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It is unclear how to develop a model based on the combined satellite data and ground monitoring data to accurately estimate daily NO2 levels. Furthermore, the conventional cross-validation (CV) results represent average levels but the model performance may vary greatly from grid to grid. It is an essential issue to evaluate model's prediction ability in different grids and determine the factors affecting model extrapolating ability, which have never been well examined to date. The aim of this study was to compare the ability of three different methods to estimate the daily NO2 across mainland China during 2014–2016; and to develop a novel two-stage meta-analysis method for exploring the influence of the number and the distribution of nearby sites on grid-level prediction accuracy. For better estimating the daily NO2 level, we developed and compared three methods, including universal kriging model, satellite-based method (Non-linear exposure-lag-response model & Extreme gradient boosting combined technique) and the kriging-calibrated satellite method. For exploring influencing factors, the two-stage meta-analysis method was purposed. The kriging-calibrated satellite method had an overall CV R-square and root mean square error (RMSE) of 0.85 and 7.87μg/m3, better than the Universal Kriging model and the satellite-based method (CV R2 = 0.57 and 0.81). The two-stage meta-analysis method revealed that the model performance did decrease with the sparser distribution of nearby sites. And adding 5 sites within 50 km in the random mode can bring 17.51% improvement in model extrapolating ability. The kriging-calibration can help satellite-based machine learning to provide more accurate NO2 prediction. Our novel evaluation method can provide the suggestion of adding new sites effectively within a limit budget.

Background The clinical staging systems for adenocarcinoma of the esophagogastric junction (AEG) are controversial. We aimed to propose a prognostic nomogram based on real-world data for predicting survival of Siewert type II/III AEG patients after surgery. Methods A total of 396 patients with Siewert type II/III AEG diagnosed and treated at the Center for Gastrointestinal Surgery, the First Affiliated Hospital, Sun Yat-sen University, from June 2009 to June 2017 were enrolled. The original data of 29 variables were exported from the electronic medical records system. The nomogram was established based on multivariate Cox regression coefficients, and its performance was measured using Harrell’s concordance index (C-index), receiver operating characteristic (ROC) curve analysis and calibration curve. Results A nomogram was constructed based on nine variables. The C-index for overall survival (OS) prediction was 0.76 (95% CI, 0.72 to 0.80) in the training cohort, in the validation-1 cohort was 0.79 (95% CI, 0.72 to 0.86), and 0.73 (95% CI, 0.67 to 0.80) in the validation-2 cohort. Time-dependent ROC curves and calibration curves in all three cohorts showed good prognostic predictive accuracy. We further proved the superiority of the nomogram in predictive accuracy for OS to pathological TNM (pTNM) staging system and other independent prognostic factors. Kaplan-Meier survival curves demonstrated the pTNM stage, grade of differentiation, positive lymph node, log odds of positive lymph node and organ invasion were prognostic factors with good discriminative ability. Conclusion The established nomogram demonstrated a more precise prognostic prediction for patients with Siewert type II/III AEG.

Summary HIV latency prevents cure of infection with antiretroviral therapy (ART) alone. One strategy for eliminating latently infected cells involves the induction of viral protein expression via latency-reversing agents (LRAs), allowing killing of host cells by viral cytopathic effects or immune effector mechanisms. Here, we combine a barcoded HIV approach and a humanized mouse model to study the effects of a designed, synthetic protein kinase C modulating LRA on HIV rebound. We show that administration of this compound during ART results in a delay in rebound once ART is stopped. Furthermore, the rebounding virus appears composed of a smaller number of unique barcoded viruses than occurs in control-treated animals, suggesting that some reservoir cells that would have contributed virus to the rebound process are eliminated by LRA administration. These data support the use of barcoded virus to study rebound and suggest that LRAs may be useful in HIV cure efforts., Graphical Abstract, Highlights A genetically barcoded HIV swarm has been constructed and characterized This swarm forms a latent reservoir in antiretroviral (ART)-treated humanized mice Administering an HIV latency-reversing agent (LRA) during ART delays rebound LRA administration during ART also reduces barcode diversity of rebounding virus, Marsden et al. construct a barcoded HIV swarm to study HIV latency formation and rebound in humanized mice. They find that the administration of a PKC modulating HIV latency-reversing agent delays rebound and reduces the genetic diversity of rebounding virus when antiretroviral therapy is stopped, suggesting the reduction of the reservoir.

