Secreted production of an elastin-like polypeptide by Pichia pastoris

Elastin-like polypeptides (ELPs) are biocompatible designer polypeptides with inverse temperature transition behavior in solution. They have a wide variety of possible applications and a potential medical importance. Currently, production of ELPs is done at lab scale in Escherichia coli shake flask cultures. With a view to future large scale production, we demonstrate secreted production of ELPs in methanol-induced fed-batch cultures of Pichia pastoris and purification directly from the culture medium. The production of ELPs by P. pastoris proved to be pH dependent within the experimental pH range of pH 3 to 7, as an increasing yield was found in cultures grown at higher pH. Because ELP produced at pH 7 was partly degraded, a pH optimum for production of ELP was found at pH 6 with a yield of 255 mg of purified intact ELP per liter of cell-free medium

The James Webb Space Telescope Mission

Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least $4m$. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the $6.5m$ James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure

Muscle cramping during exercise : causes, solutions and questions remaining

Muscle cramp is a temporary but intense and painful involuntary contraction of skeletal muscle that can occur in many different situations. The causes of, and cures for, the cramps that occur during or soon after exercise remain uncertain, although there is evidence that some cases may be associated with disturbances of water and salt balance, while others appear to involve sustained abnormal spinal reflex activity secondary to fatigue of the affected muscles. Evidence in favour of a role for dyshydration comes largely from medical records obtained in large industrial settings, although it is supported by one large-scale intervention trial and by field trials involving small numbers of athletes. Cramp is notoriously unpredictable, making laboratory studies difficult, but experimental models involving electrical stimulation or intense voluntary contractions of small muscles held in a shortened position can induce cramp in many, although not all, individuals. These studies show that dehydration has no effect on the stimulation frequency required to initiate cramping and confirm a role for spinal pathways, but their relevance to the spontaneous cramps that occur during exercise is questionable. There is a long history of folk remedies for treatment or prevention of cramps; some may reduce the likelihood of some forms of cramping and reduce its intensity and duration, but none are consistently effective. It seems likely that there are different types of cramp that are initiated by different mechanisms; if this is the case, the search for a single strategy for prevention or treatment is unlikely to succeed.Publisher PDFPeer reviewe

Human trafficking and criminal proceedings in Portugal: discourses of professionals in the justice system

Author's personal copySince the adoption of the UN Trafficking Protocol in 2000, the predominant approach to combat human trafficking has been based on the criminalization of traffickers in conjunction with a concern for victims' protection. However, few empirical studies considered the effectiveness of those measures, which makes it difficult to understand why criminal cases of human trafficking generally result in few convictions. In Portugal, recent legislative changes have made the legal framework on human trafficking more comprehensive, inclusive and convergent with European directives. The effects of the implementation of those legislative changes on investigation and prosecution are still overlooked. The present study analyses the discourses of justice system professionals that concern the investigation and prosecution of human trafficking. It examines and identifies the factors that, in their perspective, block the recognition of the typifying elements of the crime of human trafficking and create obstacles to the prosecution and conviction of those crimes. Our findings suggest that legislative advances recognized by the participants need to be accompanied by other changes, some of a more systemic nature and others that are more specific. An efficient criminal procedure should include better legal phrasing of the means of evidence of human trafficking that is supported by objective instruments for this to be considered valid; the centralization of proof that the testimony of the victim has to overcome; specialized professional training of an ongoing nature; an efficient cooperation between the various law enforcement agencies at the national and international levels, with public prosecution services and magistrates; a greater clarification of the condition of the special vulnerability of victims and an informed perspective regarding the global nature of the phenomenon of human trafficking, one that is also sensitive towards the victim (e.g., in relation to the victims' vulnerability, illegal status, and their difficulties in teThis study was conducted at Psychology Research Centre, University of Minho, and supported by the Commission for Citizenship and Gender Equality (CIG), Presidency of the Council of Ministers. The authors also thank Eunice Seixas for technical support.info:eu-repo/semantics/publishedVersio