Detecting shifts in nonlinear dynamics using Empirical Dynamic Modeling with Nested-Library Analysis.

Abrupt changes in system states and dynamical behaviors are often observed in natural systems; such phenomena, named regime shifts, are explained as transitions between alternative steady states (more generally, attractors). Various methods have been proposed to detect regime shifts from time series data, but a generic detection method with theoretical linkage to underlying dynamics is lacking. Here, we provide a novel method named Nested-Library Analysis (NLA) to retrospectively detect regime shifts using empirical dynamic modeling (EDM) rooted in theory of attractor reconstruction. Specifically, NLA determines the time of regime shift as the cutting point at which sequential reduction of the library set (i.e., the time series data used to reconstruct the attractor for forecasting) optimizes the forecast skill of EDM. We illustrate this method on a chaotic model of which changing parameters present a critical transition. Our analysis shows that NLA detects the change point in the model system and outperforms existing approaches based on statistical characteristics. In addition, NLA empirically detected a real-world regime shift event revealing an abrupt change of Pacific Decadal Oscillation index around the mid-1970s. Importantly, our method can be easily generalized to various systems because NLA is equation-free and requires only a single time series.

Fluctuating interaction network and time-varying stability of a natural fish community.

Ecological theory suggests that large-scale patterns such as community stability can be influenced by changes in interspecific interactions that arise from the behavioural and/or physiological responses of individual species varying over time. Although this theory has experimental support, evidence from natural ecosystems is lacking owing to the challenges of tracking rapid changes in interspecific interactions (known to occur on timescales much shorter than a generation time) and then identifying the effect of such changes on large-scale community dynamics. Here, using tools for analysing nonlinear time series and a 12-year-long dataset of fortnightly collected observations on a natural marine fish community in Maizuru Bay, Japan, we show that short-term changes in interaction networks influence overall community dynamics. Among the 15 dominant species, we identify 14 interspecific interactions to construct a dynamic interaction network. We show that the strengths, and even types, of interactions change with time; we also develop a time-varying stability measure based on local Lyapunov stability for attractor dynamics in non-equilibrium nonlinear systems. We use this dynamic stability measure to examine the link between the time-varying interaction network and community stability. We find seasonal patterns in dynamic stability for this fish community that broadly support expectations of current ecological theory. Specifically, the dominance of weak interactions and higher species diversity during summer months are associated with higher dynamic stability and smaller population fluctuations. We suggest that interspecific interactions, community network structure and community stability are dynamic properties, and that linking fluctuating interaction networks to community-level dynamic properties is key to understanding the maintenance of ecological communities in nature.

Antipsychotic medications and severe sepsis in schizophrenia: A nested case-control study.

BACKGROUND: Sepsis constitutes a condition that involves life-threatening organ dysfunction induced by severe infection. This nested case-control study investigated risk factors for severe sepsis and whether antipsychotic use is associated with severe sepsis risk in patients with schizophrenia, a topic that has not been comprehensively explored in previous studies. METHODS: We selected 39,432 patients with schizophrenia aged between 15 and 65 years from Taiwan's Psychiatric Inpatient Medical Claims database for the period 2000-2012. The case group comprised patients with severe sepsis after their first psychiatric admission (n = 1382). The case and control groups were randomly matched (1:4) by age, sex and first psychiatric admission (year) and finally comprised 1382 and 5528 individuals, respectively. We employed multivariable conditional logistic regression to identify (1) risk factors (physical illnesses and nonpsychiatric medications) and (2) antipsychotic-severe sepsis associations. RESULTS: Higher numbers of psychiatric admissions and physical illnesses such as delirium, cerebrovascular disease and cancer were significantly associated with a higher risk of severe sepsis. Furthermore, severe sepsis was associated with the use of antithrombotic agents, systemic corticosteroids and agents targeting the renin-angiotensin system. Clozapine (adjusted risk ratio = 1.65) and quetiapine (adjusted risk ratio = 1.59) use were associated with an increased risk of severe sepsis. The use of more than one antipsychotic drug could further increase this risk. CONCLUSION: Several physical illnesses and nonpsychiatric medications increase the risk of severe sepsis in patients with schizophrenia. Specifically, clozapine or quetiapine use significantly increased the risk of severe sepsis in these patients.

Is the N2A Category Still Necessary for Oral Cancer Patients After Extranodal Extension Upgrade?

