Deep learning with mixup augmentation for improved pore detection during additive manufacturing.

In additive manufacturing (AM), process defects such as keyhole pores are difficult to anticipate, affecting the quality and integrity of the AM-produced materials. Hence, considerable efforts have aimed to predict these process defects by training machine learning (ML) models using passive measurements such as acoustic emissions. This work considered a dataset in which keyhole pores of a laser powder bed fusion (LPBF) experiment were identified using X-ray radiography and then registered both in space and time to acoustic measurements recorded during the LPBF experiment. Due to AM's intrinsic process controls, where a pore-forming event is relatively rare, the acoustic datasets collected during monitoring include more non-pores than pores. In other words, the dataset for ML model development is imbalanced. Moreover, this imbalanced and sparse data phenomenon remains ubiquitous across many AM monitoring schemes since training data is nontrivial to collect. Hence, we propose a machine learning approach to improve this dataset imbalance and enhance the prediction accuracy of pore-labeled data. Specifically, we investigate how data augmentation helps predict pores and non-pores better. This imbalance is improved using recent advances in data augmentation called Mixup, a weak-supervised learning method. Convolutional neural networks (CNNs) are trained on original and augmented datasets, and an appreciable increase in performance is reported when testing on five different experimental trials. When ML models are trained on original and augmented datasets, they achieve an accuracy of 95% and 99% on test datasets, respectively. We also provide information on how dataset size affects model performance. Lastly, we investigate the optimal Mixup parameters for augmentation in the context of CNN performance.

Part 1: Evaluating Neck-Strengthening Protocols to Reduce the Incidence of Traumatic Brain Injury: Traditional vs. Nontraditional Neck-Strengthening Techniques.

ABSTRACT: Schroeder, LH, McDaniel, AT, Wang, Y, Dickens, GM, Pantani, V, and Kubinak, H. Part 1: evaluating neck-strengthening protocols to reduce the incidence of traumatic brain injury: traditional vs. nontraditional neck-strengthening techniques. J Strength Cond Res 38(1): 21-29, 2024-A common cause of traumatic brain injuries (TBIs) is the head's kinematic response to rapid movement, which can be reduced with dynamic neck strengthening. This study aimed to determine the most effective neck-strengthening program by comparing a traditional and nontraditional program. Isometric neck strength was assessed in 32 subjects randomly assigned to one of the traditional and nontraditional neck-strengthening programs. The nontraditional program used a novel neck-strengthening device. After weeks 6 and 10 of training, isometric neck strength was reassessed. With the collected data, linear mixed models were established to compare the changes in neck strength between the 2 groups during the 10-week training period. Statistical analysis results suggest that, for both cervical extension (CE) and cervical flexion (CF), subjects in the novel neck-strengthening device group had a significantly higher gain of strength during the 10 weeks than the traditional group. With test statistics of -2.691 and -3.203 and corresponding 2-sided p-value of 0.01289 and 0.003889, respectively, we conclude that there is a statistically significant difference in the linear slopes of increase for both CE and CF between the 2 groups. As to left cervical lateral flexion and right cervical lateral flexion, the novel neck strength group had increased strength gains compared with the traditional group. However, the increase was not enough to demonstrate significant findings. Results were considered significant at p < 0.05. The results of this study show that the novel neck-strengthening device may be an effective mechanism for preventing mild TBIs.

Capturing the conversion of the pathogenic alpha-1-antitrypsin fold by ATF6 enhanced proteostasis.

Genetic variation in alpha-1 antitrypsin (AAT) causes AAT deficiency (AATD) through liver aggregation-associated gain-of-toxic pathology and/or insufficient AAT activity in the lung manifesting as chronic obstructive pulmonary disease (COPD). Here, we utilize 71 AATD-associated variants as input through Gaussian process (GP)-based machine learning to study the correction of AAT folding and function at a residue-by-residue level by pharmacological activation of the ATF6 arm of the unfolded protein response (UPR). We show that ATF6 activators increase AAT neutrophil elastase (NE) inhibitory activity, while reducing polymer accumulation for the majority of AATD variants, including the prominent Z variant. GP-based profiling of the residue-by-residue response to ATF6 activators captures an unexpected role of the "gate" area in managing AAT-specific activity. Our work establishes a new spatial covariant (SCV) understanding of the convertible state of the protein fold in response to genetic perturbation and active environmental management by proteostasis enhancement for precision medicine.

