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In wireless communication systems, the performance of the receiver is very sensitive to time and frequency offsets. In particular, orthogonal frequency division multiplexing (OFDM) systems are highly vulnerable to those offsets due to inter-carrier interference (ICI) and inter-symbol interference (ISI). To solve this problem, wireless local area network (WLAN) systems transmit a preamble for synchronization. In this paper, we propose a joint time and frequency offsets estimation technique based on convolutional neural network (CNN) for WLAN systems. In the proposed technique, the correlation between the received signal and the transmitted preamble is performed first. Then the frequency offset is coarsely compensated by several hypothesized offsets. The compensated signals are inputted to the proposed CNN and the CNN predicts the time and frequency offsets. The estimation performance is examined through computer simulation. According to the results, the proposed time offset estimator shows 3 dB to 6 dB performance gain, and the frequency offset estimator shows much lower root mean square error (RMSE) performance than the conventional technique at low SNRs

Background The aims of this study were to (1) describe our functional stepwise multiple needle puncturing (MNP) technique as the final step in medial ligament balancing during total knee arthroplasty (TKA) and (2) evaluate whether this technique can provide sufficient medial release with safety. Methods A total of 137 patients with 212 consecutive knees who underwent TKAs with or without functional stepwise MNP of superficial medial collateral ligament was recruited in this prospective cohort. Eighty-one patients with 129 knees who performed serial stress radiographs were enrolled in the final assessment. Superficial medial collateral ligament was punctured selectively (anteriorly or posteriorly or both) and sequentially depending on the site and degree of tightness. Mediolateral stability was assessed using serial stress radiographs and comparison was performed between the MNP and the non-MNP groups at postoperative 6 months and 1 year. Clinical outcomes were also evaluated between 2 groups. Results Fifty-five TKAs required additional stepwise MNP (anterior needling 19, posterior needling 3, both anterior and posterior needling 33). Preoperative hip-knee-ankle angle and the difference in varus-valgus stress angle showed significant difference between the MNP and the non-MNP groups, respectively (P = .009, P = .037). However, there was no significant difference when comparing the varus-valgus stress angle between the MNP and the non-MNP groups during serial assessment. Clinical outcomes including range of motion also showed no significant differences between the 2 groups. Conclusion Functional medial ligament balancing with stepwise MNP can provide sufficient medial release with safety in TKA with varus aligned knee without clinical deterioration or complication such as instability. Level of Evidence Level II, Prospective cohort study.

Background This study aimed at assessing the morphometry of resected femurs in Korean patients during total knee arthroplasty (TKA) and comparing these measurements with current Western-designed femoral component dimensions. Methods This single-blind, prospective, randomized, controlled trial involved intraoperative measurements for 271 femoral component implantations from 3 contemporary TKA systems, with 2 systems offering narrow sizing options. The difference between femoral component dimensions and the resected surface of distal femur was measured in millimeters at 5 distinct zones. Results Overhang of standard femoral component was common in the anterior-medial condyle and anterior-lateral condyle ranging from 50.8% to 99.0% and 21.5% to 88.0%, respectively. With narrow femoral components, the rate of overhang reduced to 21.5%-30.2% and 9.2%-32.1%. Conversely, underhang rates were higher over the anterior flange width, middle medial-lateral and posterior medial-lateral zones. Standard components displayed higher underhang rates at these zones compared to narrow components. The good fit rate for femoral component was low among the 3 systems ranging from 1.0% to 56.0%. System with narrow option sizing increases the underhang rates in males, while improving the component fit among females at similar zones with rate ranging from 5.2% to 52.9%. Conclusion Currently available TKA implant designs may not provide a perfect match for the distal femoral shape of the Korean population. The availability of implants with standard and narrow options can substantially improve the optimal fitting of femoral components in the Korean population.

Purpose The purpose of this study was to evaluate the disparity between the preoperative target correction amount and the postoperative correction amount in open wedge high tibial osteotomy (OWHTO) in patients divided according to the planned osteotomy gap. Materials and methods Seventy-two patients were divided into two groups (group 1 with the planned opening gap lager than the mean opening gap length of total patients and group 2 with a smaller opening gap). The opening gap was determined according to the target weight bearing line (WBL) ratio on the preoperative whole leg radiograph. Absolute and relative values of the disparity between the target and postoperative WBL ratios were compared between groups in order to clarify whether the disparity was deviated toward over- or under-correction. Results The absolute value of disparity between the target and postoperative WBL ratios in group 1 was significantly larger than that in group 2 (6.01%±5.68% vs. 3.32%±3.38%; p=0.02). However, there was no statistically significant difference in relative values between groups (p=0.54). Conclusions The postoperative WBL ratio after OWHTO was different from the preoperative target WBL ratio if the planned osteotomy gap was large. This mismatch was not deviated toward one side, either over- or under-correction.

