CO2 laser

Cell separation using microfluidics has become an effective method to isolate biological contaminants from bodily fluids and cell cultures, such as isolating bacteria contaminants from microalgae cultures and isolating bacteria contaminants from white blood cells. In this study, bacterial cells were used as a model contaminant in microalgae culture in a passive microfluidics device, which relies on hydrodynamic forces to demonstrate the separation of microalgae from bacteria contaminants in U and W-shaped cross-section spiral microchannel fabricated by defocusing CO2 laser ablation...

Mid-infrared laser excitation of molecules into high-lying vibrational states offers a novel route to realize controlled ground-state chemistry. Here we successfully demonstrate vibrational ladder climbing in the antisymmetric stretch of CO2 in the condensed phase by using intense down-chirped mid-infrared pulses. Spectrally resolved pump-probe measurements directly observe excited-state absorptions attributed to vibrational populations up to the v = 9 state, whose corresponding energy of 2.5 eV is 46% of the dissociation energy...

OBJECTIVE: To evaluate the penetration of a dye in root dentin after activation with different laser wavelengths. MATERIALS: Palatal roots of 38 human molars were enlarged and disinfected. Irrigation activation was performed with an Er:YAG laser: @50 mJ, 15 Hz (Er:YAG); a 9.3 µm CO2 laser: @40% power (CO2 ); diode lasers 455 nm/970 nm: @0.8 W, 15 Hz (D455, D970) and 808/980 nm: @1 W (D808, D980) and compared to positive control: etching with 35% H3 PO4 (POS); negative control: water (NEG) and conventional needle irrigation: NaOCl and ethylenediaminetetraacetic acid (EDTA) (CONV)...

OBJECTIVES: To assess the value of carbon dioxide transoral laser microsurgery (CO2 TOLMS) for early-stage glottic cancer with special regard to involvement of the anterior commissure (AC). STUDY DESIGN: Single-center retrospective cohort study. SETTING: Grade-A tertiary hospital. METHODS: A retrospective analysis of patients with early-stage (Tis-T2) glottic cancer who underwent CO2 TOLMS. All patients had at least 2 years of follow-up...

To investigate the in vivo and in situ effect of different types of lasers in prevention of enamel demineralization in high caries risk cases (around orthodontic brackets, around restoration and in caries susceptible pits and fissures). PubMed was searched using the following keyword sequence; (Laser therapy OR laser irradiation OR laser application) AND (enamel caries prevention OR enamel demineralization OR enamel remineralization OR early enamel caries OR early-enamel caries OR enamel resistance OR enamel decalcification OR white spot lesions WSLs OR incipient lesion OR enamel decay OR enamel Dissolution OR enamel microhardness) AND (clinical trial OR Randomized clinical trial OR In situ study)...

BACKGROUND: Oral leukoplakia (OLK) is a prevalent precancerous lesion with limited non-pharmacological treatment options. Surgery and various lasers are the mainstay of treatment; however, their relative efficacy and optimal choice remain unclear. This first network meta-analysis compared the effects of different lasers and surgical excision on post-treatment recurrence and comfort in OLK patients. METHODS: We searched four databases for relevant randomized controlled trials (RCTs) up to April 2023...

Herein, a strategy to stamp laser-produced reduced graphene oxide (rGO) onto flexible polymers using only office-grade tools, namely, roll-to-roll thermal stamping, is proposed, proving for the first time its effectiveness for direct bioelectrocatalysis. This straightforward, scalable, and low-cost approach allows us to overcome the limits of the integration of laser-induced rGO-films in bioanalytical devices. Laser-produced rGO has been thermally stamped (TS) onto different polymeric substrates (PET, PVC, and EVA) using a simple roll-laminator; the obtained TS-rGO films have been compared with the native rGO (untransferred) via morphochemical and electrochemical characterization...

The practical application of flexible pressure sensors, including electronic skins, wearable devices, human-machine interaction, etc., has attracted widespread attention. However, the linear response range of pressure sensors remains an issue. Ecoflex, as a silicone rubber, is a common material for flexible pressure sensors. Herein, we have innovatively designed and fabricated a pressure sensor with a gradient micro-cone architecture generated by CO2 laser ablation of MWCNT/Ecoflex dielectric layer film. In cooperation with the gradient micro-cone architecture and a dielectric layer of MWCNT/Ecoflex with a variable high dielectric constant under pressure, the pressure sensor exhibits linearity (R2 = 0...

Laser Sintering (LS) is a type of Additive Manufacturing (AM) exploiting laser processing of polymeric particles to produce 3D objects. Because of its ease of processability and thermo-physical properties, polyamide-12 (PA-12) represents ~95% of the polymeric materials used in LS. This constrains the functionality of the items produced, including limited available colours. Moreover, PA-12 objects tend to biofoul in wet environments. Therefore, a key challenge is to develop an inexpensive route to introduce desirable functionality to PA-12...

