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In this chapter we provide an overview of campus ecology and ecological systems theory as applied to the study of higher education, most often to research on college students. We describe Bronfenbrenner's developmental ecological model and its application of it to the study of college students. We then discuss affordances and limitations of this approach, including criticism of its lack of attention to systems of privilege and oppression in the higher education environment. We present a number of innovative approaches to using the Bronfenbrenner model that address these limitations, as well as adaptations to the model that incorporate critical theory, queer theory, and Indigenous Knowledge Systems. Practical Takeaways: Ecological systems theory offers a powerful framework for understanding college students and organizational studies in postsecondary education.Despite the utility of ecological models, they fail fully to take into account systemic forces like racism, homophobia, and transphobia that work at every level from the individual to the macro‐level, rendering them less powerful than they could be.Innovative applications of ecological models provide new insights into higher education.Researchers have developed new adaptations of ecological models that incorporate critical lenses (e.g., queer theory, critical race theory, decolonial theory), enabling richer analysis of higher education. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses the articles in the issue on topics including critical approaches to using ecological models in higher education research.

Developed as part of a larger effort by the National Weather Service (NWS) Radar Operations Center to modernize their suite of single-radar severe weather algorithms for the WSR-88D network, the Tornado Probability Algorithm (TORP) and the New Mesocyclone Detection Algorithm (NMDA) were evaluated by operational forecasters during the 2021 National Oceanic and Atmospheric Administration (NOAA) Hazardous Weather Testbed (HWT) Experimental Warning Program Radar Convective Applications experiment. Both TORP and NMDA leverage new products and advances in radar technology to create rotation-based objects that interrogate single-radar data, providing important summary and trend information that aids forecasters in issuing time-critical and potentially life-saving weather products. Utilizing virtual resources like Google Workspace and cloud instances on Amazon Web Services, 18 forecasters from the NOAA/NWS and the U.S. Air Force participated remotely over three weeks during the spring of 2021, providing valuable feedback on the efficacy of the algorithms and their display in an operational warning environment, serving as a critical step in the research-to-operations process for the development of TORP and NMDA. This article will discuss the details of the virtual HWT experiment and the results of each algorithm's evaluation during the testbed. Significance Statement: Before transitioning newly developed radar-based severe weather applications to forecasting operations, an experiment simulating the use of these tools by end users issuing severe weather warnings is helpful to identify both how they are best utilized and address any needed improvements to increase their operational readiness. Conducted in 2021, this study describes the forecaster evaluation of the single-radar Tornado Probability Algorithm (TORP) and the New Mesocyclone Detection Algorithm (NMDA) in one of the first completely virtual Hazardous Weather Testbed (HWT) experiments. Participants stated both TORP and NMDA offered marked improvement over the currently available algorithms by helping the operational forecaster build their confidence when issuing severe weather warnings and increasing their overall situational awareness of storms within their domain. [ABSTRACT FROM AUTHOR]

A new probabilistic tornado detection algorithm was developed to potentially replace the operational tornado detection algorithm (TDA) for the WSR-88D radar network. The tornado probability algorithm (TORP) uses a random forest machine learning technique to estimate a probability of tornado occurrence based on single-radar data, and is trained on 166 145 data points derived from 0.58-tilt radar data and storm reports from 2011 to 2016, of which 10.4% are tornadic. A variety of performance evaluation metrics show a generally good model performance for discriminating between tornadic and nontornadic points. When using a 50% probability threshold to decide whether the model is predicting a tornado or not, the probability of detection and false alarm ratio are 57% and 50%, respectively, showing high skill by several metrics and vastly outperforming the TDA. The model weaknesses include false alarms associated with poor-quality radial velocity data and greatly reduced performance when used in the western United States. Overall, TORP can provide realtime guidance for tornado warning decisions, which can increase forecaster confidence and encourage swift decision-making. It has the ability to condense a multitude of radar data into a concise object-based information readout that can be displayed in visualization software used by the NationalWeather Service, core partners, and researchers. [ABSTRACT FROM AUTHOR]

