ABSTRACT
Radioactive aerosols harmful to humans are often produced in nuclear accidents, and their source term characteristics (total volume and particle size distribution) and dispersion patterns have important implications for accident response and hazard assessment. However, experimental studies of radioactive aerosols cannot be directly conducted in open space due to the hazardous nature of radioactive aerosols. In this study, silver was used instead of plutonium to study the aerosol source term under different specific internal energy inputs (SIEI) to simulate a low order explosion in an accident. Results show that aerosol release fraction (ARF) and respirable release fraction (RRF) of silver increase linearly with SIEI first, then varies in a range of 8% ~ 19%, with a turning point at SIEI of 1.4 MJ/kg. Analysis suggests an increase of difference between ARF and RRF with respect to SIEI. The size distribution of silver aerosol around 10 µm is influenced by SIEI significantly, which could be possibly attributed to the interactions between silver aerosol and ambient aerosol (solid HE products or rust). Comparison between the source term of silver and plutonium suggests that silver is a good surrogate of plutonium in studying aerosol for SIEI of MJ/kg level.
ABSTRACT
Make-up water used for a district heating system in Beijing is about 63 kg/m(2).a, so the total quantity of make-up water is over 10 million m(3) per year. Water deficiency is very serious in Beijing. Using reclaimed water as make-up water is one of the important measures to relieve water crises of the city. This study is mainly on nanofiltration (NF) process. The reclaimed water for the experiment is the effluent of The Sixth Water Plant, an urban reclaimed water plant in Beijing. Micro-filter (MF) and activated carbon filtration are used as pretreatment units to eliminate turbidity, organic matter in reclaimed water to avoid contamination and scale on the surface of NF membrane. Four SAEHAN NE-90 membrane elements with an array of 2-1-1 are selected for the NF unit and the flow rate is controlled around 1 m(3)/h. Through the test, it has been verified that NF membrane has high removal rate to the salt and impurity of reclaimed water. The average salt removal rate of the system is more than 94%, while the rejections of bivalent ions are more than 98%. The removal rates of organic matter, NH(3)-N and TP are 77%, 96% and 84% respectively. Temperature is a main influence of the process. When temperature is increasing, the permeate flux is increasing as well. The operating pressure is an important factor effecting membrane flux also. By the data comparison it is confirmed that the appropriate operating pressure and the water recovery of NF system are 0.75 MPa and 63.5% respectively.
Subject(s)
Conservation of Natural Resources/methods , Heating , Water , ChinaABSTRACT
Traditional Chinese medicine (TCM) colleges and universities are important positions for inheriting and innovating the TCM culture. Exploring the innovation of teaching modes of ideological and political courses in TCM colleges and universities is a hot topic in current researches on education and teaching reform. There are some problems in the characteristic construction of ideological and political courses in TCM colleges and universities, such as insufficient effective integration of TCM culture, incomplete integrated design, and lack of supervision and evaluation system. In practical exploration, the "11432" teaching mode of ideological and political course based on the cultural characteristics of TCM has been formed. It is guided by "two major goals" and "three requirements", and organically integrates the TCM culture into the teaching of ideological and political course according to the principle of gradual progress. It takes the "Four Adherences" as its practice practical focus, and strives to create a "student-centered" classroom teaching mode. What’s more, it focuses on promoting the organic integration of TCM culture and ideological and political courses from the "five dimensions" in accordance with the fundamental task of "fostering virtue through education" and the requirements for talent training in TCM colleges and universities.
ABSTRACT
Objective:Severe trauma events are emergent, with low incidence and unpredictable. Current guideline does not provide precise recommendations on how the trauma centers should arrange the number of beds in trauma intensive care units while making rational use of medical resources. We analyzed the trauma intensive care unit bed requirement in the branch campus of our hospital to propose a reasonable assessment.Methods:Patients with severe trauma sent to the Intensive Care Unit of Peking University People's Hospital from January 2022 to June 2022 were collected. The daily number of patients received intensive care was counted. The bed requirement of the intensive care unit covering 99% of clinical needs was calculated based on the probability distribution function.Results:From January 2022 to June 2022, 103 patients with severe trauma [74 males and 29 females, aged (51.47±16.06) years, ranging 16 to 87 years] were included in the study. Among the 103 patients, 57 were injured in traffic accidents, 26 fell from a high altitude, 12 fell, 4 were hit by heavy objects, and 4 were stabbed. TISS ranged from 16 to 50. The range of the daily bed requirement in the intensive care unit was 0–10, which was consistent with the Poisson distribution. According to the probability distribution function, nine trauma intensive care beds could meet 99.19% of clinical needs.Conclusions:In severe traumatic events, patients need to be transferred to intensive care unit as soon as possible. For our branch campus, nine trauma intensive care beds can cover more than 99% of clinical needs. It follows that, in accordance with the basic requirements of trauma center construction, hospitals with trauma centers need at least 9 beds in intensive care units. However, traumatic events cannot be predicted; thus, the bed requirement needs to be regularly evaluated.
