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Summertime weather stress indices for Phoenix, Arizona are analysed for the period 1948 to 1984. Weather stress levels for the nighttime period are increasing rapidly over the past several decades. These increasing discomfort levels are a result of a sharp increase in nocturnal temperatures. A small, but statistically significant, decline in atmospheric moisture levels is moderating the upward trend in weather stress. Changes in local land-use patterns are apparently responsible for the general trends found in the temperature, atmospheric moisture, and weather stress indices. Es werden Indizes des sommerlichen Wetterstreß für den Zeitraum 1948 bis 1984 analysiert. Die nächtlichen Komfortwerte haben sich in den vergangenen Jahrzehnten rasch verschlechtert, verursacht von einer deutlichen Erhöhung der Nachttemperaturen. Eine geringe, aber statistisch signifikante Verringerung der Luftfeuchtigkeit verlangsamt den Aufwärtstrend des Wetterstreß. Für diese Entwicklungen der Temperatur, Feuchte und Behaglichkeitsindizes sind offenbar die Veränderungen der lokalen Landnutzung verantwortlich. [ABSTRACT FROM AUTHOR]

Waterlogging causes various metabolic, physiological, and morphological changes in crops, resulting in yield loss of most legumes in rainfed and irrigated agriculture. However, research on cowpea genotypes using physiological and biochemical traits as a measure of tolerance to waterlogging stress is limited. We evaluated the impacts of 7 days of waterlogging (DOW) and 7 days of recovery (DOR) on the physiology and biochemistry of two cowpea (Vigna unguiculata (L.) Walp) genotypes (UCR 369 and EpicSelect.4) with contrasting waterlogging tolerance. Cowpea genotypes were grown in a controlled environment until the R2 stage and then subjected to 7 DOW. Later, the waterlogged plants were reoxygenated for an additional 7 DOR. Overall, cowpea genotypes had a contrasting response to waterlogging using different mechanisms. Compared to the control, the photosynthetic parameters of both cowpea genotypes were impaired under 7 DOW and could not recover at 7 DOR, with a larger decline in EpicSelect.4.7 DOW caused significant loss in the chlorophyll and carotenoid content of both genotypes. However, only waterlogged UCR 369 was not photo-inhibited and able to restore the levels of chlorophyll and carotenoids at 7 DOR. In addition, 7 DOW induced intense stress in UCR 369 with increased zeaxanthin, sucrose, and flavonoid content, while these metabolites were decreased in EpicSelect.4. On the other hand, glucose, fructose, and phenolic content were increased in EpicSelect.4 but decreased in UCR 369 at 7 DOR. In summary, compared to EpicSelect.4, UCR 369 restored their photosynthetic pigments and metabolites to the control levels at 7 DOR, indicating a likely tolerance to waterlogging stress., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier Masson SAS.)

Due to climate change, the attainment of global food security is facing serious challenges in meeting the growing food demand. Abiotic stresses are the foremost limiting factors for agricultural productivity. However, not much information is available on the effect of multiple abiotic stresses on the morphological and biochemical aspects of kale and mustard. Therefore, an experiment was designed to study the effects of UV-B radiation, CO 2 concentration, and high temperature on the growth, yield, and biochemistry of two Brassica species, namely B. oleracea L. var. acephala Winterbor F1 (hybrid kale) and B. juncea var. Green wave O.G. (mustard greens), which were grown under optimal nutrients and soil moisture conditions in soil-plant-atmosphere-research (SPAR) units. Two levels of UV-B radiation (0 and 10 kJ m -2 d -1 ), two concentrations of CO 2 (420 and 720 ppm), and two different temperature treatments (25/17 °C and 35/27 °C) were imposed 12 days after sowing (DAS). Several morphological and biochemical parameters were measured at harvest (40 DAS) in both species. All the traits declined considerably under individual and multi-stress conditions in both species except under elevated CO 2 levels, which had a positive impact. Marketable fresh weight decreased by 64% and 58% in kale and mustard plants, respectively, growing under UV-B treatment. A slight increase in the chlorophyll content was observed in both species under the UV-B treatment alone and in combination with high temperature and elevated CO 2 . Understanding the impacts of high temperature, CO 2 , and UV-B radiation treatments on leafy vegetables, such as kale and mustard, can help to improve existing varieties to enhance resilience towards environmental stresses while simultaneously improving yield, morphology, and biochemistry in plants.