The local, linear, least squares derivative (LLSD) approach to radar analysis is a method of quantifying gradients in radar data by fitting a least squares plane to a neighborhood of range bins and finding its slope. When applied to radial velocity fields, for example, LLSD yields part of the azimuthal (rotational) and radial (divergent) components of horizontal shear, which, under certain geometric assumptions, estimate one-half of the two-dimensional vertical vorticity and horizontal divergence equations, respectively. Recent advances in computational capacity as well as increased usage of LLSD products by the meteorological community have motivated an overhaul of the LLSD methodology's application to radar data. This paper documents the mathematical foundation of the updated LLSD approach, including a complete derivation of its equation set, discussion of its limitations, and considerations for other types of implementation. In addition, updated azimuthal shear calculations are validated against theoretical vorticity using simulated circulations. Applications to nontraditional radar data and new applications to nonvelocity radar data including reflectivity at horizontal polarization, spectrum width, and polarimetric moments are also explored. These LLSD gradient calculations may be leveraged to identify and interrogate a wide variety of severe weather phenomena, either directly by operational forecasters or indirectly as part of future automated algorithms. [ABSTRACT FROM AUTHOR]

Synthetic studies toward the gibberellin family of natural products are reported. An oxidative dearomatization/Diels-Alder cascade assembles the carbon skeleton as a [2.2.2]-bicycle, which is then transformed to the [3.2.1]-bicyclic gibberellin core via a novel Lewis acid catalyzed rearrangement. Strategic synthetic handles allow for late-stage modification of the gibberellin skeleton and provides efficient access to this important family of natural compounds. [ABSTRACT FROM AUTHOR]

Synthetic studies toward maoecrystal V are reported. An oxidative dearomatization/Diels--Alder cascade to assemble the natural product carbocyclic core in one step is proposed. A facile electrocyclization is shown to suppress the intramolecular allene Diels--Alder pathway. This obstacle is alleviated via a stepwise approach with an allene equivalent to access the key cyclopentadiene-fused [2.2.2]-bicyclic core. Upon treatment with Lewis acid, the proposed intramolecular hetero-Diels--Alder reaction is cleanly and unexpectedly diverted either via C--C bond-forming fragmentation to the spiro-indene product (when R = OMe) or via elimination (when R = H). [ABSTRACT FROM AUTHOR]

Thediversity of elements among U.S. Food and Drug Administration(FDA) approved pharmaceuticals is analyzed and reported, with a focuson atoms other than carbon, hydrogen, oxygen, and nitrogen. Our analysisreveals that sulfur, chlorine, fluorine, and phosphorous representabout 90% of elemental substitutions, with sulfur being the fifthmost used element followed closely by chlorine, then fluorine andfinally phosphorous in the eighth place. The remaining 10% of substitutionsare represented by 16 other elements of which bromine, iodine, andiron occur most frequently. The most detailed parts of our analysisare focused on chlorinated drugs as a function of approval date, diseasecondition, chlorine attachment, and structure. To better aid our chlorinedrug analyses, a new poster showcasing the structures of chlorinatedpharmaceuticals was created specifically for this study. Phosphorus,bromine, and iodine containing drugs are analyzed closely as well,followed by a discussion about other elements. [ABSTRACT FROM AUTHOR]

'Concord' grapevines (Vitis labruscana Bailey) can readily develop iron deficiency-induced leaf chlorosis when grown on calcareous or high pH soils. Iron (Fe) chelates are often applied to the soil to remedy chlorosis but can vary in their stability and effectiveness at high pH. We transplanted own-rooted 1-year-old 'Concord' grapevines into a peat-based medium adjusted to pH 7.5 and fertigated them with 0, 0.5, 1.0, 2.0, or 4 mg.L-1 Fe from Fe-EDDHA [ferric ethylenediamine di (o-hydroxyphenylacetic) acid] to determine the effectiveness of this Fe chelate for alleviating Fe deficiency-induced chlorosis at high pH. Vines were sampled midseason for iron, chlorophyll, CO2 assimilation, and photosystem II quantum efficiency (PSII) and at the end of the season for leaf area, dry weight, and cane length. We found that leaf total Fe concentration was similar across all treatments, but active Fe (extracted with 0.1 N HCI) concentration increased as the rate of Fe-EDDHA increased. Chlorophyll concentration increased curvilinearly as applied Fe increased and was highly correlated with active Fe concentration. CO2 assimilation, stomatal conductance, and PSII were very low without any supplemental Fe and increased rapidly in response to Fe application. Total leaf area, foliar dry weight, and cane length all increased as Fe application increased to 1 mg·L-1 Fe, but above this rate, a further increase in Fe did not significantly increase growth. Our results demonstrate that Fe-EDDHA is very effective in alleviating Fe deficiency-induced leaf chlorosis in 'Concord' grapevines grown at high pH, which provides a foundation for continuing research related to the optimum rate and timing of application of Fe-EDDHA in 'Concord' vineyards on calcareous soils. Compared with total Fe, leaf "active Fe" better indicates the actual Fe status of 'Concord' vines. [ABSTRACT FROM AUTHOR]

