Deep Incision Research Articles

Sphenoderesjaponicus sp. nov. – The first deep water representative of the family Semnoderidae (Kinorhyncha, Cyclorhagida) in the sea of Japan

A new species of semnoderid kinorhynchs, Sphenoderes japonicus sp. nov. collected from oxidized brown silt on the steep slope of the deepest depression in the Sea of Japan, Northwestern Pacific, is described using light and scanning electron microscopy. This new representative of the family Semnoderidae is characterized by the structure of the first trunk segment consisting of externally closed cuticular ring with indistinct intracuticular tergosternal junctions. Cuticular ring of the first trunk segment is with deep and narrow middorsal incision and much broader midventral incision filled by large midventral placid. Acicular lateroventral spines on trunk segments 3–9. Lateroventral accessory spines are minute, only on trunk segment 5. Trunk segment 10 with acicular spines in laterodorsal position in female and in midlateral position in male. S. japonicus sp. nov. constitutes the first bathial species of this family and the first species of Semnoderidae in the Sea of Japan.

A Prospective Randomized Controlled Study of Stratafix versus Standard-of-Care for Deep Tissue Closure in Orthopedic Surgery.

Orthopedic deep surgical incisions require the approximation of 1 or multiple tissue layers. This prospective randomized controlled study aimed to assess the usefulness and effectiveness of a barbed suture technique (Stratafix symmetric PDS plus) versus the conventional interrupted knotted suture technique for deep tissue closure in orthopedic surgery by comparing deep fascia suture time, relative cost, and wound-related complications. A total of 254 patients with deep surgical incisions who underwent orthopedic surgery between October 1, 2020, and June 30, 2021, were recruited. Their general characteristics (age, sex, weight, height, body mass index, American Society of Anesthesiologists physical status score, total operation time, and length of deep incision) and factors related to deep incision wounds (suture type and number, wound closure time, and operation site outcomes) were collected. The general characteristics did not differ between the Stratafix and conventional groups. There were no between-group differences observed in total operation time or total anesthesia time. The wound suture times differed significantly. In the conventional group, the suture time per unit length was lower in the group with the length of deep incision under 20 cm but did not differ significantly for each wound size. In the Stratafix group, the suture time per unit length was lower in the group under 15 cm, with the shortest time observed for 10-14.9 cm, followed by 5.0-9.9 cm and the group under 5 cm. The conventional group developed 4 cases of superficial wound infection or surgical wound necrosis. One case of protruded suture tap occurred in the Stratafix group. The average suture time per unit length increased for lengths under 5 cm as barbed sutures required more time from the start of the first suture to finish of the last suture. There was no significant benefit for very short suture length. One barbed suture material allows a suture of approximately 10-12 cm; sutures beyond that require more time because the surgeon has to start again. The Stratafix group used less suture material than the conventional group.

A clinical application for arterial coupling and histomorphometric comparison of internal mammary and thoracodorsal arteries for safe use.

In breast reconstruction, arterial coupling has been reported to be more favorable in the thoracodorsal artery (TDA) than the internal mammary artery (IMA). This technique may help overcome anastomosis in a small, deep space. Understanding the arteries' mechanical properties is crucial for breast reconstruction's safety and success. Abdominal-based free flap breast reconstructions performed by a single surgeon between 2020 and 2022 were retrospectively analyzed. The patients were classified by microanastomosis technique (handsewn and coupler device) to compare the rate of vascular revision. Histomorphometric analysis of arterial coupling in TDA and IMA was performed in 10 fresh cadavers for comparing wall thickness and composition, including densities of elastic fiber, smooth muscle, and collagen. A total of 309 patients (339 reconstructed breasts) were included. There were 29 patients in the TDA handsewn group (A), 38 patients in the TDA coupler group (B), and 242 patients in the IMA handsewn group (C). The rates of arterial revision in groups A, B, and C were 0.00% (95%CI: 0.00%-11.03%), 2.5% (95%CI: 0.44%-12.88%), and 1.49% (95%CI: 0.58%-3.77%), respectively, with no statistically significant differences (p-value = .694). Histologically, the thickness of the tunica media and adventitia between IMA and TDA showed no significant difference. The density of elastic fiber was significantly higher in IMA (16.70%) than in TDA (0.79%) (p-value <.001). The histologic characteristics of TDA are more favorable for arterial coupling than those of IMA. Arterial coupling is a safe option in situations where TDA anastomosis must be performed through a narrow and deep incision.

