Miracle-dz/UniFAR-FTUs huggingface dataset:
Stability and Convergence Trade-off of Iterative Optimization Algorithms

The overall performance or expected excess risk of an iterative machine learning algorithm can be decomposed into training error and generalization error. While the former is controlled by its convergence analysis, the latter can be tightly handled by algorithmic stability. The machine learning community has a rich history investigating convergence and stability separately. However, the question about the trade-off between these two quantities remains open. In this paper, we show that for any iterative algorithm at any iteration, the overall performance is lower bounded by the minimax statistical error over an appropriately chosen loss function class. This implies an important trade-off between convergence and stability of the algorithm -- a faster converging algorithm has to be less stable, and vice versa. As a direct consequence of this fundamental tradeoff, new convergence lower bounds can be derived for classes of algorithms constrained with different stability bounds. In particular, when the loss function is convex (or strongly convex) and smooth, we discuss the stability upper bounds of gradient descent (GD) and stochastic gradient descent and their variants with decreasing step sizes. For Nesterov's accelerated gradient descent (NAG) and heavy ball method (HB), we provide stability upper bounds for the quadratic loss function. Applying existing stability upper bounds for the gradient methods in our trade-off framework, we obtain lower bounds matching the well-established convergence upper bounds up to constants for these algorithms and conjecture similar lower bounds for NAG and HB. Finally, we numerically demonstrate the tightness of our stability bounds in terms of exponents in the rate and also illustrate via a simulated logistic regression problem that our stability bounds reflect the generalization errors better than the simple uniform convergence bounds for GD and NAG.
Production of L-lactic acid from starch and food waste by amylolytic Rhizopus oryzae MTCC 8784.

Lactic acid, commonly used in food, chemical and pharmaceutical industries, has recently received much attention for the production of biodegradable plastics. In this study, Rhizopus oryzae MTCC 8784 was used to convert starch into optically pure L-Lactic acid. Effect of time, pH, addition of calcium car bonate and starch concentration were analyzed using shaker fla sks in order optimize the L-lactic acid concentrati on and volumetric productivity. Under optimized conditions (pH6.0, CaCO 3 (10g/L), starch (10g/L) and 72 h of cultivation) R.oryzae MTCC 8784 gave a lactic acid concentration of 50.48g /L with a volumetric productivity (Q p) of 0.7 (g/L/h) and lactic acid yield(Y P/s) of 4.54 g/g (2 fold increase), 100% starch sacchar ification, and 1.5 g/L mycelial biomass. To reduce the Lactic acid pro duction costs, inexpensive raw materials such as fo od waste (fruit and vegetable peel/waste) like sapota, banan a, papaya, potato, corn cob and carboxymethyl cellu lose were explored. All substrates tested supported growth a nd lactic acid production. Efficient lactic acid co ncentration (72g/L) with a biomass of 1.9 g/L; volumetric produ ctivity (Q p) of 1g/L/h and lactic acid yield(Y P/s) of 3.6g/g was obtained with sapota peel fermentation. Lactic acid was detected in the fermentation broth by HPLC.
Structure and organization of a northern New England salt marsh plant community

1 Northern New England marshes are characterized by mid‐elevation areas of sparse vegetation, but high species diversity, which are not found in the well‐studied marshes further south. These forb pannes occur in habitats that are more waterlogged and anoxic than adjacent clonal turf‐dominated areas. 2 When the clonal turfs were transplanted into forb pannes, they showed reduced growth with and without neighbours present, suggesting that they are physically limited from invading the forb pannes. Conversely, when forb panne species were transplanted into surrounding turf areas, they flourished when neighbours were removed, but were suppressed when neighbours were present, suggesting that interspecific plant competition restricts the forbs to panne habitats. 3 Recovery of disturbance‐generated bare patches was extremely slow, taking twice as long as in southern New England marshes. Secondary succession in northern New England marshes was driven by competitive interactions rather than by facilitative processes typical in southern New England marshes. 4 Differences in the structure and dynamics between northern and southern New England marsh systems may be due to differences in climate and human impacts. Waterlogged pannes are probably more common in northern marshes because they are generally larger and less ditched and drained. Reduced solar radiation and summer heating in northern New England reduces the potential for high soil salinities seen in southern marshes. This lack of the need for amelioration by neighbours probably explains the absence of facilitation.
Human tracking and segmentation supported by silhouette-based gait recognition

