Weak Feedback Research Articles

Slow Modes of Global Temperature Variability and Their Impact on Climate Sensitivity Estimates

AbstractInternal climate variability confounds estimates of the climate response to forcing but offers an opportunity to examine the dynamics controlling Earth’s energy budget. This study analyzes the time-evolving impact of modes of low-frequency internal variability on global-mean surface temperature (GMST) and top-of-atmosphere (TOA) radiation in preindustrial control simulations from phase 6 of the Coupled Model Intercomparison Project (CMIP6). The results show that the slow modes of variability with the largest impact on decadal GMST anomalies are focused in high-latitude ocean regions, where they have a minimal impact on global TOA radiation. When these regions warm, positive shortwave cloud and sea ice–albedo feedbacks largely cancel the negative feedback of outgoing longwave radiation, resulting in a weak net radiative feedback. As a consequence of the weak net radiative feedback, less energy is required to sustain these long-lived temperature anomalies. In contrast to these weakly radiating high-latitude modes, El Niño–Southern Oscillation (ENSO) has a large impact on the global energy budget, such that it remains the dominant influence on global TOA radiation out to decadal and longer time scales, despite its primarily interannual time scale. These results show that on decadal and longer time scales, different processes control internal variability in GMST than control internal variability in global TOA radiation. The results are used to quantify the impact of low-frequency internal variability and ENSO on estimates of climate sensitivity from historical GMST and TOA-radiative-imbalance anomalies.

ESD Ideas: A weak positive feedback between sea level and the planetary albedo

Abstract. Since the planetary albedo of Earth above ocean is typically lower than above land surface, increasing sea level reduces the planetary albedo. This causes a feedback that is very weak on the global scale, but significantly positive. Its amplitude can be assumed to be higher locally and to grow with the considered timescale.

Exploring women's development group leaders' support to maternal, neonatal and child health care: A qualitative study in Tigray region, Ethiopia.

Community health workers and volunteers are vital for the achievement of Universal Health Coverage also in low-income countries. Ethiopia introduced community volunteers called women's development group leaders in 2011. These women have responsibilities in multiple sectors, including promoting health and healthcare seeking. We aimed to explore women's development group leaders' and health workers' perceptions on these volunteers' role in maternal, neonatal and child healthcare. A qualitative study was conducted with in-depth interviews and focus group discussions with women's development group leaders, health extension workers, health center staff, and woreda and regional health extension experts. We adapted a framework of community health worker performance, and explored perceptions of the women's development group program: inputs, processes and performance. Interviews were recorded, transcribed, and coded prior to translation and thematic analysis. The women's development group leaders were committed to their health-related work. However, many were illiterate, recruited in a sub-optimal process, had weak supervision and feedback, lacked training and incentives and had weak knowledge on danger signs and care of neonates. These problems demotivated these volunteers from engaging in maternal, neonatal and child health promotion activities. Health extension workers faced difficulties in managing the numerous women's development group leaders in the catchment area. The women's development group leaders showed a willingness to contribute to maternal and child healthcare but lacked support and incentives. The program requires some redesign, effective management, and should offer enhanced recruitment, training, supervision, and incentives. The program should also consider continued training to develop the leaders' knowledge, factor contextual influences, and be open for local variations.

Niño 4 West (Niño‐4W) Sea Surface Temperature Variability

AbstractSea surface temperature (SST) variability in the western half of the Niño 4 region (Niño‐4W), bounded by 160°E−175°W and 5°S–5°N, has a significant impact on weather and the marine environment of the Indo‐Pacific. It exhibits significant negative skewness, with the strong penetration of the cold tongue into the western Pacific during strong La Niñas but a more muted response during El Niños. Zonal advection plays a dominant role in driving Niño‐4W SST cooling during the strong La Niña events; vertical processes also contribute, with air‐sea heat fluxes providing weak negative feedback. Advection also plays a key role in driving the Niño‐4W SST warming, which is not always in sync with El Niño events. Among the advection terms, the advection of mean temperature by zonal velocity anomalies, or zonal advective feedback, plays a key role during the development phase of the warm and cold events. Strong negative air‐sea heat flux anomalies during the development of warm events are linked to the negative SST skewness in the Niño‐4W region.

Plant-soil feedbacks depend on drought stress, functional group, and evolutionary relatedness in a semiarid grassland.