Comparison of holmium:yttrium-aluminium-garnet (YAG), thulium fiber laser, and pulsed thulium:YAG lasers on soft tissue: an ex vivo study.

To assess laser-tissue interactions through ablation, coagulation, and carbonisation characteristics in a non-perfused porcine kidney model between three pulsed lasers: holmium (Ho): yttrium-aluminium-garnet (YAG), thulium fiber laser (TFL), and pulsed thulium (p-Tm):YAG. A 150-W Ho:YAG, a 60-W TFL, and a 100-W p-Tm:YAG lasers were compared. The laser settings that can be set identically between the three lasers and be clinically relevant for prostate laser enucleation were identified and used on fresh, unfrozen porcine kidneys. Laser incisions were performed using stripped laser fibers of 365 and 550 μm, set at distances of 0 and 1 mm from the tissue surface at a constant speed of 2 mm/s. Histological analysis evaluated shape, depth, width of the incision, axial coagulation depth, and presence of carbonisation. Incision depths, widths, and coagulation zones were greater with Ho:YAG and p-Tm:YAG lasers than TFL. Although no carbonisation was found with the Ho:YAG and p-Tm:YAG lasers, it was common with TFL, especially at high frequencies. The shapes of the incisions and coagulation zones were more regular and homogeneous with the p-Tm:YAG laser and TFL than with Ho:YAG laser. Regardless of the laser used, short pulse durations resulted in deeper incisions than long pulse durations. Concerning the distance, we found that to be effective, TFL had to be used in contact with the tissue. Finally, 365-μm fibers resulted in deeper incisions, while 550-μm fibers led to wider incisions and larger coagulation zones. Histological analysis revealed greater tissue penetration with the p-Tm:YAG laser compared to the TFL, while remaining less than with Ho:YAG. Its coagulation properties seem interesting insofar as it provides homogeneous coagulation without carbonisation, while incisions remained uniform without tissue laceration. Thus, the p-Tm:YAG laser appears to be an effective alternative to Ho:YAG and TFL lasers in prostate surgery.

Evolution of a late Quaternary succession by interpretation of high‐resolution seismic and bathymetric data, Adriatic Sea

AbstractThis paper presents the results of the interpretation of a set of high‐resolution seismic lines integrated with multibeam echosounder data acquired in a coastal area in the Northern Adriatic Sea. The aim of the study was to reconstruct the stratigraphic evolution of a late Quaternary sedimentary succession offshore the town of Bibione, North‐Eastern Italy, by recognising the key unconformities, identifying the main depositional units, dating them and reconstructing the depositional environments in relation to relative sea‐level variations. Specifically, four sedimentary units, separated by erosional unconformities associated with the development of deep channels, were identified and dated based on literature information. By interpreting the seismic data, sedimentary dynamics were reconstructed and palaeoenvironments identified. The lower unit corresponds to a paludal environment, showing abundant gas seeps and accumulations (bright spots); the two intermediate units correspond to fluvial deposits, filling the deep incisions that characterise the bounding surfaces. Finally, the shallowest unit, bounded by a wave‐ravinement surface incised by tidal currents, corresponds to the Holocenic progradation of the coastal wedge. In addition, several vertical gas chimneys were identified, ranging in width from a few metres to 20–30 m. These were present in all units, often reaching the sea floor. Finally, elongated mounds, about 300 m wide, at the sea floor were recognised. The bathymetric and seismic characteristics of these elongated bodies and their relationship to adjacent sedimentary bodies suggest that they are probably methane‐derived carbonate formations known as ‘Trezze’ or ‘Tegnùe’. These names recall the fact that the trawls of the local fishermen were often hindered (‘tegnù’ in the Venetian language) or even cut off by these formations.