BACKGROUND: The presence of single-node metastasis (Ns) sometimes could be encountered in patients with oral squamous cell carcinoma (OSCC). The survival outcome for different Ns should be worthy of discussion. METHODS: Patients diagnosed with OSCC at the National Taiwan University Hospital between January 2007 and December 2018 were reviewed. All patients with Ns were classified into two groups: with and without extranodal extension (ENE). RESULTS: We analyzed 311 OSCC patients with Ns: 77 (24.76%) with and 234 (75.24%) without ENE. Lymph node (LN) >3 cm was the only significant factor associated with ENE (odds ratio 17.21, p < 0.001). The 5-year, disease-free survival of N1/N2A and N3B patients was 60.5% and 49.4%, respectively (p = 0.04), and the 5-year overall survival was 63.1% and 33.6%, respectively (p = 0.0001). Four fifths of Ns patients with LN >3 cm were upgraded to N3B category as ENE+. Postoperative radiotherapy (PORT) could provide significant benefit in regional control for Ns patients with (p = 0.03) and without (p = 0.0004) other adverse features. After multivariant Cox analysis, ENE+ was a modest and significant risk factor for disease-free (p = 0.08) and overall survival (p = 0.001). By contrast, the LN>3cm and N2A category were not significant risk factors for disease-free and overall survival. CONCLUSIONS: For OSCC patients with Ns, the survival outcome between N3B category and N1/N2A category was significantly different. After ENE+ upgrades (>80%), there were fewer N2A patients, and these patients became more comparable to N1 patients. PORT could significantly improve regional control for Ns patients.

Myasthenia gravis and independent risk factors for recurrent infection: a retrospective cohort study.

BACKGROUND: Approximately 10% to 20% of myasthenia gravis (MG) patients have experienced a myasthenic crisis (MC), which contributes to morbidity and mortality. MC triggered by infection is associated with poor outcomes. However, there is a lack of prognostic factors that clinicians can utilize to target interventions for preventing recurrent infection-triggered MC. This study aimed to characterize clinical manifestations, comorbidities, and biochemical profiles associated with recurrent infection-triggered MC in MG patients. METHODS: This retrospective study included 272 MG patients hospitalized with an infection requiring at least 3 days of antibiotics from January 2001 to December 2019. Patients were further stratified into non-recurrent or recurrent infection groups. Clinical features such as gender, age, concomitant diseases, acetylcholine receptor antibodies and biochemical data (including electrolytes and coagulants), muscle strength of pelvic and shoulder girdle, bulbar and respiratory function, management with an endotracheal tube, Foley catheter, or plasmapheresis, duration of hospitalization, and culture pathogens were recorded. RESULTS: The recurrent infection group was significantly older than the non-recurrent group (median age, 58.5 versus 52.0 years). Pneumonia was the most common infection and Klebsiella pneumoniae was the most common pathogen. The presence of concomitant diabetes mellitus, activated partial thromboplastin time prolongation, the duration of hospitalization, and hypomagnesaemia were independently associated with recurrent infection. The presence of deep vein thrombosis, thymic cancer, and electrolyte imbalances i.e., hypokalemia, and hypoalbuminemia were significantly associated with a risk for infection. The influence of endotracheal intubation, anemia, and plasmapheresis during hospitalization were inconsistent. CONCLUSIONS: The independent risk factors for recurrent infections in MG patients identified in this study include the presence of concomitant diabetes mellitus, hypomagnesaemia, activated partial thromboplastin time prolongation, and longer duration of hospitalization, highlighting the need for targeted interventions to prevent recurrent infections in this population. Further research and prospective studies are warranted to validate these findings and refine interventions for optimizing patient care.

Characteristics of acute ischemic stroke in patients with Nephrotic syndrome.

The incidence of ischemic stroke (IS) is higher in nephrotic syndrome (NS) patients compared to general population. However, there is limited information on the specific characteristics to stroke patients with NS. In this study, we aimed to examine the clinical manifestations of acute IS in a large group of NS patients, comparing to those without NS. We conducted a retrospective cohort study to compare the clinical presentations of acute IS in patients with and without NS. This study was a multi-institutional study and used data from Chang Gung Research Database of Taiwan from 1 January 2001, to 31 December 2017. A total of 233 IS patients with NS and 1358 IS patients without NS were enrolled. The median age of participants was 68 (range: 59-79) years. The risk of dependent functional status (modified Rankin Scale score≧3) after IS was higher in NS patients compared to those without NS (Odd ratio (OR) 4.02, 95% confidence interval (CI) 2.39 to 6.76, p < 0.001), particularly in stroke subtypes as small-artery occlusion (OR 8.02, 95% CI 3.94 to 16.32, p < 0.001), and stroke of undetermined etiology (OR 2.47, CI 1.06 to 5.76, p = 037). The risks of mortality or stroke recurrence within 30 days were similar between the two groups for all stroke subtypes. In conclusion, NS was associated with a higher risk of functional dependence following IS. Intensive treatment and rehabilitation should be considered for IS patients with NS.