Dolutegravir (DTG) is a preferred drug for initial treatment of human immunodeficiency virus type 1 infection. We present next-generation sequencing analysis of integrase genotypes during a period of virologic failure in a treatment-naive man who initiated tenofovir disoproxil fumarate/emtricitabine plus DTG.

A finger severed with two or more planes on its vertical axis is called a multi-section severing or multi-plane severing. Replantation of a multi-section severed finger is one of the most serious types. There is more than one anastomotic stoma in the same finger and if an embolism occurred in any one of them, partial necrosis or total necrosis is inevitable, and the risk of a vascular crisis is greatly increased. It is by no means a simple accumulation of single-section replantation, it is uncommon clinically, and it is caused by cutting machines and punch failure. The different position of hand, the shape of the cutting tool, and the speed of the machine will cause different injuries. Multi-section replantation develops based on single-section replantation and it is of the difficulty of hand surgery because of the serious injury, complex conditions, multiple surgical sites, greater difficulty, higher technical requirements, and longer operation time. In most cases, such patients will accept stump revision, which greatly affects the appearance and function. However, in the highly developed microsurgery of today, if the severed tissue is relatively complete, replantation should be considered.

Amputated fingers are not uncommon today because of mechanical accidents, traffic accidents, and other hazards. Replantation is the best method of recovery for amputated fingers. At present, the survival rate of replantation-receiving patients is more than 90%, no matter whether they have an amputation of one finger or all ten fingers, and the postoperative appearance and function are good. To achieve successful replantation does not just depend on the simple replantation and postoperative treatment, and preoperative preparation is also a prerequisite; thus, surgeons should spare enough time to carry out proper preoperative preparations. Routine preoperative preparation includes: (a) Drying and refrigeration are the main methods of storage for amputated fingers, which cannot be soaked in water or disinfectant and can be placed among ice blocks in summer. (b) The wound should be pressurized and bandaged with clean gauze in the case of emergency treatment. (c) Psychological preparation is needed for postoperative recovery. (d) General assessments should be performed by a doctor before the operation to rule out life-threatening risks, determine the indications, and rule out any contraindications. (e) Preoperative preparations for surgical fields and surgical instruments and materials.

Replantation of amputated finger is a detailed and difficult project, requiring surgeons to perform the operation all through the course under the surgical microscope. Besides basic knowledge of orthopedics, vascular surgery, plastic surgery, it is necessary to being proficient in microsurgery technology operation, to achieve stable, accurate, skillful operating skills. According to the general principles, the order of replantation and the specific circumstances, flexible control and temporary adjustment of the surgical plan is needed to ensure that every step of the operation is correct. There are two orders of replantation of amputated fingers. One is antegrade replantation, using by most scholars conventionally, that debridement—skeletal fixation—repair of the flexor and extensor tendon—dorsal vein anastomosis-dorsal skin suture—inherent artery anastomosis—nerve anastomosis-palmar skin suture. The other one is retrograde replantation: debridement-palmar skin suture—finger nerve anastomosis—inherent arteries anastomosis—flexor tendon suture- skeletal fixation—extensor tendon suture—dorsal vein anastomosis-dorsal skin suture. The latter has the advantage of not having to turn over the hands during the surgical procedure, especially for replantation of thumb amputation, and severed fingers in children. Avoiding to pull and sprain the anastomosed blood vessels and nerves when a fracture is fixed. The specific operation are as follows (Fig. 7.1).

Replantation of an amputated finger refers to a surgery on the complete or incomplete amputated finger(s) during which the vessels, nerves, tendons, bones, and skin are re-anastomosed and repaired to make the amputated fingers recover certain functions. It is characterized by a complex surgical process, accurate operation, long duration, and the need for complete immobilization. The requirements for anesthesia are a simple operation, a small impact on the patient’s physiological functions, complete immobilization, painlessness during the operation, easy monitoring, perfect postoperative analgesia, maintenance of dilation of local small vessels, and reduction of vasospasm. This chapter focuses on the common anesthesia modes for replantation of amputated fingers.