The Anterior Branch of the Medial Femoral Cutaneous Nerve Innervates Cutaneous and Deep Surgical Incisions in Total Knee Arthroplasty.

Background/Objectives: The intermediate femoral cutaneous nerve (IFCN), the saphenous nerve, and the medial femoral cutaneous nerve (MFCN) innervate the skin of the anteromedial knee region. However, it is unknown whether the MFCN has a deeper innervation. This would be relevant for total knee arthroplasty (TKA) that intersects deeper anteromedial genicular tissue layers. Primary aim: to investigate deeper innervation of the anterior and posterior MFCN branches (MFCN-A and MFCN-P). Secondary aim: to investigate MFCN innervation of the skin covering the anteromedial knee area and medial parapatellar arthrotomy used for TKA. Methods: This study consists of (1) a dissection study and (2) unpublished data and post hoc analysis from a randomized controlled double-blinded volunteer trial (EudraCT number: 2020-004942-12). All volunteers received bilateral active IFCN blocks (nerve block round 1) and saphenous nerve blocks (nerve block round 2). In nerve block round 3, all volunteers were allocated to a selective MFCN-A block. Results: (1) The MFCN-A consistently innervated deeper structures in the anteromedial knee region in all dissected specimens. No deep innervation from the MFCN-P was observed. (2) Sixteen out of nineteen volunteers had an unanesthetized skin gap in the anteromedial knee area and eleven out of the nineteen volunteers had an unanesthetized gap on the skin covering the medial parapatellar arthrotomy before the active MFCN-A block. The anteromedial knee area and medial parapatellar arthrotomy was completely anesthetized after the MFCN-A block in 75% and 82% of cases, respectively. Conclusions: The MFCN-A shows consistent deep innervation in the anteromedial knee region and the area of MFCN-A innervation overlaps the skin area covering the medial parapatellar arthrotomy. Further trials are mandated to investigate whether an MFCN-A block translates into a clinical effect on postoperative pain after total knee arthroplasty or can be used for diagnosis and interventional pain management for chronic neuropathic pain due to damage to the MFCN-A during surgery.

Stacking pattern transition caused by submarine channel inception and internal levée development

ABSTRACTThe shift from highly amalgamated and laterally offset to aggradational and vertically stacked submarine channels is a pattern that has been widely recognized in seismic reflection datasets as well as in outcropping successions worldwide. However, the sedimentary and stratigraphic details of such an important part of channel evolution and its implications have not been discussed extensively. That gap is addressed here by characterizing a previously undocumented, seismic‐scale outcrop of the Tres Pasos Formation (Magallanes Basin, Chile) that records the transition from a laterally offset/low‐aggradational channel complex to a vertically stacked aggradational complex associated with the development of an internal levée that enhanced channel aggradation. The boundary between the two complexes is defined by a composite erosional surface (up to ca 35 m relief) with two adjacent element‐scale channelized incisions with contrasting sedimentary infills that provide unprecedented insight into this key phase of submarine channel evolution. Observations indicate that, in between these two depositional architecture styles, there is a significant phase of deep incision and bypass. The relief achieved via this deep incision of one or multiple simultaneously active conduits is interpreted to be necessary to set up the conditions for flow stripping and, subsequently, overbank deposition. Finally, the siltstone‐rich intra‐channel lithofacies association observed directly overlying part of the incision is interpreted to represent the stratigraphic expression of the earliest deposits of an active submarine channel preserved due to the abrupt abandonment of this pathway and the development of an adjacent conduit, which resulted in the former being covered with fine‐grained overbank deposits.

Buccal Fat Advancement-Transposition Flap for Reconstruction of Midface Volume Defects.

