Milk production declines as dairy cows enter late lactation, resulting in reduced milk quality and negatively impacting milk processability, such as rennet coagulation time (RCT), milk pH and ethanol stability (ES), leading to seasonality issues for milk processors. Multispecies forages, containing grass, legume and herb species, require lower N inputs and are of interest to dairy farmers. However, little is known about the effect of grazing multispecies forages on milk processability characteristics in late lactation dairy cows. Forty-five autumn-calving dairy cows in late lactation were allocated to 1 of 3 grazing forages; perennial ryegrass (PRG; Lolium perenne), perennial ryegrass and white clover (Trifolium pratense) (PRGWC), and a 6 – species multispecies forage (MULTI) containing perennial ryegrass, timothy (Phleum pratense), white clover, red clover (Trifolium repens), chicory (Cichorium intybus) and plantain (Plantago lanceolata). Cows were allocated 12 kg DM grazed forage and supplemented with a grass – silage TMR and concentrate. Forage DMI was significantly lower for cows grazing PRG. Milk yield increased when cows grazed PRGWC (18.07 kg/d) and MULTI (17.84 kg/d) compared to PRG (16.08 kg/d). Milk RCT (mins) and ES (%) were unaffected by treatment. However, offering cows PRGWC and MULTI increased the concentration of C18:2 cis – 9, 12 and C18:3 cis – 9, 12, 15 in milk compared to PRG. Compared to PRG, grazing forages containing clover and herb species improved milk yield and beneficially altered milk fatty acid profile in late lactation dairy cows without negatively impacting milk processability.

Childhood adversity is common and associated with elevated risk for transdiagnostic psychopathology. Reward processing has been implicated in the link between adversity and psychopathology, but whether it serves as a mediator or moderator is unclear. This study examined whether alterations in behavioral and neural reward processing function as a mechanism or moderator of psychopathology outcomes following adversity experiences, including threat (i.e., trauma) and deprivation. A longitudinal community sample of 10–15-year-old youths was assessed across two waves (Wave 1: n = 228; Wave 2: n = 206). Wave 1 assessed adverse experiences, psychopathology symptoms, reward processing on a monetary incentive delay task, and resting-state fMRI. At Wave 2, psychopathology symptoms were reassessed. Greater threat experiences were associated with blunted behavioral reward sensitivity, which, in turn, predicted increases in depression symptoms over time and mediated the prospective association between threat and depression symptoms. In contrast, reward sensitivity moderated the association between deprivation experiences and prospective externalizing symptoms such that the positive association of deprivation with increasing externalizing symptoms was absent for children with high levels of reward sensitivity.

Two extant frameworks – the harshness-unpredictability model and the threat-deprivation model – attempt to explain which dimensions of adversity have distinct influences on development. These models address, respectively, why, based on a history of natural selection, development operates the way it does across a range of environmental contexts, and how the neural mechanisms that underlie plasticity and learning in response to environmental experiences influence brain development. Building on these frameworks, we advance an integrated model of dimensions of environmental experience, focusing on threat-based forms of harshness, deprivation-based forms of harshness, and environmental unpredictability. This integrated model makes clear that the why and the how of development are inextricable and, together, essential to understanding which dimensions of the environment matter. Core integrative concepts include the directedness of learning, multiple levels of developmental adaptation to the environment, and tradeoffs between adaptive and maladaptive developmental responses to adversity. The integrated model proposes that proximal and distal cues to threat-based and deprivation-based forms of harshness, as well as unpredictability in those cues, calibrate development to both immediate rearing environments and broader ecological contexts, current and future. We highlight actionable directions for research needed to investigate the integrated model and advance understanding of dimensions of environmental experience.

Child maltreatment gives rise to atypical patterns of social functioning with peers which might be particularly pronounced in early adolescence when peer influence typically peaks. Yet, few neuroimaging studies in adolescents use peer interaction paradigms to parse neural correlates of distinct maltreatment exposures. This fMRI study examines effects of abuse, neglect, and emotional maltreatment (EM) among 98 youth (n = 58 maltreated; n = 40 matched controls) using an event-related Cyberball paradigm affording assessment of both social exclusion and inclusion across early and mid-adolescence (≤13.5 years, n = 50; >13.5 years, n = 48). Younger adolescents showed increased activation to social exclusion versus inclusion in regions implicated in mentalizing (e.g., superior temporal gyrus). Individual exposure-specific analyses suggested that neglect and EM coincided with less reduction of activation to social exclusion relative to inclusion in the dorsal anterior cingulate cortex/pre-supplementary motor area (dACC/pre-SMA) among younger versus older adolescents. Integrative follow-up analyses showed that EM accounted for this dACC/pre-SMA activation pattern over and above other exposures. Moreover, age-independent results within respective exposure groups revealed that greater magnitude of neglect predicted blunted exclusion-related activity in the parahippocampal gyrus, while EM predicted increased activation to social exclusion in the precuneus/posterior cingulate cortex.