Rotation avulsion of fingers is usually caused by a fast rotating machine with a roller and occurs in the left thumb. In most patients, it is characterized by the following: (a) The skin is stripped with the subcutaneous tissue, which is like a flap or avulsion injury. (b) The extensor and flexor tendons are usually pulled out. (c) The digital veins are usually broken near the edge of the skin. (d) The digital nerves are usually pulled out with uneven ends because they are relatively strong. (e) The toughness of the arteries is stronger than that of the veins, but they are weaker than the nerves; thus, they are broken earlier than nerves and later than veins, which is easily understood.

A self-mutilated severed finger is when the patient cuts his own finger off if he or she has an emotional disorder, depression or is intoxicated. It is characterized by the following: (a) Most cases are young men with a bad temper. (b) Most fingers severed in this way comprise the middle and final segments of the left little finger. (c) The wound is smooth with no other injuries, which makes it easy to replant. (d) The patient does not cooperate with treatment for a long time as he or she has so many negative emotions such as regret, angry, and guilt. (e) The replantation is easier compared with other replantations, but postoperative nursing is more difficult because of the patients’ noncompliance.

The replantation of severed fingers of old people relates to those whose over 60 years old. With the development of basic and clinical research, age is no longer a contraindication. If old people suffer severed fingers, their general condition should be assessed first to judge whether they can tolerate surgery, and then consideration should be given to whether or not they wish to undergo replantation and to ensure they understand the function of replanted finger. Any operative treatment should be considered on the assumption of a relatively good condition of the severed finger, short ischemia, good general condition, controlled internal diseases and expected good function recovery. The replantation of severed fingers of old people is always a challenge in clinical practice because of its specificity, but the age range of successful replantation is growing. There was successful case reported for a 72-year-old at No 153 Central Hospital of the People’s Liberation Army in 1990, and for a 74-year-old at No 89 Hospital of the People’ Liberation Army. Another successful case, for a 79-year-old, was described in Hand Surgery, edited by Gu Yudong, Wang Shuhuan and Shi De in 2000.

Severed tissues should be replanted within 6 h at room temperature (20–25 °C), as irreversible necrosis of the muscles occurs because of ischemia. The time can be increased to 12 h if refrigerated (4 °C). The ischemia time for fingers without muscles could be 8 h at room temperature and 12 h under refrigeration. The replantation of a finger whose warm ischemia time is over the time limit is called late replantation. There are very few successful reports of late replantation, and most of these are case reports.

China’s amputated finger replantation technology is in the leading position worldwide in terms of replantation techniques, the number of cases, replantation difficulty, and survival rate after development for nearly 50 years. The success of the replantation of an amputated finger is related to multiple factors such as the patient’s injuries, vascular conditions, and quality of intraoperative vascular anastomosis, and is also closely associated with the postoperative treatment and management. If there is no emphasis on post-replantation treatment and management, the surgery will fail. Special attention should be paid to the vascular crisis (spasm and embolism) that occurs after the replantation of an amputated finger. Treatment and management are of great importance after the replantation of an amputated finger to improve the success rate of replantation.

Finger replantation is an important part of microsurgery, and the key to success is fine blood vessels and nerve anastomosis. Finger blood vessels and nerves are very small; thus, it is very difficult to distinguish them with the naked eye. All surgical protocols must be performed with a microscope, micro-instruments and various special repair materials. The development of the replantation of amputated fingers is closely connected to the development of surgical equipment and materials. It is the continuous development of surgical equipment and materials that promotes the development of replantation of amputated fingers. Below, some of the commonly used equipment and materials for finger replantation are described (Fig. 3.1).

With amputated tissue mass of fingers, some parts’ continuity with the finger body is broken, including bones, joints, tendons, vessels, and nerves, which cannot survive without vascular anastomosis. It is different from general replantation of severed fingers in these respects: (a) The tissues are usually separate from each other. (b) No well-known vessels or nerves to be matched or just pass away. (c) They are difficult to replant and microsurgical techniques are required because the anatomy of the amputated tissues is not clear, but the appearance and functioning will be good if the surgery succeeds.