Background: The buccal fat pad (BFP) has previously been utilized for repair of various defects of the head and neck. Objectives: We explore the utility of a pedicled buccal fat advancement-transposition (BFAT) flap in various forms of midface reconstruction through a variety of surgical approaches and characterize its volume and axial reach in human anatomic specimens. Methods: Ten adult full-head human anatomic specimens were dissected, and a single surgical case demonstrating the use of a BFAT flap is described. Results: Nasolabial, subciliary, and deep plane facelift incisions all provided access to the BFP for use as a BFAT flap. The mean volume of mobilizable fat contained within a BFAT flap accessible through external incision was 7.1 cm3. Once fully mobilized, the externalized BFAT flap had a mean axial reach of 6.9 cm without tension. We also present a case illustrating the successful use of a BFAT flap for volumization of a large midface defect secondary to Mohs micrographic surgical resection of a cutaneous malignancy. Discussion: The BFAT flap, which exhibited substantial volume and reach in this study, can be harvested through multiple dissection windows or pre-existing defects and be used to reconstruct a variety of midface defects.

The effect of weathering in runoff-to-groundwater partitioning in the Island of Hawai'i: Perspectives for landscape evolution

We investigated how runoff-to-groundwater partitioning changes as a function of substrate age and degree of regolith development in the Island of Hawai'i, by modeling watershed-scale hydrodynamic properties for a series of volcanic catchments of different substrate age developed under different climates. In the younger catchments, rainfall infiltrates directly into the groundwater system and surface runoff is minimal, consisting of ephemeral streams flowing on the scale of hours to days. The older catchments show increasing surface runoff, with deeper incision and perennial discharge. We hypothesize that watershed-scale hydrodynamic properties change as a function of their weathering history—the convolution of time and climate: as surfaces age and become increasingly weathered, hydraulic conductivity is reduced, leading to increased runoff-to-recharge ratios. To test this relationship, we calculated both saturated hydraulic conductivity (k) and aquifer thickness (D) using recession flow analysis. We show that the average k in the younger catchments can be between 3 to 6 orders of magnitude larger than in older catchments, whereas modeled D increases with age. Ephemeral streams with zero baseflow at daily timescales cannot be evaluated using the same method. Instead, we calculated the recession constant for two contiguous catchments developed on young ash or lava deposits of different ages. Increasing bedrock age results in slower recession response in these ephemeral streams, which is consistent with decreasing hydraulic conductivity. Our results highlight the role of the weathering history in determining the evolution of watershed-scale hydrologic properties in volcanic catchments.

(097) 3 Year Follow Up After Modified Grid Incision and Sealing with Collagen Fleece for Treatment of Peyronie’s Disease

Abstract Introduction Previously, we introduced a less invasive modified technique by multiple grid incisions of Peyronie’s plaque. Objective To assess the efficacy of technique in 32 patients with 3 year follow-up. Methods From 2018, 32 patients with stable Peyronie’s disease were included with 3 major steps of surgery; 1) dissection of neurovascular bundle/urethra according to plaque location, 2) multiple deep grid incisions of plaque for complete correction of curvature/deformity, 3) sealing with TachoSil®. Prospectively, the stretched penile length (SPL), totally straightness, penile sono, erectile function at preoperative, and 6, 12, 24, 36 months postoperatively under approval of Institutional Review Board. Results Mean age was 59.2 years (46–72). Mean curvature was 53.5 (40–80) degree, 8 with hinge and 7 with hourglass deformity. IPP was inserted in 4 and 1 at postoperative 30 months for poor erectile function. Mean follow-up was 35.4 months (12–57). Daily massage softened the hard thickening of penis gradually from 3 months until 3 year. On follow-up sonography, subcutaneous thickening gradually decreased to near normal at 1–3 year and tunical breakage by grid incision reunited at postoperative 10–12 months. 2 patients immediately recurred dorsal curvature but most patients achieved totally straightness. Most patients gained preoperative length after 1.6 year. 96% of patients satisfied in GAQ at 2 year. Minor skin problem was occurred in two of IPP. Subcutaneous bulging hematoma was occurred in 3 patients but subsided in two within 3 months. One patients need revision surgery. In postoperative erectile function of 23 patients without IPP, spontaneous hard erection was recovered in 5 and the rest are satisfied with PED5 inhibitors. Conclusions Our prospective progress reports with technical modification of various plaque incisions shows that one can achieve a sufficient surgical effect without making defect of tunica albuginea but need long term follow up for 3 years at best. Disclosure No.