Dynamics of pore formation during laser powder bed fusion additive manufacturing.

Laser powder bed fusion additive manufacturing is an emerging 3D printing technique for the fabrication of advanced metal components. Widespread adoption of it and similar additive technologies is hampered by poor understanding of laser-metal interactions under such extreme thermal regimes. Here, we elucidate the mechanism of pore formation and liquid-solid interface dynamics during typical laser powder bed fusion conditions using in situ X-ray imaging and multi-physics simulations. Pores are revealed to form during changes in laser scan velocity due to the rapid formation then collapse of deep keyhole depressions in the surface which traps inert shielding gas in the solidifying metal. We develop a universal mitigation strategy which eliminates this pore formation process and improves the geometric quality of melt tracks. Our results provide insight into the physics of laser-metal interaction and demonstrate the potential for science-based approaches to improve confidence in components produced by laser powder bed fusion.

GIP(3-30)NH2 is a potent competitive antagonist of the GIP receptor and effectively inhibits GIP-mediated insulin, glucagon, and somatostatin release.

Alternative processing of the precursor protein pro-GIP results in endogenously produced GIP(1-30)NH2, that by DPP-4 cleavage in vivo results in the metabolite GIP(3-30)NH2. We showed previously that GIP(3-30)NH2 is a high affinity antagonist of the human GIPR in vitro. Here we determine whether it is suitable for studies of GIP physiology in rats since effects of GIP agonists and antagonists are strictly species-dependent. Transiently transfected COS-7 cells were assessed for cAMP accumulation upon ligand stimulation or assayed in competition binding using human 125I-GIP(1-42) as radioligand. In isolated perfused rat pancreata, insulin, glucagon, and somatostatin-releasing properties were evaluated. Competition binding demonstrated that on the rat GIP receptor (GIPR), rat GIP(3-30)NH2 bound with high affinity (Ki of 17nM), in contrast to human GIP(3-30)NH2 (Ki of 250nM). In cAMP studies, rat GIP(3-30)NH2 inhibited GIP(1-42)-induced rat GIPR activation and schild-plot analysis showed competitive antagonism with a pA2 of 13nM and a slope of 0.9±0.09. Alone, rat GIP(3-30)NH2 displayed weak, low-potent partial agonistic properties (EC50>1µM) with an efficacy of 9.4% at 0.32µM compared to GIP(1-42). In perfused rat pancreata, rat GIP(3-30)NH2 efficiently antagonized rat GIP(1-42)-induced insulin, somatostatin, and glucagon secretion. In summary, rat GIP(3-30)NH2 is a high affinity competitive GIPR antagonist and effectively antagonizes GIP-mediated G protein-signaling as well as pancreatic hormone release, while human GIP(3-30)NH2, despite a difference of only one amino acid between the two (arginine in position 18 in rat GIP(3-30)NH2; histidine in human), is unsuitable in the rat system. This underlines the importance of species differences in the GIP system, and the limitations of testing human peptides in rodent systems.

A New Class of Tungsten-Containing Oxidoreductase in Caldicellulosiruptor, a Genus of Plant Biomass-Degrading Thermophilic Bacteria.

Caldicellulosiruptor bescii grows optimally at 78°C and is able to decompose high concentrations of lignocellulosic plant biomass without the need for thermochemical pretreatment. C. bescii ferments both C5 and C6 sugars primarily to hydrogen gas, lactate, acetate, and CO2 and is of particular interest for metabolic engineering applications given the recent availability of a genetic system. Developing optimal strains for technological use requires a detailed understanding of primary metabolism, particularly when the goal is to divert all available reductant (electrons) toward highly reduced products such as biofuels. During an analysis of the C. bescii genome sequence for oxidoreductase-type enzymes, evidence was uncovered to suggest that the primary redox metabolism of C. bescii has a completely uncharacterized aspect involving tungsten, a rarely used element in biology. An active tungsten utilization pathway in C. bescii was demonstrated by the heterologous production of a tungsten-requiring, aldehyde-oxidizing enzyme (AOR) from the hyperthermophilic archaeon Pyrococcus furiosus. Furthermore, C. bescii also contains a tungsten-based AOR-type enzyme, here termed XOR, which is phylogenetically unique, representing a completely new member of the AOR tungstoenzyme family. Moreover, in C. bescii, XOR represents ca. 2% of the cytoplasmic protein. XOR is proposed to play a key, but as yet undetermined, role in the primary redox metabolism of this cellulolytic microorganism.