Upregulation of APAF1 and CSF1R in Peripheral Blood Mononuclear Cells of Parkinson's Disease.

Increased oxidative stress and neuroinflammation play a crucial role in the pathogenesis of Parkinson's disease (PD). In this study, the expression levels of 52 genes related to oxidative stress and inflammation were measured in peripheral blood mononuclear cells of the discovery cohort including 48 PD patients and 25 healthy controls. Four genes, including ALDH1A, APAF1, CR1, and CSF1R, were found to be upregulated in PD patients. The expression patterns of these genes were validated in a second cohort of 101 PD patients and 61 healthy controls. The results confirmed the upregulation of APAF1 (PD: 0.34 ± 0.18, control: 0.26 ± 0.11, p < 0.001) and CSF1R (PD: 0.38 ± 0.12, control: 0.33 ± 0.10, p = 0.005) in PD patients. The expression level of APAF1 was correlated with the scores of the Unified Parkinson's Disease Rating Scale (UPDRS, r = 0.235, p = 0.018) and 39-item PD questionnaire (PDQ-39, r = 0.250, p = 0.012). The expression level of CSF1R was negatively correlated with the scores of the mini-mental status examination (MMSE, r = -0.200, p = 0.047) and Montréal Cognitive Assessment (MoCA, r = -0.226, p = 0.023). These results highly suggest that oxidative stress biomarkers in peripheral blood may be useful in monitoring the progression of motor disabilities and cognitive decline in PD patients.

Evidence-based trends and association between symptom disturbance and physical activity among pregnant women: A longitudinal study.

BACKGROUND: Women usually decrease their physical activity (PA) after becoming pregnant. The change in PA may influence their symptom distress (SD). The changes and correlations between SD and PA throughout pregnancy remain unclear. AIMS: The aims of this study were to describe PA and SD trajectories across all three trimesters and examine their correlations during pregnancy. METHODS: A repeated-measure longitudinal study with convenience sampling at a hospital in Northern Taiwan was performed. Participants were recruited at 8-16 weeks of gestation, and two follow-up visits were performed at 24-28 weeks of gestation (second trimester) and after 36 weeks of gestation (third trimester). A total of 225 participants completed the study. The participants completed the Pregnancy Physical Activity Questionnaire (PPAQ) and Pregnancy-related Symptom Disturbance Scale (PSD), and sociodemographic and prenatal variables were recorded. RESULTS: Throughout pregnancy, SD decreased then increased, showing an overall upward trend, whereas PA showed the opposite pattern, increasing then decreasing, with an overall downward trend. Sedentary activity was positively correlated with both physical and psychological SD during the second and third trimesters. Exceeding the Institute of Medicine's recommendations for gestational weight gain, having childcare support, sport/exercise-type, and light-intensity PA were negatively associated with the physical and psychological SD, while a history of miscarriage and sedentary-intensity PA were positively associated with the physical and psychological SD. LINKING EVIDENCE TO ACTION: While several factors, including light-intensity PA, were found negatively associated with the physical and psychological SD, sedentary-intensity PA were positively associated with the physical and psychological SD, our findings shed light on future intervention strategies to relieve SD and decrease sedentary behavior among pregnant women.

The Influence of the Electron Density in Acyl Protecting Groups on the Selectivity of Galactose Formation.

The stereoselective formation of 1,2-cis-glycosidic bonds is a major bottleneck in the synthesis of carbohydrates. We here investigate how the electron density in acyl protecting groups influences the stereoselectivity by fine-tuning the efficiency of remote participation. Electron-rich C4-pivaloylated galactose building blocks show an unprecedented α-selectivity. The trifluoroacetylated counterpart with electron-withdrawing groups, on the other hand, exhibits a lower selectivity. Cryogenic infrared spectroscopy in helium nanodroplets and density functional theory calculations revealed the existence of dioxolenium-type intermediates for this reaction, which suggests that remote participation of the pivaloyl protecting group is the origin of the high α-selectivity of the pivaloylated building blocks. According to these findings, an α-selective galactose building block for glycosynthesis is developed based on rational considerations and is subsequently employed in automated glycan assembly exhibiting complete stereoselectivity. Based on the obtained selectivities in the glycosylation reactions and the results from infrared spectroscopy and density functional theory, we suggest a mechanism by which these reactions could proceed.