Two new species of Hesperopenna Medvedev & Dang, 1981 (Coleoptera, Chrysomelidae, Galerucinae) from Singapore.

Two new species of Hesperopenna Medvedev & Dang, 1981 are described from Singapore: H.temaseksp. nov. and H.bakerisp. nov. The specimens of both new species were collected by Charles Fuller Baker and found in the unidentified Galerucinae material deposited in the National Museum of Natural History, Smithsonian Institution, Washington, DC. Hesperopennatemaseksp. nov. is diagnosed by the black extreme elytral suture in the basal third, antennae longer than the body, the structure of the penis, and the last abdominal ventrite with two deep U-shaped incisions in females. Hesperopennabakerisp. nov. is diagnosed by the black tibia and first two tarsomeres, and the structure of the penis.

Investigating the efficacy of vacuum sealing drainage versus traditional negative pressure drainage in treating deep incision infections following posterior cervical internal fixation—a retrospective cohort study

BackgroundAssessing the efficacy and safety of Vacuum Sealing Drainage (VSD) in treating deep incision infections (DII) following posterior cervical internal fixation.MethodsWe retrospectively studied the clinical effects of VSD and Traditional Negative Pressure Drainage (TND) on 12 patients with deep incision infection after posterior cervical fixation surgery who were treated in our department from 2012 to 2020. A comparison of patient-related factors (age, gender, BMI, comorbidities, initial internal fixation surgery segment, preoperative laboratory inflammation indicators) and surgical-related factors (postoperative duration of fever, positive rate of drainage fluid bacterial culture, Visual Analogue Scale (VAS) score at 3 days after surgery, laboratory indicators at 3 days after surgery, debridement frequency and drainage time, hospital stay, internal fixation retention rate, and infection recurrence rate) between the VSD group and the TND group was conducted using independent sample t tests to draw experimental conclusions.ResultsThis study included 12 patients, with six cases of VSD (5 males and 1 female) and six cases of TND (4 males and 2 females). The VSD group had significantly lower postoperative fever time (1.50 ± 0.46 days vs. 4.28 ± 0.97 days, P < 0.05), a higher positive rate of bacterial cultures in drainage fluid (5/6 vs. 2/6, P < 0.05), lower 3 day VAS scores (3.13 ± 0.83 vs. 3.44 ± 0.88, P < 0.05), lower 3 day CRP levels (66.89 ± 23.65 mg/L vs. 57.11 ± 18.18 mg/L, P < 0.05), a shorter total drainage time (14.50 ± 2.98 days vs. 22.56 ± 3.01 days, P < 0.05), and a higher total drainage flow rate (395.63 ± 60.97 ml vs. 155.56 ± 32.54 ml, P < 0.05) than the TND group (the total drainage volume throughout the entire treatment process). In addition, the frequency of debridement (2.67 ± 0.52 times vs. 3.17 ± 0.41 times, P < 0.05) and average hospital stay (23.13 ± 3.27 days vs. 34.33 ± 6.86 days, P < 0.05) were significantly lower in the VSD group, although both groups retained internal fixation.ConclusionsVSD is a secure and effective treatment for deep incision infections that results from cervical posterior internal fixation surgery.