Waterlogging is an important environmental stress limiting the productivity of crops worldwide. Cowpea ( Vigna unguiculata L.) is particularly sensitive to waterlogging stress during the reproductive stage, with a consequent decline in pod formation and yield. However, little is known about the critical processes underlying cowpea's responses to waterlogging during the reproductive stage. Thus, we investigated the key parameters influencing carbon fixation, including stomatal conductance (g s ), intercellular CO 2 concentration, chlorophyll content, and chlorophyll fluorescence, of two cowpea genotypes with contrasting waterlogging tolerance. These closely related genotypes have starkly contrasting responses to waterlogging during and after 7 days of waterlogging stress (DOW). In the intolerant genotype ('EpicSelect.4'), waterlogging resulted in a gradual loss of pigment and decreased photosynthetic capacity as a consequent decline in shoot biomass. On the other hand, the waterlogging-tolerant genotype ('UCR 369') maintained CO 2 assimilation rate ( A ), stomatal conductance (g s ), biomass, and chlorophyll content until 5 DOW. Moreover, there was a highly specific downregulation of the mesophyll conductance (g m ), maximum rate of Rubisco (V cmax ), and photosynthetic electron transport rate (J max ) as non-stomatal limiting factors decreasing A in EpicSelect.4. Exposure of EpicSelect.4 to 2 DOW resulted in the loss of PSII photochemistry by downregulating the PSII quantum yield (F v /F m ), photochemical efficiency (Φ PSII ), and photochemical quenching (qP). In contrast, we found no substantial change in the photosynthesis and chlorophyll fluorescence of UCR 369 in the first 5 DOW. Instead, UCR 369 maintained biomass accumulation, chlorophyll content, and Rubisco activity, enabling the genotype to maintain nutrient absorption and photosynthesis during the early period of waterlogging. However, compared to the control, both cowpea genotypes could not fully recover their photosynthetic capacity after 7 DOW, with a more significant decline in EpicSelect.4. Overall, our findings suggest that the tolerant UCR 369 genotype maintains higher photosynthesis under waterlogging stress attributable to higher photochemical efficiency, Rubisco activity, and less stomatal restriction. After recovery, the incomplete recovery of A can be attributed to the reduced g s caused by severe waterlogging damage in both genotypes. Thus, promoting the rapid recovery of stomata from waterlogging stress may be crucial for the complete restoration of carbon fixation in cowpeas during the reproductive stage.

Waterlogging induces growth and developmental changes in sensitive crops such as cucumber ( Cucumis sativus L.) during early plant development. However, information on the physiological mechanisms underpinning the response of cucumber plants to waterlogging conditions is limited. Here, we investigated the effects of 10-day waterlogging stress on the morphology, photosynthesis, and chlorophyll fluorescence parameters in two cultivars of cucumber seedlings. Waterlogging stress hampered cultivars' growth, biomass accumulation, and photosynthetic capacity. Both cultivars also developed adventitious roots (ARs) after 10 days of waterlogging (DOW). We observed differential responses in the light- and carbon-dependent reactions of photosynthesis, with an increase in light-dependent reactions. At the same time, carbon assimilation was considerably inhibited by waterlogging. Specifically, the CO 2 assimilation rate ( A ) in leaves was significantly reduced and was caused by a corresponding decrease in stomatal conductance (g s ). The downregulation of the maximum rate of Rubisco efficiency (V cmax ) and the maximum rate of photosynthetic electron transport (J max ) were non-stomatal limiting factors contributing to A reduction. Exposure of cucumber to 10 DOW affected the PSII photochemistry by downregulating the PSII quantum yield (Φ PSII ). The redox state of the primary quinone acceptor in the lake model (1-qL), a measure of the regulatory balance of the light reactions, became more oxidized after 10 DOW, indicating enhanced electron sink capacity despite a reduced A . Overall, the results suggest that waterlogging induces alterations in the photochemical apparatus efficiency of cucumber. Thus, developing cultivars that resist inhibition of PSII photochemistry while maintaining carbon metabolism is a potential approach for increasing crops' tolerance to waterlogged environments., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Olorunwa, Adhikari, Brazel, Popescu, Popescu and Barickman.)