Gait recognition has recently gained attention as an effective approach to identify individuals at a distance from a camera. Most existing gait recognition algorithms assume that people have been tracked and silhouettes have been segmented successfully. Tacking and segmentation are, however, very difficult especially for articulated objects such as human beings. Therefore, we present an integrated algorithm for tracking and segmentation supported by gait recognition. After the tracking module produces initial results consisting of bounding boxes and foreground likelihood images, the gait recognition module searches for the optimal silhouette-based gait models corresponding to the results. Then, the segmentation module tries to segment people out using the provided gait silhouette sequence as shape priors. Experiments on real video sequences show the effectiveness of the proposed approach.
Anterior cruciate ligament tears treated with percutaneous injection of autologous bone marrow nucleated cells: a case series

Introduction This was a prospective case series designed to investigate treatment for anterior cruciate ligament (ACL) tears using an injection of autologous bone marrow concentrate. Methods Consecutive adult patients presenting to a private outpatient interventional musculoskeletal and pain practice with knee pain, ACL laxity on exam, and magnetic resonance imaging (MRI) evidence of a grade 1, 2, or 3 ACL tears with less than 1 cm retraction were eligible for this study. Eligible patients were treated with an intraligamentous injection of autologous bone marrow concentrate, using fluoroscopic guidance. Pre- and postprocedural sagittal MRI images of the ACLs were analyzed using ImageJ software to objectively quantify changes between pre- and posttreatment scans. Five different types of measurement of ACL pixel intensity were examined as a proxy for ligament integrity. In addition pain visual analog scale (VAS) and Lower Extremity Functional Scale (LEFS) values were recorded at baseline and at 1 month, 3 months, 6 months, and annually postinjection. Objective outcomes measured were pre- to post-MRI measurement changes, as analyzed by the ImageJ software. Subjective outcomes measured were changes in the VAS and LEFS, and a self-rated percentage improvement. Results Seven of ten patients showed improvement in at least four of five objective measures of ACL integrity in their postprocedure MRIs. In the entire study group, the mean gray value, median, raw integrated density, and modal gray value all decreased toward low-signal ACLs (P=0.01, P=0.02, P=0.002, and P=0.08), indications of improved ligament integrity. Seven of ten patients responded to the self-rated metrics follow up. The mean VAS change was a decrease of 1.7 (P=0.25), the mean LEFS change was an increase of 23.3 (P=0.03), and mean reported improvement was 86.7%. Conclusion Based on this small case series, autologous bone marrow concentrate shows promise in the treatment of grade 1, 2, and possibly grade 3 ACL tears without retraction. Further investigation using a controlled study design is warranted.
Computer analysis of lighting style in fine art: steps towards inter-artist studies

Stylometry in visual art-the mathematical description of artists' styles - has been based on a number of properties of works, such as color, brush stroke shape, visual texture, and measures of contours' curvatures. We introduce the concept of quantitative measures of lighting, such as statistical descriptions of spatial coherence, diuseness, and so forth, as properties of artistic style. Some artists of the high Renaissance, such as Leonardo, worked from nature and strove to render illumination "faithfully" photorealists, such as Richard Estes, worked from photographs and duplicated the "physics based" lighting accurately. As such, each had dierent motivations, methodologies, stagings, and "accuracies" in rendering lighting clues. Perceptual studies show that observers are poor judges of properties of lighting in photographs such as consistency (and thus by extension in paintings as well); computer methods such as rigorous cast-shadow analysis, occluding-contour analysis and spherical harmonic based estimation of light fields can be quite accurate. For this reasons, computer lighting analysis can provide a new tools for art historical studies. We review lighting analysis in paintings such as Vermeer's Girl with a pearl earring, de la Tour's Christ in the carpenter's studio, Caravaggio's Magdalen with the smoking flame and Calling of St. Matthew) and extend our corpus to works where lighting coherence is of interest to art historians, such as Caravaggio's Adoration of the Shepherds or Nativity (1609) in the Capuchin church of Santa Maria degli Angeli. Our measure of lighting coherence may help reveal the working methods of some artists and in diachronic studies of individual artists. We speculate on artists and art historical questions that may ultimately profit from future renements to these new computational tools.
Design of a test chamber for investigation of moisture transport in air flows and porous materials