Surgical Site Infection in the General Surgery Department at the Fousseyni Daou Hospital in Kayes

Objectives: To determine frequency, analyze risk factors, identify responsible germs and antibiotic susceptibility, and assess the cost of infection. Patients and Method: We conducted a prospective study (August 1, 2022 to February 2023) for a period of 6 months. During our series, we received 250 patients who had been operated on and hospitalized in the general surgery department. The diagnosis of surgical site infection was based on criteria set forth by the Atlanta CDC. Data collection was carried out by interviewing, consulting records and anaesthesia sheets. Surgical wound monitoring was done up to the 30th postoperative day. A sample was taken for each infection. The word processor and tables were made on Microsoft Word 2019. Data were captured and analyzed on SPSS software (version 25). Results: We collected a total of 250 patients in our study. 31 developed an infection of the surgical site, a frequency of 12.4%. There were 31 patients, including 23 men and 8 women, with a mean age of 34 years, with a standard deviation of 20.75. The most common type of infection was superficial incision infection with 70.9% followed by deep incision infection with 29.1%. Risk factors for Surgical Site Infection Were: haemoglobin level; the nature of the surgery; ALTEMEIR contamination class 3 and 4; NNISS index 1 and 2; the type of intervention with probability tests P&lt;0.05. The analysis of the 31 samples resulted in 31 positive cultures, i.e. a bacteriological yield of 100%. Echerichia coli was the most isolated germ with 25.8%, followed by Enterobacter cloacae 19.3% and Enterococcus 19.3%. The Treatment was: Carrying out local care based on antiseptics (dakin; Betadine; hydrogen peroxide) and general (adapt to susceptibility testing). The consequence of surgical site infection was the prolongation of the hospital stay by an average of 19 days for infected patients; with an estimated additional cost of 294712 and 0% mortality.

Topical Losartan Inhibition of Myofibroblast Generation in Rabbit Corneas With Acute Incisions.

The purpose of this study was to study whether deep central corneal incisions close during topical losartan treatment and the effect of topical losartan on myofibroblast generation after incisions in rabbit corneas. Rabbits (12) had a 0.35-mm deep radial incision from the center of the cornea into the limbus in 1 eye that was approximated with a single 10-0 nylon suture 1 mm inside the limbus. The incision was treated with 50 μL of topical 0.8 mg/mL losartan or 50 μL of balanced salt solution vehicle 6 times per day for 1 month. Standardized slitlamp photographs of the central incisions were analyzed for opacity with ImageJ before euthanasia. Triplex IHC was performed on cryofixed corneas for myofibroblast marker alpha-smooth muscle actin, mesenchymal cell marker vimentin, and basement membrane marker laminin alpha-5. Stromal α-SMA-positive myofibroblasts surrounding the incisions were quantitated with ImageJ. Topical losartan compared with vehicle did not affect closure of the radial incisions or the opacity that developed surrounding the incisions at 1 month after injury. Topical losartan compared with vehicle did significantly decrease the average density of stromal myofibroblasts surrounding the incisions. Topical losartan, a known inhibitor of transforming growth factor beta signaling, did not affect closure of deep corneal incisions. Losartan decreased myofibroblast generation surrounding nearly full-thickness radial corneal incisions compared with vehicle. The opacity at the incisions was not significantly affected by losartan-likely because corneal fibroblasts that develop in the stroma adjacent to the incisions were not changed by the losartan compared with the vehicle.

IL-33/ST2 induces macrophage-dependent ROS production and TRPA1 activation that mediate pain-like responses by skin incision in mice.

Background: Insufficiently managed incisional (INC) pain severely affects patients' life quality and rehabilitation after a major operation. However, mechanisms underlying INC pain still remain poorly understood. Methods: A mouse model of INC pain was established by skin plus deep muscle incision. Biochemistry assay, in vivo reactive oxygen species (ROS) imaging, Ca2+ imaging combined with retrograde labelling, neuron tracing and nocifensive behavior test, etc. were utilized for mechanism investigation. Results: We found pro-nociceptive cytokine interleukin -33 (IL-33) ranked among top up-regulated cytokines in incised tissues of INC pain model mice. IL-33 was predominantly expressed in keratinocytes around the incisional area. Neutralization of IL-33 or its receptor suppression of tumorigenicity 2 protein (ST2) or genetic deletion of St2 gene (St2 -/-) remarkably ameliorated mechanical allodynia and improved gait impairments of model mice. IL-33 contributes to INC pain by recruiting macrophages, which subsequently release ROS in incised tissues via ST2-dependent mechanism. Transfer of excessive macrophages enhanced oxidative injury and reproduced mechanical allodynia in St2 -/- mice upon tissue incision. Overproduced ROS subsequently activated functionally up-regulated transient receptor potential ankyrin subtype-1 (TRPA1) channel innervating the incisional site to produce mechanical allodynia. Neither deleting St2 nor attenuating ROS affected wound healing of model mice. Conclusions: Our work uncovered a previously unrecognized contribution of IL-33/ST2 signaling in mediating mechanical allodynia and gait impairment of a mouse model of INC pain. Targeting IL-33/ST2 signaling could be a novel therapeutic approach for INC pain management.