Two experiments were conducted to evaluate effects of water-soluble fertilizer concentration (WSF) and substrate-pH on growth, foliar nutrient content, and chlorosis of seed geranium (Pelargonium × hortorum) “Ringo Scarlet.” Geraniums were grown for 21 days in a 70% peat-30% perlite substrate. Experiment 1 included four pre-plant lime rates (pH 3.8, 4.3, 4.8, and 5.5), and plants were irrigated using 1X, 2X, 3X, and 4X rates of a WSF containing 75N-11P-84K-72Ca-17 Mg-23S-0.375Fe-0.185 Mn-0.019Zn-0.028Cu-0.058B-0.006Mo. Iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu) were supplied as EDTA-chelated micronutrients. Experiment 2 included six lime rates (initial pH 3.2, 4.3, 5.2, 6.3, 7.0, and 7.5) at 2X and 4X WSF concentrations. Two forms of chlorosis were observed, consistent with micronutrient toxicity at moderately-low pH (4.3–5.2) and micronutrient deficiency at pH above 6.3. At very low substrate-pH, below 4.0, cation content decreased in leaf tissue, anion content increased, and plants appeared healthier than at pH 4.3–5.2. The decline in cation uptake at low pH was possibly the result of low substrate Ca, low-pH stress on membrane or cation channel activity, or competition between H+ and cations for root binding sites. At pH 4.3–5.2, plants were stunted, with chlorotic and necrotic spotting, necrotic leaf margins, and high tissue levels of Fe and Mn. At pH 5.5 (Experiment 1) or 6.3 (Experiment 2), plants appeared healthy. Iron and Mn declined at pH above 6.3, and interveinal chlorosis was observed. WSF concentration affected the pH range at which chlorosis occurred, intensifying toxicity symptoms at pH 4.3–5.2, and ameliorating deficiency at pH > 6.3. Results emphasize that an acceptable pH range for healthy growth can be affected by the applied fertilizer concentration. [ABSTRACT FROM AUTHOR]

Despite the increasing numbers of women students in medical schools, focused attention on their perceptions about medical school and the medical profession remain underexamined. These perceptions are important to understand, particularly since women students are likely burdened with a host of gender norms related to work, family, and their future roles as physicians. Early experiences in medical school offer important insights into the larger student experience and are tied to academic outcomes and feelings of belonging. To examine early experiences of women medical students, this qualitative study used sensemaking theory to describe the current context and "story" of ideal worker norms. Critical qualitative interviews of 38 women students were performed during their first 2 months of medical school and explored both how the students perceived and experienced ideal worker norms, and how they made sense of the "story" of ideal worker norms. The participants described ways they encountered gendering and ideal worker norms through displays of nurturing behaviour, expectations to balance a future family, and whether they looked or acted the part of a doctor. This article highlights the challenges women medical students are already aware they will face, the opportunities they look forward to, and the strengths they anticipate leaning on to navigate their profession. Results from this study have implications for women medical students' learning experiences and transitions into medical school and for faculty, staff, and scholars concerned with challenging gendering norms that shape medical education. Women students are seen to demonstrate knowledge of "ideal worker norms" very early in medical school; the authors explore how they made sense of norms and began to navigate the gendered organization of their chosen careers. [ABSTRACT FROM AUTHOR]

The article offers information related to tools and techniques recommended by the National Oceanic and Atmospheric Administration (NOAA)/National Weather Service (NWS) for flash flood detection and warning operations. It mentions certain products that were evaluated during Hydrometeorological Testbed-Hydrology (HMT-Hydro) experiment such as MRMS suite and FLASH suite featuring their product scale and spatiotemporal resolution.