This paper describes the design of a test chamber for the investigation of the interaction of humid air and porous materials. Currently computational fluid dynamics (CFD) is gaining in importance as a tool to model the indoor climate in buildings. Meanwhile coupled CFD-material models are being developed which are capable of modelling moisture exchange between air and materials. The newly developed climate chamber can be used to validate these models.
Graphene Reinforced Carbon Nanotube Networks for Wearable Strain Sensors

Transparent, stretchable films of carbon nanotubes (CNTs) have attracted significant attention for applications in flexible electronics, while the lack of structural strength in CNT networks leads to deformation and failure under high mechanical load. In this work, enhancement of the strength and load transfer capabilities of CNT networks by chemical vapor deposition of graphene in the nanotube voids is proposed. The graphene hybridization significantly strengthens the CNT networks, especially at nanotube joints, and enhances their resistance to buckling and bundling under large cyclic strain up to 20%. The hybridized films show linear and reproducible responses to tensile strains, which have been applied in strain sensors to detect human motions with fast response, high sensitivity, and durability.
QoS-Aware Energy-Efficient Downlink Predictive Scheduler for OFDMA-Based Cellular Devices

We propose a predictive energy-efficient scheduling scheme that optimizes the user equipment (UE)'s bits/joule metric subject to quality-of-service (QoS) constraints in downlink orthogonal frequency-division multiple access (OFDMA) systems. This is achieved by minimizing the number of wake-up transmission time intervals (TTIs), where the UE receiver circuit is on, in a longer time horizon than studied before. The proposed predictive scheduler is supported by a ray-tracing (RT) engine that increases the scheduler's knowledge by long-term information about the users' propagation characteristics. A convex multiobjective binary-integer-programming formulation for the problem is presented to optimize both the UE's energy efficiency (EE) and QoS. The multiobjective formulation is then used for benchmarking of a low-complexity and computationally efficient heuristic scheduler. The results show that the proposed schedulers have significantly improved the UE's EE and the overall capacity of the system, compared with a recently published EE scheduling scheme while maintaining target QoS.
An Evaluation of Water Quality from Siahrod River, Haraz River and Babolrood River by NSFWQI index

In many countries such as Iran, social and industrial developments changed the qualitative characteristics of the river‘s water quality and leads to excessive pollution. The first step for river water quality management is obtaining information on changes of river water quality in dimensions of time and place and also, determination of major sources of pollutants. WQI is a mathematical and statistical tool for conversion of quantitative values of large quantity of water quality data into single number which presents a simple and understandable tool for qualitative assessment. In current study, samples were collected from stations at up, middle and downstream of three rivers in Mazandaran province (Siahrod River, Haraz River and Babolrod River) in a 2 years interval of 2012-2013 years. The values of NSFWQI (water quality index of America’s national health organization) were calculated for all stations and all of the stations were located on the level of unsuitable conditions. According to NSFWQI, the best condition was related to the upstream of Haraz River and the worst condition was related to the downstream of Siahrood River.
Degradation of polyethylene microplastics in seawater: Insights into the environmental degradation of polymers