Establishment of a new classification system for chronic inflammatory demyelinating polyneuropathy based on unsupervised machine learning.

INTRODUCTION/AIMS: A model for predicting responsiveness to immunotherapy in patients with chronic inflammatory demyelinating polyneuropathy (CIDP) has not been well established. We aimed to establish a new classifier for CIDP patients based on clinical characteristics, laboratory findings, and electrophysiological features. METHODS: The clinical, laboratory, and electrophysiological features of 172 treatment-naïve patients with CIDP between 2003 and 2019 were analyzed using an unsupervised hierarchical clustering. The identified pivotal features were used to establish simple classifications using a tree-based model. RESULTS: Three clusters were identified: 1, n = 65; 2, n = 70; and 3, n = 37. Patients in Cluster 1 scored lower on the disability assessment score before treatment. More patients in Clusters 2 (90.0%) fulfilled demyelinating criteria than patients in Cluster 1 (30.8%, p < .001). Cluster 3 had more patients with chronic kidney disease (CKD) (27.0%) and hypoalbuminemia (3.40 g/dL) than did Cluster 2 (CKD: 0%, p < .001; hypoalbuminemia: 4.09 g/dL, p < .001). The responsiveness to pulse steroid therapy was higher in Cluster 2 (70.0%) than in Clusters 1 (31.8%; p = .043) and 3 (25.0%; p = .014). A tree-based model with four pivotal features classified patients in our cohort into new clusters with high accuracy (89.5%). DISCUSSION: The established hierarchical clustering with the tree-based model identified key features contributing to differences in disease severity and response to pulse steroid therapy. This classification system could assist clinicians in the selection of treatments and could also help researchers by clustering patients for clinical treatment trials.

Oral presentation assessment and image reading behaviour on brain computed tomography reading in novice clinical learners: an eye-tracking study.

BACKGROUND: To study whether oral presentation (OP) assessment could reflect the novice learners' interpretation skills and reading behaviour on brain computed tomography (CT) reading. METHODS: Eighty fifth-year medical students were recruited, received a 2-hour interactive workshop on how to read brain CT, and were assigned to read two brain CT images before and after instruction. We evaluated their image reading behaviour in terms of overall OP post-test rating, the lesion identification, and competency in systematic image reading after instruction. Students' reading behaviour in searching for the target lesions were recorded by the eye-tracking technique and were used to validate the accuracy of lesion reports. Statistical analyses, including lag sequential analysis (LSA), linear mixed models, and transition entropy (TE) were conducted to reveal temporal relations and spatial complexity of systematic image reading from the eye movement perspective. RESULTS: The overall OP ratings [pre-test vs. post-test: 0 vs. 1 in case 1, 0 vs. 1 in case 2, p < 0.001] improved after instruction. Both the scores of systematic OP ratings [0 vs.1 in both cases, p < 0.001] and eye-tracking studies (Case 1: 3.42 ± 0.62 and 3.67 ± 0.37 in TE, p = 0.001; Case 2: 3.42 ± 0.76 and 3.75 ± 0.37 in TE, p = 0.002) showed that the image reading behaviour changed before and after instruction. The results of linear mixed models suggested a significant interaction between instruction and area of interests for case 1 (p < 0.001) and case 2 (p = 0.004). Visual attention to the target lesions in the case 1 assessed by dwell time were 506.50 ± 509.06 and 374.38 ± 464.68 milliseconds before and after instruction (p = 0.02). However, the dwell times in the case 2, the fixation counts and the frequencies of accurate lesion diagnoses in both cases did not change after instruction. CONCLUSION: Our results showed OP performance may change concurrently with the medical students' reading behaviour on brain CT after a structured instruction.

The First Guillain-Barr? Syndrome After SARS-CoV-2 Vaccination in Taiwan.