ABSTRACT
【Objective】 To analyze the composition of urinary calculi in Longnan, Gansu province, and the relationship between the composition and clinical characteristics of patients, so as to provide reference for the prevention and treatment of this disease. 【Methods】 The composition of 500 cases of urinary calculi hospitalized in our department during Apr. 2021 and Feb.2023 were analyzed using the infrared spectrum stone composition analyzer. The clinical characteristics of the patients were evaluated and analyzed. 【Results】 The male-to-female ration of patients was 2.70∶1. Most patients aged 21 to 60 years (437, 87.4%). Most cases were ureteral calculi (72.8%), followed by renal calculi (22.2%), and bladder calculi (5.0%). There were 166 cases of calcium oxalate calculi, 293 cases of calcium oxalate + carbonated apatite calculi, 24 cases of calcium oxalate + carbonated apatite + hydroxyl apatite calculi, 4 cases of calcium oxalate + calcium bicarbonate calculi, 7 cases of urate calculi, 6 cases of carbonated apatite + struvite calculi. Oxalate calculi were the most common in all age groups, and urate calculi were the most common in the 21 to 40 age group. Calcium oxalate calculi were most common in the ureter (127, 76.5%), significantly higher than in other sites (χ2=3.222, P=0.020). Calcium oxalate + calcium hydrogen phosphate calculi was the least common in the bladder, significantly different from the other parts (χ2=2.092, P=0.037). Magnesium ammonium phosphate hexahydrate and/or calcium carbonate or calcium oxalate calculi were the most common in the kidney (50.0%), significantly different from the other parts (χ2=9.448, P=0.007). 【Conclusion】 In Longnan area, the incidence of urinary calculi is significantly higher in male than in female. Ureteral calculi are mainly composed of calcium oxalate + carbonated apatite and calcium oxalate. According to different risk factors, individual prevention programs should be developed.
ABSTRACT
Promoting the collaborative education of curriculum ideology and politics and ideological and political courses is a realistic choice to implement the fundamental task of morality education. The methods, to solve the outstanding problems such as the "uncoordinated" between the two curriculum systems of curriculum ideology and politics and ideological and political courses in medical colleges, the "insignificant" effect of collaborative education between professional course teachers and ideological and political course teachers, and the "insufficient" embodiment of the concept of collaborative education in the medical talent training scheme, are related to the quality of talent training in medical colleges and universities. The collaborative education mode of curriculum ideology and politics based on "great medical sincerity" and ideological and political courses have been formed in the practice and exploration. With "great medical sincerity" as the link, with "two supports" and "four focus points" to build a platform mutually integrated two curriculum; with "three platforms" as the support to improve the collaborative education ability of professional teachers and ideological and political teachers; with "five entry strategy" to promote the implementation of the collaborative education concept. This mode has greatly reversed the "insufficient" phenomenon of collaborative education of curriculum ideology and politics and ideological and political courses in medical colleges.
