The use of light energy to drive carbon dioxide (CO₂) reduction for production of chemicals is of great significance for relieving environmental pressure and solving energy crisis. Photocapture, photoelectricity conversion and CO₂ fixation are the key factors affecting the efficiency of photosynthesis, and thus also affect the efficiency of CO₂ utilization. To solve the above problems, this review systematically summarizes the construction, optimization and application of light-driven hybrid system from the perspective of combining biochemistry and metabolic engineering. We introduce the latest research progress of light-driven CO₂ reduction for biosynthesis of chemicals from three aspects: enzyme hybrid system, biological hybrid system and application of these hybrid system. In the aspect of enzyme hybrid system, many strategies were adopted such as improving enzyme catalytic activity and enhancing enzyme stability. In the aspect of biological hybrid system, many methods were used including enhancing biological light harvesting capacity, optimizing reducing power supply and improving energy regeneration. In terms of the applications, hybrid systems have been used in the production of one-carbon compounds, biofuels and biofoods. Finally, the future development direction of artificial photosynthetic system is prospected from the aspects of nanomaterials (including organic and inorganic materials) and biocatalysts (including enzymes and microorganisms).
Carbon Dioxide/metabolism* ; Photosynthesis ; Metabolic Engineering

The current linear economy model relies on fossil energy and increases CO₂ emissions, which contributes to global warming and environmental pollution. Therefore, there is an urgent need to develop and deploy technologies for carbon capture and utilization to establish a circular economy. The use of acetogens for C1-gas (CO and CO₂) conversion is a promising technology due to high metabolic flexibility, product selectivity, and diversity of the products including chemicals and fuels. This review focuses on the physiological and metabolic mechanisms, genetic and metabolic engineering modifications, fermentation process optimization, and carbon atom economy in the process of C1-gas conversion by acetogens, with the aim to facilitate the industrial scale-up and carbon negative production through acetogen gas fermentation.
Fermentation ; Gases/metabolism* ; Carbon Dioxide/metabolism* ; Metabolic Engineering ; Carbon/metabolism*

To comprehensively evaluate the human body's respiratory, circular metabolism and other functions, and to diagnose lung disease, an accurate and reliable pulmonary function test (PFT) is developed. The system is divided into two parts:hardware and software. It realizes the collection of respiratory, pulse oxygen, carbon dioxide, oxygen and other signals, and draws flow-volume curve (FV curve), volume-time curve (VT curve), respiratory waveform, pulse wave, carbon dioxide and oxygen waveform in real time on the upper computer of the PFT system, and conducts signal processing and parameter calculation for each signal. The experimental results prove that the system is safe and reliable, it can accurately measure the basic functions of human body, and provide reliable parameters, and has good application prospects.
Humans ; Carbon Dioxide ; Respiratory Function Tests ; Oxygen ; Heart Rate

Carbon dioxide is a simple asphyxial gas, with low concentrations having an excitatory effect on the respiratory center, while high concentrations have an inhibitory effect on the respiratory center. Simple carbon dioxide poisoning is rarely seen clinically. This article reviews and analyzes the treatment process of 9 cases of acute inhalation carbon dioxide poisoning in a cargo ship carbon dioxide leakage accident in May 2019, summarizes clinical treatment experience, and provides timely and effective treatment for acute pulmonary edema caused by acute inhalation carbon dioxide poisoning. In particular, the application of hormones has a good prognosis, improving clinicians' understanding of the disease.
Humans ; Carbon Dioxide ; Ships ; Accidents ; Pulmonary Edema ; Treatment Outcome ; Poisoning ; Accidents, Occupational

