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Though surface water quality has been monitored in southern Peru over the past and current century, it has been implemented by multiple organizations. The data lacks a centralized repository and access requires logistical and temporal hurdles associated with official requests. A substantial portion of the data has not been quality assured and is in difficult-to-access formats such as scanned PDF documents. These obstacles collectively make it challenging to maximize the impact of these monitoring efforts such as efficiently evaluating long-term water quality trends. To address this opportunity, we gathered available surface water quality information from five watersheds in the Arequipa Region of southern Peru: Camaná, Chili, Ocoña, Tambo, and Yauca. The effort required entry of more than 130,000 records of water quality properties across 274 monitoring stations with data including the concentration of select nutrients, metals, organic compounds, and biological taxa. The water quality records in the Chili watershed go back as far as 1905, while data for the other watersheds was largely confined to the years 2012–2021. This document describes how the surface water quality information was assimilated with quality control and provides a centralized Excel database so that the data can be efficiently used for research and decision making purposes.

Land surface temperature (LST) is one of the most important variables in the physical processes of surface energy and water balance. The temporal behavior of LST was analyzed between the latitudes 32°00′ S and 34°24′ S (Valparaíso and Metropolitana regions of Chile) for three summer months (December, January, and February) in the 2000–2017 period, using the Terra MODIS image information and applying the Mann–Kendall test. The results show an increase in LST in the study area, particularly in the Andes mountain range in January (5240 km2), which mainly comprises areas devoid of vegetation and eternal snow and glaciers, and are zones that act as water reserves for the capital city of Santiago. Similarly, vegetated areas such as forests, grasslands, and shrublands also show increasing trends in LST but over smaller surfaces. Because this study is regional, it is recommended to improve the spatial and temporal resolutions of the images to obtain conclusions on more local scales.

This paper uses a Bertrand duopoly model application and derives a high fructose corn syrup (HFCS) price reaction function that shows the response of the price of HFCS to changes in the price of sugar. It conducts cointegration analysis and assesses the performance of the HFCS price reaction model by estimating a Dynamic Ordinary Least-Squares model. It finds that the prices of HFCS-55, sugar, and corn are cointegrated over the period 1981:1 to 2017:12. The estimated long-run relationship shows that a one percent increase in the price of sugar increases the price of HFCS-55 by 0.19 percent. Additionally, the price of corn has a positive effect on the price of HFCS-55. The model and the results offer important insights for antitrust litigation.

To better query regional sources of metal(loid) exposure in an under-communicated region, available scientific literature from 50 national universities (undergraduate and graduate theses and dissertations), peer-reviewed journals, and reports published in Spanish and English were synthesized with a focus on metal(loid) bioaccumulation in Peruvian food and medicinal products utilized locally. The study considered 16 metal(loid)s that are known to exert toxic impacts on humans (Hg, Al, Sb, As, Ba, Be, Cd, Cr, Sn, Ni, Ag, Pb, Se, Tl, Ti, and U). A total of 1907 individual analyses contained within 231 scientific publications largely conducted by Peruvian universities were analyzed. These analyses encompassed 239 reported species classified into five main food/medicinal groups—plants, fish, macroinvertebrates and mollusks, mammals, and “others” category. Our benchmark for comparison was the World Health Organization (Codex Alimentarius) standards. The organisms most frequently investigated included plants such as asparagus, corn, cacao, and rice; fish varieties like trout, tuna, and catfish; macroinvertebrates and mollusks including crab and shrimp; mammals such as alpaca, cow, chicken eggs, and milk; and other categories represented by propolis, honey, lichen, and edible frog. Bioaccumulation-related research increased from 2 to more than 25 publications per year between 2006 and 2022. The results indicate that Peruvian food and natural medicinal products can have dangerous levels of metal(loid)s, which can cause health problems for consumers. Many common and uncommon food/medicinal products and harmful metals identified in this analysis are not regulated on the WHO’s advisory lists, suggesting the urgent need for stronger regulations to ensure public safety. In general, Cd and Pb are the metals that violated WHO standards the most, although commonly non-WHO regulated metals such as Hg, Al, As, Cr, and Ni are also a concern. Metal concentrations found in Peru are on many occasions much higher than what has been reported elsewhere. We conclude that determining the safety of food/medicinal products is challenging due to varying metal concentrations that are influenced not only by metal type but also geographical location. Given the scarcity of research findings in many regions of Peru, urgent attention is required to address this critical knowledge gap and implement effective regulatory measures to protect public health.