ABSTRACT
Objective:To understand the status quo of neonatal palliative care attitude of nurses in neonatal intensive care unit (NICU) and analyze the influencing factors, in order to provide reference and direction for hospital management to improve the neonatal palliative care attitude of NICU nurses.Methods:A total of 237 NICU nurses in 9 hospitals in Shijiazhuang, Hebei Province were selected by cluster sampling method from November to December 2021, and the questionnaire was conducted using General Data Survey, Neonatal Palliative Care Attitude Scale (NiPCAS), the Jefferson Scale of Empathy (JSE) and Coping with Death Scale (CDS). And analyze the results.Results:The total score of the NICU nurses′ neonatal palliative care attitude was 89.35 ± 18.86. The average score of each dimension from high to low was belief, work experience, resources, organization, and obstacle; and the total score of neonatal palliative care attitude was positively correlated with empathy ability ( r=0.653, P<0.01) and death coping ability ( r=0.597, P<0.01), in addition the factor of barrier was negatively correlated with empathy and death coping ability ( r=-0.602, -0.526, both P<0.01) Multiple linear regression analysis showed that educational background, whether nursing dying infants, frequency of attending hospice nursing education in hospitals, empathy ability and death coping ability were the influencing factors of neonatal palliative care attitude, which could explain 47.3% of the total variation. Conclusions:NICU nurses′ neonatal palliative care attitude was generally at a moderate level, and affected by five factors such as education. It is suggested that hospital management should provide to improve empathy ability and death response ability as the premise of personalized, diversified education training support, multiple ways, multi-level improve its empathy ability and death coping ability, improve neonatal palliative care attitude, and then improve the quality of nursing service.
ABSTRACT
Objective:To investigate the status quo and influencing factors of spiritual care needs among elderly stroke inpatients, in order to provide reference for formulating targeted interventions.Methods:A total of 417 elderly stroke inpatients were selected in five Third-A hospitals from August 2021 to January 2022 by convenient sampling. The questionnaire was conducted using the General Data questionnaire, the Nurse Spiritual Therapeutics Scale (NSTS), the Stigma Scale for Chronic Illness (SSCI) and the Perceived Social Support Scale (PSSS). Multiple linear regression was used to analyze the influencing factors of spiritual care needs of elderly stroke inpatients.Results:The total score of NSTS among 417 elderly stroke inpatients was 31.98 ± 4.39. The dimension of highest and lowest average score were "create good atmosphere" (3.23 ± 0.58) and "help religion" (2.01 ± 0.62), respectively; the results of regression analysis showed that religious belief, education background, course, stigma, and social support were the main factors influencing spiritual care needs among elderly stroke inpatients ( t values were -6.54-7.11, P<0.05). Conclusions:The spiritual care needs among elderly stroke inpatients were moderate. It is suggested that nurses should strengthen their own spiritual care knowledge and ability, and take targeted spiritual care measures according to the individual characteristics and differences of patients, reduce their stigma, improve the social support, to meet their spiritual care needs to the greatest extent.
ABSTRACT
In recent years, cancer had become one of the main causes of death in children and adolescents, which had great adverse effects on their physiology and psychology, leading to serious physiological and psychological problems. Adventure based counseling had the effect of improving physical and mental health and quality of life, and had been widely used in the nursing of children with cancer. This paper reviewed the concept, intervention methods, applicable population and its application in the nursing of children and adolescents with cancer, in order to provide reference for the further research and application of adventure based counseling in children and adolescents with cancer in China.
ABSTRACT
Objective:To evaluate the efficacy and safety of apatinib in combination with chemoradiotherapy for head and neck squamous cell carcinoma (HNSCC).Methods:37 patients orally received apatinib at 250 mg/d during concurrent chemoradiotherapy until completion of radiotherapy, complete remission assessed by imaging examination, the onset of unacceptable toxicity or death. Baseline characteristics, objective response rates (ORR) and adverse events were assessed in all enrolled patients with complete baseline and safety data. Progression-free survival (PFS) and overall survival (OS) were calculated by Kaplan-Meier method. Prognostic factors were statistically identified using Cox regression models.Results:The ORR was 85%(95% CI: 72%-98%). The median PFS was 17.9 months and the 2-year OS rate was 62%(95% CI: 48%-80%). Ineffective short-term efficacy ( HR=0.035, 995% CI: 0.02-0.652, P=0.025) was an independent risk factor for poor OS. In addition, ineffective short-term efficacy ( HR=0.104, 95% CI: 0.017-0.633, P=0.014) and lymphocytopenia ( HR=17.539, 95% CI: 2.040-150.779, P=0.009) were independent risk factors for poor PFS. Common adverse events (>60%) included lymphocytopenia (76%), leukopenia (68%) and irradiation-induced mucosal injury (65%). The most common treatment-associated grade 3 adverse event was lymphopenia (49%). Conclusions:Apatinib combined with chemoradiotherapy yield significant anti-tumor activity for HNSCC with controllable toxicity. For patients with advanced HNSCC, short-term efficacy and lymphocytopenia may be potential predictors for clinical efficacy of apatinib combined with chemoradiotherapy.
