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We explore the effects of voluntary environmental regulation (VER) and mandatory environmental regulation (MER) on green innovation (GI) and further assess the moderating effects of foreign direct investment (FDI). The results indicate that (1) Both VER and MER have positive local and spillover effects on GI. (2) VER can improve GI more effectively than MER. (3) FDI can enhance the effects of both VER and MER on GI. (4) In the long term, VER has positive local and spillover effects on GI, and FDI enhances these relationships. [ABSTRACT FROM AUTHOR]

Rubber–sand mixture (RSM), an environmentally friendly material, has been used in the pavement subgrade. Previous studies investigate the cyclic response of RSM with various rubber contents by triaxial devices under traffic loads without principal stress rotation (PSR). However, single-lane and multilane traffic moving loads generate unidirectional and multidirectional PSR, respectively, which may lead to more permanent deformation of the subgrade than the loads without PSR. To further understand the load–deformation relationship of RSM under the traffic loads, a series of cyclic drained tests involving the uni- and multidirectional PSR were performed on RSM and pure sand. The rubber contents determined by volume varied from 10% to 30%, and the specimens were consolidated under various stress levels to obtain different densities. The results indicate that multilane traffic loads generally produce more permanent vertical strain than single-lane traffic loads. The permanent vertical strain reduces with increasing rubber content, while a higher rubber content results in a larger plastic shear strain. In addition, an energy-based approach was employed to investigate the relationship between shakedown behavior and dissipated energy. The dissipated energy within one cycle tends to decline with loading cycles. The difference in dissipated energy between two different loading cycles is below a certain value when shakedown occurs. The findings provide an understanding of the stress–strain response of RSM under various traffic conditions and recommend a rubber content for RSM-subgrade design. [ABSTRACT FROM AUTHOR]

It is well recognized that the liquefaction resistance is closely related to the consolidation stress in soils. However, previous studies investigated the effects of unidirectional consolidation loads rather than multi-directional consolidation loads on liquefaction resistance. In this study, two types of granular materials, spherical glass beads and irregularly-shaped sands, are tested under undrained conditions with the uni- and bi-directional loads to investigate the liquefaction resistance. The effects of consolidation loads on liquefaction resistance can be explained in terms of material anisotropy. In simple shear tests, the stress- and strain-controlled loading paths are adopted for the consolidation and the undrained shear process, respectively. The results indicate that the liquefaction resistances of both materials consolidated under the multi-directional consolidation loads are higher than those consolidated under the linear loads. More consolidation loading cycles induce a better liquefaction resistance of the specimens at a given relative density. In addition, the influence of consolidation stress on liquefaction resistance is demonstrated by the anisotropy of specimens. Cyclic vertical stress, unidirectional shear stress, and bidirectional shear stress applied during consolidation produce greater isotropy and improve the liquefaction resistance of the specimen compared with the monotonic vertical stress, and their effects align with an increasing order. [ABSTRACT FROM AUTHOR]

Although the undrained shear strength has been widely studied for evaluating the factor of safety in slope, the effects of the initial shear stress induced by slope inclination are not fully understood. Some studies begin considering the conditions where the secondary shear direction along the direction of slope inclination, namely unidirectional shears. In the submarine environment, however, two directions are required to properly evaluate the true multidirectional shear strength because of the random direction of the wave and seismic load. This paper reports the bi-directional shear behavior of the Leighton Buzzard sand (Fraction B) from a specifically designed experimental program. The stress-strain relation, pore water pressure development, and flow liquefaction line are discussed. The test results show that the stress ratio at the peak of the stress-strain curve, called the gradient of flow liquefaction line, is unique for given vertical consolidation stress regardless of the direction and amount of initial shear stress. Though the sand behavior varies between different shear methods (bi-directional and unidirectional shear), the stress ratio at the initiation of instability is almost identical. Therefore, the total shear strength for submarine slopes under bi-directional shear conditions can be predicted through the constant gradient value of flow liquefaction line. [ABSTRACT FROM AUTHOR]