In situ monitoring of surface postprocessing in large-aperture fused silica optics with optical coherence tomography.

Optical coherence tomography (OCT) is explored as a method to image laser-damage sites located on the surface of large aperture fused silica optics during postprocessing via CO2 laser ablation. The signal analysis for image acquisition was adapted to meet the sensitivity requirements for this application. A long-working-distance geometry was employed to allow imaging through the opposite surface of the 5 cm thick optic. The experimental results demonstrate the potential of OCT for remote monitoring of transparent material processing applications.

Ring avulsion: injury pattern, treatment, and outcome.

Ring avulsion injury is classically believed to be one of the most challenging for the reconstructive surgeon. Injury patterns include a spectrum from laceration to complete amputation, with differential magnitude of injury to soft tissue, tendon, joint complex, and bone. Although ring avulsion injury can result in devastating functional and aesthetic loss to the hand, fear of even greater functional loss has made replantation a relative contraindication for this complex injury. This article hopes to clarify the pathomechanics and anatomy of ring avulsion, such that the elements of injury, which lead to poor survival and poor function, can be adequately addressed in the surgical plan.

Infralimbic cortex projects to all parts of the pontine and medullary lateral tegmental field in cat.

The infralimbic cortex (ILc) in cat is the ventralmost part of the anterior cingulate gyrus. The ILc, together with the amygdala, bed nucleus of the stria terminalis and lateral hypothalamus, is involved in the regulation of fear behavior. The latter three structures are thought to take part in triggering the fear response by means of their projections to the pontine and medullary lateral tegmental field (LTF). The LTF is a large region extending from the parabrachial nuclei rostrally to the spinal cord caudally. It contains almost all the premotor interneurons for the brainstem and for some upper spinal cord motoneurons innervating the muscles of face, head and throat. The question is whether ILc also projects to the LTF. Such a pathway would allow the ILc to influence the fear response by acting directly on these premotor interneurons. Anterograde tracer injections were made in the medial surface of the cortex in four cats. Only when the injection sites involved ILc were anterogradely labeled fibers observed throughout the rostrocaudal extent of the LTF. To verify whether these projections indeed originated from ILc, in two other cases retrograde tracer injections were made in the pontomedullary LTF. The results showed many retrogradely labeled neurons in ILc, but none in adjacent cortical regions. These results show that the ILc projects to the LTF in cat and can possibly modulate the fear response not only via indirect but also via direct routes to the premotor interneurons in the brainstem.

Improving home care. A survey on physician and nurse communication.

Home health care is growing, and phone calls between physicians and home care nurses are essential to successful home care patient management. This preliminary study analyzed several aspects of the physician and home health nurse telephone communication, including effectiveness, time expenditure, percentage of calls resolved by physicians, and documentation of phone contacts between 90 medical/surgical physicians and six home health nurses in Cleveland, Ohio. The phone conversations involved 154 patient contacts during a 3-month period. Overall, we found 75% of the home calls were effective. Eighty-five percent of calls required 15 minutes or less for completion, 47% of nurse-generated calls were resolved by physicians, and 26% of calls were documented in the patient's medical record. Our results illuminated several aspects of home care communication amenable to improvement.

Nursing student practicums in home care.

In the next decades home care will become the setting of choice for health care delivery. Because of this trend, nursing education must begin offering a home care component to nursing degree candidates. One such program strives to better prepare students for the unique care delivery that in-home care demands.

Reaching for the ideal in home care.

Home care as delivered by agencies with Medicare as the primary source of reimbursement and by the Hospital Base Home Care programs in the Veteran's Administration system are described and compared. Physician-home care relationships are explored and team function is examined. Recommendations for the improvement in home care are made.