The p21-activated kinase 1 (PAK1) is required for insulin-stimulated glucose uptake in skeletal muscle cells. However, whether PAK1 regulates skeletal muscle mitochondrial function, which is a central determinant of insulin sensitivity, is unknown. Here, the effect of modulating PAK1 levels (knockdown via siRNA, overexpression via adenoviral transduction, and/or inhibition of activation via IPA3) on mitochondrial function was assessed in normal and/or insulin-resistant rat L6.GLUT4myc and human muscle (LHCN-M2) myotubes. Human type 2 diabetes (T2D) and non-diabetic (ND) skeletal muscle samples were also used for validation of the identified signaling elements. PAK1 depletion in myotubes decreased mitochondrial copy number, respiration, altered mitochondrial structure, downregulated PGC1α (a core regulator of mitochondrial biogenesis and oxidative metabolism) and PGC1α activators, p38 mitogen-activated protein kinase (p38MAPK) and activating transcription factor 2 (ATF2). PAK1 enrichment in insulin-resistant myotubes improved mitochondrial function and rescued PGC1α expression levels. Activated PAK1 was localized to the cytoplasm, and PAK1 enrichment concurrent with p38MAPK inhibition did not increase PGC1α levels. PAK1 inhibition and enrichment also modified nuclear phosphorylated-ATF2 levels. T2D human samples showed a deficit for PGC1α, and PAK1 depletion in LHCN-M2 cells led to reduced mitochondrial respiration. Overall, the results suggest that PAK1 regulates muscle mitochondrial function upstream of the p38MAPK/ATF2/PGC1α-axis pathway.

This paper uses an application of the Bertrand model to explain the relationship between HFCS deliveries and the prices of HFCS-42 and sugar. It finds that the HFCS deliveries and the prices of HFCS-42 and refined sugar are cointegrated over the period 1994:q1-2020:q1. The main results, based on the estimated long-run elasticities, show that a one percent increase in the price of HFCS-42 decreases HFCS deliveries by 0.153 percent. One implication of this result is that it would be helpful for the HFCS industry to prevent large increases in the HFCS price, which would prevent large decreases in HFCS deliveries and its share in the U.S. sweetener market. In addition, the price of sugar does not have a significant effect on HFCS deliveries.

Skeletal muscle accounts for ~80% of insulin-stimulated glucose uptake. The Group I p21–activated kinase 1 (PAK1) is required for the non-canonical insulin-stimulated GLUT4 vesicle translocation in skeletal muscle cells. We found that the abundances of PAK1 protein and its downstream effector in muscle, ARPC1B, are significantly reduced in the skeletal muscle of humans with type 2 diabetes, compared to the non-diabetic controls, making skeletal muscle PAK1 a candidate regulator of glucose homeostasis. Although whole-body PAK1 knockout mice exhibit glucose intolerance and are insulin resistant, the contribution of skeletal muscle PAK1 in particular was unknown. As such, we developed inducible skeletal muscle-specific PAK1 knockout (skmPAK1-iKO) and overexpression (skmPAK1-iOE) mouse models to evaluate the role of PAK1 in skeletal muscle insulin sensitivity and glucose homeostasis. Using intraperitoneal glucose tolerance and insulin tolerance testing, we found that skeletal muscle PAK1 is required for maintaining whole body glucose homeostasis. Moreover, PAK1 enrichment in GLUT4-myc-L6 myoblasts preserves normal insulin-stimulated GLUT4 translocation under insulin resistance conditions. Unexpectedly, skmPAK1-iKO also showed aberrant plasma insulin levels following a glucose challenge. By applying conditioned media from PAK1-enriched myotubes or myoblasts to β-cells in culture, we established that a muscle-derived circulating factor(s) could enhance β-cell function. Taken together, these data suggest that PAK1 levels in the skeletal muscle can regulate not only skeletal muscle insulin sensitivity, but can also engage in tissue crosstalk with pancreatic β-cells, unveiling a new molecular mechanism by which PAK1 regulates whole-body glucose homeostasis.