PURPOSE: Guillain-Barre syndrome (GBS) is an immune-mediated disease of the peripheral nerves and could be fatal and has severe neurologic complications. This study herein reports the clinical course of the first patient of GBS after SARS-CoV-2 Oxford/AstraZeneca vaccination in Taiwan. CASE REPORT: A 38-year-old woman who presented with progressive numbness and weakness of both upper and lower limbs over 1 week. Ascending patterns was noted, and bilateral leg were more severe with diffused absence of deep tendon reflex. Clinical examination and investigation findings confirmed with the diagnosis of GBS. Deterioration of muscle power and respiratory failure had developed during the hospitalization. She had no common GBS predisposing history, but she had received her first SARS-CoV-2 Oxford/AstraZeneca vaccination intramuscularly 10 days prior to her symptoms. Clinical symptoms had much improved after double filtration plasmapheresis. CONCLUSION: Our case is the first case of GBS developed after AstraZeneca vaccine injection in Taiwan, presenting with atypical manifestation of early facial and bulbar involvement. The vaccination associated GBS should be closely monitored as other safety profile, since it may result in respiratory failure and severe neurologic complications. Keyword: Guillain-Barre Syndrome, SARS-CoV-2 Vaccination.

Reconstructing large interaction networks from empirical time series data.

Reconstructing interactions from observational data is a critical need for investigating natural biological networks, wherein network dimensionality is usually high. However, these pose a challenge to existing methods that can quantify only small interaction networks. Here, we proposed a novel approach to reconstruct high-dimensional interaction Jacobian networks using empirical time series without specific model assumptions. This method, named "multiview distance regularised S-map," generalised the state space reconstruction to accommodate high dimensionality and overcome difficulties in quantifying massive interactions with limited data. When evaluating this method using time series generated from theoretical models involving hundreds of interacting species, estimated strengths of interaction Jacobians were in good agreement with theoretical expectations. Applying this method to a natural bacterial community helped identify important species from the interaction network and revealed mechanisms governing the dynamical stability of a bacterial community. The proposed method overcame the challenge of high dimensionality in large natural dynamical systems.

Statistical Analysis of Glycosylation Reactions.

Chemical synthesis is one of the practical approaches to access carbohydrate-based natural products and their derivatives with high quality and in a large quantity. However, stereoselectivity during the glycosylation reaction is the main challenge because the reaction can generate both α- and ß-glycosides. The main focus of the present article is the concept of recent mechanistic studies that have applied statistical analysis and quantitation for defining stereoselective changes during the reaction process. Based on experimental evidence, a detailed discussion associated with the mechanism and degree of influence affecting the stereoselective outcome of glycosylation is included.

Characteristics of ischemic stroke and intracranial hemorrhage in patients with nephrotic syndrome.

BACKGROUND: The incidence of cerebral stroke, including ischemic infarction and intracranial hemorrhage (ICH), increases in patients with nephrotic syndrome (NS). However, the clinical characteristics of patients with NS and stroke remain elusive. We aimed to investigate the clinical presentation and prognosis among patients with NS and ischemic stroke (IS) or ICH. METHODS: We conducted a population-based retrospective cohort study of patients with NS and acute stroke using the Chang Gung Research Database of Taiwan from January 1, 2001, to December 31, 2017. The participants were recruited from the 7 branches of Chang Gung Memorial Hospital. RESULTS: A total of 233 patients with IS and 57 patients with ICH were enrolled. The median age was 60 (52-70) years. The prevalence rates of hyperlipidemia, hyperuricemia, and smoking were higher in IS than in ICH. IS demonstrated lower white blood cell count (7.80 vs. 8.92 × 109/L) and high-sensitivity C-reactive protein level (33.42 vs. 144.10 nmol/L) and higher cholesterol (5.74 vs. 4.84 mmol/L), triglyceride (1.60 vs. 1.28 mmol/L), and albumin (24 vs. 18 g/L) levels compared with ICH. The dependent functional status and 30-day mortality were higher in ICH than in IS. The risk factors for 30-day mortality for patients with NS and stroke were coronary artery disease (CAD), ICH, and total anterior circulation syndrome. The multivariate Cox regression analysis revealed that CAD was positively associated with 30-day mortality in patients with IS (hazard ratio 24.58, 95 % CI 1.48 to 408.90). In patients with ICH, CAD and subarachnoid hemorrhage were positively associated with 30-day mortality (hazard ratio 5.49, 95 % CI 1.54 to 19.56; hazard ratio 6.32, 95 % CI 1.57 to 25.53, respectively). CONCLUSIONS: ICH demonstrated a higher risk of dependence and 30-day mortality compared with IS in patients with NS. Intensive monitoring and treatment should be applied particularly in patients with NS and ICH.

Automated Quantification of Hydroxyl Reactivities: Prediction of Glycosylation Reactions.

