[Analysis of the prevalence of anticoagulant therapy in patients with cognitive disorders and cerebral amyloid angiopathy (CAA)]. / Analyse zur Häufigkeit einer gerinnungshemmenden Medikation bei Patientinnen mit kognitiven Störungen und zerebraler Amyloidangiopathie (CAA).

OBJECTIVES: To investigate the prevalence of coincident anticoagulation in patients with cognitive disorders and possible or probable cerebral amyloid angiopathy (CAA) as well as the relationship between the presence of oral anticoagulation and CAA-specific lesion load. MATERIALS AND METHODS: Patients with subjective cognitive decline (SCD), amnestic and non-amnestic mild cognitive impairment (aMCI/naMCI), Alzheimer's disease (AD), mixed dementia (MD) and vascular dementia (VD) who presented to our outpatient dementia clinic between February 2016 and October 2020 were included in this retrospective analysis. Patients underwent cranial magnetic resonance imaging (MRI). MRI data sets were analyzed regarding the presence of CAA-related MRI biomarkers to determine CAA prevalence. Presence of anticoagulant therapy was determined by chart review. RESULTS: Within the study period, 458 patients (209 male, 249 female, mean age 73.2 ± 9.9 years) with SCD (n = 44), naMCI (n = 40), aMCI (n = 182), AD (n = 120), MD (n = 68) and VD (n = 4) were analyzed. A total of 109 patients (23.8%) were diagnosed with possible or probable CAA. CAA prevalence was highest in aMCI (39.4%) and MD (28.4%). Of patients with possible or probable CAA, 30.3% were under platelet aggregation inhibition, 12.8% were treated with novel oral anticoagulants and 3.7% received phenprocoumon treatment. Regarding the whole study cohort, patients under oral anticoagulation showed more cerebral microbleeds (p = 0.047). There was no relationship between oral anticoagulation therapy and the frequency of cortical superficial siderosis (p = 0.634). CONCLUSION: CAA is a frequent phenomenon in older patients with cognitive disorders. Almost half of CAA patients receive anticoagulant therapy. Oral anticoagulation is associated with a higher number of cortical and subcortical microbleeds.

Volcaniclastic density currents explain widespread and diverse seafloor impacts of the 2022 Hunga Volcano eruption.

The impacts of large terrestrial volcanic eruptions are apparent from satellite monitoring and direct observations. However, more than three quarters of all volcanic outputs worldwide lie submerged beneath the ocean, and the risks they pose to people, infrastructure, and benthic ecosystems remain poorly understood due to inaccessibility and a lack of detailed observations before and after eruptions. Here, comparing data acquired between 2015 - 2017 and 3 months after the January 2022 eruption of Hunga Volcano, we document the far-reaching and diverse impacts of one of the most explosive volcanic eruptions ever recorded. Almost 10 km3 of seafloor material was removed during the eruption, most of which we conclude was redeposited within 20 km of the caldera by long run-out seafloor density currents. These powerful currents damaged seafloor cables over a length of >100 km, reshaped the seafloor, and caused mass-mortality of seafloor life. Biological (mega-epifaunal invertebrate) seafloor communities only survived the eruption where local topography provided a physical barrier to density currents (e.g., on nearby seamounts). While the longer-term consequences of such a large eruption for human, ecological and climatic systems are emerging, we expect that these previously-undocumented refugia will play a key role in longer-term ecosystem recovery.

Evaluation of Processed Nerve Allograft in Peripheral Nerve Surgery: A Systematic Review and Critical Appraisal.

