Search

The city of Arequipa, the second most important city in Perú, faces numerous daunting challenges, including high-intensity but short-in-duration rainfalls that leads to floods and the swelling of the Chili River (mud and landslides). This situation aggravates the vulnerability of the population settled on the margins of the gorges and gullies, due to little or no territorial planning from public institutions. The local news evidence negligence every year, both in terms of human lives and infrastructure loss. The frequency of these events has increased with time and that is the reason for prompting the establishment of rainfall thresholds and the compilation of a 41-year record (1981-2021), with the aim of informing about the dangerousness of an adverse meteorological phenomenon, either predicted or in progress. For the hydrological model, the authors used the highest 24-hour precipitation data from the SENAMHI's stations (National Service of Meteorology and Hydrology of Peru) to generate the liquid hydrograph for different return periods with the Hydrologic model of HEC-HMS. Soil mechanics studies were also carried out to determine the rheological parameters of the non-Newtonian flow and then calibrate through historical events in a hydraulic model of HEC-RAS. Finally, cartographic maps in QGIS were prepared to evaluate the hazard zones flooding in the Del Pato, San Lázaro, Venezuela and Los Incas gullies.

Abstract In high-altitude regions, such as the Peruvian Andes, understanding the transformation of precipitation types under climate change is critical to the sustainability of water resources and the survival of glaciers. In this study, we investigate the distribution and types of precipitation on a tropical glacier in the Peruvian Central Andes. We utilized data from an optical-laser disdrometer and compact weather station installed at 4709 m ASL, combined with future climate scenarios from the CMIP6 project, to model potential future changes in precipitation types. Our findings highlight that increasing temperatures could lead to significant reductions in solid-phase precipitation, including snow, graupel and hail, with implications for the mass balance of Andean glaciers. For instance, a 2 °C rise might result in less than 10% of precipitation as solid, in regard to the present day, transforming the hydrological processes of the region. The two future climate scenarios from the CMIP6 project, SSP2-4.5 and SSP5-8.5, offer a broad perspective on potential climate outcomes that could impact precipitation patterns in the Andes. Our study underscores the need to revisit and expand our understanding of high-altitude precipitation in the face of climate change, paving the way for improved water resource management strategies and sustainable glacier preservation efforts in these fragile ecosystems.

Abstract Background Reduction of adult hippocampal neurogenesis is an early critical event in Alzheimer’s disease (AD), contributing to progressive memory loss and cognitive decline. Reduced levels of the nucleoporin 153 (Nup153), a key epigenetic regulator of NSC stemness, characterize the neural stem cells isolated from a mouse model of AD (3×Tg) (AD-NSCs) and determine their altered plasticity and gene expression. Methods Nup153-regulated mechanisms contributing to NSC function were investigated: (1) in cultured NSCs isolated from AD and wild type (WT) mice by proteomics; (2) in vivo by lentiviral-mediated delivery of Nup153 or GFP in the hippocampus of AD and control mice analyzing neurogenesis and cognitive function; (3) in human iPSC-derived brain organoids obtained from AD patients and control subjects as a model of neurodevelopment. Results Proteomic approach identified Nup153 interactors in WT- and AD-NSCs potentially implicated in neurogenesis regulation. Gene ontology (GO) analysis showed that Nup153-bound proteins in WT-NSCs were involved in RNA metabolism, nuclear import and epigenetic mechanisms. Nup153-bound proteins in AD-NSCs were involved in pathways of neurodegeneration, mitochondrial dysfunction, proteasomal processing and RNA degradation. Furthermore, recovery of Nup153 levels in AD-NSCs reduced the levels of oxidative stress markers and recovered proteasomal activity. Lentiviral-mediated delivery of Nup153 in the hippocampal niche of AD mice increased the proliferation of early progenitors, marked by BrdU/DCX and BrdU/PSANCAM positivity and, later, the integration of differentiating neurons in the cell granule layer (BrdU/NeuN+ cells) compared with GFP-injected AD mice. Consistently, Nup153-injected AD mice showed an improvement of cognitive performance in comparison to AD-GFP mice at 1 month after virus delivery assessed by Morris Water Maze. To validate the role of Nup153 in neurogenesis we took advantage of brain organoids derived from AD-iPSCs characterized by fewer neuroepithelial progenitor loops and reduced differentiation areas. The upregulation of Nup153 in AD organoids recovered the formation of neural-like tubes and differentiation. Conclusions Our data suggest that the positive effect of Nup153 on neurogenesis is based on a complex regulatory network orchestrated by Nup153 and that this protein is a valuable disease target.

