S1 Dataset -

PurposeAfter spinal surgery, negative pressure wound treatment (NPWT) improves deep surgical site infection (DSSI) wound healing. This research compared the healing benefits of two sponge implantation strategies in NPWT for DSSI.Methods21 patients with DSSI utilized NPWT to improve wound healing following spine surgery were followed from January 1, 2012 to December 31, 2021. After antibiotic treatment failure, all these patients with DSSI received extensive debridement and NPWT. They are grouped by sponge placement method: centripetal reduction and segment reduction. The two groups’ hospital stays, NPWT replacement frequency, wound healing time, healing speed, and quality of wound healing (POSAS score) were compared.ResultsAll patients had been cured by the end of December 2022, and the mean follow-up time was 57.48 ± 29.6 months. Surgical incision length did not vary across groups (15.75±7.61 vs. 15.46±7.38 cm, P = 0.747). The segmental reduction approach had shorter hospital stay and NPWT treatment times than the centripetal reduction method (39.25±16.04 vs. 77.38±37.24 days, P = 0.027). Although there is no statistically significant difference, the mean wound healing duration of segmental reduction group is faster than that of centripetal reduction group (0.82±0.39 vs 0.45±0.28 cm/d, P = 0.238), wound healing quality (POSAS) (33.54±8.63 vs 48.13±12.17, P = 0.408) is better in segmental reduction group, and NPWT replacement frequency (2.62 ± 1.04 vs 3.88 ± 1.25, P ConclusionsNPWT heals wounds and controls infection. Segmental reduction method accelerates wound healing, reduces hospital stay, and improves wound quality compared to central reduction method.</div

Typical case of segment reduction method.

A 43-year-old man underwent lumbar spondylolisthesis reduction and internal fixation for lumbar spondylolisthesis. Six months after the operation, he developed an incision sinus with pus and was referred to our hospital. (A) The incision was thoroughly debridement, and the deep wound was covered with sponge. (B, C) The sponge was trimmed into several pieces, each with a width of 1 cm and a thickness of 1 cm, and placed at intervals to the incision. Sutures were made at 2 cm intervals, and the separate sponges were attached to the main sponge. (D) Connect the negative pressure drainage device for continuous negative pressure drainage. (E) At intervals of 5–7 days, the sponge is replaced. When the deep tissue is well covered, the incision is sutured as appropriate. (F) The wound scar healed well.</p

STROBE statement—checklist of items that should be included in reports of observational studies.

STROBE statement—checklist of items that should be included in reports of observational studies.</p

Clinical results between two groups.

PurposeAfter spinal surgery, negative pressure wound treatment (NPWT) improves deep surgical site infection (DSSI) wound healing. This research compared the healing benefits of two sponge implantation strategies in NPWT for DSSI.Methods21 patients with DSSI utilized NPWT to improve wound healing following spine surgery were followed from January 1, 2012 to December 31, 2021. After antibiotic treatment failure, all these patients with DSSI received extensive debridement and NPWT. They are grouped by sponge placement method: centripetal reduction and segment reduction. The two groups’ hospital stays, NPWT replacement frequency, wound healing time, healing speed, and quality of wound healing (POSAS score) were compared.ResultsAll patients had been cured by the end of December 2022, and the mean follow-up time was 57.48 ± 29.6 months. Surgical incision length did not vary across groups (15.75±7.61 vs. 15.46±7.38 cm, P = 0.747). The segmental reduction approach had shorter hospital stay and NPWT treatment times than the centripetal reduction method (39.25±16.04 vs. 77.38±37.24 days, P = 0.027). Although there is no statistically significant difference, the mean wound healing duration of segmental reduction group is faster than that of centripetal reduction group (0.82±0.39 vs 0.45±0.28 cm/d, P = 0.238), wound healing quality (POSAS) (33.54±8.63 vs 48.13±12.17, P = 0.408) is better in segmental reduction group, and NPWT replacement frequency (2.62 ± 1.04 vs 3.88 ± 1.25, P ConclusionsNPWT heals wounds and controls infection. Segmental reduction method accelerates wound healing, reduces hospital stay, and improves wound quality compared to central reduction method.</div

A typical case of the centripetal reduction method.

The patient was a 59-year-old male who underwent L5-S1 spinal decompression and internal fixation in another hospital. One month after the operation, pus from the incision was seen in our hospital. The bacterial culture was Pseudomonas aeruginosa. (A-C) Thorough debridement of the incision and placement of a sponge to cover the wound. (D) Connect the negative pressure drainage device for continuous negative pressure drainage. (E) At intervals of 5–7 days, the sponge was replaced, and the size of the sponge was gradually reduced according to the wound healing. (F) Wound after healing.</p

Schematic diagram of two NPWT sponge placement methods.

(A-C) Centripetal reduction method. Take the whole sponge and place it at the incision. After the wound surface is gradually reduced, replace it with a smaller sponge. (D) Subsection reduction method. Trim the sponge into several pieces, each with a width of 1cm and a thickness of 1cm. They were placed at intervals to the incisions, sutured at 2 cm intervals, and the separated sponges were connected to the main sponge.</p

Baseline characteristics of participants.

