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With the goal of enhancing the low sensitivity of the conventional atmospheric pressure chemical ionization (APCI) source due to the ion divergence, here is reported a T-shaped ion source to improve the sensitivity with a portable mass spectrometer for the rapid determination of the pesticides ethoprophos and atrazine in water. Compared with conventional APCI, the ion source improves the sensitivity for the analytes. The results show that the analysis requires less than 2 s, the limit of detection (LOD) is better than 0.1 μ g · mL − 1 , and the relative standard deviation (RSD) is 16% at 1, 5, and 25 μ g · mL − 1 . The recoveries of the analytes are between 80% and 130%, meeting the requirements for rapid pesticide determination in water. [ABSTRACT FROM AUTHOR]

With the increasing prevalence of illicit drugs, social security and human health are at serious risk. However, traditional detection techniques require a lengthy pretreatment process to eliminate matrix interference and do not allow rapid, in situ analysis. Ambient ionization is a powerful tool for the rapid determination of illicit drugs in different matrices because it usually eliminates the need for sample pretreatment, and the portable mass spectrometer brings convenience to in situ detection. This study employed a thermal desorption-electrospray ionization (TD-ESI) source combined with a portable mass spectrometer to rapidly characterize illicit drugs in drinks, instant powders, and solid food surfaces. Air was utilized instead of nitrogen as the carrier gas for TD-ESI/MS in order to save space and cost together with rapid on-site analysis. A full-scan waveform combined with a qualitative pre-scan waveform (QPSW) was employed to form a two-step scanning mode to accurately identify the drugs. The results showed that the limits of detection (LODs) for the analytes were 100–200 ppb in drinks, 700–1000 ppb in instant powders, and 1 ng/cm2 on solid food surfaces. The complete TD-ESI/MS analysis time was less than 1 min. [ABSTRACT FROM AUTHOR]

While portability is a key aspect of small mass spectrometers, they also need to be able to effectively screen the analytes from complex matrices. The accuracy and performance of mass spectrometers depend not only on the identification of parent ion signals in targets but also fragment ion signals. This paper reports on the construction of a device that uses a new time-domain excitation waveform called qualitative pre-scan waveform (QPSW) for its quadrupole ion trap mass spectrometry analyzer. This approach uses scanning to eliminate interfering ions, thus improving the sensitivity for the analyte and removing the cumbersome steps required to convert conventional stored waveform inverse Fourier transform (SWIFT) waveforms from the frequency domain to the time domain. Tests show that the target ions can be fragmented just by introducing air at the moment when the pinch valve is opened without any need for a carrier gas. This simplifies the equipment required, making the mass spectrometer more portable. Tests were undertaken to compare the performance with the use of conventional SWIFT waveforms and to optimize its experimental parameters so that the target ions were effectively accumulated in the ion trap. An approximate 5-fold improvement in sensitivity was achieved by QPSW compared to the SWIFT for 2 μg/mL ketamine. A 5-fold reduction in the limit of detection (LOD) to 20 ng/mL was also obtained for enrofloxacin. In addition, the stability was improved by QPSW with a relative standard deviation less than 13% compared to 16% for SWIFT. [ABSTRACT FROM AUTHOR]

Reducing wear and stabilizing the coefficient of friction (COF) are always frontier issues in the field of automobile braking materials. In this study, the wear resistance of carbon materials and the friction stability of porous materials were combined. Rice husk carbon (RHC) was prepared via vacuum pyrolysis, and the effects and mechanism of RHC contents on the tribological properties of non-asbestos organic braking composite materials (NAOBCM) were studied. The RHC was a porous carbon material mainly containing amorphous carbon and silicon dioxide (SiO2). The COF was improved and stabilized, and the wear resistance was significantly enhanced by adding low-dose RHC. The optimal performance was achieved at 4wt% RHC. As for the mechanism, the porous structure of RHC can prevent stress expansion on the worn subsurface, thus alleviating delamination wear and decreasing the number of large-size abrasive debris. As a result, the abrasive wear is relieved. Finally, the smaller peel-off pits and ploughs reduces roughness and improves the performance. [ABSTRACT FROM AUTHOR]

