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Grain yield and the stability of harvest index are greater in newer than in older Argentinean maize (Zea muys L.) hybrids. The objective of this study was to elucidate mechanisms underlying the superior yield and harvest index stability of newer Argentinean maize hybrids using the relationship between kernel number per plant (K[N.sub.P]) and plant growth rate during the period bracketing silking (PG[R.sub.S]). Three experiments were performed at Balcarce, Argentina, during two growing seasons (1998-2000). Maize was grown under a wide range of plant densities (from 2 up to 30 plants [m.sup.-2]) to generate contrasting availability of resources per plant. Growth of individual plants during the period bracketing silking was estimated through a nondestructive method on the basis of relationships between actual shoot dry matter and morphometric variables, including stem and ear diameters and ear length. Detasseling and silk pollination synchronization treatments were imposed in one experiment to also modify available resources per kernel and kernel sink strength. Newer hybrids set more kernels per unit PG[R.sub.S] than older hybrids as is indicated by (i) the lower threshold PG[R.sub.S] for kernel set and (ii) greater potential kernel number at high availability of resources per plant, for newer than for older hybrids. At low and intermediate PG[R.sub.S], the greater kernel set per unit PG[R.sub.S] in newer vs. older hybrids was attributable to greater partitioning of dry matter to the topmost ear during the period bracketing silking, whereas number of kernels set per unit of ear growth rate did not differ. In contrast, kernel set per unit of ear growth rate was greater in newer than in older hybrids when PG[R.sub.S] was high. Results of this study indicate that genetic yield improvement in maize is attributable, in part, to increased partitioning of dry matter to the ear during the critical period bracketing silking., YIELD OF NEWER ARGENTINEAN MAIZE hybrids is greater than that of older ones (Echarte et al., 2000). Genetic yield improvement in North American maize hybrids has been associated with increased [...]

Final kernel number in maize (Zea mays L.) is closely associated with the physiological condition of the crop during the critical period bracketing silking. The objective of this study was to determine whether there is a common underlying relationship between kernel number per plant (KNP) and plant growth rate (PGR) during that critical period when plant growth varies because of different abiotic stresses. A relationship between KNP and PGR obtained from a previous study of variation in plant density and incident radiation was used as reference. KNP and PGR were measured in experiments in which incident radiation per plant, nitrogen (N), and water availabilities were the experimental sources of variation. The equation fitted to the data obtained at different radiation levels explained 72% of the variation in the data obtained at different levels of N or water availability. Moreover, different models for each set of data did not provide a significantly better fit than a single model for the two sets of data combined. A common relationship between KNP and PGR was also obtained when N supply and water availability were variable. The relationship between KNP and PGR obtained for treatments in which PGR was varied through plant density and shading also could predict KNP for conditions in which PGR was affected by water and/ or N deficiencies. The PGR during the critical period of kernel set is a good predictor of the capacity of the maize plant to set kernels under a wide range of environmental and management practices., MAIZE GRAIN YIELD is closely associated with kernel number at harvest and this yield component is a function of the physiological condition of the crop during the period bracketing flowering [...]

The Pampa comprises the most productive land in Argentina, but the widespread adoption of sole cropping has drastically reduced soil organic carbon (SOC) stocks. This paper presents baseline data on the effects of maize-legume inter-crops compared with maize and soyabean sole crops on SOC and nitrogen (N) stocks, gross SOC turnover, soil microbial biomass (SMB), soil organic matter light fraction (LF) and the partitioning of carbon (C) derived from C- and C crops into SOC, LF and SMB. For soil characteristics, only the C:N ratio was significantly different (0-120 cm) between treatments. Gross SOC and SMB-C turnover time (0-120 cm) was faster in the maize sole crop followed by the inter-crops and the soyabean sole crop. The SMB-C and N were significantly greater in the intercrops. Soil LF-N (0-20 cm) was significantly smaller in the inter-crop. Soil became significantly enriched (0-120 cm) in δN in the inter-crop, suggesting that microbial decomposers incorporated C derived from maize and soyabean residues. The greatest proportion of C in the soil and in the soil LF was derived from a C-C source, and the δC of the SMB (0-20 cm) was enriched compared with that of the SOC and the soil LF. Results from this study indicated that after only 1 year of inter-cropping, soil biological and chemical characteristics were influenced positively by this land management practice. [ABSTRACT FROM AUTHOR]