ABSTRACT
Objective:To investigate the ability of doctors in different regions and levels of hospitals in assessing the severity of severe trauma in China.Methods:A total of 38 trauma centers of China Trauma Rescue & Treatment Association (19 tertiary hospitals and 19 secondary hospitals, including 20 eastern and 18 western hospitals) were selected from November 2018 to May 2020. Two junior, two middle, and two senior emergency surgeons were selected in each center. Injury severity score (ISS) was performed on 10 patients with severe trauma, and the qualified rate was analyzed.Results:The qualified rates of junior, middle, and senior doctors were 56.05%, 56.18%, and 56.71%, respectively ( P>0.05). The qualified rates of tertiary and secondary hospitals were 63.07% and 49.56%, respectively ( P<0.01). The qualified rates of eastern and western hospitals were 67.00% and 44.44%, respectively ( P<0.01). Conclusions:The overall level of injury assessment of severe trauma patients by doctors in China is satisfactory, while there are still differences in hospital levels and regions. In the future, attention should be paid to the training and system construction in primary hospitals. We should actively support the construction and development of hospitals in the western regions and realize the standardization of trauma treatment in China as soon as possible.
ABSTRACT
With the appearance of the disadvantages of traditional tumor treatment, immunotherapy has entered people′s horizons as modern emerging treatment strategies, among which plant polysaccharides have received much more attention due to their antitumor activity and significant immunomodulatory effects. Tumor-associated macrophages (TAMs), as a component of tumor microenvironment, are important factors affecting tumors, and the regulation of TAMs by plant polysaccharides is one of the effective immunotherapy to treat tumor. In this review, we mainly described the regulation of TAMs by plant polysaccharides and the underlying mechanisms, and then gave an outlook on the research interests and the development of plant polysaccharides as immune adjuvants, aiming to provide reference for the study of plant polysaccharides in the immunotherapy for tumors.
ABSTRACT
Due to water shortage, municipal reclaimed water rather than surface water was replenished into recycling cooling water system in power plants in some cities in China. In order to understand the effects of the measure on carbon steel corrosion, characteristics of two kinds of foulant produced in different systems were studied in the paper. Differences between municipal reclaimed water and surface water were analyzed firstly. Then, the weight and the morphology of two kinds of foulant were compared. Moreover, other characteristics including the total number of bacteria, sulfate reducing bacteria, iron bacteria, extracellular polymeric substance (EPS), protein (PN), and polysaccharide (PS) in foulant were analyzed. Based on results, it could be concluded that microbial and corrosive risk would be increased when the system replenished by municipal reclaimed water instead of surface water.
ABSTRACT
Objective To evaluate the intraoperative condition and prognosis of extracorporeal memberane oxygenation (ECMO) in patients with idiopathic pulmonary fibrosis (IPF) undergoing single lung transplantation.Methods Fifty-five patients (49 males and 6 females,aged 18-75 years,ASA physical status Ⅲ or Ⅳ) undergoing single lung transplantation were divided into ECMO group (E group,n =41) and control group (C group,n =15).Lung ischemia time,operative time,intraoperative crystal fluid volume,intraoperative colloids fluid volume,total fluid volume,albumin volume,bleeding volume,blood transfusion volume and urine volume were recorded.ECMO time,extubation time,the length of ICU stay and postoperative hospital stay were assessed.Results There was no significant difference in lung ischemia time,operative time,intraoperative crystal fluid volume,intraoperative colloids fluid volume,total fluid volume,albumin volume,bleeding volume,volume of blood transfusion,urine volume,ECMO time,extubation time,the length of ICU stay,postoperative hospital stay and mortality rate during hospitalization between the two groups.Blood plasma volume was significantly more in E group (9.3 ± 4.5 mL/kg) than that in C group (5.4 ± 4.2 mL/kg;P＜0.01).ECMO time was positively related to extubation time,the length of ICU stay and mortality rate during hospitalization (P＜0.01).Conclusion ECMO does not affect intraoperative condition and prognosis of patients.According to ECMO time we can judge the prognosis of patients.