This study aimed to assess the effects of Apolipoprotein E (APOE) gene polymorphisms, dietary nutrient intake, and their interactions on the prevalence of dyslipidemia in a Yao minority area, China. rs429358, rs7412, rs7259620, and rs405509 of the APOE gene were genotyped in 1014 adults aged ≥30 years by using the MassArray system. Dietary nutrients intake data were ascertained from a 109-item food frequency questionnaire (FFQ). Multifactorial logistics regression analysis showed that dyslipidemia was associated with rs7412-CT/TT genotype (OR: 0.540, Bonferroni correction confidence interval: 0.336–0.869), high fat intake (OR: 1.644, 95% CI: 1.128–2.395), high saturated fatty acid (SFA) intake (OR: 1.668, 95% CI: 1.146–2.428), medium carbohydrate intake (OR: 0.634, 95% CI: 0.461–0.873) and high carbohydrate intake (OR: 0.591, 95% CI: 0.406–0.858). The results of logistics regression multiplication model showed that medium carbohydrate intake in the carriers of the rs7412 minor alleles was associated with a low risk of dyslipidemia (OR: 0.433, Bonferroni correction confidence interval: 0.199–0.941). Genetic variations at the rs7412, dietary fat, SFA, and carbohydrate intake and the interaction between APOE gene polymorphisms and carbohydrate intake are associated with dyslipidemia in Yao nationality people. [ABSTRACT FROM AUTHOR]

We consider price and inventory decisions in a make-to-stock system from the perspectives of a profit-maximizing server and a social planner in which customers are delay-sensitive. Under two information cases (i.e. an almost unobservable case and a fully observable case), customers decide whether to purchase the product based on their utility. The utility is closely related to whether the inventory of the product is available, the product's price, and the waiting time. We first investigate the optimal decision in the almost unobservable case. In this case, the server's inventory strategy depends on the relationship between the unit holding cost of the product and the unit waiting cost of the customer. Additionally, the system utilization factor also affects the inventory strategy. Then, we analyse the corresponding results in the fully observable case. The results illustrate that, in both cases, profit maximization and welfare maximization lead to different pricing and inventory strategies. Finally, the numerical results show that the optimal price is sensitive to delay information, whereas the optimal stock level is not. [ABSTRACT FROM AUTHOR]

Natural environment is an important factor affecting longevity. Soil, water and hair samples from Bama were assayed to investigate the effects of elements on the regional longevity. The concentrations of Cd, Co and Mg in soil and Co in drinking water were significantly higher in longevity area than those in non-longevity area (p < 0.05). The concentrations of K, Mo, Na, Pb and V in soil, Mg, Na, Fe, Li and Mn in drinking water and I, K, Mg, Mn, Na and Sr in hair were significantly lower in longevity area than those in non-longevity area (p < 0.05). Mg, Mn, Na and Sr in hair were affected by soil and drinking water. Our results indicate that adequate concentration of Mg in soil might benefit longevity, excessive concentrations of Na in soil, Mg, Mn and Na in drinking water and Mg, Mn, Na and Sr in hair might reduce lifespan of local residents. [ABSTRACT FROM AUTHOR]

A rare sinulariane-type norcembranoid sinulariadiolide B (1) with a unique cyano group, and a eunicellin-based diterpenoid multifloralin (2), along with two known related analogues, sinulariadiolide (3) and sclerophytin E (4), were isolated from the extract of the South China Sea soft coral Sinularia multiflora. Their structures were elucidated on the basis of detailed spectroscopic analysis and by comparison with previously reported data. Compounds 2 and 4 showed potent antifouling activity against barnacle Balanus albicostatus. [ABSTRACT FROM AUTHOR]

AbstractAdolescents’ bystander defending behavior in cyberbullying contributes to reducing the harm done to cyberbullying victims. This study examined the relationships and underlying mechanisms of parental warmth, friendship quality, empathy and bystander defending behavior in cyberbullying among 848 Chinese adolescents (43.986% girls, mean age = 14.960 years old [SD = 1.398]). The results showed that parental warmth, friendship quality and empathy were all positively correlated with bystander defending behavior in cyberbullying among adolescents. Both friendship quality and empathy played a mediating role between parental warmth and bystander defending behavior in cyberbullying, indicating that parental warmth was associated with increased bystander defending behavior through higher levels of friendship quality and empathy, respectively. Friendship quality and empathy also played a chain mediating role between these two, indicating that parental warmth was linked to increased bystander defending behavior by first associating with higher level of friendship quality and subsequently with greater empathy. These results suggest that high degrees of parental warmth, friendship quality and empathy may all increase the likelihood of bystander defending behavior in cyberbullying among adolescents. This study provides practical implications for improving adolescent bystander defending behavior in cyberbullying. [ABSTRACT FROM AUTHOR]

