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Siddiqui, S.

Publications and source records attributed to Siddiqui, S..

2 recordsLinked to original sources

Policy lessons from spatiotemporal enrollment patterns of Payment for Ecosystem Service Programs in Argentina

Over the last 50 years, payment for ecosystem services schemes (PES) have been lauded as a market-based solution to curtail deforestation and restore degraded ecosystems. However, PES programs often fail to conserve sites under strong long-term deforestation pressures and allocate financial resources without having a sizeable impact on long-term land use change. Underperformance, in part, is likely due to adverse selection as landowners with land at the lowest threat from conversion or loss may be most likely to enroll or enrollment may be for short time-periods. Improving program performance to overcome adverse selection requires understanding attributes of landowners and their land across large scales to identify spatial and temporal enrollment patterns that drive adverse selection. In this paper, we examine these patterns in Argentinas PES program in the endangered Chaco forest ecoregion, which was established in 2007 under the National Forest Law. Our study area covers 252,319 km2. Among our most important findings is that large parcels of enrolled land and land owned by absentee landowners show greater evidence of spatiotemporal adverse selection than smaller plots of land and land owned by local actors. Furthermore, lands managed for conservation and restoration are more likely to be associated with adverse selection than lands that provide financial returns such as harvest of non-timber forest products, silviculture, and silvopasture. However, prior to recommending that PES programs focus on land uses with higher potential earnings, a greater understanding is needed of the degree to which these land uses meet ecological and biodiversity goals of PES programs. Because of this, we posit that a PES incorporating a market-based compensation strategy that varies with commodity prices, along with approaches that provide incentives for conservation and restoration land uses and enrollment of local landowners, could promote long-term conservation of endangered lands.

ecology

Structural variation detection by proximity ligation from FFPE tumor tissue

The clinical management and therapy of many solid tumor malignancies is dependent on detection of medically actionable or diagnostically relevant genetic variation. However, a principal challenge for genetic assays from tumors is the fragmented and chemically damaged state of DNA in formalin-fixed paraffin-embedded (FFPE) samples. From highly fragmented DNA and RNA there is no current technology for generating long-range DNA sequence data as is required to detect genomic structural variation or long-range genotype phasing. We have developed a high-throughput chromosome conformation capture approach for FFPE samples that we call \"Fix-C\", which is similar in concept to Hi-C. Fix-C enables structural variation detection from fresh and archival FFPE samples. We applied this method to 15 clinical adenocarcinoma and sarcoma specimens spanning a broad range of tumor purities. In this panel, Fix-C analysis achieves a 90% concordance rate with FISH assays - the current clinical gold standard. Additionally, we are able to identify novel structural variation undetected by other methods and recover long-range chromatin configuration information from these FFPE samples harboring highly degraded DNA. This powerful approach will enable detailed resolution of global genome rearrangement events during cancer progression from FFPE material, and inform the development of targeted molecular diagnostic assays for patient care.

genomics