Abstract The Russian invasion of Ukraine in 2022 triggered a global wheat price spike and food insecurities in import-dependent countries. We combine an analysis of the global wheat supply network with an agricultural commodity price model to investigate national impaired supplies and the global annual wheat price hike, respectively, for the trade year 2022. Using a scenario analysis, we show that international cooperation manifested in the Black Sea Grain and Solidarity Lanes initiatives and the removal of export restrictions may have mitigated the 2022 price hike by 13 percentage points. In a worst case scenario – characterized by multi-breadbasket harvest failures, escalating export restrictions, and blocked Ukrainian exports – wheat price increases by 90% compared to the 2000–2020 average. Coping strategies – such as food-secure countries dispersing stocks, reducing wheat as feed, or boosting wheat production – are effective at mitigating the price spike in simplified scenarios. Our findings underscore the imperative of coordinated policy responses to avoid global food supply disruptions.

Abstract Herbivorous insects alter biogeochemical cycling within forests, but the magnitude of these impacts, their global variation, and drivers of this variation remain poorly understood. To address this knowledge gap and help improve biogeochemical models, we established a global network of 74 plots within 40 mature, undisturbed broadleaved forests. We analyzed freshly senesced and green leaves for carbon, nitrogen, phosphorus and silica concentrations, foliar production and herbivory, and stand-level nutrient fluxes. We show more nutrient release by insect herbivores at non-outbreak levels in tropical forests than temperate and boreal forests, that these fluxes increase strongly with mean annual temperature, and that they exceed atmospheric deposition inputs in some localities. Thus, background levels of insect herbivory are sufficiently large to both alter ecosystem element cycling and influence terrestrial carbon cycling. Further, climate can affect interactions between natural populations of plants and herbivores with important consequences for global biogeochemical cycles across broadleaved forests.

Abstract Miombo woodlands are integral to livelihoods across southern Africa, biodiversity in the region, and the global carbon cycle, making accurate and precise monitoring of their state and change essential. Here, we assembled a terrestrial and airborne lidar dataset covering 50 kha of intact and degraded miombo woodlands, and generated aboveground biomass estimates with low uncertainty via direct 3D measurements of forest structure. We found 1.71 ± 0.09 TgC was stored in aboveground biomass across this landscape, between 1.5 and 2.2 times more than the 0.79–1.14 TgC estimated by conventional methods. This difference is in part owing to the systematic underestimation of large trees by allometry. If these results were extrapolated across Africa’s miombo woodlands, their carbon stock would potentially require an upward revision of approximately 3.7 PgC, implying we currently underestimate their carbon sequestration and emissions potential, and disincentivise their protection and restoration.

Heritage bridges constitute an integral feature of the urban landscape in numerous cities. However, it is common for these structures to surpass their life cycle, rendering them ill-equipped to withstand the dynamic demands of users and extreme events, particularly hydrological occurrences. This research presents a methodology for the assessment of heritage riverine bridges, with a focus on the Grau Bridge in Peru as a case study. The investigation commences with an exhaustive literature review, complemented by a historical examination, followed by a preliminary diagnosis. Subsequently, hydrological and hydraulic studies are presented, encompassing drone surveys of the riverbed and the bridge, soil analyses, and the application of 1D and 2D models in HEC-RAS. The outcomes of this comprehensive analysis reveal the high vulnerability of the Grau Bridge. Finally, strategic interventions for its conservation are recommended.