Peripheral nerve injuries cause substantial problems when not treated properly. A specific problem is reconstruction of nerve defects, which can be treated in different ways. This study aimed to systematically review whether processed nerve allograft (PNA) is justified in reconstruction of a nerve defect in patients after posttraumatic or iatrogenic peripheral nerve injury and to compare PNA with other established methods. Methods: A systematic review with a focused question, PICO (patient, intervention, comparison, outcome) and constraints, was performed. A structured literature search, including several databases, was done to evaluate the existing evidence for outcomes and postoperative complications related to PNA. The certainty of evidence was classified according to Grading of Recommendations, Assessment, Development and Evaluations. Results: No conclusions, concerning differences in outcome of nerve reconstruction using PNA compared with the use of nerve autograft or conduits, could be drawn. The level of certainty for all evaluated outcomes was very low (⊕◯◯◯). Most published studies lack a control group to patients treated with PNA; being only descriptive, making it difficult to compare PNA with established methods without substantial risk of bias. For studies including a control group, the scientific evidence was of very low certainty, due to a low number of included patients, and large, undefined loss of patients during follow-up, rendering a high risk of bias. Finally, the authors often had financial disclosures. Conclusion: Properly conducted randomized controlled trial studies on the use of PNA in reconstruction of peripheral nerve injuries are needed to establish recommendations in clinical practice.

Bouncing off Ove: Old men's readings of the novel A Man Called Ove as a cultural representation of ageing masculinity.

In recent years, there has been a rise in portrayals of greying protagonists in popular fiction, often featuring older people in humorous and heart-warming stories. An emerging genre within this literature is the "geezer and grump lit", a genre where older people are active protagonists, and while often portrayed as grumpy "'usually turn out to have a heart of gold'" (Swinnen, 2019). A notable example of a book in this genre is the internationally bestselling novel A Man Called Ove (2012) by the Swedish author Fredrik Backman. Telling the story of the 59-year-old Ove who sets out to take his own life, the novel can be understood not only as a cultural representation of ageing, but more specifically a cultural representation of ageing masculinity. But how is this popular novel read and responded to by old men themselves? This article builds on a focus group study with Swedish men aged 65-92 who read and discussed A Man Called Ove. The aim of this article is thus to explore how men read the novel and how these readings function as ways of constructing, negotiating and challenging ageing masculinity and the old man as a gendered and aged position. Findings of the study show how discussion of the novel generated a variety of "imaginary positions" through which the participants made sense of what it means to be an old man in contemporary Sweden, including positions such as the active aspiring ageing man, the passive lonely old man, the embodied and vulnerable old man, and the dutiful old man. Future research should explore how other literary genres may provide ways of understanding how old men's gendered and aged subjectivities are constructed.

Noncanonical Role of Telomerase in Regulation of Microvascular Redox Environment With Implications for Coronary Artery Disease.

Telomerase reverse transcriptase (TERT) (catalytic subunit of telomerase) is linked to the development of coronary artery disease (CAD); however, whether the role of nuclear vs. mitchondrial actions of TERT is involved is not determined. Dominant-negative TERT splice variants contribute to decreased mitochondrial integrity and promote elevated reactive oxygen species production. We hypothesize that a decrease in mitochondrial TERT would increase mtDNA damage, promoting a pro-oxidative redox environment. The goal of this study is to define whether mitochondrial TERT is sufficient to maintain nitric oxide as the underlying mechanism of flow-mediated dilation by preserving mtDNA integrity.Immunoblots and quantitative polymerase chain reaction were used to show elevated levels of splice variants α- and ß-deletion TERT tissue from subjects with and without CAD. Genetic, pharmacological, and molecular tools were used to manipulate TERT localization. Isolated vessel preparations and fluorescence-based quantification of mtH2O2 and NO showed that reduction of TERT in the nucleus increased flow induced NO and decreased mtH2O2 levels, while prevention of mitochondrial import of TERT augmented pathological effects. Further elevated mtDNA damage was observed in tissue from subjects with CAD and initiation of mtDNA repair mechanisms was sufficient to restore NO-mediated dilation in vessels from patients with CAD. The work presented is the first evidence that catalytically active mitochondrial TERT, independent of its nuclear functions, plays a critical physiological role in preserving NO-mediated vasodilation and the balance of mitochondrial to nuclear TERT is fundamentally altered in states of human disease that are driven by increased expression of dominant negative splice variants.

Time- and dose-dependent volume decreases in subcortical grey matter structures of glioma patients after radio(chemo)therapy.