Traffic-load-induced principal stress rotation has been widely studied. Most of these tests were conducted using a hollow cylinder apparatus to simulate ground-level traffic conditions, and only one shear direction was considered. However, fewer studies focused on the stress conditions of subsoil below slopes or embankments, which involved bidirectional shear. In this study, a series of bidirectional cyclic simple shear tests were performed using the variable-direction dynamic cyclic simple shear apparatus to investigate the effects of multidirectional principal stress rotation on sand induced by traffic loads. The specimens were first Kα -consolidated with various static shear stresses and then subjected to traffic-induced cyclic shearing in different directions. The experimental results showed that both the magnitude and orientation of the initial static shear stress had significant effects on sand strain development and stress–strain behavior. A larger angle led to a higher axial strain, while larger initial shear stresses led to stiffer sand responses. [ABSTRACT FROM AUTHOR]

Asphalt binder is a complex mixture of dark brown polymers composed of hydrocarbons with generally poor fire resistance. To improve its flame retardancy when used in tunnel asphalt pavements, a new inorganic flame-retardant filler (FR) containing magnesium hydroxide, aluminum hydroxide, inorganic phosphate, and melamine salt was explored. Thereafter, limiting oxygen index (LOI) and smoke suppression tests for the flame-retarded asphalt binder (FRA) mastics mixed with FR and styrene-butadiene-styrene (SBS) copolymer asphalt binder were conducted. Thermogravimetric (TG) and differential scanning calorimetry (DSC) curves for the FRA were correspondingly generated. Based on the TG data, the reaction function g(α), apparent activation energy Ea, and pre-exponential factor A were quantitatively evaluated using kinetic analysis. In addition, a Fourier transform infrared spectrometry (FTIR) test was utilized to assess the effects of the presence of FR on the chemical composition of the asphalt binder. Dynamic shear rheometer (DSR) tests were also performed to evaluate the rheological behavior of FRA. Results show that the presence of the FR significantly reduced the LOI and improved the smoke suppression during combustion of the asphalt binder mastics. The presence of FR was found to increase the Ea and the complexity of the combustion reaction, thereby improving the flame retardancy of the asphalt binder. FTIR analysis indicated that the presence of FR did not induce any strong chemical reactions to significantly impact or alter the functional groups of the asphalt binder. Furthermore, it was also observed that the rutting parameter and critical failure temperature of FRA increased with the addition of FR due to the stiffening effect of the solid FR particles. [ABSTRACT FROM AUTHOR]

Featured Application: This paper presents the trends in the rheological, chemical, and morphological properties of SBS-modified asphalt-binders under multiple cycles of aging and rejuvenation. The results from this study may provide guidance for the future development of rejuvenators and application of repeated penetrating rejuvenation. To investigate the influence of multiple cycles of aging and rejuvenation on the rheological, chemical, and morphological properties of styrene–butadiene–styrene (SBS)-modified asphalt-binders, the asphalt-binders were aged using two laboratory simulation methods, namely a rolling thin film oven (RTFO) test for short-term aging and pressure aging vessel (PAV) for long-term aging. The asphalt-binders were then rejuvenated with three types of rejuvenators (Type I, II, and III) with different dosages (i.e., 6%, 10%, and 14% for the first, second, and third rejuvenation, respectively). A dynamic shear rheometer (DSR) was then used to analyze the effect of rejuvenators on the rheological properties of all the asphalt-binders. The changes in the functional groups and microscopic morphology in the process of multiple aging and rejuvenation cycles were studied using Fourier transform infrared (FTIR) and atomic force microscopy (AFM). The results indicated that the three rejuvenators could soften the stiffness and restore the microstructures of the aged asphalt-binders in the process of repeated aging and rejuvenation from DSR and AFM testing. Considering the rutting and fatigue properties, the Type I rejuvenator exhibited the potential to achieve the desired rejuvenation effects under multiple rejuvenation cycles. During the multiple aging and rejuvenation cycles, the aging resistance of SBSMA decreased gradually from the FTIR results. This inherently limited the number of repeated rejuvenation cycles. This research is conducive to promoting the application of repeated penetrating rejuvenation. [ABSTRACT FROM AUTHOR]