Plant-soil feedback (PSF) occurs when plants change the biota and physicochemical properties of the soil, and these changes affect future survival or growth of plants. PSF depends on several factors such as plant functional attributes (e.g., life cycle or photosynthetic metabolism) and the environment. PSF often turn positive under dry conditions because soil biota confers drought tolerance. Conspecifics and close relatives share pathogens and consume similar resources, exerting negative PSF on each other. These ideas have mostly been tested under controlled conditions, while field studies remain scarce. To reevaluate these findings in nature, we analyzed plant-soil feedbacks over a drought-stress gradient in a phosphorus-limited semiarid grassland. We planted seedlings of 17 species in plots where community composition had been monitored for six years. To determine PSF intensity, we measured how seedling longevity was affected by previous occupancy of conspecifics and heterospecifics. The previous occupancy-survival relationship (OSR) was used as a proxy for PSF. Evidence for OSRs was found in one-third of the species pairs, with inconclusive evidence for the rest suggesting weak feedbacks. This is in line with the expectation that PSFs in the field are weaker than under controlled conditions. As expected, positive PSFs were more frequent as drought stress increased. The strongest OSRs were caused in dry plots by C4 perennial grasses, which had very positive OSRs on several C3 annual forbs, but negative effects on each other. Well-documented differences between these two functional groups may explain this result: C3 plants are more sensitive to drought, and thus may be favored by tolerance-conferring microbiota; in contrast, water-efficient C4 perennial grasses compete for phosphorus strongly, perhaps driving strong negative PSFs between them. Finally, close relatives had more negative OSRs on each other than on distant relatives as expected, although only in dry plots. This pattern was mostly due to the negative effects of closely related C4 grasses under dry conditions, and their positive effects on distantly related dicots. Our results highlight the importance of plant traits and of the environmental context in determining the direction and strength of PSFs under field conditions.

Collision-induced formation of dark-matter-deficient galaxies

AbstractThe standard galaxy formation model predicts that galaxies form within a Cold Dark Matter (CDM) halo and that galaxies are dominated by dark matter. However, recent observations have discovered dark-matter-deficient galaxies with much less dark matter mass than theoretical predictions, and the process of their formation has been discussed. Here, we investigate the physical processes of galaxy formation by collisions between gas-rich dark matter subhalos within the context of the CDM paradigm. We investigate the formation process of dark-matter-deficient galaxies by running three-dimensional simulations of the collision process between dark matter subhalos (DMSHs) with the same mass of 109M⊙ colliding the velocity of 100 km s−1. We then compared the effect of different supernova feedback models, the subgrid physics of the simulation, on the collision-induced formation of galaxies. The results show that the strong feedback model ejects gas out of the system more efficiently than the weak feedback model, leading to lower star formation rates and the formation of a more extended galaxy. Finally, dark-matter-deficient galaxies with stellar masses of ∼ 107M⊙ and ∼ 108M⊙ are formed in the weak and strong feedback models, respectively.

Feedback Sensitivity of DBR-Type Laser Diodes

It is shown theoretically that the feedback sensitivity of Distributed Bragg Reflector laser diodes with low-loss Bragg section decreases with the length of the Bragg section and also can be decreased by detuning from the Bragg peak. The effect of detuning is not only due to a change in effective linewidth enhancement factor, but also due to a change of the effective cavity length. The results can be applied also to laser diodes coupled on one side to one or more ring resonators Such lasers can have very weak feedback sensitivity.

Relationship between metabolic syndrome components in patients with resistant arterial hypertension