Holocene sedimentary history of the Silala River (Antofagasta Region, Chile)

AbstractAssessing past and ongoing climate change in the central Andes is critical for understanding the impact of future environmental changes under anthropogenic warming. Emerging from springs located in Bolivia and flowing into northern Chile's Atacama Desert, the Silala River contains inset, terraced wetland (or in‐stream) deposits that provide a unique opportunity to study the impact of past hydroclimate change in a sensitive groundwater system with a small catchment area. After an initial (late Pleistocene) period of deep incision to form the present ravine, in‐stream wetland fine‐grained deposits formed during three phases of aggradation dated to &gt;8.5–1.9 ka (Unit 1), &gt;0.65–0.2 ka (Unit 2), and &lt;0.2 ka to the recent 20th century (Unit 4). These phases of accumulation were coeval with periods of well‐dated records of elevated groundwater tables throughout northern Chile. Phases of abrupt downcutting occurred due to a lowering of the water table after 1.9 ka and before 0.2 ka. The cycle of erosion and deposition clearly continues to the present as evinced by the very recent (21st century) incision of Unit 4 (&gt;1.5 m in some areas) throughout sectors of the Silala where dried‐out standing vegetation can be seen. Such recent incision may be due to multiple different factors, including recent climate change coupled with intense extraction of groundwater resources by the copper mining industry.This article is categorized under: Human Water &gt; Water Governance Science of Water &gt; Hydrological Processes Science of Water &gt; Water and Environmental Change

Linear shaped-charge jet optimization using machine learning methods

Linear shaped charges are used to focus energy into rapidly creating a deep linear incision. The general design of a shaped charge involves detonating a confined mass of high explosive (HE) with a metal-lined concave cavity on one side to produce a high velocity jet for the purpose of striking and penetrating a given material target. This jetting effect occurs due to the interaction of the detonation wave with the cavity geometry, which produces an unstable fluid phenomenon known as the Richtmyer–Meshkov instability and results in the rapid growth of a long narrow jet. We apply machine learning and optimization methods to hydrodynamics simulations of linear shaped charges to improve the simulated jet characteristics. The designs that we propose and investigate in this work generally involve modifying the behavior of the detonation waves prior to interaction with the liner material. These designs include the placement of multiple detonators and the use of metal inclusions within the HE. We are able to produce a linear shaped-charge design with a higher penetration depth than the baseline case that we consider and accomplish this using the same amount of or less HE.

Morphology, seismic stratigraphy, and tectonic control of the Yitong submarine canyons – fan apron system in the northern South China Sea