OBJECTIVE: To investigate the association between short-term exposure to indoor total volatile organic compounds (TVOC) and nocturnal heart rate variability (HRV) among young female adults. METHODS: This panel study recruited 50 young females from one university in Beijing, China from December 2021 to April 2022. All the participants underwent two sequential visits. During each visit, real time indoor TVOC concentration was monitored using an indoor air quality detector. The real time levels of indoor temperature, relative humidity, noise, carbon dioxide and fine particulate matter were monitored using a temperature and humidity meter, a noise meter, a carbon dioxide meter and a particulate counter, respectively. HRV parameters were measured using a 12-lead Holter. Mixed-effects models were used to evaluate the association between the TVOC and HRV parameters and establish the exposure-response relationships, and two-pollutant models were applied to examine the robustness of the results. RESULTS: The mean age of the 50 female subjects was (22.5±2.3) years, and the mean body mass index was (20.4±1.9) kg/m². During this study, the median (interquartile range) of indoor TVOC concentrations was 0.069 (0.046) mg/m³, the median (interquartile range) of indoor temperature, relative humidity, carbon dioxide concentration, noise level and fine particulate matter concentration were 24.3 (2.7) ℃, 38.5% (15.0%), 0.1% (0.1%), 52.7 (5.8) dB(A) and 10.3 (21.5) μg/m³, respectively. Short-term exposure to indoor TVOC was associated with significant changes in time-domain and frequency-domain HRV parameters, and the exposure metric for most HRV parameters with the most significant changes was 1 h-moving average. Along with a 0.01 mg/m³ increment in 1 h-moving average concentration of indoor TVOC, this study observed decreases of 1.89% (95%CI: -2.28%, -1.50%) in standard deviation of all normal to normal intervals (SDNN), 1.92% (95%CI: -2.32%, -1.51%) in standard deviation of average normal to normal intervals (SDANN), 0.64% (95%CI: -1.13%, -0.14%) in percentage of adjacent NN intervals differing by more than 50 ms (pNN50), 3.52% (95%CI: -4.30%, -2.74%) in total power (TP), 5.01% (95%CI: -6.21%, -3.79%) in very low frequency (VLF) power, and 4.36% (95%CI: -5.16%, -3.55%) in low frequency (LF) power. The exposure-response curves showed that indoor TVOC was negatively correlated with SDNN, SDANN, TP, and VLF when the concentration exceeded 0.1 mg/m³. The two-pollutant models indicated that the results were generally robust after controlling indoor noise and fine particulate matter. CONCLUSION Short-term exposure to indoor TVOC was associated with significant negative changes in nocturnal HRV of young women. This study provides an important scientific basis for relevant prevention and control measures.
Humans ; Female ; Adult ; Young Adult ; Air Pollutants/analysis* ; Heart Rate/physiology* ; Volatile Organic Compounds/analysis* ; Carbon Dioxide ; Particulate Matter/adverse effects* ; Environmental Pollutants

Introduction: Laparoscopic Cholecystectomy uses carbon dioxide (CO2) which affects the respiratory, cardiovascular and renal system. The residual CO2 induces phrenic nerve irritation, manifesting as shoulder and abdominal pain. Recruitment maneuvers opens the lungs and helps expelling this residual carbon dioxide. However, there are limited studies on its role to hemodynamics especially in patients undergoing abdominal laparoscopic procedures. Methods: Sixty patients (51 15.1) scheduled for laparoscopic cholecystectomy under General Endotracheal Anesthesia were randomly allocated to two groups. The control group (Group C) underwent standard laparoscopic cholecystectomy procedures. The experimental group (Group R) was placed in a Trendelenburg and was given 4-5 manual pulmonary inflations at a pressure of 40cmH20. The blood pressure, heart rate, respiratory rate and oxygen saturation, as well as the post operative site pain and shoulder pain were measured using the Numerical Pain Scale (NPS) were monitored at 0, 1 and 2 hours post operatively. Results: The demographics and preoperative vital signs were comparable. The mean systolic blood pressure [119.5 vs 131.5; p=0.002], mean arterial pressure [91.8 vs 95.3; p=0.049], heart rate [74.9 vs 87.5; p <0.001] and respiratory rate [15.7 vs 16.2; p=0.02] were all differrent only during the immediate post operative period. The mean shoulder pain was lower in Group R immediately [1.9 ± 1.2; p=0.01] and 1 hour after surgery [0.7 ± 0.8; p=0.01]. Conclusion Recruitment maneuver significantly reduces the shoulder pain scores after laparoscopic cholecystectomy. It causes a decrease in blood pressure, heart rate and mean arterial pressure in the immediate post operative period.
Cholecystectomy, Laparoscopic ; Shoulder Pain ; Hemodynamics ; Carbon Dioxide

Extracorporeal carbon dioxide removal is an artificial lung auxiliary technique based on extrapulmonary gas exchange and can effectively remove carbon dioxide and provide oxygenation to a certain extent, and it is one of the effective treatment techniques for hypercapnia developed after mechanical ventilation and extracorporeal membrane oxygenation in recent years and has wide application prospect. This article elaborates on the development, working principle, advantages, classification, complications, and clinical application of extracorporeal carbon dioxide removal, so as to provide a new choice for extracorporeal carbon dioxide removal in clinical practice.
Humans ; Carbon Dioxide ; Extracorporeal Membrane Oxygenation ; Renal Dialysis ; Respiration, Artificial