Background: During the most critical phases of COVID-19 pandemic, dramatic situations were experienced in hospitals and care centers that nurses could hardly verbalize. Especially relevant were deep challenges related to terminal illness, situations of extreme sacrifice, as well as reflections on protective measures mixed with beliefs. We intend to analyze which problems had the greatest impact on professionals., Aim: The aim is to explore the ultimate basis for action when making decisions and the orientation of their behavior in the face of moral conflicts., Method: The methodological strategy is an interpretive synthesis. Narrative review of academic articles that analyzed ethical dilemmas during the pandemic was carried out by searching five databases (Pubmed, Scopus, Psycinfo, CINHAL, and WOS) between January 2020 and December 2022. Finally, 43 articles were selected., Ethical Considerations: Ethical requirements were respected in all study phases., Results: The reading and review of the 43 articles initiated the first phase of inductive coding which resulted in 14 initial sub-themes. Based on this structure, a second phase of coding was carried out, giving rise to six categories or emerging themes. To facilitate the process of identifying the central category, the authors agreed to carry out a phase of synthesis, grouping the six themes into three meta-themes: the identification and acceptance of human vulnerability; the discovery of positive paradigms in traumatic situations in society; the prevalence of the common good over the particular interest, as the core structure of any society., Conclusion: The study has shown the need to consider healthcare benevolence as a new dimension of health care upon global vulnerability. Responsibility is required to ensure the well-being of a global society, prioritizing the common good over particular interests and building solutions on solid moral structures. A new ethical landscape is essential, starting with a humanistic curricular training of all healthcare professionals.

Adequate management of N supply, plant density, row spacing, and soil cover has proved useful for increasing grain yields and/or grain yield stability of rainfed crops over the years. We review the impact of these management practices on grain yield water-related determinants: seasonal crop evapotranspiration (ET) and water use efficiency for grain production per unit of evapotranspired water during the growing season (WUEG,ET,s). We highlight a large number of conflicting results for the impact of management on ET and expose the complexity of the ET response to environmental factors. We analyse the influence of management practices on WUEG,ET,s in terms of the three main processes controlling it: (i) the proportion of transpiration in ET (T/ET), (ii) transpiration efficiency for shoot biomass production (TEB), and (iii) the harvest index. We directly relate the impact of management practices on T/ET to their effect on crop light interception and provide evidence that management practices significantly influence TEB. To optimize WUEG,ET,s, management practices should favor soil water availability during critical periods for seed set, thereby improving the harvest index. The need to improve the performance of existing crop growth models for the prediction of water-related grain yield determinants under different management practices is also discussed., (© The Author(s) 2023. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Background: The use of a deceased donor (DD) as an alternative source of human mesenchymal stromal cells (hMSC) is promising, but has been little explored. This study evaluated the potential of femur bone marrow (FBM) from brain-death donors as a source of hMSC and compared this with hMSC from matched iliac crest bone marrow (ICBM)., Methods: Sixteen donor-matched FBM and ICBM samples were processed from brain-death donors. We analyzed the starting material and compared cell yield, phenotypic profile and differentiation capacity of hMSC., Results: Neither the amount of nucleated cells per gram (14.6×10 6 ±10.3×10 6 from FBM vs. 38.8×10 6 ±34.6×10 6 from ICBM, P≥0.09) nor the frequency of CFU-F (0.0042%±0.0036% in FBM vs. 0.0057%±0.0042% in ICBM, P≥0.73) differ significantly from FBM or ICBM. Cell cultures from both sources were obtained and hMSC yields showed that there were no significant differences in hMSC obtained per gram of bone marrow (BM) when comparing femur with iliac crest samples. At passage 2, 12.5×10 6 ±12.9×10 6 and 5.0×10 6 ±4.4×10 6 hMSC per gram of BM were obtained from FBM and ICBM, respectively. FBM and ICBM hMSC express CD73, CD90, CD105, but not hematopoietic lineage markers [CD45, CD34, CD11, CD19 and isotype of HLA clase II (HLA-DR)]. HLA-A expression from both sources was clearly detected, while HLA-B was weakly expressed or undetectable and HLA-DR was undetectable. Cells from both sources were differentiated in vitro into osteoblasts, adipocytes and chondroblasts., Conclusions: To our knowledge, there are no previous studies evaluating BM from femur dead donors as a source of hMSC. Our findings confirm that it is feasible to expand cells from FBM from brain-death donors meeting in vitro characteristics of hMSC, making them a promising source for clinical translation., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://sci.amegroups.com/article/view/10.21037/sci-2023-003/coif). The authors have no conflicts of interest to declare., (2023 Stem Cell Investigation. All rights reserved.)