Geriatric hip fractures benefit from timely surgery. At the onset of the corona-virus disease 2019 (COVID-19) pandemic, shelter-in-place (SIP) orders were mandated in high-risk cities. The authors hypothesized that geriatric patients with hip fractures were more likely to present to the hospital greater than 24 hours after injury during SIP orders. They retrospectively reviewed patients 65 years or older who presented with hip fractures between March 20, 2020, and May 24, 2020 (SIP group), and between March 20, 2019, and May 24, 2019 (historical group). Primary outcomes were incidence of presentation greater than 24 hours after injury and mean number of days between injury and presentation. Secondary outcomes were incidence of preoperative deep venous thrombosis (DVT) and 30- and 90-day mortality rates. Thirty-three patients comprised the SIP group, and 50 patients comprised the historical group. There were no significant differences in their demographics or medical comorbidities. The SIP group was more likely to present greater than 24 hours after injury (P=.05) and presented a greater number of days after injury (P=.02). There was a significant difference in the incidence of preoperative DVT (P=.03). There were no significant differences in 30- and 90-day mortality rates. Geriatric patients who sustained hip fractures during SIP restrictions for COVID-19 were more likely to present greater than 24 hours after injury, have a greater number of days between injury and presentation, and be diagnosed with a preoperative DVT. [Orthopedics. 2021;44(4):223-228.]. [ABSTRACT FROM AUTHOR]

To evaluate the physical and rheological properties of rejuvenated styrene-butadiene-styrene-modified asphalt (SBSMA) binders designed for rapid in-place pavement recycling, an aged SBSMA binder was rejuvenated with three rejuvenators (i.e., Types I, II, and III) in different dosages. The physical properties of rejuvenated SBSMA were obtained to determine the optimal type and dosage of rejuvenators for the first and second rejuvenation. Performance grade (PG) tests, multiple stress creep recovery (MSCR) tests, and linear amplitude sweep (LAS) tests were conducted to measure the rheological properties using the dynamic shear rheometer (DSR) and bending beam rheometer (BBR). The results exhibited that the rejuvenators could soften the multiple aged binder and enhance its high- and low-temperature performance. The rejuvenation effect of rejuvenator Type I with the optimal dosage of 6∼8% was the most appropriate for the first rejuvenation. The optimal dosage of the second rejuvenation was 10∼12%. The addition of rejuvenators decreased the rutting factor G ∗ / sin δ , creep stiffness (S), delta Tc (ΔTc) parameter, recovery response (R), and yield stress of rejuvenated SBSMA. On the other hand, an increase in the rate of relaxation (m-value), nonrecoverable creep compliance (Jnr), and yield strain of rejuvenated SBSMA was recorded. Overall, the study findings indicated an improvement in the elastic properties of rejuvenated SBSMA, which contributes to improving the rutting, thermal, and fatigue cracking resistance of asphalt binder and ultimately the response of asphalt pavements. [ABSTRACT FROM AUTHOR]

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Aging has a detrimental impact on the interfacial interaction and bonding between asphalt-binder and aggregates, which influence ultimately on the performance of asphalt mixtures and pavements. Evaluation of the mechanical properties of the interface between the asphalt-binder and aggregates has thus become a hot research topic, particularly as a function of aging. In this study, the interfacial tensile strength, compressive strength, elastic modulus, and interfacial recovery energy were measured and quantified using molecular dynamic simulation. Whilst the free volume of the asphalt mixtures exhibited sensitivity to aging, the interfacial tensile strength decreased with an increase in the degree of aging. In general, the mechanical properties of the asphalt-binder-aggregate interface were found to be significantly dependent on the aggregate type. Furthermore, the study results indicated that interfacial recovery energy is a key characteristic property for characterizing the interfacial adhesive force within asphalt mixtures. Overall, the study of mechanical properties of the asphalt-binder and aggregate interface, as presented in this paper, contributes to quantifying the adhesive properties and improving the performance of asphalt mixtures. [ABSTRACT FROM AUTHOR]

