Impact of community-based forest management and joint forest management on forest resource base and local peoples' livelihoods : case studies from Tanzania

Copublished with Centre for Applied Social Sciences, University of ZimbabweCASS/PLAAS occasion paper seriesIn recent years, there has been a move in eastern and southern African countries from centralised and state-driven management of natural resources towards decentralised and people-centred based regimes. In Tanzania, the inception of the 1998 national forest policy has led to institutionalisation of community-based forest management (CBFM) and joint forest management (JFM). A number of years later, it is worth assessing the impact of this policy on the resource base and people’s livelihoods. This paper uses two case studies of forest reserves under participatory forest management to explore this issue. Secondary data was gathered from various studies conducted in those two forest reserves. In addition to the analysis carried out by the various authors, further analysis involving content and structural analysis and synthesis of documented information was done. The results of the study revealed that CBFM at Duru-Haitemba had a positive impact on the resource base and people’s livelihoods – the forest is healthier than before and people are satisfied with the products they collect from the forests. On the other hand, the impact of JFM at Kwizu Forest Reserve has not yet produced desirable results since illegal activities are still rampant and, apparently, forest exploitation has increased instead of decreasing. The reasons behind the success at Duru-Haitemba and relative failure at Kwizu are varied, but are most probably linked to ownership of resources and law enforcement. Clear definition of rights, returns and responsibilities and adequate incentives are important for sustainability of people-centred management of natural resources

Impact of Chlamydia trachomatis in the reproductive setting: British Fertility Society Guidelines for practice

Chlamydia trachomatis infection of the genital tract is the most common sexually transmitted infection and has a world-wide distribution. The consequences of infection have an adverse effect on the reproductive health of women and are a common cause of infertility. Recent evidence also suggests an adverse effect on male reproduction. There is a need to standardise the approach in managing the impact of C. trachomatis infection on reproductive health. We have surveyed current UK practice towards screening and management of Chlamydia infections in the fertility setting. We found that at least 90% of clinicians surveyed offered screening. The literature on this topic was examined and revealed a paucity of solid evidence for estimating the risks of long-term reproductive sequelae following lower genital tract infection with C. trachomatis. The mechanism for the damage that occurs after Chlamydial infections is uncertain. However, instrumentation of the uterus in women with C. trachomatis infection is associated with a high risk of pelvic inflammatory disease, which can be prevented by appropriate antibiotic treatment and may prevent infected women from being at increased risk of the adverse sequelae, such as ectopic pregnancy and tubal factor infertility. Recommendations for practice have been proposed and the need for further studies is identified

Risk of cancer in children and young adults conceived by assisted reproductive technology

STUDY QUESTION: Do children conceived by ART have an increased risk of cancer? SUMMARY ANSWER: Overall, ART-conceived children do not appear to have an increased risk of cancer. WHAT IS KNOWN ALREADY: Despite the increasing use of ART, i.e. IVF or ICSI worldwide, information about possible long-term health risks for children conceived by these techniques is scarce. STUDY DESIGN, SIZE, DURATION: A nationwide historical cohort study with prospective follow-up (median 21 years), including all live-born offspring from women treated with subfertility treatments between 1980 and 2001. PARTICIPANTS/MATERIALS, SETTING, METHODS: All offspring of a nationwide cohort of subfertile women (OMEGA study) treated in one of the 12 Dutch IVF clinics or two fertility clinics. Of 47 690 live-born children, 24 269 were ART-conceived, 13 761 naturally conceived and 9660 were conceived naturally or through fertility drugs, but not by ART. Information on the conception method of each child and potential confounders were collected through the mothers’ questionnaires and medical records. Cancer incidence was ascertained through linkage with The Netherlands Cancer Registry from 1 January 1989 until 1 November 2016. Cancer risk in ART-conceived children was compared with risks in naturally conceived children from subfertile women (hazard ratios [HRs]) and with the general population (standardized incidence ratios [SIRs]). MAIN RESULTS AND THE ROLE OF CHANCE: The median follow-up was 21 years (interquartile range (IQR): 17–25) and was shorter in ART-conceived children (20 years, IQR: 17–23) compared with naturally conceived children (24 years, IQR: 20–30). In total, 231 cancers were observed. Overall cancer risk was not increased in ART-conceived children, neither compared with naturally conceived children from subfertile women (HR: 1.00, 95% CI 0.72–1.38) nor compared with the general population (SIR = 1.11, 95% CI: 0.90–1.36). From 18 years of age onwards, the HR of cancer in ART-conceived versus naturally conceived individuals was 1.25 (95% CI: 0.73–2.13). Slightly but non-significantly increased risks were observed in children conceived by ICSI or cryopreservation (HR = 1.52, 95% CI: 0.81–2.85; 1.80, 95% CI: 0.65–4.95, respectively). Risks of lymphoblastic leukemia (HR = 2.44, 95% CI: 0.81–7.37) and melanoma (HR = 1.86, 95% CI: 0