Background and purpose: Radiotherapy (RT) is an adjuvant treatment option for glioma patients. Side effects include tissue atrophy, which might be a contributing factor to neurocognitive decline after treatment. The goal of this study was to determine potential atrophy of the hippocampus, amygdala, thalamus, putamen, pallidum and caudate nucleus in glioma patients having undergone magnetic resonance imaging (MRI) before and after RT. Materials and methods: Subcortical volumes were measured using T1-weighted MRI from patients before RT (N = 91) and from longitudinal follow-ups acquired in three-monthly intervals (N = 349). The volumes were normalized to the baseline values, while excluding structures touching the clinical target volume (CTV) or abnormal tissue seen on FLAIR imaging. A multivariate linear effects model was used to determine if time after RT and mean RT dose delivered to the corresponding structures were significant predictors of tissue atrophy. Results: The hippocampus, amygdala, thalamus, putamen, and pallidum showed significant atrophy after RT as function of both time after RT and mean RT dose delivered to the corresponding structure. Only the caudate showed no dose or time dependant atrophy. Conversely, the hippocampus was the structure with the highest atrophy rate of 5.2 % after one year and assuming a mean dose of 30 Gy. Conclusion: The hippocampus showed the highest atrophy rates followed by the thalamus and the amygdala. The subcortical structures here found to decrease in volume indicative of radiosensitivity should be the focus of future studies investigating the relationship between neurocognitive decline and RT.

Direct radiation exposure of the eye lenses in cranial computed tomography and exposure reduction through radiographer training.

INTRODUCTION: Ionizing radiation can cause increased opacity of the lens and later lead to radiation-induced cataract. Therefore, the eye lens should be positioned outside of the direct radiation beam in cranial computed tomography (CCT). If this is not possible, protective measures must be taken, which includes the use of external lens protectors. In this study we assess whether direct radiation exposure of the eyes in CCT can be reduced by trained radiographers and whether the use of eye lens protectors improves after training. METHODS: First, we evaluated 763 non-enhanced CCT regarding direct radiation exposure of eyeballs and eye lenses and usage of lens shielding. Afterwards, we trained radiographers to avoid radiation exposure of the eyes by head adjustment and protectors and assessed the improvements in a subsequent study of 678 CCT. We tried to identify factors that influenced radiation exposure of the eye lens. RESULTS: After training, frequency of radiation exposure of lenses was significantly reduced by 5.9% (220/763 patients in pre- vs. 155/678 patients in post-training group, p = 0.01). The use of external lens protectors significantly increased after training by 9.8% (37/763 patients in pre- vs. 99/678 patients in post-training group, p < 0.001). The absence of tiltable headrest was a risk factor for increased eye lens radiation exposure in the pre-training group. The presence of cervical spine immobilizer was associated with more frequent radiation exposure of the lenses in the pre- and post-training group. CONCLUSIONS: Radiographer training and the use of tiltable headrest lead to reduction of radiation exposure to the eye lens. IMPLICATIONS FOR PRACTICE: Radiographer training is an effective method to reduce eye lens exposure in CCT. The usage of tiltable headrest minimizes the radiation exposure of the lenses.

[Current findings on the coincidence of cerebral amyloid angiopathy and Alzheimer's disease]. / Aktuelle Befunde zur Koinzidenz von zerebraler Amyloidangiopathie und Alzheimer-Erkrankung.

Cerebral amyloid angiopathy (CAA) is closely related to Alzheimer's disease (AD) despite having distinct pathomechanisms. The CAA modulates cognitive impairment within AD by synergistic effects. The pathophysiologic relations are complex and incompletely understood, possibly due to the heterogeneous nature of CAA with its different subtypes. Both diseases are characterized by a pathologic amyloid metabolism but the pathologic processing of amyloid precursor proteins is distinct. The manifestation of vascular and parenchymal amyloid deposits can either overlap or occur independently and isolated. The investigation of the specific contribution of co-occurring CAA within AD to cognitive deficits requires diagnostic methods that sufficiently identify CAA severity and complexity as well as detailed neuropsychological testing to precisely characterize the cognitive deficits and to draw conclusions regarding their etiology.

[Intracerebral hemorrhage under platelet inhibition and oral anticoagulation in patients with cerebral amyloid angiopathy]. / Intrazerebrale Blutungen unter Plättchenaggregationshemmung und oraler Antikoagulation bei Patienten mit zerebraler Amyloidangiopathie.