Metabolic syndrome (MS) is a complex of interrelated pathological conditions based on insulin resistance, obesity, dyslipoproteinemia, arterial hypertension (AH). MS is a predictor of the cardiovascular disease, type 2 diabetes mellitus (DM), cancer and premature death. The incidence of type 2 diabetes increases with age and is 25.2% among the elderly. The prevalence of prediabetes or metabolic syndrome was approximately three times higher. Heart failure is another important cause of morbidity and mortality from the cardiovascular disease. Recent studies have shown that the incidence of hospitalizations for heart failure (adjusted for age and gender) was twice as high in patients with diabetes compared with patients without diabetes. Patients with hypertension and abdominal obesity (AO) have an increased risk of various complications: type 2 diabetes -5-9 times, stroke - 7 times, coronary heart disease - 4 times and mortality - 2 times. Objective: To analyze the relationship between the components of the metabolic syndrome in patients with resistant arterial hypertension (RAH). Materials and methods. A retrospective analysis of case histories of 120 patients, including 52 men (43.33%) and 68 women (56.67%) with a diagnosis of RAH and signs of MS. The presence of concomitant pathology, the level of office arterial pressure, pulse pressure (PP) were calculated; body weight, height with calculation of body mass index (BMI); waist circumference (WC), the levels of low-density lipoprotein (LDL) and high-density lipoprotein (HDL), triglycerides (TG), and plasma glucose were studied. Student's criterion was used to assess the degree of significance of the differences, p≤0.05 was taken as the critical level of significance. Pearson's correlation coefficient was used. Disorders of carbohydrate metabolism among patients with MS and RAH is 67.50%, of which type 2 diabetes makes 50.83%, impaired glucose tolerance - 16.67%. Patients with impaired carbohydrate metabolism are 2 times more likely to have complications of hypertension and lower HDL. Women with MS and RAH were significantly older than men and more often had concomitant pathology: morbid obesity (p <0.05), type 2 diabetes mellitus (p <0.05), chronic cerebral ischemia (p <0.05), higher body mass index (p <0.01). Strong correlation between WC and BMI (r = 0.707; p˂0.001), weak direct correlations between WC and PP (r = 0.231; p˂0.05) and WC and TG (r = 0.221; p˂0.05), weak feedback between WC and age (r = -0.188; p˂0.05), and for men direct correlations between WC and TG were confirmed (r = 0.454; p˂0.001), BMI and TG (r = 0.454, p˂0.002).

Stochastic bursting in networks of excitable units with delayed coupling

We investigate the phenomenon of stochastic bursting in a noisy excitable unit with multiple weak delay feedbacks, by virtue of a directed tree lattice model. We find statistical properties of the appearing sequence of spikes and expressions for the power spectral density. This simple model is extended to a network of three units with delayed coupling of a star type. We find the power spectral density of each unit and the cross-spectral density between any two units. The basic assumptions behind the analytical approach are the separation of timescales, allowing for a description of the spike train as a point process, and weakness of coupling, allowing for a representation of the action of overlapped spikes via the sum of the one-spike excitation probabilities.

Frequency stabilization of a quantum cascade laser by weak resonant feedback from a Fabry-Perot cavity.

Frequency-stabilized mid-infrared lasers are valuable tools for precision molecular spectroscopy. However, their implementation remains limited by complicated stabilization schemes. Here we achieve optical self-locking of a quantum cascade laser to the resonant leak-out field of a highly mode-matched two-mirror cavity. The result is a simple approach to achieving stable frequencies from high-powered mid-infrared lasers. For short time scales (<0.1ms), we report a linewidth reduction factor of 3×10-6 to a linewidth of 12 Hz. Furthermore, we demonstrate two-photon cavity-enhanced absorption spectroscopy of an N2O overtone transition near a wavelength of 4.53 µm.

High-resolution LAsMA 12CO and 13CO observation of the G305 giant molecular cloud complex

Context. Understanding the effect of feedback, interaction of young massive stars with their parental giant molecular clouds, is of central importance for studies of the interstellar medium and star formation. Aims. We observed the G305 star-forming complex in the J = 3–2 lines of 12CO and 13CO to investigate how molecular gas surrounding the central stellar clusters is being impacted by feedback. Methods. The Atacama Pathfinder EXperiment (APEX) telescope’s Large APEX sub-Millimeter Array (LAsMA) multibeam receiver was used to observe the region. Excitation temperatures and column density maps were produced. Combining our data with data from the structure, excitation, and dynamics of the inner Galactic interstellar medium survey resulted in a 13CO J = 3−2∕2−1 excitation map. To verify whether feedback from stellar clusters is responsible for exciting the gas, the distribution of CO excitation was compared with that of 8 μm emission imaged with Spitzer, which is dominated by UV-excited emission from polycyclic aromatic hydrocarbons. Line centroid velocities, as well as stacked line profiles were examined to investigate the effect of feedback on the gas dynamics. Results. Line profiles along radially outward directions demonstrate that the excitation temperature and 13CO J = 3−2∕2−1 ratio increase steeply by factors of ~2–3 at the edge of the denser gas traced by 13CO that faces the hot stars at the center of the complex and steadily decreases away from it. The column density also increases at the leading edge, but it does not always decrease steadily outward. Regions with a higher 8 μm flux have higher median excitation temperatures, column densities, and 13CO J = 3−2∕2−1 ratio. The centroid velocity probability distribution function of the region shows exponential wings, indicative of turbulence driven by strong stellar winds. Stacked spectra in regions with stronger feedback have higher skewness and narrower peaks with pronounced wings compared to regions with weaker feedback. Conclusions. Feedback from the stellar cluster in G305 has demonstrable effects on the excitation as well as on the dynamics of the giant molecular cloud.