Objective: To explore the clinical effects of fractional carbon dioxide laser combined with minimally invasive scar release in the treatment of post-acne atrophic scars. Methods: A retrospectively observational study was conducted. From January to June 2021, 60 patients with grade 3 and 4 post-acne atrophic scars who met the inclusion criteria were admitted to the First Affiliated Hospital of Henan University of Traditional Chinese Medicine. According to the adopted treatment methods, 30 patients treated with fractional carbon dioxide laser combined with minimally invasive scar release were included in combined treatment group (19 males and 11 females, aged (26±4) years), and 30 patients treated with fractional carbon dioxide laser alone were included in laser alone group (18 males and 12 females, aged (25±6) years). All the patients received the treatment once every two months, totally 3 times. Before the first treatment and 2 months after the last treatment, the scars were assessed by échelle d'évaluation clinique des cicatrices d'acné (ECCA). In 2 months after the last treatment, the curative effect was evaluated and the total effective rate was calculated according to the ECCA score. The adverse reactions of patients during the treatment were recorded. Data were statistically analyzed with independent sample t test, Wilcoxon rank-sum test, Mann-Whitney U test, chi-square test, and Fisher's exact probability test. Results: Before the first treatment, the ECCA scores of patients in the two groups were similar (P>0.05). In 2 months after the last treatment, the ECCA scores of patients in combined treatment group were significantly lower than those of laser alone group (Z=-2.89, P<0.05). The ECCA scores of patients in combined treatment group and laser alone group in 2 months after the last treatment were both significantly lower than those before the first treatment (with Z values of -4.81 and -4.79, respectively, P<0.05). In 2 months after the last treatment, the treatment in laser alone group cured the scars in 2 patients, and were markedly effective in 13 patients, effective in 7 patients, and ineffective in 8 patients; the treatment in combined treatment group cured the scars in 4 patients, and were markedly effective in 22 patients, effective in 3 patients, and ineffective in one patients. The total effective rate of scar treatment in combined treatment group (96.67%, 29/30) was significantly higher than 73.33% (22/30) in laser alone group (P<0.05). During treatment, in combined treatment group, 3 patients had pain, one patient had redness and swelling, and one patient had pigmentation. In laser alone group, one patient had pain, and 2 patients had pigmentation. No infection occurred in the wounds of all the patients in the two groups. Conclusions: Compared with fractional carbon dioxide laser alone, fractional carbon dioxide laser combined with minimally invasive scar release for post-acne atrophic scars can result in a higher total effective rate, with simple operation and good effect, so it is worthy of clinical application.
Male ; Female ; Humans ; Cicatrix/therapy* ; Retrospective Studies ; Treatment Outcome ; Lasers, Gas/therapeutic use* ; Acne Vulgaris ; Atrophy ; Pain ; Carbon Dioxide

OBJECTIVE: To evaluate the effect of transcutaneous acupoint electrical stimulation (TEAS) at Neiguan (PC 6) on general anesthesia under preserving spontaneous breathing in thoracoscopic lobectomy. METHODS: A total of 66 patients of primary lung cancer undergoing thoracoscopic lobectomy were divided to an observation group (33 cases, 1 case discontinued) and a control group (33 cases). In the observation group, TEAS at Neiguan (PC 6) was used 30 min before anesthesia induction till the end of surgery. The surgery time, maximum value of partial pressure of end-tidal carbon dioxide (P_ETCO₂) and minimum value of oxygen saturation (SpO₂) of the two groups were recorded. The dosage of propofol, sufentanil, remifentanil and dexmedetomidine were analyzed. Separately, before induction (T₀), at the start of surgery (T₁), thoracic exploration (T₂) and lobectomy (T₃), as well as 30 min (T₄) and 60 min (T₅) after lobectomy, the mean arterial pressure (MAP), heart rate (HR), respiratory rate (RR), serum cortisol (Cor) and norepinephrine (NE) were measured. The time of post anesthesia care unit (PACU) stay, ambulation, flatus, chest drainage and the incidence of nausea and vomiting were compared between the two groups. RESULTS: The maximum value of P_ETCO₂, the dosage of propofol and remifentanil in the observation group were lower than those in the control group (P < 0.05, P < 0.01), the minimum value of SpO₂ in the observation group was higher than that of the control group (P < 0.01). At T₁-T₅, the MAP, HR, serum Cor and NE levels in the observation group were all lower than those in the control group (P < 0.05). The ambulation time, the time for the flatus, chest drainage time, and the incidence of nausea and vomiting in the observation group were all lower than those in the control group (P<0.001, P < 0.01). CONCLUSION For the general anesthesia under preserving spontaneous breathing in thoracoscopic surgery, TEAS at Neiguan (PC 6) relieves stress response, reduces opioids dosage and promotes postoperative recovery.
Humans ; Acupuncture Points ; Carbon Dioxide ; Flatulence ; Propofol ; Remifentanil ; Anesthesia, General ; Nausea ; Norepinephrine ; Electric Stimulation