ABSTRACT Extracellular vesicles (EV), key players in cell-to-cell communication, may contribute to disease propagation in several neurodegenerative diseases, including Alzheimer’s disease (AD), by favoring the dissemination of neurotoxic proteins within the brain. Interestingly, growing evidence supports the role of herpes simplex virus type 1 (HSV-1) infection in the pathogenesis of AD. Here, we investigated whether HSV-1 infection could promote the spread of phosphorylated tau (ptau) among neurons via EV. We analyzed the ptau species that were secreted via EV following HSV-1 infection in neuroblastoma cells and primary neurons, focusing particularly on T205, T181, and T217, the phosphorylation sites mainly associated with AD. Moreover, by overexpressing human tau tagged with GFP (htauGFP), we found that recipient tau knockout (KO) neurons uptook EV that are loaded with HSV-1-induced phtauGFP. Finally, we exploited an in vivo model of acute infection and assessed that cerebral HSV-1 infection promotes the release of ptau via EV in the brain of infected mice. Overall, our data suggest that, following HSV-1 infection, EV play a role in tau spreading within the brain, thus contributing to neurodegeneration.IMPORTANCEHerpes simplex virus type 1 (HSV-1) infection that reaches the brain has been repeatedly linked with the appearance of the pathognomonic markers of Alzheimer’s disease (AD), including accumulation of amyloid beta and hyperphosphorylated tau proteins, and cognitive deficits. AD is a multifactorial neurodegenerative disease representing the most common form of dementia in the elderly, and no cure is currently available, thus prompting additional investigation on potential risk factors and pathological mechanisms. Here, we demonstrate that the virus exploits the extracellular vesicles (EV) to disseminate phosphorylated tau (ptau) among brain cells. Importantly, we provide evidence that the HSV-1-induced EV-bearing ptau can be undertaken by recipient neurons, thus likely contributing to misfolding and aggregation of native tau, as reported for other AD models. Hence, our data highlight a novel mechanism exploited by HSV-1 to propagate tau-related damage in the brain.

Water Distribution Networks are known to lose a consistent percentage of drinkable water due to the presence of leakages. In this paper it is proposed a solution to detect water leaks consisting of: i) a new sensing equipment able to acoustically monitor the external surface of a newly laid underground pipe; ii) a training of several machine learning models able to analyse the data collected by the new sensing equipment; iii) a user dashboard to give the final user the possibility to monitor the pipe’s condition. The research process included the generation of artificial leakages capable to produce a suitable dataset necessary to properly train machine learning models onto.

Abstract Recombinant multiepitope proteins (RMPs) are a promising alternative for application in diagnostic tests and, given their wide application in the most diverse diseases, this review article aims to survey the use of these antigens for diagnosis, as well as discuss the main points surrounding these antigens. RMPs usually consisting of linear, immunodominant, and phylogenetically conserved epitopes, has been applied in the experimental diagnosis of various human and animal diseases, such as leishmaniasis, brucellosis, cysticercosis, Chagas disease, hepatitis, leptospirosis, leprosy, filariasis, schistosomiasis, dengue, and COVID-19. The synthetic genes for these epitopes are joined to code a single RMP, either with spacers or fused, with different biochemical properties. The epitopes’ high density within the RMPs contributes to a high degree of sensitivity and specificity. The RMPs can also sidestep the need for multiple peptide synthesis or multiple recombinant proteins, reducing costs and enhancing the standardization conditions for immunoassays. Methods such as bioinformatics and circular dichroism have been widely applied in the development of new RMPs, helping to guide their construction and better understand their structure. Several RMPs have been expressed, mainly using the Escherichia coli expression system, highlighting the importance of these cells in the biotechnological field. In fact, technological advances in this area, offering a wide range of different strains to be used, make these cells the most widely used expression platform. RMPs have been experimentally used to diagnose a broad range of illnesses in the laboratory, suggesting they could also be useful for accurate diagnoses commercially. On this point, the RMP method offers a tempting substitute for the production of promising antigens used to assemble commercial diagnostic kits.