Terahertz near-field nanoscopy based on detectorless laser feedback interferometry under different feedback regimes

Near-field imaging techniques, at terahertz frequencies (1–10 THz), conventionally rely on bulky laser sources and detectors. Here, we employ a semiconductor heterostructure laser as a THz source and, simultaneously, as a phase-sensitive detector, exploiting optical feedback interferometry combined with scattering near-field nanoscopy. We analyze the amplitude and phase sensitivity of the proposed technique as a function of the laser driving current and of the feedback attenuation, discussing the operational conditions ideal to optimize the nano-imaging contrast and the phase sensitivity. As a targeted nanomaterial, we exploit a thin (39 nm) flake of Bi2Te2.2Se0.8, a topological insulator having infrared active optical phonon modes. The self-mixing interference fringes are analyzed within the Lang–Kobayashi formalism to rationalize the observed variations as a function of Acket’s parameter C in the full range of weak feedback (C &amp;lt; 1).

The role of gas fraction and feedback in the stability and evolution of galactic discs: implications for cosmological galaxy formation models

ABSTRACT High-redshift star-forming galaxies often have irregular morphologies with giant clumps containing up to 108−109 solar masses of gas and stars. The origin and evolution of giant clumps are debated both theoretically and observationally. In most cosmological simulations, high-redshift galaxies have regular spiral structures or short-lived clumps, in contradiction with many idealized high-redshift disc models. Here, we test whether this discrepancy can be explained by the low gas fractions of galaxies in cosmological simulations. We present a series of simulations with varying gas fractions, from 25 per cent, typical of galaxies in most cosmological simulations, to 50 per cent, typical of observed galaxies at 1.5 &amp;lt; z &amp;lt; 3. We find that gas-poor models have short-lived clumps, that are unbound and mostly destroyed by galactic shear, even with weak stellar feedback. In contrast, gas-rich models form long-lived clumps even with boosted stellar feedback. This shows that the gas mass fraction is the primary physical parameter driving violent disc instabilities and the evolution of giant clumps on ∼108 yr time-scales, with lower impact from the calibration of the stellar feedback. Many cosmological simulations of galaxy formation have relatively gas-poor galactic discs, which could explain why giant clumps are absent or short-lived in such models. Similar baryonic and dark matter mass distribution could produce clumpy galaxies with long-lived clumps at z ∼ 2 if the gas fraction was in better agreement with observations.

Life cycle sustainability assessment of a light rail transit system: Integration of environmental, economic, and social impacts.

The transition towardsustainable urban transportation has gained importance in recent decades. However, urban transportation has not been addressed for all dimensions of sustainability. This study presents a life cycle sustainability assessment of a light rail transit system in Kayseri, Turkey, by integrating environmental, economic, and social aspects. The sustainability performance of the light rail transit system is evaluated using a cradle-to-grave approach to assess three aspects of sustainability. For the environmental evaluation, a life cycle assessment was applied using SimaPro 8.4.1 PhD version based on ISO 14040 and 14044. The method, which includes nine environmental impact categories, was employed to assess the environmental performance of the light rail transit system with a functional unit of 1 passenger-km. For the economic assessment, life cycle costing was utilized with the functional unit of USD for 1 passenger-km. A social life cycle assessment was applied to assess the social performance of the light rail transit system based on guidelines published by the United Nations Environment Programme in collaboration with the Society of Environmental Toxicology and Chemistry. For the determination of social impacts, 11 subcategories and 18 social indicators were selected. The results showed that the global warming potential and abiotic depletion potential of the light rail system per passenger-km were 2.4E - 02 kg CO2 eq. and 2.7E - 01 MJ, respectively, with a service life of 50 years. The total life cycle cost of the light rail system was calculated as 0.046 USD for 1 passenger-km. The results also revealed that the main contributor to the total life cycle cost was energy cost, with 92% (2.88E + 08 USD) of the total cost. In the social performance evaluation, it is found that the industry performs well for society, the local community, and workers but has a weaker social performance for the consumer due to a weak feedback mechanism. Integr Environ Assess Manag 2021;17:1070-1082. © 2021 SETAC.