Oral anticoagulation in patients with cerebral amyloid angiopathy is a therapeutic challenge. The association of cerebral amyloid angiopathy with intracerebral hemorrhage, a high mortality of intracerebral hemorrhage especially under oral anticoagulation and the high risk of recurrent bleeding require a multidisciplinary approach and a thorough risk-benefit analysis. Vitamin K antagonists increase the risk of intracerebral bleeding and the accompanying mortality by 60% and should be avoided if possible or reserved for special clinical situations (e.g. mechanical aortic valve replacement). Treatment with novel oral anticoagulants and antiplatelet drugs also increases the risk of cerebral bleeding and therefore needs a thorough risk-benefit evaluation. An interventional left atrial appendage closure is a promising therapeutic option especially in patients with an absolute arrythmia with atrial fibrillation. Furthermore, other clinical implications in patients with cerebral amyloid angiopathy are the subject of this review of the literature, such as special characteristics after acute ischemic stroke and the necessary secondary prophylaxis, with previous intracerebral hemorrhage and in patients with cognitive deficits.

Reduced seawater pH alters marine biofilms with impacts for marine polychaete larval settlement.

Ocean acidification (OA) can negatively affect early-life stages of marine organisms, with the key processes of larval settlement and metamorphosis potentially vulnerable to reduced seawater pH. Settlement success depends strongly on suitable substrates and environmental cues, with marine biofilms as key settlement inducers for a range of marine invertebrate larvae. This study experimentally investigated (1) how seawater pH determines growth and community composition of marine biofilms, and (2) whether marine biofilms developed under different pH conditions can alter settlement success in the New Zealand serpulid polychaete Galeolaria hystrix. Biofilms were developed under six pH(T) treatments (spanning from 7.0 to 8.1 [ambient]) in a flow-through system for up to 14 months. Biofilms of different ages (7, 10 and 14 months) were used to assay successful settlement of competent G. hystrix larvae reared under ambient conditions. Biofilm microbiomes were characterized through amplicon sequencing of the small subunit ribosomal rRNA gene (16S and 18S). Biofilm community composition was stable over time within each pH treatment and biofilm age did not affect larval settlement selectivity. Seawater pH treatment strongly influenced biofilm community composition, as well as subsequent settlement success when biofilms were presented to competent Galeolaria larvae. Exposure to biofilms incubated under OA-treatments caused a decrease in larval settlement of up to 40% compared to the ambient treatments. We observed a decrease in settlement on biofilms relative to ambient pH for slides incubated at pH 7.9 and 7.7. This trend was reversed at pH 7.4, resulting in high settlement, comparable to ambient biofilms. Settlement decreased on biofilms from pH 7.2, and no settlement was observed on biofilms from pH 7.0. For the first time, we show that long-term incubation of marine biofilms under a wide range of reduced seawater pH treatments can alter marine biofilms in such a way that settlement success in marine invertebrates can be compromised.

Feedback mechanisms stabilise degraded turf algal systems at a CO2 seep site.

Human activities are rapidly changing the structure and function of coastal marine ecosystems. Large-scale replacement of kelp forests and coral reefs with turf algal mats is resulting in homogenous habitats that have less ecological and human value. Ocean acidification has strong potential to substantially favour turf algae growth, which led us to examine the mechanisms that stabilise turf algal states. Here we show that ocean acidification promotes turf algae over corals and macroalgae, mediating new habitat conditions that create stabilising feedback loops (altered physicochemical environment and microbial community, and an inhibition of recruitment) capable of locking turf systems in place. Such feedbacks help explain why degraded coastal habitats persist after being initially pushed past the tipping point by global and local anthropogenic stressors. An understanding of the mechanisms that stabilise degraded coastal habitats can be incorporated into adaptive management to better protect the contribution of coastal systems to human wellbeing.

Regulating, fostering and preserving: the production of sexual normates through cognitive ableism and cognitive othering.