Summary: Self-rooted, 10-month-old, uniform tea [Camellia sinensis (L.) O. Kuntze cv. Huangguanyin] plants were supplied for 17 weeks with 0, 40, 80, 160, 400, or 1000μM phosphorus (P) to investigate the effects of P supply on root citrate and malate release, the concentrations of malate and citrate and the activities of acid-metabolizing enzymes in leaves and roots. Root malate release and accumulation was induced by both 0 and 40μM P, while root citrate release and accumulation was induced only by 0μM P. Phosphorus-deficiency-induced malate and citrate release coincided with higher concentrations of root malate and citrate. The higher concentrations of malate and citrate were accompanied by increased activities of phosphoenolpyruvate carboxylase (PEPC), phosphoenolpyruvate phosphatase (PEPP), citrate synthase (CS) and NAD-malic enzyme (NAD-ME) and decreased activities of pyruvate kinase (PK), NADP-ME and NADP-isocitrate dehydrogenase (NADP-IDH) in roots. In contrast to roots, malate accumulated in the leaves only in response to 0μM P, and no change was observed in citrate levels. The P-deficiency-induced leaf malate accumulation coincided with increased activities of NADP-ME, NAD-ME and PK. Overall, the P-deficiency-induced changes in organic acid (OA) metabolism differed between roots and leaves. The high tolerance of tea plants to P-deficiency might be involved in two major processes: (a) increasing the availability of P by inducing root release of OA anions; and (b) improving the ability to use P efficiently by inducing bypass enzymes involved in tissue P economy. [ABSTRACT FROM AUTHOR]

Summary: Seedlings of sour pummelo (Citrus grandis) were irrigated daily for 18 weeks with nutrient solution containing four phosphorus (P) levels (50, 100, 250 and 500μM KH2PO4) and two aluminum (Al) levels [0 (−Al) and 1.2mM AlCl3·6H2O (+Al)]. Both malate and citrate concentrations in +Al leaves decreased with increasing P supply, but their concentrations in −Al leaves did not change in response to P supply. The concentrations of malate under 50μM P and of citrate under 50 and 100μM P were higher in +Al leaves than in −Al ones, but malate concentration was lower in +Al leaves than in −Al ones under 500μM P. There was no difference in root malate and citrate concentrations among different P and Al combinations except for an increase in malate and citrate under 50μM P+0mM Al and a slight decrease in malate under 50μM P+1.2mM Al. The activities of acid-metabolizing enzymes (citrate synthase, aconitase, phosphoenolpyruvate carboxylase, NADP-isocitrate dehydrogenase, phosphoenolpyruvate phosphatase, NAD-malate dehydrogenase, NADP-malic enzyme and pyruvate kinase) in most cases were less affected by P and Al interactions in roots compared to the leaves. Our results support the hypothesis that changes in organic acid metabolism differ between roots and leaves of C. grandis in response to P and Al interactions. [Copyright &y& Elsevier]

Summary: Seedlings of sweet orange (Citrus sinensis) were fertilized for 14 weeks with boron (B)-free or B-sufficient (2.5 or 10μM H3BO3) nutrient solution every other day. Boron deficiency resulted in an overall inhibition of plant growth, with a reduction in root, stem and leaf dry weight (DW). Boron-starved leaves showed decreased CO2 assimilation and stomatal conductance, but increased intercellular CO2 concentrations. Activities of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), NADP-glyceraldehyde-3-phosphate dehydrogenase (NADP-GAPDH) and stromal fructose-1,6-bisphosphatase (FBPase) were lower in B-deficient leaves than in controls. Contents of glucose, fructose and starch were increased in B-deficient leaves while sucrose was decreased. Boron-deficient leaves displayed higher or similar superoxide dismutase (SOD), ascorbate peroxidase (APX), monodehydroascorbate reductase (MDAR) and glutathione reductase (GR) activities, while dehydroascorbate reductase (DHAR) and catalase (CAT) activities were lower. Expressed on a leaf area or protein basis, B-deficient leaves showed a higher ascorbate (AsA) concentration, but a similar AsA concentration on a DW basis. For reduced glutathione (GSH), we found a similar GSH concentration on a leaf area or protein basis and an even lower content on a DW basis. Superoxide anion (O2.-) generation, malondialdehyde (MDA) concentration and electrolyte leakage were higher in B-deficient than in control leaves. In conclusion, CO2 assimilation may be feedback-regulated by the excessive accumulation of starch and hexoses in B-deficient leaves via direct interference with chloroplast function and/or indirect repression of photosynthetic enzymes. Although B-deficient leaves remain high in activity of antioxidant enzymes, their antioxidant system as a whole does not provide sufficient protection from oxidative damage. [Copyright &y& Elsevier]

An abstract of the article on the synthesis of the oxidative dearomatization by Qingliang Yang et al. is presented.