The resilience of Amazon tree cover to past and present drying

The Amazon forest is increasingly vulnerable to dieback and encroachment of grasslands and agricultural fields. Threats to these forested ecosystems include drying, deforestation, and fire, but feedbacks among these make it difficult to determine their relative importance. Here, we reconstruct the central and western Amazon tree cover response to aridity and fire in the mid-Holocene—a time of less intensive human land use and markedly drier conditions than today—to assess the resilience of tree cover to drying and the strength of vegetation-climate feedbacks. We use pollen, charcoal, and speleothem oxygen isotope proxy data to show that Amazon tree cover in the mid-Holocene was resilient to drying in excess of the driest bias-corrected future precipitation projections. Experiments with a dynamic global vegetation model (LPJ-GUESS) suggest tree cover resilience may be owed to weak feedbacks that act to amplify tree cover loss with drying. We also compare these results to observational data and find that, under limited human interference, modern tree cover is likely similarly resilient to mid-Holocene levels of aridification. Our results suggest human-driven fire and deforestation likely pose a greater threat to the future of Amazon ecosystems than drying alone.

Observational constraints on low cloud feedback reduce uncertainty of climate sensitivity

Marine low clouds strongly cool the planet. How this cooling effect will respond to climate change is a leading source of uncertainty in climate sensitivity, the planetary warming resulting from CO2 doubling. Here, we observationally constrain this low cloud feedback at a near-global scale. Satellite observations are used to estimate the sensitivity of low clouds to interannual meteorological perturbations. Combined with model predictions of meteorological changes under greenhouse warming, this permits quantification of spatially resolved cloud feedbacks. We predict positive feedbacks from midlatitude low clouds and eastern ocean stratocumulus, nearly unchanged trade cumulus and a near-global marine low cloud feedback of 0.19 ± 0.12 W m−2 K−1 (90% confidence). These constraints imply a moderate climate sensitivity (~3 K). Despite improved midlatitude cloud feedback simulation by several current-generation climate models, their erroneously positive trade cumulus feedbacks produce unrealistically high climate sensitivities. Conversely, models simulating erroneously weak low cloud feedbacks produce unrealistically low climate sensitivities.

SEAGLE – II. Constraints on feedback models in galaxy formation from massive early-type strong-lens galaxies

ABSTRACT We use nine different galaxy formation scenarios in ten cosmological simulation boxes from the EAGLE (Evolution and Assembly of GaLaxies and their Environments) suite of Lambda cold dark matter hydrodynamical simulations to assess the impact of feedback mechanisms in galaxy formation and compare these to observed strong gravitational lenses. To compare observations with simulations, we create strong lenses with M* &amp;gt; 1011 M⊙ with the appropriate resolution and noise level, and model them with an elliptical power-law mass model to constrain their total mass density slope. We also obtain the mass–size relation of the simulated lens-galaxy sample. We find significant variation in the total mass density slope at the Einstein radius and in the projected stellar mass–size relation, mainly due to different implementations of stellar and active galactic nucleus (AGN) feedback. We find that for lens-selected galaxies, models with either too weak or too strong stellar and/or AGN feedback fail to explain the distribution of observed mass density slopes, with the counter-intuitive trend that increasing the feedback steepens the mass density slope around the Einstein radius (≈3–10 kpc). Models in which stellar feedback becomes inefficient at high gas densities, or weaker AGN feedback with a higher duty cycle, produce strong lenses with total mass density slopes close to isothermal [i.e. −dlog (ρ)/dlog (r) ≈ 2.0] and slope distributions statistically agreeing with observed strong-lens galaxies in Sloan Lens ACS Survey and BOSS (Baryon Oscillation Spectroscopic Survey) Emission-Line Lens Survey. Agreement is only slightly worse with the more heterogeneous Strong Lensing Legacy Survey lens-galaxy sample. Observations of strong-lens-selected galaxies thus appear to favour models with relatively weak feedback in massive galaxies.