With the development of industry and agriculture, and diversification of the automatic machine, there are and increasing number of types of severed fingers including those with soft-tissue defects. Soft-tissue defects include defect of the skin, vessels, and nerves, and there is a lack of a regular method for repair because of the complicated conditions, the variety of injuries, and variety of ways to repair them. Professional microsurgical techniques and a knowledge of flaps are required for surgeons so that they choose a suitable flap for repair according to the type of injury and the extent, position, and scope of the defect. Soft-tissue defect was listed as a contraindication for replantation in the 1980s. The replantation used to be applied by shortening bones that would survive, but without satisfactory appearance and function. Sometimes, to preserve the joints and length of the fingers, palliative debridement may cause infection, necrosis of the skin, and poor blood supply, which will affect finger survival or the finger survives, but the functioning is affected by the shortened finger, poor sensation, severe tendon adhesion, and stiff joints. With the development of microsurgery techniques and the maturity of flaps, vessels, tendons, flaps, and composite tissue flaps can be used to repair the soft-tissue defects of severed fingers to reduce postoperative vascular crisis, increase the survival rate, and expand the indications for replantation.

The successful replantation of amputated fingers is based on not only the microsurgery technique, but also the medicines used postoperatively. Three kinds of medicines are generally used after an operation, which are antibiotics, antispasmodics, and anticoagulant drugs. Antibiotics must be used intraoperatively and postoperatively because of complex injuries, the long duration, and prolonged exposure of the wound. The common reasons why the antispasmodic drugs and anticoagulant drugs should be used after an operation are: 1. Blood coagulability is increased after injury and operation, which is the body’s protective physiological response 2. Adrenaline is released after the injury and operation; thus, patients are prone to experiencing vasospasm, an increase in platelets and an increase in blood coagulation, which easily leads to thrombosis 3. Spasticity and thrombosis can be easily induced because of the small diameter, which is commonly 1–3 mm (a minimum of 0.2–0.5 mm), and easy susceptibility to physicochemical factors 4. There is a higher chance of thrombosis because of the small scouring force to anastomotic stoma caused by the small diameter and low blood flow. It is necessary to use antispasmodic drugs and anticoagulant drugs because experiments have proved that the smaller diameter of the vessel, the more likely it is that thrombosis will occur, because the 1-mm vessel has a platelet absorption density twice as high as the 2-mm vessel. In Table 4.1, the commonly used drugs are shown.

The hand is an organ related to labor and beauty that distinguishes humans from other animals. As human civilization progresses, the hands play an irreplaceable role in the process when human activities shift from handicraft to light industry, heavy industry, and electronic technology information. Hands are most susceptible to damage during daily life and work. During industrial production in particular, with relatively low automaticity, it is not uncommon for severe traumas caused by high energy in the hands to result in finger mutilation, leading to life-long disability. Surgeons face the arduous task of attempting to repair and reconstruct the injuries, reduce the patient’s disability and improve their quality of life. Human efforts to carry out studies of hand trauma have never ceased, whether the study be fundamental or clinical. The simple trauma care of hand injuries has been directed to evolve toward the complicated replantation of mutilated fingers and the recovery of hand functions. Long-term clinical practice has demonstrated that patient cooperation and reasonable functional exercise is also of vital significance during the treatment of hand trauma, in addition to the doctor’s accurate judgment, skill proficiency, and proper management. Satisfying results can be achieved in the recovery of hand trauma only after the joint efforts of both doctors and patients.

The final segment of the finger is the furthest structure of the hand, the most frequently used in daily life, and has the highest rate of injury; thus, replantation of the final segment of the finger (fingertip) is common. The functioning of the finger will be seriously affected if the final segment is missing, even though it is small. Compared with the flap method of retaining the length of the finger, replantation is irreplaceable in the recovery of appearance, movement, and feeling. In principle, if the systemic condition of the patients permitted it, if the structure of the severed finger was more or less complete, and if patients and their families required replantation, replantation should be chosen whenever possible.

Severed finger with avulsion is also called a ring avulsed finger that is combined with avulsed arteries and nerves, which are difficult to repair. It usually occurs in workers wearing gloves to operate a high-speed spinning machine or a finger with a ring whose entire soft tissue was avulsed like taking off the gloves, including skin, subcutaneous tissue, vessels, and nerves, just leaving the bones, joints, and tendons. It is characterized by: (a) The destroyed finger has a blunt injury, which is much heavier than the distal part. (b) The avulsed tissues are not in the same plane or even the same tissue. (c) The avulsed vessels and nerves are usually long and may not be able to be used. (d) The finger body of the destroyed finger is usually contused to different degrees.