OBJECTIVE: To analyze the effect of mechanical cardiopulmonary resuscitation (CPR) on patients with cardiac arrest with the vertical spatial pre-hospital emergency transport. METHODS: A retrospective cohort study was conducted. The clinical data of 102 patients with out-of-hospital cardiac arrest (OHCA) who were transferred to the emergency medicine department of Huzhou Central Hospital from the Huzhou Emergency Center from July 2019 to June 2021 were collected. Among them, the patients who performed artificial chest compression during the pre-hospital transfer from July 2019 to June 2020 served as the control group, and the patients who performed artificial-mechanical chest compression (implemented artificial chest compression first, and implemented mechanical chest compression immediately after the mechanical chest compression device was ready) during pre-hospital transfer from July 2020 to June 2021 served as the observation group. The clinical data of patients of the two groups were collected, including basic data (gender, age, etc.), pre-hospital emergency process evaluation indicators [chest compression fraction (CCF), total CPR pause time, pre-hospital transfer time, vertical spatial transfer time], and in-hospital advanced resuscitation effect evaluation indicators [initial end-expiratory partial pressure of carbon dioxide (P_ETCO₂), rate of restoration of spontaneous circulation (ROSC), time of ROSC]. RESULTS: Finally, a total of 84 patients were enrolled, including 46 patients in the control group and 38 in the observation group. There was no significant difference in gender, age, whether to accept bystander resuscitation or not, initial cardiac rhythm, time-consuming pre-hospital emergency response, floor location at the time of onset, estimated vertical height, and whether there was any vertical transfer elevator/escalator, etc. between the two groups. In the evaluation of the pre-hospital emergency process, the CCF during the pre-hospital emergency treatment of patients in the observation group was significantly higher than that in the control group [69.05% (67.35%, 71.73%) vs. 61.88% (58.18%, 65.04%), P < 0.01], the total pause time of CPR was significantly shorter than that in the control group [s: 266 (214, 307) vs. 332 (257, 374), P < 0.05]. However, there was no significant difference in the pre-hospital transfer time and vertical spatial transfer time between the observation group and the control group [pre-hospital transfer time (minutes): 14.50 (12.00, 16.75) vs. 14.00 (11.00, 16.00), vertical spatial transfer time (s): 32.15±17.43 vs. 27.96±18.67, both P > 0.05]. It indicated that mechanical CPR could improve the CPR quality in the process of pre-hospital first aid, and did not affect the transfer of patients by pre-hospital emergency medical personnel. In the evaluation of the in-hospital advanced resuscitation effect, the initial P_ETCO₂ of the patients in the observation group was significantly higher than that of the patients in the control group [mmHg (1 mmHg ≈ 0.133 kPa): 15.00 (13.25, 16.00) vs. 12.00 (11.00, 13.00), P < 0.01], the time of ROSC was significantly shorter than that in the control group (minutes: 11.00±3.25 vs. 16.64±2.54, P < 0.01), and the rate of ROSC was slightly higher than that in the control group (31.58% vs. 23.91%, P > 0.05). It indicated that continuous mechanical compression during pre-hospital transfer helped to ensure continuous high-quality CPR. CONCLUSIONS Mechanical chest compression can improve the quality of continuous CPR during the pre-hospital transfer of patients with OHCA, and improve the initial resuscitation outcome of patients.
Humans ; Cohort Studies ; Carbon Dioxide ; Retrospective Studies ; Hospitals ; Out-of-Hospital Cardiac Arrest ; Cardiopulmonary Resuscitation