Coherent laser detection of the femtowatt-level frequency-shifted optical feedback based on a DFB fiber laser.

The theoretical basis and experimental realization of an all-fiber self-mixing laser Doppler velocimetry based on frequency-shifted feedback in a distributed feedback (DFB) fiber laser are presented, which employs a pair of fiber-coupled acousto-optic modulators to adjust the modulation intensity and frequency of the laser self-mixing effect. Moreover, the minimum optical feedback intensity for the velocity signal successfully measured by the interferometer is 5.12 fW, corresponding to 0.16 photons per Doppler cycle. The results demonstrate that the proposed scheme can adapt to the non-contact measurement requirements of the wide-range speed and weak feedback level in the complex environment.

Evaluation of Measles Surveillance Systems in Ginnir District, Bale Zone, Southeast Ethiopia: A Concurrent Embedded Mixed Quantitative/Qualitative Study.

BackgroundPublic health surveillance systems should be evaluated periodically to ensure the problems of public health importance are being monitored efficiently and effectively. Despite the widespread measles outbreak in Ginnir district of Ethiopia in 2019, an evaluation of measles surveillance systems has not been conducted. Therefore, we evaluated the performance of measles surveillance systems and key attributes in Ginnir district, Southeast Ethiopia.MethodsWe conducted a concurrent embedded mixed quantitative/qualitative study in August 2019 among 15 health facilities/study units in Ginnir district. The qualitative study involved a purposively selected 15 key-informants. Data were collected using updated guidelines for evaluating surveillance systems based on CDC’s Framework.ResultsRecords of 15 study units were reviewed and 15 key informants participated. The structure of surveillance data flow was from the community to the respective upper level. Emergency preparedness and a response plan was available only at the district level. Weekly report completeness and timeliness were 95% and 87% respectively. We found weak supportive supervision and feedback, and no regular analysis and interpretations of surveillance data. The participation of surveillance stakeholders in implementation of the system was good. The surveillance system was found to be useful, easy to implement, representative, and can accommodate and adapt to changing operating conditions. Report documentation and quality of data was poor at lower level health facilities. The stability of the system has been challenged by a shortage of budget, logistics, staff turnover and lack of update trainings.ConclusionThe surveillance system was acceptable, useful, simple, flexible, and representative. Quality of data, timeliness, and the stability of the system were attributes that require improvement. The overall performance of measles surveillance systems in prevention and control of measles was weak. Hence, regular analysis of data, preparation, and dissemination of epidemiological bulletin, capacity building, and regular supervision and feedback are recommended to enhance performance of the system.

A Cuspy Dark Matter Halo

Abstract The cusp–core problem is one of the main challenges of the cold dark matter paradigm on small scales; the density of a dark matter halo is predicted to rise rapidly toward the center as ρ(r) ∝ r α with α between −1 and −1.5, while such a cuspy profile has not been clearly observed. We have carried out the spatially resolved mapping of gas dynamics toward a nearby ultradiffuse galaxy (UDG), AGC 242019. The derived rotation curve of dark matter is well fitted by the cuspy profile as described by the Navarro–Frenk–White model, while the cored profiles including both the pseudo-isothermal and Burkert models are excluded. The halo has α = −(0.90 ± 0.08) at the innermost radius of 0.67 kpc, M halo = (3.5 ± 1.2) × 1010 M ⊙, and a small concentration of 2.0 ± 0.36. The UDG AGC 242019 challenges alternatives of cold dark matter by constraining the particle mass of fuzzy dark matter to be &lt;0.11 × 10−22 or &gt;3.3 × 10−22 eV, the cross section of self-interacting dark matter to be &lt;1.63 cm2 g−1, and the particle mass of warm dark matter to be &gt;0.23 keV, all of which are in tension with other constraints. The modified Newtonian dynamics is also inconsistent with a shallow radial acceleration relationship of AGC 242019. For the feedback scenario that transforms a cusp to a core, AGC 242019 disagrees with the stellar-to-halo mass ratio dependent model but agrees with the star formation threshold dependent model. As a UDG, AGC 242019 is in a dwarf-sized halo with weak stellar feedback, late formation time, normal baryonic spin, and low star formation efficiency (SFR/gas).