A new dolabellane diterpenoid, clavirolide H (1), together with eleven known compounds, including two dolabellane diterpenoid (2 and 3), a rare cavernosine-type C17γ-lactone terpenoid (4), a diketopiperazine (5) and seven sterols (6–12), were isolated from the Xisha sponge Fascaplysinopsis reticulata. Their structures were elucidated by extensive spectroscopic analysis, and the four types of compounds of the above isolates were reported from the genus Fascaplysinopsis for the first time. Selected compounds 1, 4–6 and 9–12 were evaluated for cytotoxic activities against K562, HL-60, Hela, HCT-116, A549, L-02 and BEL-7402 cell lines. Compounds 4–6 and 10–12 showed potent cytotoxicitives against HL-60 with IC50 values ranging from 8.8 to 12.4 μM. Compounds 4 and 5 exhibited weak cytotoxic activities against HeLa with IC50 of 20.7 and 27.4 μM, and 5 also has moderate cytotoxicity against HCT-116 with IC50 of 16.3 μM. [ABSTRACT FROM AUTHOR]

Exposure to the heavy metal cadmium has adverse effects on human health, including DNA methylation. This study aimed to investigate the effects of cadmium on liver and kidney functions and Klotho gene methylation and to explore the relationship of methylation level with indicators of liver and kidney functions. Graphite furnace atomic absorption spectrometry was conducted to determine urinary cadmium, and an automatic biochemical analyzer was used to detect indices of liver and kidney functions. PCR pyrosequencing was performed to detect the methylation rate of Klotho. One-way ANOVA was adopted to compare the differences between groups, and the linear correlation to variables was analyzed. Cadmium exposure was negatively correlated with albumin level (r=-0.143, p=0.021) and positively correlated with urinary β2-microglobulin level (r=0.229, p<0.001). However, the methylation levels of Klotho gene was decreased and increased by low and high doses of cadmium exposure, respectively. And Klothomethylation levels were negatively correlated with albumin levels and positively correlated with β2-microglobulin levels.In this study, cadmium exposure affects liver and kidney functions as well as Klotho methylation levels, but the effect on Klotho methylation levels is not linear. Klotho methylation levels also influence liver and kidney functions. [ABSTRACT FROM AUTHOR]

A series of benzothiazole derivatives bearing a 1,3,4-thiadiazole moiety were designed, synthesized and evaluated for their antibacterial, antifungal and antiviral activities. The bioassay results indicated that most of target compounds showed good antiviral activities against tobacco mosaic virus (TMV) and antibacterial activities against Xanthomonas oryzae pv. oryzae (Xoo) and Ralstonia solanacearum (Rs). Especially, the anti-Xoo effect of title compounds 5k (N-(5-methoxybenzo[d]thiazol-2-yl)-2-((5-(2-tolyl)-1,3,4-thiadiazol-2-yl)thio)acetamide) and the anti-Rs effect of title compounds 5a (N-(5-nitrobenzo[d]thiazol-2-yl)-2-((5-(4-(trifluorom ethyl)phenyl)-1,3,4-thiadiazol-2-yl)thio)acetmide) respectively reached 52.4% and 71.6% at 100 µg/mL, which are superior to that of bismerthiazol (32.0% and 52.3%). In addition, the protective and inactivation activities of title compound 5i (N-(5-methoxybenzo [d]thiazol-2-yl)-2-((5-(4-nitrophenyl)-1,3,4-thiadiazol-2-yl)thio)acetamide) against TMV were 79.5% and 88.3%, respectively, which are better than that of ningnanmycin (76.4% and 86.8%). The above research showed that benzothiazole derivatives bearing a 1,3,4-thiadiazole moiety may be used as potential molecular templates in searching for highly-efficient antiviral and antibacterial agents. [ABSTRACT FROM AUTHOR]