Transient quinonimines and 1,4-benzothiazines of pheomelanogenesis: new pulse radiolytic and spectrophotometric evidence

Biosynthetic and model in vitro studies have shown that pheomelanins, the distinctive pigments of red human hair, arise by oxidative cyclization of cysteinyldopas mainly 5-S-cysteinyldopa (1) via a critical o-quinonimine intermediate, which rearranges to unstable 1,4-benzothiazines. To get new evidence for these labile species, fast time resolution pulse radiolytic oxidation by dibromide radical anion of a suitable precursor, the dihydro-1,4-benzothiazine-3-carboxylic acid 7 was performed in comparison with that of 1. In the case of 7, dibromide radical anion oxidation leads over a few microseconds (k = 2.1 x 10(9) M-1 s(-1)) to a phenoxyl radical (lambda(max) 330 nm, epsilon = 6300 M-1 cm(-1)) which within tens of milliseconds gives rise with second-order kinetics (2k = 2.7 X 10(7) M-1 s(-1)) to a species exhibiting an absorption maximum at 540 nm (epsilon = 2200 M-1 cm(-1)). This was formulated as the o-quinonimine 3 arising from disproportionation of the initial radical. The quinonimine chromophore is converted over hundreds of milliseconds (k = 6.0 s(-1)) to a broad maximum at around 330 nm interpreted as due to a 1,4-benzothiazine or a mixture of 1,4-benzothiazines, which as expected are unstable and subsequently decay over a few seconds (k = 0.5 s(-1)). Interestingly, the quinonimine is observed as a labile intermediate also in the alternative reaction route examined, involving cyclization of the o-quinone (lambda(max) 390 nm, epsilon = 6900 M-1 cm(-1)) arising by disproportionation (2k = 1.7 X 10(8) M-1 s(-1)) of an o-semiquinone (lambda(max) 320 nm, epsilon = 4700 M-1 cm(-1)) directly generated by dibromide radical anion oxidation of 1. Structural formulation of the 540 nm species as an o-quinonimine was further supported by rapid scanning diode array spectrophotometric monitoring of the ferricyanide oxidation of a series of model dihydrobenzothiazines

The optical sensitivity of compound eyes: theory and experiment compared

The Land sensitivity equation is a well-known tool for comparing optical performance between eyes. Despite this, the equation has never been experimentally tested. Here, we present, to our knowledge, the first experimental validation of the equation. We have investigated different insect species active at different intensities, and possessing different types of compound eyes, to compare ratios of calculated sensitivities to ratios determined experimentally. Experimental optical sensitivities were measured by adjusting the intensity of an external light source until photoreceptors in the different eyes produced roughly equal numbers of photon responses (‘bumps’) per second. The sensitivity ratios obtained in this manner agree well with those obtained using the equation. We conclude that the Land equation remains an excellent tool for comparing sensitivities between different eyes