Type 1 diabetes (T1D) arises secondary to immune-driven destruction of pancreatic β-cells and manifests as insulin-deficient hyperglycemia. We showed that oral vaccination with live attenuated Salmonella, which simultaneously delivers autoantigens and a TGFβ expression vector to immune cells in the gut mucosa, provides protection against the progression of T1D in non-obese diabetic (NOD) mice. In this study we employed the Sleeping Beauty (SB) transposon system that is composed of a transposase and transposon encoding the td-Tomato to express red fluorescent protein (RFP) to permanently mark the cells that take up the Salmonella vaccine. After animal vaccination, the transposon labeled-dendritic cells (DCs) with red fluorescence appeared throughout the secondary lymphoid tissues. Furthermore, Sleeping Beauty containing tgfβ1 gene (SB-tgfβ1) co-expressed TGFβ and RFP. The labeled DCs were detected predominantly in Peyer’s patches (PP) and mesenteric lymph nodes (MLN) and expressed CD103 surface marker. CD103+ DCs induced tolerogenic effects and gut homing. TGFβ significantly increased programmed death-ligand-1 (PDL-1 or CD274) expression in the DCs in the MLN and PP of treated mice. Also, TGFβ increased cytotoxic T-lymphocyte-associated protein-4 (CTLA-4) levels in CD4+ cells in MLN and PP. Interestingly, DCs increased in all lymphatic organs of mice vaccinated with oral live Salmonella-based vaccine expressing preproinsulin (PPI), in combination with TGFβ, IL10, and subtherapeutic-doses of anti-CD3 mAb compared with vehicle-treated mice. These DCs are mostly tolerogenic in MLN and PP. Furthermore the DCs obtained from vaccine-treated but not vehicle-treated mice suppressed in vitro T cell proliferation. These data suggest that the MLN and the PP are a central hub for the beneficial anti-diabetic effects of an oral Salmonella-based vaccine prevention of diabetes in rodents.

This study1 uses survey data to assess the effect of oxen as draft animals on agricultural productivity and farm agricultural income in Nicaragua during the year 2017. The results suggest that farms that use oxen to plow the land have higher bean productivity than farms that use stick to plant crops. On average, using oxen increases farm’s bean output by 7.75 100-pound bags, and hiring oxen increases farm’s bean output by 8.5 100-pound bags. Also, using or hiring oxen increases total farm planted area. The main finding about the effect of oxen to plow the land through farm planted area on agricultural farm gross income suggests that using oxen to plow the land increases agricultural farm gross income by 18.13 percent, and that hiring oxen increases agricultural farm gross income by 25.55 percent.

Autoimmune diseases such as type 1 diabetes (T1D) involve the loss of regulatory mechanisms resulting in increased tissue-specific cytotoxicity. The result is destruction of pancreatic insulin-producing β-cells and loss of glucose homeostasis. We are developing a novel oral vaccine using live attenuated Salmonella to deliver TGFβ, IL10, and the diabetic autoantigen preproinsulin combined with low-doses of anti-CD3 mAb. Here we show that oral administration of Salmonella-based anti-CD3 mAb combined therapy reverses new-onset T1D in non-obese diabetic (NOD) mice. The therapeutic effect of the combined therapy was associated with induction of immune suppressive CD4+CD25+Foxp3+ Treg and CD4+CD49b+LAG3+ Tr1 cells. In adoptive transfer experiments, adding or depleting Treg or Tr1 cells indicated that both are important for preventing diabetes in combined therapy-treated mice, but that Tr1 cells may have a more central role. Furthermore, induced Tr1 cells were found to be antigen-specific responding to peptide stimulation by secreting tolerance inducing IL10. These preclinical data demonstrate a role for Treg and Tr1 cells in combined therapy-mediated induction of tolerance in NOD mice. These results also demonstrate the potential of oral Salmonella-based combined therapy in the treatment of early T1D.