Two new steroidal glycosides (named fibrophiopogonins A, B), along with one known glycoside, were isolated from the fibrous roots of Ophiopogon japonicus (Liliaceae). Comprehensive spectroscopic analysis, including 2D NMR spectroscopy, and the results of acid hydrolysis allowed the chemical structure of the compounds to be assigned as 26-[(O-β-D-glucopyranosyl-(1 → 6)-D-glucopyranosyl)]-barogenin- 3-O-[α-L-rhamnopyranosyl-(1→2)]-β-D-glucopyranoside and (25R)-26-[(O- β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl)]- 3β,22α,26- trihydroxyfurost- 5-ene-3-O-[α-L-rhamnopyranosyl-(1→2)]-β-D-glucopyranoside. This is the first isolation of a cholestane glycoside with disaccharide moiety from a Ophiopogon species. The cytotoxic activities of 1~3 against A375 and MCF-7 cells are described. [ABSTRACT FROM AUTHOR]

Purpose: To explore whether soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNARE) complexes are involved in cognitive dysfunction induced by spontaneous recurrent seizures (SRS). Materials and methods: An animal model of epilepsy was established by intraperitoneal injection of kainic acid (KA). Following the onset of SRS, the rats were divided into control group, KA-SRS group, KA+SRS group and KA+SRS+VAP group. Morris water maze and open field test were conducted to evaluate the cognitive function. Protein and mRNA levels of SNAREs complex were measured by Western-blot and RT-PCR, respectively. Besides, the Ca2+ concentration in the hippocampus was also detected. Results: A delayed escape latency and a reduced number of platform crossings were found in the KA+SRS group. Meanwhile, a longer moving distance and time spent in central area were also observed during the open field test. Besides, the Ca2+ concentration in the hippocampus of the KA+SRS group was markedly increased. However, when compared with the KA+SRS group, all indices in the KA+SRS+VAP group were markedly improved. Moreover, the SNARE complexes in the hippocampus of the KA+SRS group were significantly increased when compared with both control group and KA+SRS+VAP group. Conclusions: Results of our study demonstrated that the cognitive dysfunction caused by SRS may be attributed to the modulation expression of SNARE complexes. [ABSTRACT FROM AUTHOR]

The cloud points (CPs) of the copolymers 17R4 and L64 were first measured, and then the effects of salts ((NH4)3C6H5O7, K3C6H5O7) on 17R4 and L64 were researched. After finishing the work described above, the temperature (278.15, 283.15, and 288.15) K of aqueous two-phase systems was determined, which consist of 17R4-(NH4)3C6H5O7, 17R4-K3C6H5O7, L64-(NH4)3C6H5O7, and L64-K3C6H5O7. Finally, the liquid–liquid equilibrium (LLE) data of binodal curve and the tie line for 17R4-(NH4)3C6H5O7aqueous two- phase systems (ATPSs) 17R4-K3C6H5O7ATPSs, L64-(NH4)3C6H5O7ATPSs, and L64-K3C6H5O7ATPSs were obtained. Nonlinear fitting of the empirical equation was used for making the diagram. The results showed that the change in the size of the two-phase areas increases with the increase of temperature. The capacity of the salts to induce phase segregation follows the Hofmeister series, that is, K3C6H5O7 > (NH4)3C6H5O7. In addition, the findings also showed that the phase separation ability of 17R4 is better than that of L64. [ABSTRACT FROM PUBLISHER]

The nexus between energy consumption and economic growth in China is analyzed from the perspective of embodied energy imports and exports in this article. The research results suggest that China is a net embodied energy exporter and it is the inevitable result of China’s present economic development model. Exporting embodied energy contributes significantly to China’s economic development, and the trade-off costs of employment, trade surplus and government tax for China to reduce embodied energy exports are very high. China is bound by its own policies and unable to radically change its embodied energy exporting position within the foreseeable future. [ABSTRACT FROM AUTHOR]