People with cognitive disabilities are commonly positioned as risky sexual subjects. This article discusses the discursive production of sexual normates in the form of desirable and normative able-minded sexual subjects, in scientific research on the sexuality and cognitive disabilities of younger and older individuals (in particular those with dementia). We identify three interrelated discourses: regulating sexuality; fostering sexuality; and preserving sexuality. The first of these, regulation, pathologises sexuality of people with cognitive disabilities as faulty and in need of restriction. The second discourse, fostering, is more affirmative and argues for educating for a 'healthy' sexuality of people with cognitive disabilities, to mitigate risks of abuse. This discourse is more salient with younger people. The third discourse, preservation, in contrast, is more visible with older people with dementia and affirms sexuality so long as it is consistent with a 'genuine' or 'authentic' sexuality of the past. In conclusion, scientific research reinforces the cultural ideal of the rational and autonomous individual (and as such the mature/adult) capable of making independent decisions and engaging in healthy, good sex, based on stable sexual identities. Findings demonstrate how age intersects with cognitive ableism to intensify the cultural anxiety that exists around the sexualities of people with cognitive disabilities.

Homogeneous environmental selection dominates microbial community assembly in the oligotrophic South Pacific Gyre.

Oligotrophic subtropical gyres are the largest continuous biomes on Earth and play a key role in global biogeochemical cycles. Microbial communities govern primary production and carbon cycling in the oligotrophic South Pacific Gyre, yet the ecological processes which underpin microbial biogeography in the region remain understudied. We investigated microbial biogeography and community assembly processes at three depths over a ~2,000-km the transect was longitudinal, so ran from 32°S, 170°W to 32°S, 152°W). Thus the latitude (32°S) was constant. Microbial communities in the surface waters (15 and 50 m) were remarkably similar across the transect, whilst communities at the deep chlorophyll maximum were distinct from the surface waters and displayed greater compositional heterogeneity. An ecological null model approach indicated that homogeneous selection was the dominant community assembly process in both the surface waters (100%) and at the deep chlorophyll maximum (91.81%), although variable selection (2.34%) and stochastic processes (5.85%) had a minor influence at the deep chlorophyll maximum. Homogeneous selection (76.69%77.90%), dispersal limitation (15.00%-20.05%) and variable selection (3.01%-7.11%) influenced community assembly between the surface waters and the deep chlorophyll maximum. Seawater density and temperature, which were correlated, were the most important environmental modulators of the balance between stochastic and deterministic assembly processes. Our findings demonstrate remarkable similarity in microbial community composition across longitudinal scales in the oligotrophic South Pacific Gyre, underpinned by strong environmental selection which overwhelms the influence of ecological drift. These data significantly advance our understanding of microbial community dynamics in the oligotrophic subtropical gyres which dominate the Earth's surface.

Subtle bacterioplankton community responses to elevated CO2 and warming in the oligotrophic South Pacific gyre.

Bacterioplankton play a critical role in primary production, carbon cycling, and nutrient cycling in the oligotrophic ocean. To investigate the effect of elevated CO2 and warming on the composition and function of bacterioplankton communities in oligotrophic waters, we performed two trace-metal clean deck board incubation experiments during the New Zealand GEOTRACES transect of the South Pacific gyre (SPG). High-throughput amplicon sequencing of the 16S rRNA gene revealed that bacterioplankton community composition was distinct between the fringe and ultra-oligotrophic centre of the SPG and changed consistently in response to elevated CO2 at the ultra-oligotrophic centre but not at the mesotrophic fringe of the SPG. The combined effects of elevated CO2 and warming resulted in a high degree of heterogeneity between replicate communities. Community-level protein synthesis rates (3 H-Leucine incorporation) and bacterioplankton abundance were not affected by elevated CO2 alone or in combination with warming at the fringe or ultra-oligotrophic centre of the SPG. These data suggest bacterioplankton community responses to elevated CO2 may be modulated by nutrient regimes in open ocean ecosystems and highlight the need for further investigation in expanding oligotrophic subtropical gyres.

Reduced diffusion in normal appearing white matter of glioma patients following radio(chemo)therapy.