The stereoselectivity and yield in glycosylation reactions are paramount but unpredictable. We have developed a database of acceptor nucleophilic constants (Aka) to quantify the nucleophilicity of hydroxyl groups in glycosylation influenced by the steric, electronic and structural effects, providing a connection between experiments and computer algorithms. The subtle reactivity differences among the hydroxyl groups on various carbohydrate molecules can be defined by Aka, which is easily accessible by a simple and convenient automation system to assure high reproducibility and accuracy. A diverse range of glycosylation donors and acceptors with well-defined reactivity and promoters were organized and processed by the designed software program "GlycoComputer" for prediction of glycosylation reactions without involving sophisticated computational processing. The importance of Aka was further verified by random forest algorithm, and the applicability was tested by the synthesis of a Lewis A skeleton to show that the stereoselectivity and yield can be accurately estimated.

Body Size, Light Intensity, and Nutrient Supply Determine Plankton Stoichiometry in Mixotrophic Plankton Food Webs.

Trophic strategy determines stoichiometry of plankton. In general, heterotrophic zooplankton have lower and more stable C∶N and C∶P ratios than photoautotrophic phytoplankton, whereas mixotrophic protists, which consume prey and photosynthesize, have stoichiometry between zooplankton and phytoplankton. As trophic strategies change with cell size, body size may be a key trait influencing eukaryotic plankton stoichiometry. However, the relationship between body size and stoichiometry remains unclear. Here we measured plankton size-fractionated C∶N ratios under different intensities of light and nutrient supply in subtropical freshwater and marine systems. We found a unimodal body size-C∶N ratio pattern, with a maximum C∶N ratio at ∼50 µm diameter in marine and freshwater systems. Moreover, the variation in C∶N ratios is explained mainly by body size, followed by light intensity and nutrient concentration. To investigate the mechanisms behind this unimodal pattern, we constructed a size-based plankton food web model in which the trophic strategy and C∶N ratio are an emerging result. Our model simulations reproduce the unimodal pattern with a C∶N ratio of photoautotrophs ≤50 µm increasing with body size due to increase of photosynthetic carbon, whereas C∶N ratios of organisms >50 µm decrease with size due to decreasing photoautotrophic but increasing heterotrophic uptake. Based on our field observations and simulation, we extend the classic "light-nutrient" theory that determines plankton C∶N ratio to include body size and trophic strategy dependency. We conclude that body size and size-dependent uptake of resources (light, nutrients, and prey) determine plankton stoichiometry at various light and nutrient supplies.

Long-term warming destabilizes aquatic ecosystems through weakening biodiversity-mediated causal networks.

Understanding how ecosystems will respond to climate changes requires unravelling the network of functional responses and feedbacks among biodiversity, physicochemical environments, and productivity. These ecosystem components not only change over time but also interact with each other. Therefore, investigation of individual relationships may give limited insights into their interdependencies and limit ability to predict future ecosystem states. We address this problem by analyzing long-term (16-39 years) time series data from 10 aquatic ecosystems and using convergent cross mapping (CCM) to quantify the causal networks linking phytoplankton species richness, biomass, and physicochemical factors. We determined that individual quantities (e.g., total species richness or nutrients) were not significant predictors of ecosystem stability (quantified as long-term fluctuation of phytoplankton biomass); rather, the integrated causal pathway in the ecosystem network, composed of the interactions among species richness, nutrient cycling, and phytoplankton biomass, was the best predictor of stability. Furthermore, systems that experienced stronger warming over time had both weakened causal interactions and larger fluctuations. Thus, rather than thinking in terms of separate factors, a more holistic network view, that causally links species richness and the other ecosystem components, is required to understand and predict climate impacts on the temporal stability of aquatic ecosystems.

Mapping Mechanisms in Glycosylation Reactions with Donor Reactivity: Avoiding Generation of Side Products.

The glycosylation reaction, which is key for the studies on glycoscience, is challenging due to its complexity and intrinsic side reactions. Thioglycoside is one of the most widely used glycosyl donors in the synthesis of complex oligosaccharides. However, one of the challenges is its side reactions, which lower its yield and limits its efficiency, thereby requiring considerable effort in the optimization process. Herein, we reported a multifaceted experimental approach that reveals the behaviors of side reactions, such as the intermolecular thioaglycon transformation and N-glycosyl succinimides, via the glycosyl intermediate. Our mechanistic proposal was supported by low temperature NMR studies that can further be mapped by utilizing relative reactivity values. Accordingly, we also presented our findings to suppress the generation of side products in solving this particular problem for achieving high-yield glycosylation reactions.