ABSTRACT Microplastic contamination of aquatic environments has become an increasingly alarming problem. These, defined as particles <5 mm, are mostly formed due to the cracking and embrittlement of larger plastic particles. Recent reports show that the increasing presence of microplastics in the environment could have significant deleterious consequences over the health of marine organisms, but also across the food chain. Herein, we have studied the effects of artificial seawater on polyethylene (PE)-based beads by exposing them up to eight weeks to saltwater in stirred batch reactors in the dark and examined the structural and morphological changes these endured. Electron microscopy observations showed that artificial seawater induces severe microcracking of the pellets' surfaces. Additionally, Fourier transform infrared spectroscopy (FTIR) analyses evidenced the formation of oxidized groups whenever these particles were exposed to water and an increase in organic matter content of the waters in which the pellets were kept was evidenced by Raman spectroscopy. There were also noticeable consequences in the thermal stability of the polyethylene pellets, as determined by thermogravimetric studies (TGA). Furthermore, the parallel exposure of polyethylene pellets to UV radiation yielded less pronounced effects, thus underscoring its lower preponderance in the degradation of this material. These results highlight the importance of determining the mechanisms of degradation of microplastics in marine settings and what the implications may be for the environment. Overall, the herein presented results show that a relatively short period of time of accelerated exposure can yield quantifiable chemical and physical impacts on the structural and morphological characteristics of PE pellets.
Use of black soldier fly larvae (Hermetia illucens) to substitute soybean meal in ruminant diet: An in vitro rumen fermentation study

Aim: This experiment aimed to evaluate substitution of soybean meal (SBM) by black soldier fly (BSF) larvae meal in a napier grass diet as performed by an in vitro rumen fermentation system. Materials and Methods: Samples of napier grass, SBM, and BSF larvae age 1 week (BSF1) and 2 weeks (BSF2) were arranged according to the following dietary treatments (dry matter [DM] basis): T1, 100% napier grass; T2, 60% napier grass + 40% SBM; T3, 60% napier grass + 40% BSF1; T4, 60% napier grass + 40% BSF2; T5, 60% napier grass + 20% SBM + 20% BSF1; and T6, 60% napier grass + 20% SBM + 20% BSF2. The samples were determined for their chemical composition and were incubated in vitro using buffered rumen fluid for 48 h at 39°C. In vitro incubation was carried out in three runs and represented by two incubation bottles per run. Results: Supplementation of BSF, both BSF1 and BSF2, increased ether extract, neutral- and acid-detergent insoluble crude protein contents of T3-T6 diets. The T3 or T4 diet resulted in lower ruminal ammonia concentration, in vitro DM digestibility, and in vitro organic matter (OM) digestibility as compared to those in T2 (p<0.05). Diet supplemented with BSF produced lower methane emission in comparison to that of supplemented with SBM (p<0.05). Diet containing BSF2 produced lower methane and methane per digestible OM than that containing BSF1 (p<0.05). Conclusion: Substitution of SBM by BSF in ruminant diet results in a lower nutritional value in vitro but with an advantage of lowering ruminal methane emission.
Disparities in Non-Fatal Health Outcomes in Pediatric General Trauma Studies

When prevention efforts fail, injured children require high-quality health services to support their recovery. Disparities in non-fatal injury outcomes, an indicator of health-care quality, have received minimal attention. We evaluated the extent to which general trauma follow-up studies published in the peer-reviewed scientific literature provide evidence of socially patterned inequities in health, functional or disability outcomes ≥4 weeks after childhood injuries. Using a systematic search, we identified 27 eligible cohort studies from 13 high-income countries. We examined the extent to which the reported health outcomes varied across the PROGRESS criteria: place of residence, race/ethnicity, occupation, gender/sex, religion, socio-economic status, and social capital. The available evidence on differential outcomes is limited as many studies were compromised by selection or retention biases that reduced the participation of children from demographic groups at increased risk of adverse outcomes, or the analyses mainly focused on variations in outcomes by sex. Given the limited research evidence, we recommend greater attention to systematic collection and reporting of non-fatal injury outcomes disaggregated by socio-demographic indicators in order to identify disparities where these exist and inform equity-focused interventions promoting the recovery of injured children.
Arbitrary view transformation model for gait person authentication