Hailstorms, while fascinating from a meteorological perspective, pose significant risks to communities, agriculture, and infrastructure. In regions such as the Central Andes of Peru, the characteristics and frequency of these extreme weather events remain largely uncharted. This study fills this gap by investigating the historical frequency and vertical structure of hailstorms in this region. We analyzed historical hailstorm records dating back to 1958 alongside 4 years of observations (2017–2021) from the Parsivel2 disdrometer and a cloud-profiling radar MIRA35c. Our findings indicate a trend of decreasing hail frequency (−0.5 events per decade). However, the p value of 0.07 suggests the need for further investigation, particularly in relation to environmental changes and reporting methods. The results show that hailstorms predominantly occur during the austral summer months, with peak frequency in December, and are most common during the afternoon and early evening hours. The analysis of radar variables such as reflectivity, radial velocity, spectral width, and linear depolarization ratio (LDR) reveals distinct vertical profiles for hail events. Two case studies highlight the diversity in the radar measurements of hailstorms, underscoring the complexity of accurate hail detection. This study suggests the need for refining the Parsivel2 algorithm and further understanding its classification of hydrometeors. Additionally, the limitations of conventional radar variables for hail detection are discussed, recommending the use of LDR and Doppler spectrum analysis for future research. Our findings lay the groundwork for the development of more efficient hail detection algorithms and improved understanding of hailstorms in the Central Andes of Peru.

Abstract Methylmalonic acidemia cblB type (MMA cblB) is an autosomal recessive inborn error of amino acid metabolism that results in impaired synthesis of adenosylcobalamin, a cofactor of methylmalonyl‐CoA mutase. It presents with episodes of coma, vomiting, hypotonia, metabolic acidosis, and hyperammonemia. End‐stage kidney disease is a long‐term complication. Treatments include vitamin B12 supplementation, L‐carnitine, and a low‐protein diet. Liver, kidney, or combined liver‐kidney transplantations are promising options, but they are not without complications. We report a patient suffering from MMA cblB who developed end‐stage kidney disease at 18 years of age. Kidney transplantation allowed him to recover normal kidney function and good metabolic control. Unfortunately, after two decades, he developed non‐Hodgkin lymphoma and severe chemotherapy toxicity which led to his death. The risk of lymphoproliferative diseases is known to increase after solid organ transplantation. However, in MMA, factors including mitochondrial dysfunction and oncometabolites, may further increase the risk of malignancy and drug toxicity. Our report highlights the importance of considering the increased risk of cancer in long‐term follow‐up of MMA cblB patients, especially after solid organ transplantation. Moreover, when chemotherapy is needed, the increased risk of toxicity and metabolic decompensation should be considered and monitored.

Background Chagas disease (CD) is a neglected tropical disease endemic to Latin America, has emerged as a global health concern due to the migration of infected individuals. With its epidemiological complexity, by difficulty to obtain appropriate diagnoses and poor treatment, the search for novel therapeutic options remains. Methods In this context, we conducted a systematic review and meta-analysis of preclinical studies employing animal models to verify the progress in CD treatment. We searched the PubMed database for CD treatment studies published between 1990 and 2023, adhering to the PRISMA guidelines. Results Twelve papers met the inclusion criteria. The findings indicate that the fifteen treatment alternatives examined, mainly between 2010 and 2014, demonstrated efficacy in experimental CD models, evidenced by significant parasitemia reduction. Bis-triazole DO870 and VNI were effective in the acute and chronic phases, respectively. However, of these emerging therapies, only posaconazole and fexinidazole have progressed to clinical trials, yielding unsatisfactory outcomes as CD monotherapies Conclusions This meta-analysis highlights the existence of promising new drug candidates for CD treatment, but most remain in the preclinical stages. Those that reached clinical trials did not demonstrate optimal results, underscoring the ongoing challenges in CD therapy. Collaborative efforts among the academic community, pharmaceutical industries, funding agencies, and government agencies are urgently needed to accelerate the development of more effective medications against CD. Inplasy registration INPLASY202430101 (25/03/2024)