To provide comprehensive information on the epidemiology and burden of respiratory syncytial virus hospitalisation (RSVH) in preterm infants, a pooled analysis was undertaken of seven multicentre, prospective, observational studies from across the Northern Hemisphere (2000–2014). Data from all 320–356 weeks' gestational age (wGA) infants without comorbidity were analysed. RSVH occurred in 534/14 504 (3.7%) infants; equating to a rate of 5.65 per 100 patient-seasons, with the rate in individual wGA groups dependent upon exposure time (P = 0.032). Most RSVHs (60.1%) occurred in December–January. Median age at RSVH was 88 days (interquartile range (IQR): 54–159). Respiratory support was required by 82.0% of infants: oxygen in 70.4% (median 4 (IQR: 2–6) days); non-invasive ventilation in 19.3% (median 3 (IQR: 2–5) days); and mechanical ventilation in 10.2% (median 5 (IQR: 3–7) days). Intensive care unit admission was required by 17.9% of infants (median 6 days (IQR: 2–8) days). Median overall hospital length of stay (LOS) was 5 (IQR: 3–8) days. Hospital resource use was similar across wGA groups except for overall LOS, which was shortest in those born 35 wGA (median 3 vs. 4–6 days for 32–34 wGA; P < 0.001). Strategies to reduce the burden of RSVH in otherwise healthy 32–35 wGA infants are indicated.

The flow-induced vibration of a sphere elastically mounted in the cross-flow direction with imposed feedback rotation was investigated experimentally. The application of rotation provides a means to exercise control over the vibration response of axisymmetric three-dimensional objects. Both the rotational amplitude, which was imposed in proportion to sphere transverse displacement, and the phase of the control signal were varied over a broad parameter space comprising: a non-dimensionalised proportional gain ($0.5\leqslant K_{p}^{\ast }\leqslant 2$); rotation phase ($0^{\circ }\leqslant \unicode[STIX]{x1D719}_{rot}\leqslant 360^{\circ }$), which is the phase between the applied sphere rotation and the transverse displacement; and reduced velocity ($3\leqslant$$U^{\ast }\leqslant 20$). The corresponding Reynolds number range was ($3900\lesssim Re\lesssim 25\,800$). The structural vibration, fluid forces and wake structure were examined to characterise the effect of the imposed rotation. It was found that the rotation not only altered the magnitude of the vibration response, either amplifying or attenuating the response depending on operating conditions, but it also altered the reduced velocity at which vibrations commenced, the vibration frequency and periodicity and significantly altered the phase between the transverse fluid force and displacement. It was possible to almost completely suppress the vibration in the mode I, mode II and mode III transition regimes for imposed rotation over the ranges $90^{\circ }\lesssim$$\unicode[STIX]{x1D719}_{rot}\lesssim 180^{\circ }$, $15^{\circ }\lesssim$$\unicode[STIX]{x1D719}_{rot}\lesssim 135^{\circ }$ and $0^{\circ }\lesssim$$\unicode[STIX]{x1D719}_{rot}\lesssim 120^{\circ }$, respectively. In particular, this could be achieved at effective rotation rates well below those required by using open-loop control (Sareen et al., J. Fluid Mech., vol. 837, 2018, pp. 258–292). Past the peak of mode II, a ‘galloping-like’ response, similar to that reported by Vicente-Ludlam et al. (J. Fluid Mech., vol. 847, 2018, pp. 93–118) for the circular cylinder, was observed with an increase in vibration amplitude of up to 368 % at the highest reduced velocity tested ($U^{\ast }=20$). Particle image velocimetry measurements revealed a change in the timing and spatial position of the streamwise vortex structures with imposed rotation. Contrary to what has been observed for the circular cylinder, however, no de-synchronisation between vortex shedding and sphere motion was observed.