Camera-based gait recognition is a useful method for authenticating a person from a distance, even if the resolution of the acquired images is not high. However, different views of the compared gallery and probe decrease the recognition accuracy. To solve this problem, we propose a gait based authentication method that uses an arbitrary view transformation scheme. The proposed method constructs a transformation matrix associated with the view of the set of gallery and probe using a 3D gait database composed of non-target multiple subjects' visual hulls. This matrix is used to transform the gallery gait features with varying views into features with the same view as the probe. Using this scheme, we can minimize the impact of the view difference. We evaluated the accuracy of the proposed method using a gait database composed of 52 subjects. The experimental results show that the proposed method is promising.
Epidermal surface lipids

A layer of lipids, which are of both sebaceous and keratinocyte origin, covers the surface of the skin. The apparent composition of surface lipids varies depending on the selected method of sampling. Lipids produced by the epidermal cells are an insignificant fraction of the total extractable surface lipid on areas rich in sebaceous glands. Due to the holocrine activity of the sebaceous gland, its product of secretion (sebum) is eventually released to the surface of the skin and coats the fur as well. Lipids of epidermal origin fill the spaces between the cells, like mortar or cement. The sebaceous lipids are primarily non polar lipids as triglycerides, wax esters and squalene, while epidermal lipids are a mixture of ceramides, free fatty acids and cholesterol. The composition of the sebaceous lipids is unique and intriguing and elevated sebum excretion is a major factor involved in the pathophysiology of acne. Recent studies have elucidated the roles that epidermal surface lipids have on normal skin functions and acne.
Fixed-Point Continuation for l1-Minimization: Methodology and Convergence

We present a framework for solving the large-scale $\ell_1$-regularized convex minimization problem:\[ \min\|x\|_1+\mu f(x). \] Our approach is based on two powerful algorithmic ideas: operator-splitting and continuation. Operator-splitting results in a fixed-point algorithm for any given scalar $\mu$; continuation refers to approximately following the path traced by the optimal value of $x$ as $\mu$ increases. In this paper, we study the structure of optimal solution sets, prove finite convergence for important quantities, and establish $q$-linear convergence rates for the fixed-point algorithm applied to problems with $f(x)$ convex, but not necessarily strictly convex. The continuation framework, motivated by our convergence results, is demonstrated to facilitate the construction of practical algorithms.
Presynaptic Control of Rapid Estrogen Fluctuations in the Songbird Auditory Forebrain

Within the CNS of vertebrates, estrogens can directly modulate neural circuits that govern a wide range of behaviors, including feeding, spatial navigation, reproduction, and auditory processing. The rapid actions of estrogens in brain (seconds to minutes) have become well established, but it is unclear how estrogens are synthesized and released within restricted temporal and spatial domains in neural circuits. Anatomical localization of the estrogen synthesis enzyme (aromatase) within presynaptic terminals suggests that neuroestrogens can be synthesized directly at the neuronal synapse. A consequent prediction follows that synaptic estrogen production is controlled via classical electrochemical events in neurons. Here, we present evidence that acute fluctuations in local neuroestrogen levels in the forebrain of the zebra finch depend on calcium influx within presynaptic terminals. In vivo experiments using microdialysis linked to a sensitive estrogen ELISA showed that local forebrain neuroestrogens were both suppressed by potassium-evoked excitation and upregulated during 30 min periods of extracellular calcium depletion in a region enriched with presynaptic aromatase. Furthermore, potassium-evoked changes in local neuroestrogens were blocked by targeted delivery of the voltage-gated calcium channel blocker ω-conotoxin GVIA. Together, these experiments indicate that neuroestrogens are controlled by specific, depolarization-sensitive, calcium-dependent events within forebrain presynaptic terminals.