The present study aimed to extract polyphenolic compounds from lucuma (Pouteria lucuma) seeds using natural deep eutectic solvents (NADES) as a green, efficient, and environmentally friendly extraction. This was optimized by using the Response Surface Method (RSM) and comparing its predictive capacity with Artificial Neural Networks (ANN) and Convolutional Neural Networks (CNN). Four NADES were prepared by mixing lactic acid (LA) with each of the following reagents: sodium acetate (SA), urea (U), glucose (G), and ammonium acetate (AA), separately. The yield of total phenolic compounds (TPC) obtained from lucuma seeds with each NADES was measured as an optimization criterion with the Box-Benhken design. The following factors were evaluated: time, temperature, and the lucuma seed flour (LSF): NADES ratio. The response variables were TPC and antioxidant activity. The LA-AA extract was selected because it exhibited the highest TPC value and was analyzed by UHPLC–MS (Ultra-performance Liquid Chromatography-Mass Spectrometry). From the RSM, the optimal extraction parameters were 80 min, 52°C, and LSF: NADES ratio of 8:100 (w/v), obtaining a TPC value of 3601.51 ± 0.51 mg GAE/100 g LFS. UHPLC–MS analysis evidenced the formation of epigallocatechin isomers from epigallocatechin gallate. The predictive ability of ANNs compared to RSM was demonstrated.

Abstract To date, little is known about the usefulness of ultra-high frequency ultrasound (UHF-US, 50–70 MHz) in clinical practice for the diagnosis of dysimmune neuropathies. We present a prospective study aimed at comparing UHF-US alterations of nerves and fascicles in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), distal CIDP (d-CIDP) and anti-MAG neuropathy and their relationships with clinical and electrodiagnostic (EDX) features. 28 patients were included (twelve CIDP, 6 d-CIDP and 10 anti-MAG) and ten healthy controls. Each patient underwent neurological examination, EDX and UHF-US study of median and ulnar nerves bilaterally. UHF-US was reliable in differentiating immune neuropathies from controls when using mean and/or segmental nerve and/or fascicle cross-sectional area (CSA); furthermore, fascicle ratio (fascicle/nerve CSA) was a reliable factor for differentiating d-CIDP from other types of polyneuropathies. The fascicle CSA appears to be more increased in CIDP and its variant than in anti-MAG neuropathy. UHF-US offers information beyond simple nerve CSA and allows for a better characterization of the different forms of dysimmune neuropathies.

The continuous expansion of the vehicle fleet contributes to escalating emissions, with the transportation sector accounting for approximately 21% of CO2 emissions, based on 2023 data. Focused on reducing emissions and reliance on fossil fuels, the study observes the shift from internal combustion vehicles to electric and hybrid models since 2017. Despite advancements, these vehicles still lack optimal efficiency and suffer from limited range, deterring potential buyers. This article aims to evaluate the range-extending technologies for electric vehicles, emphasizing efficiency, low pollution, and integration compatibility. An algorithm incorporating equations representing mechanical or electrical component curves is developed for Extended-Range Electric Vehicles, facilitating insight into potential range extender behavior. The core objectives of this study involve optimizing the entire powertrain system to ensure peak efficiency. Experimental tests demonstrate that integrating an auxiliary power unit enhances range, with an internal combustion engine generator configuration extending the travel distance by 35.35% at a constant speed. Moreover, with the use of an Equivalent Consumption Minimization Strategy control, the distance traveled increases up to 39.28% on standard driving cycles. The proposed methodology, validated through practical implementations, allows for comprehensive energy analyses, providing a precise understanding of vehicle platform performance with integrated range extenders.