Exposure to adverse events is prevalent among youths and robustly associated with risk for depression, particularly during adolescence. The Dimensional Model of Adversity and Psychopathology (DMAP) distinguishes between adverse events that expose youths to deprivation versus threat, positing unique mechanisms of risk (cognitive functioning deficits for deprivation, and altered fear and emotion learning for threat) that may require different approaches to intervention. We examined whether deprivation and threat were distinctly associated with behavioral measures of cognitive processes and autonomic nervous system function in relation to depression symptom severity in a community sample of early adolescents (n = 117; mean age 12.73 years; 54.7% male). Consistent with DMAP, associations between threat and depression symptoms, and between economic deprivation and depression symptoms, were distinctly moderated by physiological and cognitive functions, respectively, at baseline but not follow-up. Under conditions of greater cognitive inhibition, less exposure to deprivation was associated with lower symptom severity. Under conditions of blunted resting-state autonomic response (electrodermal activity and respiratory sinus arrhythmia), greater exposure to threat was associated with higher symptom severity. Our findings support the view that understanding risk for youth depression requires parsing adversity: examining distinct roles played by deprivation and threat, and the associated cognitive and biological processes.

This experimental study investigates the effect of imposed rotary oscillation on the flow-induced vibration of a sphere that is elastically mounted in the cross-flow direction, employing simultaneous displacement, force and vorticity measurements. The response is studied over a wide range of forcing parameters, including the frequency ratio $f_{R}$ and velocity ratio $\unicode[STIX]{x1D6FC}_{R}$ of the oscillatory forcing, which vary between $0\leqslant f_{R}\leqslant 5$ and $0\leqslant \unicode[STIX]{x1D6FC}_{R}\leqslant 2$. The effect of another important flow parameter, the reduced velocity, $U^{\ast }$, is also investigated by varying it in small increments between $0\leqslant U^{\ast }\leqslant 20$, corresponding to the Reynolds number range of $5000\lesssim Re\lesssim 30\,000$. It has been found that when the forcing frequency of the imposed rotary oscillations, $f_{r}$, is close to the natural frequency of the system, $f_{nw}$, (so that $f_{R}=f_{r}/f_{nw}\sim 1$), the sphere vibrations lock on to $f_{r}$ instead of $f_{nw}$. This inhibits the normal resonance or lock-in leading to a highly reduced vibration response amplitude. This phenomenon has been termed ‘rotary lock-on’, and occurs for only a narrow range of $f_{R}$ in the vicinity of $f_{R}=1$. When rotary lock-on occurs, the phase difference between the total transverse force coefficient and the sphere displacement, $\unicode[STIX]{x1D719}_{total}$, jumps from $0^{\circ }$ (in phase) to $180^{\circ }$ (out of phase). A corresponding dip in the total transverse force coefficient $C_{y\,(rms)}$ is also observed. Outside the lock-on boundaries, a highly modulated amplitude response is observed. Higher velocity ratios ($\unicode[STIX]{x1D6FC}_{R}\geqslant 0.5$) are more effective in reducing the vibration response of a sphere to much lower values. The mode I sphere vortex-induced vibration (VIV) response is found to resist suppression, requiring very high velocity ratios ($\unicode[STIX]{x1D6FC}_{R}>1.5$) to significantly suppress vibrations for the entire range of $f_{R}$ tested. On the other hand, mode II and mode III are suppressed for $\unicode[STIX]{x1D6FC}_{R}\geqslant 1$. The width of the lock-on region increases with an increase in $\unicode[STIX]{x1D6FC}_{R}$. Interestingly, a reduction of VIV is also observed in non-lock-on regions for high $f_{R}$ and $\unicode[STIX]{x1D6FC}_{R}$ values. For a fixed $\unicode[STIX]{x1D6FC}_{R}$, when $U^{\ast }$ is progressively increased, the response of the sphere is very rich, exhibiting characteristically different vibration responses for different $f_{R}$ values. The phase difference between the imposed rotary oscillation and the sphere displacement $\unicode[STIX]{x1D719}_{rot}$ is found to be crucial in determining the response. For selected $f_{R}$ values, the vibration amplitude increases monotonically with an increase in flow velocity, reaching magnitudes much higher than the peak VIV response for a non-rotating sphere. For these cases, the vibrations are always locked to the forcing frequency, and there is a linear decrease in $\unicode[STIX]{x1D719}_{rot}$. Such vibrations have been termed ‘rotary-induced vibrations’. The wake measurements in the cross-plane $1.5D$ downstream of the sphere position reveal that the sphere wake consists of vortex loops, similar to the wake of a sphere without any imposed rotation; however, there is a change in the timing of vortex formation. On the other hand, for high $f_{R}$ values, there is a reduction in the streamwise vorticity, presumably leading to a decreased total transverse force acting on the sphere and resulting in a reduced response.