BACKGROUND AND PURPOSE: Standard treatment of high grade gliomas includes gross tumour resection followed by radio(chemo)therapy. Radiotherapy inevitably leads to irradiation of normal brain tissue. The goal of this prospective, longitudinal study was to use MRI to quantify normal appearing white and grey matter changes following radiation treatment as a function of dose and time after radiotherapy. MATERIALS AND METHODS: Pre-radiotherapy (proton or photon therapy) MRI and follow-up MRIs collected in 3 monthly intervals thereafter were analysed for 22 glioma patients and included diffusion tensor imaging, quantitative T1, T2* and proton density mapping. Abnormal tissue was excluded from analysis. MR signal changes were quantified within different dose bin regions for grey and white matter and subsequently for whole brain white matter. RESULTS: We found significant reductions in mean diffusivity, radial diffusivity, axial diffusivity and T2* in normal appearing white matter regions receiving a radiation dose as low as 10-20 Gy within the observational period of up to 18 months. The magnitude of these changes increased with the received radiation dose and progressed with time after radiotherapy. Whole brain white matter also showed a significant reduction in radial diffusivity as a function of radiation dose and time after radiotherapy. No significant changes were observed in grey matter. CONCLUSION: Diffusion tensor imaging and T2* imaging revealed normal appearing white matter changes following radiation treatment. The changes were dose dependant and progressed over time. Further work is needed to understand the underlying tissue changes and to correlate the observed diffusion changes with late brain malfunctions.

Relationships between protein and energy consumed from milk replacer and starter and calf growth and first-lactation production of Holstein dairy cows.

The objective was to determine relationships between protein and energy consumed from milk replacer and starter and calf growth and first-lactation production of Holstein heifer calves. Milk replacer and starter protein intake and metabolizable energy (ME) intake data were collected from 4,534 Holstein heifer calves for growth and 3,627 Holstein cows for production from birth year of 2004 through 2014. Calves from 3 commercial dairy farms were assigned to 45 different calf research trials at the University of Minnesota Southern Research and Outreach Center, Waseca, Minnesota, from 3 to 195 d of life. Calves were moved to heifer growers at 6 mo of age, and calves were returned to their farm of birth a few weeks before calving. Most calves (85%) were fed a 20% crude protein and 20% fat milk replacer at a rate of 0.57 kg/calf daily. Metabolizable energy and protein consumed from milk replacer and starter were calculated for each individual calf for 6 and 8 wk of age. Mixed model analyses were conducted to determine the effect of protein and energy consumed from both milk replacer and starter on calf growth and first-lactation 305-d production of milk, fat, and protein, adjusting for herd, season of birth, year, average daily gain (ADG), and calf trial. Calves with ADG >0.80 kg/d consumed more combined protein and ME than calves with lower ADG. Protein and ME intake from calf starter affected growth more than protein and ME intake from milk replacer because most calves were fed the same fixed amount of milk replacer. Calves born during the fall and winter had greater combined protein and ME intake than calves born during the spring and summer. Milk replacer protein and ME intake did not have a relationship with first-lactation 305-d milk, fat, and protein production. However, starter protein and ME intake during the first 6 and 8 wk of age had a significant positive relationship with first-lactation 305-d milk, fat, and protein production. Consequently, combined protein and combined ME intake had a positive effect on 305-d milk, fat, and protein production. Variance in protein and ME intake was high, suggesting that additional factors affect calf growth during the first 8 wk of life and milk production in first lactation.

Dementia and the gender trouble?: Theorising dementia, gendered subjectivity and embodiment.

Despite person-centred approaches increasingly focusing on looking at the person in dementia instead of the pathology, the role of gender in dementia has been little explored. This article discusses how pervasive discourses on a loss of self and dementia as abject are interwoven with a de-gendering of persons with dementia. The cultural anxiety that dementia evokes in terms of loss of bodily and cognitive control could also be linked to a failure to normatively and intelligibly express gender when living with dementia. As a way to sustain personhood for people with dementia and challenge discourses on people with dementia as 'non-people', person-centred approaches have emphasised the collaborative work of carers, relatives and persons with dementia. Often implicitly, this also involves a 're-gendering' of persons with dementia where gendered biographies and pasts are upheld and gendered embodied selfhood is maintained through, for example, dress, hair and other aspects of appearance. This re-gendering could be of great significance for people with dementia to become intelligible as persons. Still, dementia studies must further consider non-normative expressions of gender and involve feminist theorising on gender as a power asymmetry since some embodiments and selves are more likely to be sustained in dementia than others.