Objectives: Geriatric patients who sustain hip fractures and are taking factor Xa inhibitors (Xa-I) experience surgical delay. Our institution developed a pharmacokinetic protocol to formally guide and expedite surgical timing for these patients. The protocol is based on the patient's renal function and timing of last Xa-I dose. For patients with impaired renal function, longer wait times are recommended. The purpose of this study was to determine the effects of this protocol for patients with geriatric hip fracture taking Xa-I., Design: Retrospective cohort study., Setting: Level 1 trauma center., Patients/participants: A total of 164 patients aged 65 and older who were taking Xa-I before admission and underwent hip fracture surgery; 68 patients in the Standard group (2014-2018) and 96 patients in the Expedited group (2020-2022, after protocol implementation)., Intervention: Hip fracture surgery., Main Outcome Measurements: Time to surgery (TTS), transfusion rate, blood loss, 90-day complication rates., Results: The median TTS was significantly shorter in the Expedited group (28.6 hours, interquartile range 21.3 hours) than in the Standard group (44.8 hours, interquartile range 21.1 hours) ( P < .001). There were no differences in overall transfusion rates. Multivariable regression analysis demonstrated that time to surgery was not predictive of transfusion rate in all patients (OR 1.00, 95% CI 0.99-1.02, P = .652). There were no differences in blood loss or rates of 90-day complications., Conclusion: Geriatric patients with hip fractures and taking factor Xa inhibitors may warrant earlier surgery without an increased risk of transfusion or bleeding., Level of Evidence: Therapeutic Level III., Competing Interests: All authors have read and complied with the ethical approval/informed consent requirements. All ethics statements have been added to the Materials and Methods section in the manuscript. The authors report no conflict of interest related to the research or manuscript. No funding was received for this study., (Copyright © 2023 The Authors. Published by Wolters Kluwer Health, Inc. on behalf of the Orthopaedic Trauma Association.)

Background: Proximal interphalangeal (PIP) fracture dislocations remain a complex injury pattern to treat. There are several treatment methods available aimed to restore stability, preserve range of motion, and reconstitute the articular surface. This study looked at the mid-term clinical and radiographic results of open reduction internal fixation through a shotgun approach of comminuted PIP fracture dislocations., Methods: A retrospective review was conducted of all PIP fracture dislocations treated through a volar, shotgun approach at a single institution over a 15-year period. Patients identified were contacted and asked to return to the office for clinical and radiographic evaluation. Patient reported outcomes were assessed with the Michigan hand questionnaire (MHQ) and visual analog scale (VAS) for pain., Results: 5 patients returned to the office for further evaluation with average follow-up of 69 months (range, 33-133 months). 3 patients were found to have post traumatic arthritis on radiographs. 1 case had recurrent instability and one case had a deep infection, both necessitating further surgical intervention. Average PIP arc of motion was found to be 79°. Average VAS score of 0 and MHQ result of 95 (out of a possible score of 100) indicating no residual pain and excellent functionality of the affected hand., Conclusion: Open reduction internal fixation of comminuted PIP fracture dislocations utilizing the volar, shotgun approach provides excellent mid-term functional results despite the high incidence of post traumatic arthritis.

Objective: Laparoscopy-assisted gastrectomy for advanced gastric cancer still remains controversial. The aim of this study is to compare oncologic feasibility and technical safety of laparoscopic versus open gastrectomy for advanced gastric cancer with D2 lymphadenectomy by comparing patients' short-term postoperative outcomes., Methods: One hundred and one patients with laparoscopy-assisted gastrectomy and 101 patients with open gastrectomy were one-to-one matched and then compared in terms of operative outcomes and hospital courses., Results: The laparoscopic group showed significantly longer operating time (297.4 vs. 198.1 min, P < 0.001), earlier first flatus time (2.8 vs. 3.6 days, P < 0.001), earlier diet start time (3.8 vs. 4.6 days, P < 0.001), shorter hospital stay (10.5 vs. 11.9 days, P < 0.001) and less morbidity (21.8 vs. 37.6%, P = 0.019). However, retrieval lymph nodes, intraoperative blood loss, transfused patients, postoperative fever and mortality were similar in the two groups. As for complications, incision infection (1.0 vs. 8.9%, P = 0.021) was significantly more common in the open group than in the laparoscopic group. In the subgroup comparisons of outcomes of laparoscopy-assisted gastrectomy, the tumor, node, metastasis III group showed significantly increased retrieval lymph nodes (37.2 vs. 31.0, P < 0.001), increased intraoperative blood loss (147.2 vs. 120.5 ml, P = 0.010), increased length of hospital stay (11.1 vs. 9.9 days, P < 0.001) and increased morbidity (32.6 vs. 13.8%, P = 0.024) when compared with the tumor, node, metastasis II group., Conclusions: Laparoscopy-assisted gastrectomy is feasible and safe for the treatment of advanced gastric cancer with D2 lymphadenectomy compared with open gastrectomy. Higher-level tumor stage (tumor, node, metastasis III) may increase the operative risk and should be performed with caution by surgeons with considerable experience of laparoscopic gastrectomy., (© The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)