ABSTRACT
Objective To study the influence of the convergence angle and cement space on the fit of CAD/CAM all-ceramic crowns.Methods The PMMA resin was produced in two groups,group A (2 degrees) and group B (4 degrees),30 in each group,and each group was divided into 3 sub-groups A 1,A2,A3;or B 1,B2,B3.Each subgroup included 10 patients with a CAD/CAM all-ceramic crown with PMMA resin generation type,but the cement space was 40 μm,60 μm,or 80 μm.The internal clearance edge of the double color silicone rubber impression reproduction technology of the all-ceramic crown was observed under the microscope.Analysis Micro-image software was used to measure the edge gap,and the resulting data were analyzed using SPSS 20.0 software.Results When the cement space is the same,the difference between 2 degrees and 4 degrees was statistically significant.Conclusion The fit is the best when the cement space is 60 μm and the convergence angle space is 4 degrees.
ABSTRACT
wearable microfluidics have wide applications in medical, sports and military field. with the help of wearable microfluidics, through the direct physical contact between the chip and skin, the pH, glucose, lactate, sodium/potassium, calcium and heavy metal in the body fluid can be detected from sweat, tear and saliva without puncture for blood. And these information are of great importance for the monitoring of vital signs and disease diagnosis. This paper introduced the most recent development and applications of the wearable microfluidics in the body fluid testing and drug delivery. The up-to-date research development for the drug delivery using wearable microfluidics was also briefly introduced in this article. The forecast of the emerging trend for wearable microfluidics and discussion of potential technique barriers was also provided at the end of this article.
ABSTRACT
Objective To investigate the value of S-Detect classification in differential diagnosis of breast mass . Methods The data of forty-seven patients with breast mass lesions ( n=61) from our hospital during January to December in 2016 were retrospectively analyzed . Both the man-made BI-RADS classification ( identified by three different specialist physicians with 2 ,5 and 7 years of experience , respectively) and computer S-Detect classification were performed . The sensitivity ,specificity ,accuracy , positive predictive value and negative predictive value of the man-made BI-RADS classification and S-Detect classification of the benign or malignant diagnosis of breast lumps were calculated . The ROC curve was further plotted ,and the area under the curve ( AUC) of each group was compared ,respectively . Results Sixty-one breast mass lesions were confirmed 36 benign lesions and 25 malignant lesions by pathological biopsy . The sensitivity ,specificity and accuracy of man-made BI-RADS classification were as follows:2-year experience physicians 69 .4％ ,72 .0％ and 70 .5％ ;5-year experience physicians:64 .0％ ,92 .0％ and 75 .4％ ;7-year experience physicians:69 .4％ , 92 .0％ and 78 .7％ . The diagnostic sensitivity , specificity , and accuracy of S-Detect classification were 80 .6％ ,96 .0％ and 86 .9％ . The specificity ,accuracy and positive predictive value of S-Detect classification were significantly higher than those of 2-year experience physicians by BI-RADS classification ( P <0 .05) . The area under the ROC curve of each group was 0 .729 ,0 .786 and 0 .801 for 2 , 5 and 7-year experience physicians , respectively , and 0 .917 for S-Detect classification . Conclusions Compared with the man-made BI-RADS classification ,S-Detect classification has advantages in diagnosis of the benign or malignant of breast mass and is helpful to improve the accuracy of diagnosis , especially for junior physicians .