Introduction: Myelodysplastic syndromes (MDS) are a heterogeneous group of clonal hematological diseases. In addition to defects in hematologic progenitor and stem cells, dysfunctions in the bone marrow microenvironment (BMM) participate in the MDS pathogenesis. Furthermore, the immune response is deregulated by the pro-inflammatory response prevailing in low-risk MDS, while immunosuppression predominates in high-risk MDS. Mesenchymal stromal cells (MSC), part of the BMM, are characterized by plastic adherent growth and multipotentiality. They exhibit immunomodulatory properties and sustain hematopoiesis. There is conflicting evidence regarding their status in MDS. The aim of this study was to characterize MDS-MSC and evaluate the effect of 5-Azacytidine., Methods: The MSC from MDS patients and controls were cultured and characterized according to the International Society of Cell Therapy recommendations. Immunomodulatory properties were assessed by studying the MSD cytokine production, using the cytometric bead array. We evaluated the effect of 5-Azacytidine on the MSC cytokine production., Results: We included 35 MDS patients and 22 controls. The MSC from patients and controls were cultured and characterized. The MSC from patients showed morphological differences, but there were no differences in immunophenotype or multipotentiality. The interleukin 6 (IL-6) was the main MSC secreted cytokine. The MDS-MSC produced higher levels of IL-6, IL-17, interferon gamma, or interferon γ (INF-γ), and tumor necrosis factor alpha (TNF-α). The in vitro 5-Azacytidine treatment induced a significant decrease in the IL-6 production by MDS-MSC., Conclusions: The MDS-MSC show an increased production of pro-inflammatory cytokines. The in vitro treatment with 5-Azacytidine lead to a significant reduction in the IL-6 production by the MDS-MSC, restoring the IL-6 levels to those found in controls. The MSC produced inflammatory cytokines involved in the MDS pathogenesis, representing a potential future therapeutic target. Moreover, 5-Azacytidine may have a stromal effect, modulating the immune response in MDS., (Copyright © 2020 Associação Brasileira de Hematologia, Hemoterapia e Terapia Celular. Published by Elsevier Editora Ltda. All rights reserved.)

Ultrapotent topical corticosteroids and circumcision are usually effective for male genital lichen sclerosus (MGLSc); however, refractory cases are often referred to our Male Genital Dermatology Unit. Treatment with autologous platelet-rich plasma (TPRP) has recently been advocated as a safe and effective treatment option, but there have been no prospective studies in men to date. The objective of this study is to assess the safety and efficacy of TPRP for MGLSc resistant to conventional therapy. A prospective, open-label, single-arm, therapeutic study was carried out in this study. Inclusion criteria: resistant to conventional therapy for at least 6 months. Procedure: infiltration of 0.1 mL/cm 2 PRP every 8 weeks. Monthly data recording: visual appearance with photographs and external scoring by an expert using Investigator's Global Assessment Scale (IGA scale 0-5), symptoms (scale 0-5), quality of life (QoL; Dermatology Life Quality Index [DLQI]), and complications. No. of patients included was n = 5. No. of patients excluded during treatment was n = 1. Mean initial IGA: 3.6. Mean initial DLQI: 6. TPRP n = 34 (range: 2-9; average: 6.8 per patient). Mean IGA at 18 months: 3.25. Mean DLQI at 18 months: 1.25. All patients reported being completely asymptomatic at 10 months. No. of patients with complications is n = 1 (balanitis). TPRP seems to be safe and effective, regarding symptom control and improvement in QoL; however, visual changes were minimal., (© 2020 Wiley Periodicals LLC.)