If the severed part is complete, but the proximal part is seriously damaged or the general condition of the patient does not permit surgery, the severed part could be implanted to another position before being implanted to the in-situ position to recover the appearance and function. This therapy method is called ectopic implantation.

The left hand of a 38-year-old female was injured by an injection molding machine and she was admitted within an hour. Physical examination: The general situation was good, and the vital signs were stable. We found only the thumb and the proximal–distal parts of the ring and little fingers were still residual. The wound was bleeding, irregular with multiple fractures, with tendon, blood vessel, and broken nerve ends exposure. There was no blood supply for the residual fingers, so they were shifted and replanted to metacarpal and radial alignment after satisfactory debridement under anesthesia and fixed with 1.0-mm Kirschner wire. After that, the tendons, blood vessels, and nerves were also anastomosed one by one. The surgery was successful since the replanted fingers were ruddy, with moderate tension and after the tourniquet relaxed. The patient was brought to the ward safely after the operation with the replanted finger fixed with a sterile cotton bandage and padded with broken cotton yarn. Then, the conventional treatment was given to her, and the replanted severed finger successfully survived 2 weeks later. The replanted finger’s function and growth are good after regular follow-up and functional exercise guidance. (Fig. 8.1).

Multiple severed fingers means two or more fingers severed, what is more complicated than would occur in one hand or both hands. Most cases are caused by mechanical damage and the rest are caused by knife cuts or other penetrating trauma. Multiple severed fingers are a common hand injury, compared with a single severed finger, it is characterized by: (a) More serious trauma, a more complicated condition, more blood loss, which would cause changes in blood volume, blood components, and hemodynamics, and activate systemic compensatory vasoconstriction. (b) Longer operating time, more difficulty, which requires not only more energy and stamina from the surgeon, but also a stricter anesthesia way and perioperative period treatment. (c) Higher microtechnical requirements of racing against time to reduce the ischemia time of severed fingers. (d) Close observation of the replanted fingers after the operation and maintaining general stability to prevent high coagulation, while preventing excessive bleeding.

Cholesteric liquid crystal (CLC) with helically aligned molecules, demonstrates unique optical features. Conventionally, such structure reflects a maximum 50% of unpolarised light. Polymer-stabilised CLC was designed to exceed the limit by mixing liquid crystal (LC) and a photopolymerisable monomer of opposite chirality. The reflectance was carefully investigated and the result was 55.7% in the visible region at room temperature, where it exceeded the theoretical limit. Such phenomena were studied and theoretical model was discussed. Electro-optical test showed the driving voltage was of LC cell was slightly changed after polymerisation.

A fiber probe-based positioning scan approach was established, whose precision can reach as high as 0.8 μm. And a set of modified microscope system was designed utilizing this approach, in which the scanning probe microscope (SPM) combined with an optical microscope was manipulated. The optical microscope and scanning probe can conveniently be switched through a switch panel. The observation period of samples can significantly be shortened. And more reliable images can be provided using this approach. Our design can effectively solve the inherent disadvantages of SPM technology, which makes SPM scan and image more reliably, conveniently, safely and rapidly.

The local near-field light scattering and the series dynamic progress of dyestuff PAN particles in solution were investigated taking advantage of optical fiber probe and the near-field detection techniques, including the dissolving and crystallizing progress, Brownian movement and the statistical distribution of particles. Some useful and interesting results were obtained, and are in good agreement with the theoretical analysis. These findings will contribute to the research of near-field optics in a liquid environment as well as provide direct and valuable results for statistical physics.

Summary The fiber micro-probe for near-field scanning optical microscope (NSOM) was fabricated using end-fixed laser-assisted melting and pulling method. The scanning electron microscope (SEM) observation showed that the fiber probes obtained by this method possessed small diameter of tip and large conic angle. The reproducibility came close to 70%. The effects of various fabrication parameters on probes were investigated, including laser power, pulling force, and the diameter of melting zone. The optimal processing conditions were derived based on the experiments and theoretical analysis. This research provides an alternative and advantageous method for fabrication of high-quality fiber probes.