Organic amendments recycle nutrients, but N2O emissions are both environmental and agronomic concerns. We conducted a 4-year field experiment to determine no-till barley (Hordeum vulgareL.) yield and nutrient uptake and soil N2O emissions following a single application of six amendment treatments: (1) no amendment (Check); (2) synthetic N fertilizer (Fert); (3) fresh beef cattle feedlot manure (ManureF); (4) beef cattle feedlot manure compost (CompostR); (5) beef cattle feedlot manure composted with cattle mortalities (CompostM); and (6) separated solids from anaerobically digested cattle feedlot manure (ADM). Barley grown in Year 1 (2006), Year 2 (2007), and Year 4 (2009) (with Year 3 (2008) under fallow) had higher grain yields from ManureF (4.73 Mg ha−1) in Year 2 and ADM (6.30 Mg ha−1) in Year 4 (p< 0.05) than other treatments. The grain N and P contents were not affected (p> 0.05), but N uptake over 3 years (112.8 kg N ha−1yr−1), and P uptake in Year 1 (19.1 kg ha−1yr−1) and Year 2 (14.3 kg ha−1yr−1) from ManureF, were higher (p< 0.05×) than other treatments. The cumulative N2O emissions from ManureF in Year 1 (1.488 kg N ha−1) and from ADM in Year 2 (1.072 kg N ha−1) were higher (p< 0.05) than other treatments while the fraction of applied N emitted as N2O was small (0.00 to 0.79%) and not affected by treatment. However, the percentages of applied N emitted as N2O from compost and ADM were similar to synthetic fertilizer and livestock manure. [ABSTRACT FROM PUBLISHER]

In this study, the aggregation morphology, tensile behavior, and morphology evolution during the tensile test of two isotactic polypropylene (iPP) samples with similar molecular weight and average isotacticity but different uniformities of stereo-defect distribution are investigated by differential scanning calorimetry (DSC), two-dimensional wide angle X-ray diffraction (2D-WAXD), and scanning electronic microscopy (SEM). The results revealed that the uniformity of stereo-defect distribution of iPP determines the crystalline structure and aggregation morphology, and further influences the tensile behavior and morphology evolution during the tensile test. For PP-A with less uniform stereo-defect distribution, its ability of crystallization is stronger compared with PP-B, resulting in smaller spherulite sizes, higher melting point and degree of crystallinity, and narrower distribution of lamellar thickness of the compression molding specimens. During the tensile test, mainly the inter-spherulite deformation takes place at the early stage for deformation, which further results in drastic deformation of lamellar and high degree of reorientation at the strain increases, exhibiting higher yield strength and elastic modulus, and lower elongation at break compared with PP-B; for PP-B with more uniform stereo-defect distribution, larger spherulite sizes, lower melting point and degree of crystallinity in its compression molding sample are observed. During the tensile test, intra-spherulite deformation mainly takes place, which can disperse the tensile stress more uniformly. As the strain increases, lower degree of crystalline destruction and reorientation of the crystallites take place. The yield strength and elastic modulus of PP-B is lower than PP-A, and its elongation at break is higher. [ABSTRACT FROM AUTHOR]

This paper presents a manufacturing process to make an imitative RPC material. The blend was regularly composed of cement, silica fume, and certain content of rubber powder. The granular size distribution of dry blend was optimized to reduce the porosity of set material and the imitative RPC material was characterized by high silica fume content and with very low water to binder ratio. Furthermore, fine crushed aggregate and local natural medium crude sand were used to form mineral skeleton. Properties of various reference concrete series were investigated by conducting multiple tests, including permeability and mechanical strength test, the salt solution absorption test, the accelerated sulphate attack test, etc. The results show that the imitative RPC is an environmental-friendly civil engineering material which owns favorable mechanical strength, high impermeability and qualified excellent durability in sulphate contained environment. [ABSTRACT FROM AUTHOR]

A systematic re-study on gorgonian Muricella sibogae from South China Sea yielded 10 eunicellin-based diterpenoids including two new ones, sibogins C and D (1 and 2). Their structures were elucidated by extensive spectroscopic analyses (1D and 2D NMR, IR and MS) and by comparison with data reported in literatures. All the isolates were tested for cytotoxic and antifouling activities. Compounds 3 and 5 showed significant antifouling activity against the green mussel Perna viridis, and especially 3 was suggested as a potent low-toxic antifouling agent with a large LC50/EC50 value of 18.6. This was the first report on the antifouling activity of the eunicellin-type diterpenoids against the green mussel. [ABSTRACT FROM AUTHOR]