The present experimental investigation characterises the dynamic response and wake structure of a sinusoidally rotating circular cylinder with a low mass ratio (defined as the ratio of the total oscillating mass to the displaced fluid mass) undergoing cross-stream flow-induced vibration (FIV). The study covers a wide parameter space spanning the forcing rotary oscillation frequency ratio $0\leqslant f_{r}^{\ast }\leqslant 4.5$ and the forcing rotation speed ratio $0\leqslant \unicode[STIX]{x1D6FC}_{r}^{\ast }\leqslant 2.0$ , at reduced velocities associated with the vortex-induced vibration (VIV) upper and lower amplitude response branches. Here, $f_{r}^{\ast }=f_{r}/f_{nw}$ and $\unicode[STIX]{x1D6FC}_{r}^{\ast }=\unicode[STIX]{x1D6FA}_{o}D/(2U)$ , where $f_{r}$ is the forcing rotary oscillation frequency, $f_{nw}$ is the natural frequency of the system in quiescent fluid (water), $\unicode[STIX]{x1D6FA}_{o}$ is the peak angular rotation speed, $D$ is the cylinder diameter and $U$ is the free-stream velocity; the reduced velocity is defined by $U^{\ast }=U/(\,f_{nw}D)$ . The fluid–structure system was modelled using a low-friction air-bearing system in conjunction with a free-surface recirculating water channel, with axial rotary motion provided by a microstepping motor. The cylinder was allowed to vibrate with only one degree of freedom transverse to the oncoming free-stream flow. It was found that in specific ranges of $f_{r}^{\ast }$ , the body vibration frequency may deviate from that seen in the non-rotating case and lock onto the forcing rotary oscillation frequency or its one-third subharmonic. The former is referred to as the ‘rotary lock-on’ (RLO) region and the latter as the ‘tertiary lock-on’ (TLO) region. Significant increases in the vibration amplitude and suppression of VIV could both be observed in different parts of the RLO and TLO regions. The peak amplitude response in the case of $U^{\ast }=5.5$ (upper branch) was observed to be $1.2D$ , an increase of approximately $50\,\%$ over the non-rotating case, while in the case of $U^{\ast }=8.0$ (lower branch), the peak amplitude response was $2.2D$ , a remarkable increase of $270\,\%$ over the non-rotating case. Notably, the results showed that the amplitude responses at moderate Reynolds numbers ($Re=UD/\unicode[STIX]{x1D708}=2060$ and $2940$ , where $\unicode[STIX]{x1D708}$ is the kinematic viscosity of the fluid) in the present study showed significant differences from those of a previous low-Reynolds-number ($Re=350$ ) numerical study at similar reduced velocities by Du & Sun (Phys. Fluids, vol. 14 (8), 2015, pp. 2767–2777). Remarkably, in an additional study examining the cylinder vibration as a function of $U^{\ast }$ while the fixed forcing rotary oscillation parameters were kept constant at $(f_{r}^{\ast },\unicode[STIX]{x1D6FC}_{r}^{\ast })=(1.0,1.0)$ , the cylinder experienced substantially larger oscillations than in the non-rotating case, and a rotation-induced galloping response was observed for $U^{\ast }>12$ , where the amplitude increased monotonically to reach approximately $3.0D$ at the highest reduced velocity ($U^{\ast }=20$ ) tested. Furthermore, new wake modes were identified in the RLO and TLO regions using particle image velocimetry measurements at selected points in the $f_{r}^{\ast }-\unicode[STIX]{x1D6FC}_{r}^{\ast }$ parameter space.

This study experimentally investigates the in-line flow-induced vibration (FIV) of an elastically mounted circular cylinder under forced axial rotation in a free stream. The present experiments characterise the structural vibration, fluid forces and wake structure of the fluid–structure system at a low mass ratio (the ratio of the total mass to the displaced fluid mass) over a wide parameter space spanning the reduced velocity range $5\leqslant U^{\ast }\leqslant 32$ and the rotation rate range $0\leqslant \unicode[STIX]{x1D6FC}\leqslant 3.5$ , where $U^{\ast }=U/(\,f_{nw}D)$ and $\unicode[STIX]{x1D6FC}=|\unicode[STIX]{x1D6FA}|D/(2U)$ , with $U$ the free-stream velocity, $D$ the cylinder outer diameter, $f_{nw}$ the natural frequency of the system in quiescent water and $|\unicode[STIX]{x1D6FA}|$ the angular velocity of the cylinder rotation. The corresponding Reynolds number (defined by $Re=UD/\unicode[STIX]{x1D708}$ , with $\unicode[STIX]{x1D708}$ the kinematic viscosity of the fluid) was varied over the interval $1349\leqslant Re\leqslant 8624$ , where it is expected that the FIV response is likely to be relatively insensitive to the Reynolds number. The fluid–structure system was modelled using a low-friction air-bearing system in conjunction with a free-surface water-channel facility. Three vibration regions that exhibited vortex-induced vibration (VIV) synchronisation, rotation-induced galloping and desynchronised responses were observed. In both the VIV synchronisation and rotation-induced galloping regions, significant cylinder vibration was found to be correlated with wake–body synchronisation within the rotation rate range $2.20\lesssim \unicode[STIX]{x1D6FC}\lesssim 3.15$ . Of significant interest, the frequency of the streamwise fluid force could be modulated by the imposed rotation to match that of the transverse lift force, resulting in harmonic synchronisation. Measurements using the particle image velocimetry (PIV) technique were performed to identify the wake structure. Interestingly, the imposed rotation can cause regular vortex shedding in in-line FIV at rotation rates that see suppression of the Bénard–von-Kármán vortex shedding in the case of a rigidly mounted cylinder ($\unicode[STIX]{x1D6FC}\gtrsim 1.75$ ). There is a monotonic increase in the drag coefficient with rotation rate beyond $\unicode[STIX]{x1D6FC}=2$ for a non-oscillating rotating cylinder. This suggests that the mechanism for sustaining the large rotation-induced galloping oscillations at higher $\unicode[STIX]{x1D6FC}$ is due to a combination of aerodynamic forcing from the locked induced vortex shedding associated with the oscillations, assisted by aerodynamic forcing, evaluated using quasi-steady theory.