Submarine fans are ubiquitous in modern deep-water environments. Such systems reported in the literature are largely fed by shelf-indented canyons receiving ample fluvial or longshore drift sediment inputs, whereas those nourished by slope-confined canyons far away from terrigenous sediment sources remain poorly understood. Herein, we report such a system, the Yitong submarine canyons – fan apron system (YCFS), from the northern South China Sea. This system was studied using multibeam bathymetric and two-dimensional multichannel seismic data, combined with geological constraints from nearby International Ocean Discovery Program drilling sites. YCFS consists of approximately 12 submarine canyons confined in the lower continental slope of >1200 m water depth, which feed a fan apron in the connecting abyssal plain. The canyons are erosion-dominated, as evidenced by their V-shaped cross-sections with up to 708 m deep incisions. Canyon infillings comprise mass transport deposits and turbidites, and interfluves exhibit features such as landslides, creep-typed sediment waves, and gullies, indicating the canyons and interfluves are dominated by mass transport and turbidity-current processes. The fan apron is generally depositional, in which channels and channel-levee complexes, turbidite lobes, and mass transport deposits comprise the main depositional elements. In the canyon-to-fan transitions, supercritical turbidity current features and bedforms, including plunge pools and connected sediment mounds, cyclic steps, and antidunes, are developed, which are linked to the deceleration and hydraulic-jump effects of the high-velocity turbidity currents shedding off the canyons. Seismic stratigraphic analysis revealed that YCFS was initiated in Late Miocene. The formation and maintenance of YCFS are linked to the long-term existence of an upslope margin-parallel basement high. The latter could have maintained a steep slope condition (up to 6.5°) that favors the development of canyons and supercritical turbidity currents. Because of the blocking effect of the basement high, YCFS receives limited supply of the shallow-water sediments.

Pleural Drain Insertion: Surgical Technique, Aftercare, and Removal

Pleural drain insertion is a commonly employed technique used for several indications, including the drainage of haemothorax and pneumothorax. Difficulties can be encountered without proper techniques, especially in obese patients. We describe and illustrate our stepwise approach used during chest drain insertion. The points emphasised include: appropriate use of sedation, use of local anaesthetics, pleural anaesthesia, making a deep incision in the intercostal space, using a proper size and type of haemostat to enter the pleura and dilate the tract, blunt dissection with a finger, using the haemostat to ensure basal or apical placement of the drain, fixation of the drain with a vertical mattress suture to secure the tube, and placing the drain on suction for effective evacuation of the pleural cavity. Insertion of a “surgical” drain requires special techniques and precautions to ensure safe and effective drainage of the pleural cavity. Ultrasound may also be utilised to aid drain placement. Understanding the “bubble and swing” after insertion is also explained in simple terms to guide aftercare of the drain and indications for removal. A description of a “clamp test” to guide the decision for removal, if required, is included. The evidence for optimal timing of removal in the respiratory cycle is also reviewed and explained in a stepwise approach with practical tips for patient counselling.

Active Deformation Pattern in the Western Flank of the Central Taurides, Southern Margin of the Central Anatolian Plateau: Inferences From Geomorphic Markers and Kinematic Indicators

AbstractThe southwestern margin of the Central Anatolian Plateau corresponds to the upper crust of the subduction between African and Anatolian plates, with a high relief of up to 2 km. This mountainous region has distinctive geomorphological features and presents a unique setting to investigate the mechanism of orogenic plateau margin development related to subduction and topographic evolution around the Eastern Mediterranean. We present new kinematic data from exposed fault planes and tectonic landforms from high‐resolution digital elevation models to elucidate the deformation pattern and its relation with the crustal deformation. We evaluate the deformation pattern based on the spatial distribution of kinematic analyses and geomorphic markers like low relief upland surfaces, disrupted karst basins, knickpoints, and deep bedrock incisions from watershed to shoreline. Our geomorphic analysis reveals a post‐orogenic transient actively deforming topography. The geomorphic markers constrain long‐term surface uplift pattern with a mean cumulative surface uplift of 1,710 ± 50 m and shows an increasing trend from west to east, from 1,600 ± 50 to 1,800 ± 50 m. Our results suggest a dome‐like uplift pattern in the west‐east direction across the southern margin that reaches up to maximum cumulative uplift values in the quadrangle of Alanya‐Başyayla‐Ermenek‐Gazipaşa. Our kinematic measurements along the youngest generation of faults revealed an active NE‐SW extensional deformation across a broad 200 km zone in the north of the subduction. Our findings have significant implications for understanding the morphotectonic evolution and post‐orogenic deformation in the plateau margins and geodynamic evolution of the Eastern Mediterranean.