The traditional standardized mortality ratio (SMR) compares the mortality rate of a study population with that of a reference population. In order to measure the performance of a surgeon or a group of surgeons in a hospital performing a particular type of surgical operation, a different SMR is used. This SMR compares the observed number of deaths in a sample with an estimated number of deaths usually calculated based on the average performance of a group of surgeons. The estimated number of deaths involved in the new SMR is not a constant but a random variable. This means that all existing results for the traditional SMR may no longer be valid for the new SMR. In this paper, the asymptotic distribution of the SMR based on an estimated number of deaths is derived. We also use the bootstrap procedure to estimate the finite-sample distribution. A simulation study is used to compare both probabilities of type I error and powers of existing confidence intervals and confidence intervals constructed using the asymptotic and bootstrap distributions of SMR. Our study reveals that, in general, existing confidence intervals are conservative in terms of probability of type I error, and the two new confidence intervals are more accurate. To perform a fair power comparison, the coverage probabilities of existing confidence intervals are recalibrated to match that based on the asymptotic distribution of SMR, and then our study shows that the powers of the asymptotic and bootstrap approaches are lower than existing approaches when the odds ratio of deathQis greater than the odds ratio of death under the null hypothesis,, but higher whenQis smaller than. The effect of patients' risk distribution on the SMR is also investigated. [ABSTRACT FROM PUBLISHER]

The cumulative sum charting procedure is traditionally used in the manufacturing industry for monitoring the quality of products. Recently, it has been extended to monitoring surgical outcomes. Unlike a manufacturing process where the raw material is usually reasonably homogeneous, patients’ risks of surgical failure are usually different. It has been proposed in the literature that the binary outcomes from a surgical procedure be adjusted using the preoperative risk based on a likelihood-ratio scoring method. Such a crude classification of surgical outcome is naive. It is unreasonable to regard a patient who has a full recovery, the same quality outcome as another patient who survived but remained bed-ridden for life. For a patient who survives an operation, there can be many different grades of recovery. Thus, it makes sense to consider a risk-adjusted cumulative sum charting procedure based on more than two outcomes to better monitor surgical performance. In this article, we develop such a chart and study its performance. [ABSTRACT FROM AUTHOR]

Bioassay-guided isolation of the aerial part of Scutellaria barbata yielded three new neo-clerodane diterpenoids scutebatas P–R (1–3), together with two known ones: scutebata E (4) and scutebarbatine B (5). The chemical structures of the isolated compounds were elucidated by spectroscopic methods (NMR and MS) and by comparison with the spectroscopic data reported in the literature. All compounds except 3 showed weak cytotoxicity with IC50 values ranging from 35.11 to 42.73 μM against K562 cell lines, and compounds 1, 2, and 5 also displayed weak activities against HL60 cell lines. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is characterized by high resistance to conventional systemic therapies, rapid progression, easy metastasis and frequent recurrence. There is therefore an urgent requirement to develop novel systemic agents which specifically target hepatoma-associated antigen in the tumors of HCC patients. CD147, a transmembrane glycoprotein, is highly expressed by HCC cells and is strongly associated with HCC progression and prognosis. CD147 in HCC cells modulates HCC growth, promotes invasion and metastasis by stimulating adjacent fibroblasts and HCC cells to produce elevated levels of several extracellular matrix metalloproteinases (MMPs) in the HCC microenvironment. It is also involved in HCC angiogenesis and multidrug resistance (MDR). Clinical progress has been made in HCC treatment using CD147-directed monoclonal antibodies. Here, we give an overview of the literature regarding the molecular features and expression of CD147 in human HCC tissues. We specifically focus on the role of CD147 in HCC invasion and metastasis, as well as in angiogenesis and multidrug resistance. In addition, advances in therapeutic strategies targeting HCC CD147 are summarized. [ABSTRACT FROM AUTHOR]

The research attempts to find out how the location of the CBD(central business district), the distance to the main roads, the distribution of the public facilities, and the urban land-use pattern influence the urban residential land value variations. The study begins by identifying the influences into two categories: general circumstance and micro/neighboring circumstances. Benchmark price and market land value are tested to be the results influenced by general circumstance and both the influential range and the influential force of individual land-use are investigated and compared. At last explicit case comparisons are also taken for testing the result. The finding of the research is not only useful for understanding the spatial patterns of land values, but also beneficial for the policy-makers concerning land administration and urban planning. [ABSTRACT FROM AUTHOR]

Formulas for light propagation in biotissue with cylindrical boundaries are deduced. A model simulating light propagation in one-layered biotissue with a cylindrical boundary is established. Simulation results of the density distribution of absorbed photons are shown when a circularly flat beam is incident on the biotissue. The model can easily be extended to multilayered tissues with cylindrical boundary. [ABSTRACT FROM AUTHOR]