Background: Multidisciplinary heart failure (HF) programs reduce hospital readmission and improve clinical outcomes. Although dietitians are often members of such teams, no randomized studies have demonstrated the independent benefit of dietitian-administered dietary counseling for patients with HF. The purpose of this study was to evaluate the effect of dietitian education on adherence to a sodium-restricted diet in ambulatory patients with stable HF., Methods: Patients with HF (left ventricular ejection fraction < 35%) were randomized into a dietitian education group (n = 23) or a usual care group (n = 24), then observed for 3 months. Both groups received a 2 g/d dietary sodium prescription. The usual care group received nutrition advice by way of self-help literature, whereas the dietitian education group returned for 2 counseling sessions with a dietitian., Results: Dietitian education resulted in a significant decrease in sodium intake at 3 months (2.80 +/- 0.30 to 2.14 +/- 0.23 g/d, P < .05). In contrast, there was no change in sodium intake in the usual care group (3.00 +/- 0.31 to 2.74 +/- 0.35 g/d, P = ns)., Conclusions: Dietitian-administered counseling was more effective than providing literature in reducing dietary sodium intake in patients with stable HF.

Sixty-one women with newly diagnosed locoregional breast cancer (T1-3, N0-1, M0) having an initial Body Mass Index (BMI) between 20 and 35 kg/m2 who were receiving standard adjuvant treatment (chemotherapy, tamoxifen, and/or radiation) were asked to avoid weight gain (if initial BMI < or = 25 kg/m2) or to lose up to 10 kg (if initial BMI 25-35 kg/m2) over one year. Women participated in twenty group sessions (10 weekly, 10 monthly) which involved a psychological supportive-expressive group intervention supplemented by individual weight goals, and nutrition and exercise programs. Fifty-five non-censored women (5 developed recurrence, 1 died of a subarachnoid hemorrhage) lost a mean of 0.53 +/- 3.72 kg. Weight loss was greatest in initially overweight women (BMI > or = 25 kg/m2) who lost 1.63 +/- 4.11 kg (p = 0.01 compared to normal weight women) and in those not receiving chemotherapy who lost 2.15 +/- 2.83 kg (p = 0.0004 compared to those receiving chemotherapy). 70.9% met predefined criteria for success. Aerobic exercise increased significantly during the intervention (p = 0.00005) and was the strongest predictor of success (OR 1.73 for each additional 30 minutes of exercise weekly, p = 0.003). Changes in caloric intake were not significant, but fat intake decreased and carbohydrate and fibre intake increased significantly during the intervention. Eating behavior and psychological status improved significantly. Thus, this multidisciplinary weight management intervention successfully prevented weight gain in women with newly diagnosed locoregional breast cancer, and helped overweight women lose weight.

Purpose: To present the ocular pathology of a three-year-old child with Leber's congenital amaurosis (LCA) who died from an unrelated episode of presumed viral meningitis., Methods: Autopsy was performed, and in addition the globes were harvested for pathological examination. Before the child's death, known systemic disorders with infantile retinal dystrophy were excluded., Results: The outer nuclear layer and photoreceptor layers are the primary site of retinal pathology in LCA., Conclusion: This report of the pathological findings in LCA, early in the natural history of the disease, indicates that process appears to be a degeneration rather than an agenesis.

A 6-month-old female infant with biopsy-proved Hirschsprung's disease had associated sector heterochromia of the irides. The association between sector heterochromia and Hirschsprung's disease has been previously reported and both conditions have been ascribed to neural crest defects. Histologic characteristics of the ocular involvement have not previously been reported, to our knowledge. Histopathologic examination of the globes revealed decreased iris stroma, decreased pigmentation in the anterior stroma, and reduced numbers of pigment-producing cells in the affected areas. Both the ocular and gastrointestinal findings reflect abnormalities in tissues of neural crest origin.