Sustaining upgrading in agricultural value chains?:State-led value chain interventions and emerging bifurcation of the South Indian smallholder tea sector

The Global Value Chain (GVC) approach has emerged as a novel methodological device for analysing economic globalization and international trade. The suitability of the chain metaphor and strategies for moving up the ladder of GVCs (“upgrade”) is widely echoed in international development agencies and public agencies in the Global South. Most of the existing GVC studies focus on new forms of firm-to-firm relationships and the role of lead firms and chain governance in defining upgrading opportunities. This paper examines the role of the state and local institutional initiatives in promoting upgrading in agricultural GVCs originating in rural areas of the Global South. The paper draws on research conducted in the South Indian smallholder tea sector. The paper argues that successful forms of state-led chain interventions not only contribute to upgrading of the smallholder-brought leaf factory strand of the GVC originating in the South Indian tea sector, but might also result in increasing bifurcation of smallholders integrated into high-margin markets through prominent bought leaf factories and a mass of “others” outside this tightly coordinated strand of the tea value chain

Expression of a p16INK4a-specific ribozyme downmodulates p16INK4a abundance and accelerates cell proliferation

AbstractThe p16INK4a tumor suppressor negatively regulates progression through the G1 phase of the mammalian cell cycle. To mimic the downmodulation of p16INK4a commonly seen in cancer, we designed and characterized a hammerhead ribozyme against exon E1α of the murine p16INK4a transcript. Stable expression of the ribozyme in murine erythroleukemia (MEL) cells reduced the endogenous p16INK4a protein by more than 70% and significantly accelerated cell cycle progression. The specificity and efficiency of our new ribozyme suggest its possible application in elucidating the role of p16INK4a in fundamental biological processes including homeostatic tissue renewal, protection against oncogenic transformation, and cellular senescence

Repurposing phenothiazines for cancer therapy: compromising membrane integrity in cancer cells

The limitations of current cancer therapies, including the increasing prevalence of multidrug resistance, underscore the urgency for more effective treatments. One promising avenue lies in the repurposing of existing drugs. This review explores the impact of phenothiazines, primarily used as antipsychotic agents, on key mechanisms driving tumor growth and metastasis. The cationic and amphiphilic nature of phenothiazines allows interaction with the lipid bilayer of cellular membranes, resulting in alterations in lipid composition, modulation of calcium channels, fluidity, thinning, and integrity of the plasma membrane. This is especially significant in the setting of increased metabolic activity, a higher proliferative rate, and the invasiveness of cancer cells, which often rely on plasma membrane repair. Therefore, properties of phenothiazines such as compromising plasma membrane integrity and repair, disturbing calcium regulation, inducing cytosolic K-RAS accumulation, and sphingomyelin accumulation in the plasma membrane might counteract multidrug resistance by sensitizing cancer cells to membrane damage and chemotherapy. This review outlines a comprehensive overview of the mechanisms driving the anticancer activities of phenothiazines derivates such as trifluoperazine, prochlorperazine, chlorpromazine, promethazine, thioridazine, and fluphenazine. The repurposing potential of phenothiazines paves the way for novel approaches to improve future cancer treatment

Direct observations of the vacancy and its annealing in germanium

Weakly n-type doped germanium has been irradiated with protons up to a fluence of 3×10 exp 14 cm exp −2 at 35 K and 100 K in a unique experimental setup. Positron annihilation measurements show a defect lifetime component of 272±4 ps at 35 K in in situ positron lifetime measurements after irradiation at 100 K. This is identified as the positron lifetime in a germanium monovacancy. Annealing experiments in the temperature interval 35–300 K reveal two annealing stages. The first at 100 K is tentatively associated with the annealing of the Frenkel pair, the second at 200 K with the annealing of the monovacancy. Above 200 K it is observed that mobile neutral monovacancies form divacancies, with a positron lifetime of 315 ps.Peer reviewe

Light emission from silicon with tin-containing nanocrystals

Tin-containing nanocrystals, embedded in silicon, have been fabricated by growing an epitaxial layer of Si_{1-x-y}Sn_{x}C_{y}, where x = 1.6 % and y = 0.04 %, followed by annealing at various temperatures ranging from 650 to 900 degrees C. The nanocrystal density and average diameters are determined by scanning transmission-electron microscopy to ~ 10^{17} cm^{-3} and ~ 5 nm, respectively. Photoluminescence spectroscopy demonstrates that the light emission is very pronounced for samples annealed at 725 degrees C, and Rutherford back-scattering spectrometry shows that the nanocrystals are predominantly in the diamond-structured phase at this particular annealing temperature. The origin of the light emission is discussed.Comment: 5 pages, 3 figures, submitted to AIP Advance