A 100-Year Review: Calf nutrition and management.

The first calf paper, published in the May 1919 issue of the Journal of Dairy Science (JDS), described factors affecting birth body weight of different breeds of calves. Other studies were done on nonmilk ingredients, growth charts were developed, and early weaning was followed to conserve milk fed to calves. Calf papers did not report use of statistics to control or record variation or to determine whether treatment means were different. Many experiments were more observational than comparative. Typically fewer than 5 calves, and sometimes 1 or 2 calves, were used per treatment. During the next 20 yr, calf studies increased and included colostrum feeding, milk and milk replacer feeding, minerals and vitamins, and fats and oils. Many concepts fundamental to current knowledge and understanding of digestion, rumen development, and milk replacer formulation were developed during this period. In addition, the concept of using antibiotic growth promoters in dairy calf diets was first evaluated and developed during the 1950s. During the 20-yr period of January 1957 through December 1976, a large number of universities in the United States and 1 in Canada contributed almost 150 papers on a variety of calf-related topics. These topics included genetics, physiology of the calf, review of calf immunity, antibiotic feeding, and milk replacer ingredients. This became the golden era of calf rumen development studies, which also engendered studies of calf starter rations and ingredients. A classic review of management, feeding, and housing studies summarized research related to calf feeding and management systems up to that point with an emphasis on maintaining calf growth and health while reducing labor and feed costs. It was also during this period that metric measurements replaced English units. In the 20-yr period from 1977 to 1996, more than 400 articles on calf nutrition and management were published in JDS. With the growing research interest in calves, a paper outlining standardized procedures for conducting and reporting data from calf experiments was first published. A very active area of calf nutrition research from the late 1970s to the mid 1980s was colostrum quality, feeding, and preservation; more than 60 such research articles were published in the journal during this time. Various nonmilk protein sources were evaluated. Extensive studies were done evaluating trace and major mineral requirements in calves along with some vitamin studies. Throughout the 1970s, 1980s, and 1990s, the primary objective of most calf research was how to wean healthy, adequately grown calves at an early age-generally less than 30 d of age. This program was reviewed in a 1979 publication. Research on calf starter ingredients, nutrient composition, and additives was minimal in the 1980s and 1990s given the importance of starter intake to the success of early weaning, but the role of water intake in starter intake and growth was established. Research on issues with calves continued to increase during the last 20-yr period as evidenced by publication of more than 580 articles in JDS as well as many more in other refereed journals. In addition to papers contributed by several universities in the United States and Canada, the number of papers authored by scientists at universities and institutes in other countries increased dramatically during this period. Factors influencing colostral antibody absorption, heat treatment of colostrum, and efficacy of colostrum supplements and replacers were reported. Most studies in this period related to nutrition. Studies were published supporting greater neonatal growth rates from feeding more milk replacer but with a higher crude protein content than traditional. Protein energy effects on growth and body composition were evaluated in concert with greater growth rates. Milk and nonmilk protein sources in milk replacers along with AA supplementation were evaluated. Limited studies were done with fat sources and fatty acid supplementation along with trace minerals and fat-soluble vitamins. Waste milk feeding and heat treatment became more prevalent. Studies established starter ingredient palatability and use of forage when fed with pelleted starters. With the advent of automatic milk and milk replacer feeders, factors influencing how and when to wean were established. Research programs established factors affecting calf behavior and welfare. Several databases were evaluated along with various published studies, and established calf growth during the first 2 mo was subsequently reflected in first- and later-lactation milk production of those calves. A new area of calf research that emerged from 1997 on was the effects of maternal environment and nutrition on calf health, growth, and future productivity. From a mechanistic standpoint, the field of epigenetics seems likely to explain many of these phenomena. Some possibilities for future calf nutrition and management were elaborated.