care system of Vietnam in response to the emerging market economy.

This paper discusses the impact on the Vietnamese health care system of the change from a centralized socialist system to a market economy. It discusses recent policies based on expectations in relation to actual outcomes, and the impacts these changes have had on health care delivery and health infrastructure in Vietnam. It has become clear that the private medical sector is draining resources from the State rather than complementing the weakened national health system. Impacts on health education, pharmaceuticals, infrastructure support, geographic distribution of physicians, and equity are all discussed in terms of recent economic changes. It is suggested that adjustments must be made to ensure adequate health care for all Vietnamese including those in rural areas and the urban poor. The State must develop mechanisms to support the national health service before further deterioration occurs.

Second primary cancers in breast cancer patients in Slovenia.

Data from the Cancer Registry of Slovenia were used in a cohort study to determine whether the incidence of second primary cancers in patients with first primary breast cancer differs from the incidence expected in the general population. Special interest was given to long-term survivors. The expected numbers of second primary cancers were calculated by multiplying the number of appropriate person-years at risk by the corresponding age- and calendar-period-specific cancer incidence rates for women in Slovenia. The risk of a second primary cancer was expressed as the standardized incidence ratio (SIR). Of the 8,917 patients newly diagnosed in the period 1961-85 and followed-up to the end of 1994, 547 (6.2 percent) developed second primary cancers, whereas 410 (4.7 percent) were expected (SIR = 1.3, 95 percent confidence interval [CI] = 1.2-1.4). The risk was higher among younger patients. In long-term survivors, the risk was increased significantly for second primary cancer of the breast (SIR = 1.4, CI = 1.1-1.7), lung cancer (SIR = 1.6, CI = 1.1-2.3), melanoma (SIR = 2.7, CI = 1.5-4.4) and non-melanoma skin cancers(SIR = 2.0, CI = 1.6-2.4), corpus uteri cancer(SIR = 1.6, CI = 1.2-2.1), ovarian cancer(SIR = 2.3, CI = 1.7-3.0), and thyroid cancer (SIR = 2.5, CI = 1.2-4.6). Our results confirm the findings of several cohort studies carried out in Europe, the United States, and Japan, indicating that breast cancer patients should be monitored carefully for the occurrence of second primary cancers.

Correlation of abdominal CT imaging with autopsy findings in patients with malignant tumors.

The value of abdominal computed tomography (CT) in diagnosing localized involvement of liver, pancreas, adrenals, and lymph nodes was evaluated in 117 patients with suspected or known malignant tumors by correlation with autopsy findings. Sensitivity, specificity, and accuracy of CT for localized liver disease was calculated to be 80% (84%), 96% (97%), and 90% (92%); for pancreatic tumors: 81% (86%), 98% (100%), and 95% (97%); for adrenal tumors: 65% (92%), 100% (100%), and 92% (98%); and for lymph node enlargement 75 (88%), 97% (98%), and 87% (94%), respectively. Results of routine evaluation could be improved, especially in the adrenal region, when scans were reevaluated by highly experienced examiners (results given in parenthesis). Computed tomography is a highly valuable diagnostic tool in the primary diagnosis and in the follow-up of tumor patients. The high costs are offset by a reduction in invasive procedures and a shortened hospital stay.

The influence of traditional medicine in shaping medical care practices in Vietnam today.

In Third World countries today one must have a knowledge of and appreciation for traditional medical beliefs and practices if one is to understand each nation's particular adaptation to a modern health care system. Taking the particular example of Vietnam, we discuss the current formal health care system and the traditional herbal medicines, dietary regulations and dermal techniques which are still important elements in the peoples' choice and perception of health care. There is then a discussion of how traditional medical beliefs and practices have shaped the practice of health care in Vietnam today.