Background: Chronic venous leg ulcers (VLUs) are a common problem in clinical practice and available treatments are not satisfactory. The use of adjuvant therapies in combination with lower limb compression may lead to improved healing rates. Chronic wounds are candidates for new strategies in the emergent field of regenerative medicine. Bone marrow-derived cells (BMDCs) contain cells and secrete cytokines known to participate in wound healing. Thus, BMDC therapy seems a logical strategy for the treatment of chronic wounds. Our objective was to evaluate feasibility, safety and initial clinical outcome of autologous BMDC therapy associated with standard treatment in patients with VLUs., Methods: We conducted an open-label, single-arm, prospective pilot clinical trial in four patients with six chronic VLUs. The study protocol was approved by the institutional and national review boards and ethics committees. Bone marrow was harvest, processed and then administered by multiple injections into the ulcers. All patients received standard treatment and non-healing characteristics of the VLUs were confirmed at study entry., Results: Ulcer size and wound pain evaluated 12 months after BMDC treatment were significantly reduced (P < 0.05). BMDC treatment was safe and well tolerated in long-term follow-up., Discussion: Despite the low number of patients studied, our results showed that autologous BMDC treatment could be a useful, feasible and safe procedure to enhance ulcer healing. However, randomized controlled trials with more patients are needed to address this question and translate this approach into clinical practice., (Copyright © 2019 International Society for Cell and Gene Therapy. Published by Elsevier Inc. All rights reserved.)

Numerous studies show that personal spirituality developed through prayer positively influences mental health. Phenomenological and neuroscientific studies of mindfulness, an Eastern meditative prayer form, reveal significant health benefits now yielding important insights useful for guiding treatment of psychological disorders. By contrast, and despite its practice for millennia, Christian meditation is largely unrepresented in studies of clinical efficacy. Resemblances between mindfulness and disciplinary acts in Christian meditation taken from the ancient Greek practice of askesis suggest that Christian meditation will prove similarly beneficial; furthermore, psychological and neuroscientific studies suggest that its retention of a dialogical and transcendent praxis will additionally benefit social and existential psychotherapy. This paper thus argues that study of contemplative meditation for its therapeutic potential is warranted.

Rationale: Serial smear analysis to guide respiratory isolation (RI) of patients with suspected tuberculosis (TB), the majority of whom will be found not to have TB, leads to expensive and unnecessary isolation, and may potentially result in decreased vigilance of subjects with respiratory compromise., Objectives: To compare the performance of a single first-sputum, Mycobacterium tuberculosis-specific nucleic acid amplification (NAA) test with three sputum smears for assessing the need for RI., Methods: Prospective evaluation of 493 patients with suspected TB (74% HIV positive) admitted to RI in a major county hospital in the United States, who had at least three sputum smears and material available from the first sample for additional NAA testing., Measurements and Main Results: Accuracy of the first sputum NAA result and serial smears for identifying patients with potentially infectious TB who truly require RI was determined. Forty-six patients (9.3%) had TB confirmed by culture. First-sputum NAA test detected all patients with TB who had a positive smear (n = 35), even when the first of the three specimens was smear negative. In addition, when compared with serial smears, the first-sputum NAA had a higher sensitivity (0.87; 95% confidence interval [CI], 0.74-0.95) and specificity (1.0) in the detection of subjects with positive M. tuberculosis cultures (smear sensitivity, 0.76; 95% CI, 0.61-0.87; and specificity, 0.96; 95% CI, 0.94-0.98)., Conclusions: A single first-sputum NAA testing can rapidly and accurately identify the subset of patients with suspected TB who require RI according to serial sputum smears. Its potential use to shorten RI time does not preclude the need to obtain subsequent specimens for culture.