OBJECTIVES: Postoperative evaluations of patients, who undergo of transoral thyroarytenoid myoneurectomy using CO2 laser for the treatment of Adductor Spasmodic Dysphonia (ASD), reveal some residual laryngeal symptoms such as intermittent spasms, vocal effort, and stiffness in laryngeal muscles which can be identified on videolaryngo-stroboscopy (VLS) by patterns of Muscle Tension Dysphonia (MTD) and mucosal wave, and as deviations in acoustic perceptual measures. This study aims to document these vocal symptoms observed postoperatively, and most importantly highlight the need for voice therapy postoperatively and report the short-term vocal outcomes post-therapy...

Stress urinary incontinence (SUI) affects around 20% of women. In addition to the established suburethral sling insertion, two less invasive approaches are of interest today: urethral bulking agents and vaginal laser therapy. This review discusses articles through December 2023 identified by a PubMed literature search using the keywords "incontinence" and "bulking" or "laser". Although the two approaches are less effective than sling insertions, there are specific conditions in which one or the other technique is more advantageous...

Fused silica was polished to a high quality by a CO2 laser beam with a rapid scanning rate. The rapid scanning rate produced a line laser heat source, resulting in a "polishing line" during the polishing process. The Taguchi method was used to evaluate the comprehensive influence of polishing process parameters on the polishing qualities. Four factors, namely the length of laser reciprocating scanning (A), laser beam scanning speed (B), feed speed (C), and defocusing amount (D), were investigated in this study...

Objective: Assessment of different remineralizing pretreatment casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), proanthocyanidin (PA), carbon dioxide laser (CO2 ), eggshell solution (ES) on the shear bond strength (SBS) of resin composite bonded to remineralized carious-affected dentin (CAD). Materials and methods: Eighty human molars were collected with occlusal caries that extended about halfway into the dentin. Using a water-cooled, low-speed cutting saw, a flat, mid-coronal dentin surface was exposed...

BACKGROUND: Keloids are benign proliferative scars that form as a result of dysregulated growth and collagen deposition in response to cutaneous injury. Laser therapies have emerged as promising options for the treatment of keloids, with performance varying by laser type and lesion characteristics. PURPOSE: To assess the combined continuous wave and repetitive fractionated CO2 laser treatment of keloids. METHODS: A retrospective chart review of 22 cases of keloid scars treated with combined CO2 laser modes...

BACKGROUND: Scarring is one of the most prevalent long-term complications of acne vulgaris and has cosmetic, psychological, and social burdens. Contemporary management programs integrate multiple modalities to best address the multiple factors underlying their development and persistence. This work assessed the impact of sequential multimodal laser therapy on acne scar geometrics and texture. METHODS: Adult patients (n = 16) with Fitzpatrick skin type II-IV and presenting with facial acne scars, underwent three combination ablative (CO2 ), and nonablative (1570 nm) laser treatment sessions at two-month intervals...

Objective: This in vitro study evaluates the shear bond strength (SBS) of yttria-stabilized tetragonal zirconia (Y-TZP) and resin cement after different surface treatments. Materials and methods: Forty-eight ceramic cubes were divided into four groups ( n  = 12): G1 (control) sandblasting with Al2 O3 ; G2-sandblasting with silica-coated Al2 O3 (Rocatec); G3-Rocatec + CO2 laser; and G4-CO2 laser + Rocatec. A metallic primer was applied to the pretreated ceramic. A rubber ring was adapted on the central area, and then, the resin cement was inserted into the matrix and photoactivated...

OBJECTIVE: To compare clinical outcomes in patients with and without history of tobacco use who underwent Zenker's diverticulotomy (ZD). STUDY DESIGN: Single institution retrospective review. SETTING: Tertiary care academic hospital. METHODS: A retrospective review of patients who underwent ZD via an open stapler, rigid endoscopic CO2 laser, stapler or harmonic scalpel, and flexible endoscopic technique from January 2006 to December 2020 was performed...

BACKGROUND: Nail psoriasis poses challenges for effective treatment, and topical drug delivery through the nail plate is limited. A novel approach to address this challenge involves the use of ablative fractional laser as a pretreatment strategy to enhance topical drug delivery for nail psoriasis. SUMMARY: This systematic review, conducted in accordance with PRISMA guidelines, involved an extensive literature search across PubMed/MEDLINE, EMBASE, and the Cochrane Library up to July 2023...

Warts are caused by human papillomavirus (HPV) infection and can involve multiple parts of skin and mucosa, of which periungual and subungual warts are the most difficult to treat. Periungual or subungual wart is verruca vulgaris growing around or under the fingernail, destroying and deforming the nail and nail bed. Currently, liquid nitrogen cryotherapy and CO2 laser are often used for the treatment. Clinically, few doctors routinely use photodynamic therapy (PDT) to treat viral warts. We used PDT combined with liquid nitrogen cryotherapy and curettage to successfully treat a case of intractable periungual and subungual warts...

An integrated path differential absorption (IPDA) lidar can accurately measure regional C O 2 weighted column average concentrations ( X C O 2 ), which are crucial for understanding the carbon cycle in climate change studies. To verify the performance and data inversion methods of space-borne IPDA lidar, in July 2021, we conducted an airborne lidar validation experiment in Dunhuang, Gansu Province, China. An aircraft was equipped with a lidar system developed to measure X C O 2 and an in situ greenhouse gas analyzer (GGA)...