ABSTRACT
Objective To observe the blood flow changes of left ventricular cavity and quantify the energy loss (EL) and circulation of left ventricular during systole and diastole in patients with dilated cardiomyopathy(DCM) via vector flow mapping(VFM).Methods Thirty-six healthy volunteers and 32DCM patients were enrolled.According to the severity of mitral regurgitation(MR),DCM patients were divided into two groups.The quantitative parameters,including average energy loss(EL-base,EL mid,EL-apex) and circulation (vortex quantity,vortex area,circulation) were measured in the different periods of VFM imaging mode in apical four-chamber view,apical three-chamber view and apical two-chamber view respectively.The difference of parameters was evaluated between different groups during the different periods.The early transmitral valve blood flow velocity E,the late transmitral valve blood flow velocity A,the ratio of early transmitral valve blood flow velocity to the early diastolic mitral valve velocity E/e,the ratio of early transmitral valve blood flow velocity to the late transmitral valve blood flow velocity E/A and Tei index were derived via dual-Doppler imaging technology.Meanwhile,the correlation between VFM parameters with E,A,E/A,E/e or Tei index was also analyzed.Results ①The level of EL were decreased significantly among EL-mid and EL-apex during early diastole,EL-mid during mid-systole,EL-mid and EL-apex during late-systole (P ＜0.05),when compared with the control group.The vortex quantity,vortex area and circulation during early diastole and the vortex area and circulation during atrial contraction period were significantly different between two groups (all P ＜ 0.05).As for mid-diastole,only vortex area showed significant difference (P ＜0).01).(②) When compared with different grades of MR in DCM patients,the level of all segments EL during diastole and EL-base during systole increased with severity of MR(P ＜0.05).The circulation during diastole also increased with the severity of MR(P ＜0.05).③The vortex area and circulation had positive correlation with E/e during diastole in all subjects(all P ＜0.05).The vortex area during atrial contraction period and early diastole had positive correlation with E/A and Tei index in all subjects(r =0.630,0.345,0.468,0.316,0.663,0.264,respectively,allP ＜0.01).EL-mid during late-systole were negatively correlated with LV end diastolic volume,end systolic volume,but positively correlated with ejection fraction in all subjects(r =0.335,-0.312,0.340,respectively,all P ＜0.05).While,there was positive correlation between E/A with the basal segment of mid-diastole(r =0.376,P ＜0.01).Conclusions The visualization of hydromechanics inside the heart of DCM patients could be directly accomplished by VFM,which can provide a new method for diagnosis and evaluation of DCM.
ABSTRACT
Objective To explore the relationship between atherosclerotic plaque stability and junctional adhesion molecule A (JAM-A) in atherosclerotic mice.Methods Twenty-six apolipoprotein E gene knockout(ApoE-/-) mice were divided into three groups.Group A (six mice) was control group,group B (ten mice) was disposed by ligation and high-fat diet and group C was disposed by high-fat diet with ten mice.The formation process of plaques were observed with high resolution ultrasound(22 MHz),and plaque markers were detected to evaluate palque stability for secondary grouping (group D was vulnerable plaque group and group E was stable plaque group).The plaque stability were evaluated by plaque vulnerability index and the expression of JAM-A were analyzed using immunohistochemical staining.The relationship between atherosclerotic plaque stability and JAM-A in atherosclerotic mice were estimated with statistical methods at last.Results There was no plaque in carotid artery of group A.On the contrary,obvious plaques were observed in carotid artery of group B and C.The total serum lipids level in group A was normal.But high-fat diet could obviously decrease the serum HDL-cholesterol level of group B and group C when compared with the controls(P ＜0.05).High-fat diet could increase the ratio of non-HDL-cholesterol (TC,TG,LDL).As shown with pathological staining,the content of extracellular lipids and foam cells in the plaque were significantly increased vs.control (P ＜ 0.05).On the contrary,the content of smooth muscle cells and collagen fibers were significantly increased vs.control(P ＜0.05).The plaque vulnerability index of group D was higher than that in group E(P ＜0.01).The expression of JAMA was increased in group D and E,and in group D was higher(P ＜0.01).While,few JAM-A expression in group A.There was significant correlation between plaque vulnerability index and JAM-A (P＜0.01).Conclusions High resolution uhrasound(22 MHz) can observe the formation of carotid plaque in ApoE-/-mice.There was a positive correlation between JAM-A expression and the vulnerability of plaque in carotid artery.JAM-A might be used for evaluation of plaque stability as a new indicator.
ABSTRACT
Digital polymerase chain reaction ( PCR) has been experiencing a rapid development during the past few years. Comparing with the traditional real-time quantitative PCR ( RT-qPCR) , using the same primer and probe, the accuracy for the absolute quantification of target gene is significantly improved. The development of digital PCR is directly related to the development of microfluidics. The integrated fluid circuit is an early combination of the microfluidics and digital PCR, which has a complicated fabrication process with high cost. Recently, researchers are trying to apply the droplet microfluidics in digital PCR, and the droplet microfluidic chip is able to generate millions of droplets within a short time. Each of these droplets containing no more than one target gene is a reaction chamber during the amplification process. After amplification, each droplet is tested to achieve the absolute quantification of the target gene. This paper reviews the recent progresses of droplet digital PCR, and the applications of droplet digital PCR in biological, medical and environmental fields.