PurposeAfter spinal surgery, negative pressure wound treatment (NPWT) improves deep surgical site infection (DSSI) wound healing. This research compared the healing benefits of two sponge implantation strategies in NPWT for DSSI.Methods21 patients with DSSI utilized NPWT to improve wound healing following spine surgery were followed from January 1, 2012 to December 31, 2021. After antibiotic treatment failure, all these patients with DSSI received extensive debridement and NPWT. They are grouped by sponge placement method: centripetal reduction and segment reduction. The two groups’ hospital stays, NPWT replacement frequency, wound healing time, healing speed, and quality of wound healing (POSAS score) were compared.ResultsAll patients had been cured by the end of December 2022, and the mean follow-up time was 57.48 ± 29.6 months. Surgical incision length did not vary across groups (15.75±7.61 vs. 15.46±7.38 cm, P = 0.747). The segmental reduction approach had shorter hospital stay and NPWT treatment times than the centripetal reduction method (39.25±16.04 vs. 77.38±37.24 days, P = 0.027). Although there is no statistically significant difference, the mean wound healing duration of segmental reduction group is faster than that of centripetal reduction group (0.82±0.39 vs 0.45±0.28 cm/d, P = 0.238), wound healing quality (POSAS) (33.54±8.63 vs 48.13±12.17, P = 0.408) is better in segmental reduction group, and NPWT replacement frequency (2.62 ± 1.04 vs 3.88 ± 1.25, P ConclusionsNPWT heals wounds and controls infection. Segmental reduction method accelerates wound healing, reduces hospital stay, and improves wound quality compared to central reduction method.</div

Superhydrophobic Cones for Continuous Collection and Directional Transportation of CO₂ Microbubbles in CO₂ Supersaturated Solutions

Microbubbles are tiny bubbles with diameters below 50 μm. Because of their minute buoyant force, the microbubbles stagnate in aqueous media for a long time, and they sometimes cause serious damage. Most traditional methods chosen for elimination of gas bubbles utilize buoyancy forces including chemical methods and physical methods, and they only have a minor effect on microbubbles. Several approaches have been developed to collect and transport microbubbles in aqueous media. However, the realization of innovative strategies to directly collect and transport microbubbles in aqueous media remains a big challenge. In nature, both spider silk and cactus spines take advantage of their conical-shaped surface to yield the gradient of Laplace pressure and surface free energy for collecting fog droplets from the environment. Inspired by this, we introduce here the gradient of Laplace pressure and surface free energy to the interface of superhydrophobic copper cones (SCCs), which can continuously collect and directionally transport CO₂ microbubbles (from tip side to base side) in CO₂-supersaturated solution. A gas layer was formed when the microbubbles encounter the SCCs. This offers a channel for microbubble directional transportation. The efficiency of microbubble transport is significantly affected by the apex angle of SCCs and the carbon dioxide concentration. The former provides different gradients of Laplace pressure as the driving force. The latter represents the capacity, which offers the quantity of CO₂ microbubbles for collection and transportation. We believe that this approach provides a simple and valid way to remove microbubbles

In Situ Wetting State Transition on Micro- and Nanostructured Surfaces at High Temperature

We studied the in situ transition of the droplets’ wetting state on the heated solid surfaces. The wetting behaviors of four micro- and nanostructured surfaces with different chemical components were studied. These parameters included the maximum contact areas (MCA), the maximum evaporation areas (MEA) and the wetting transition temperature (<i>T</i>_trans). The reduction in MEAs has a specific transition process from wetting (Wenzel state) or partial wetting (Wenzel-Cassie intermediate state) to nonwetting (Cassie State) as the surface temperature rises. When the MEAs drop to zero at a critical temperature (<i>T</i>_trans), the droplets rebound from the heated surfaces to complete the wetting transition process. The chemical compounds and the surfaces’ rough structure play an important role in the droplets’ wetting transition behavior. Before FAS-modification, microstructures can increase the MCAs, MEAs, and <i>T</i>_trans. However, the microstructures are less effective at increasing the MEAs and <i>T</i>_trans than changes to nanostructures. After FAS-modification, both the nano- and microstructures reduce the <i>T</i>_trans. On the FAS-MNSi surfaces, the MEAs are always zerothe droplets rebounded at room temperature, and the wetting transition did occur. We propose two high-temperature mechanisms to explain these transition phenomena

Reliable Manipulation of Gas Bubble Size on Superaerophilic Cones in Aqueous Media

Gas bubbles in aqueous media are ubiquitous in a broad range of applications. In most cases, the size of the bubbles must be manipulated precisely. However, it is very difficult to control the size of gas bubbles. The size of gas bubbles is affected by many factors both during and after the generation process. Thus, precise manipulation of gas bubble size still remains a great challenge. The ratchet and conical hairs of the Chinese brush enable it to realize a significant capacity for holding ink and transferring them onto paper continuously and controllably. Inspired by this, a superhydrophobic/superaerophilic cone interface is developed to manipulate gas bubble size in aqueous media. When the resultant force between the Laplace force and the axial component of the buoyancy force approaches zero, the gas bubble is held steadily by the superhydrophobic/superaerophilic copper cones in a unique position (balance position). A new kind of pressure sensor is also designed based on this principle