Results are presented from an experimental investigation into the effects of proximity to a free surface on vortex-induced vibration (VIV) experienced by fully and semi-submerged spheres that are free to oscillate in the cross-flow direction. The VIV response is studied over a wide range of reduced velocities: $3\leqslant U^{\ast }\leqslant 20$ , covering the mode I, mode II and mode III resonant response branches and corresponding to the Reynolds number range of $5000\lesssim Re\lesssim 30\,000$ . The normalised immersion depth of the sphere is varied in small increments over the range $0\leqslant h^{\ast }\leqslant 1$ for the fully submerged case and $0\leqslant h^{\ast }\leqslant -0.75$ for the semi-submerged case. It is found that for a fully submerged sphere, the vibration amplitude decreases monotonically and gradually as the immersion ratio is decreased progressively, with a greater influence on the mode II and III parts of the response curve. The synchronisation regime becomes narrower as $h^{\ast }$  is decreased, with the peak saturation amplitude occurring at progressively lower reduced velocities. The peak response amplitude decreases almost linearly over the range of $0.5\leqslant h^{\ast }\leqslant 0.185$ , beyond which the peak response starts increasing almost linearly. The trends in the total phase, $\unicode[STIX]{x1D719}_{total}$ , and the vortex phase, $\unicode[STIX]{x1D719}_{vortex}$ , reveal that the mode II response occurs for progressively lower $U^{\ast }$ values with decreasing $h^{\ast }$ . On the other hand, when the sphere pierces the free surface, there are two regimes with different characteristic responses. In regime $\text{I}$ ($-0.5<h^{\ast }<0$ ), the synchronisation region widens and the vibration amplitude increases, surprisingly becoming even higher than for the fully submerged case in some cases, as $h^{\ast }$ decreases. However, in regime $\text{II}$ ($-0.5\leqslant h^{\ast }\leqslant -0.75$ ), the vibration amplitude decreases with a decrease in $h^{\ast }$ , showing a very sharp reduction beyond $h^{\ast }<-0.65$ . The response in regime II is characterised by two distinct peaks in the amplitude response curve. Careful analysis of the force data and phase information reveals that the two peaks correspond to modes I and II seen for the fully submerged vibration response. This two-peak behaviour is different to the classic VIV response of a sphere under one degree of freedom (1-DOF). The response was found to be insensitive to the Froude number ($Fr=U/\sqrt{gD}$ , where $U$ is the free-stream velocity, $D$ is the sphere diameter and $g$ is the acceleration due to gravity) in the current range of $0.05\leqslant Fr\leqslant 0.45$ , although higher Froude numbers resulted in slightly lower peak response amplitudes. The wake measurements in the cross-plane $1.5D$ downstream of the rear of the sphere reveal a reduction in the vorticity of the upper vortex of the trailing vortex pair, presumably through diffusion of vorticity into the free surface. For the piercing sphere case, the near-surface vorticity completely diffuses into the free surface, with only the opposite-signed vortex visible in the cross-plane at this downstream position. Interestingly, this correlates with an even higher oscillation amplitude than the fully submerged case. Finally, the effects of immersion ratio and diameter ratio ($D^{\ast }$  $=$  sphere diameter/support-rod diameter) are quantified, showing care needs to be taken with these factors to avoid unduly influencing VIV predictions.