Background Anatomic tunnel formation and remnant preservation are valuable aspects of anterior cruciate ligament (ACL) reconstruction. However, anatomic landmarks are difficult to observe during remnant-preserving ACL reconstruction (ACLR). The aims of this study were to evaluate the: 1) femoral tunnel location created with guidance from the apex of the deep cartilage margin (ADC) and footprint compared to anatomical reference; and 2) relationship between femoral tunnel location and outcomes of ACLR. Methods A total of 109 ACLR patients without revision ACLR, multi-ligament reconstruction, peri-knee fracture, and osteotomy were included. The femoral tunnel was formed at the most proximal corner of the femoral footprint using a posterior trans-septal portal as the viewing portal. The distance from the tunnel center to ADC was measured by computed tomography and arthroscopy. The two measurements were then compared. Finally, femoral tunnel location was compared to the anatomic reference and correlated with the outcomes. Results The average distance from ADC to the femoral tunnel center was 7.0 ± 1.4 mm as measured by arthroscopy, and 7.2 ± 2.0 mm using three-dimensional computed tomography. There was no statistically significant difference between the two methods (P = 0.420). Clinical and stability outcomes were significantly improved postoperatively. Clinical outcome was not related to femoral tunnel location; however, stability outcome was related to femoral tunnel location: the more proximally located femoral tunnels showed better stability. Conclusion The ADC can be a possible landmark in remnant-preserving ACLR using a trans-septal portal. A more proximal femoral tunnel, which is located at the proximal corner of the ACL remnant, can provide stability advantage during remnant-preserving ACLR.

The purpose of this study was to find the most suitable and safe position of the transseptal portal in anatomic anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) reconstructions. The hypothesis of this study was that area and position of the transseptal portal are different between ACL and PCL reconstructions for the observation of native footprint. A matched-pair comparison study was conducted on the arthroscopic images of 100 consecutive patients who underwent ACL reconstruction and 50 consecutive patients who underwent PCL reconstruction. The transseptum was divided into six compartments. The opened compartments for each surgery were then evaluated to find which anatomical structures are well seen. The anterior middle and upper parts were necessary for the ACL reconstruction, whereas middle and lower portions of the anterior and posterior compartments were necessary for the PCL reconstruction. A larger opening was necessary for PCL reconstruction than that for ACL reconstruction. The ACL posterior one-third, ACL femoral attachment, and apex of the deep cartilage margin (DCM) were viewed in 100% of the patients during ACL reconstruction. The PCL posterior one-third, PCL tibial attachment, PCL fovea margin, and medial meniscus around posterior margin were always viewed during PCL reconstruction. The anterior part of the septum, from the middle to the upper portions of the transseptum, was necessary to be opened for visualization of the femoral footprint and DCM of the lateral femoral condyle during ACL reconstruction. The anterior and posterior parts of the septum, from the middle to the lower portions of the transseptum, were necessary for excellent visualization of the PCL tibial footprint during PCL reconstruction. These paths of the transseptal portal for each surgery will help surgeons obtain both anatomic footprint restoration and maximal remnant preservation through the most suitable and safe means. This is a case–control study; level of evidence is 3.

Background Adoptive transfer of immune cells such as T cells and natural killer (NK) cells has emerged as a targeted method of controlling the immune system against cancer. Despite their significant therapeutic potential, efficient methods to generate adequate numbers of NK cells are lacking and ex vivo-expansion and activation of NK cells is currently under intensive investigation. The primary purpose of this study was to develop an effective method for expansion and activation of the effector cells with high proportion of NK cells and increasing cytotoxicity against liver cancer in a short time period. Methods Expanded NK cell-enriched lymphocytes (NKL) designated as “MYJ1633” were prepared by using autologous human plasma, cytokines (IL-2, IL-12 and IL-18) and agonistic antibodies (CD16, CD56 and NKp46) without an NK cell-sorting step. The characteristics of NKL were compared to those of freshly isolated PBMCs. In addition, the cytotoxic effect of the NKL on liver cancer cell was examined in vitro and in vivo. Results The total cell number after ex vivo-expansion increased about 140-fold compared to that of freshly isolated PBMC within 2 weeks. Approximately 78% of the expanded and activated NKL using the house-developed protocol was NK cell and NKT cells even without a NK cell-sorting step. In addition, the expanded and activated NKL demonstrated potent cytotoxicity against liver cancer in vitro and in vivo. Conclusion The house-developed method can be a new and effective strategy to prepare clinically applicable NKL for autologous NK cell-based anti-tumor immunotherapy. Electronic supplementary material The online version of this article (10.1186/s12885-019-6034-1) contains supplementary material, which is available to authorized users.

Background: Vaccination for hepatitis B virus (HBV) after chemotherapy among pediatric patients with acute leukemia is still a debated issue. We investigated HBV immunity before and after chemotherapy and assessed immune response to re-vaccination after chemotherapy. Methods: We retrospectively analyzed data of children and adolescents aged

Background We report a case of hardware failure after distal femoral osteotomy (DFO) with a broken screw pulled out from the locking hole and positioned within the knee joint. Case presentation A 57-year-old man presented to our orthopedic outpatient department with 3-months history of an unusual painful swelling at the operated area following DFO. The leakage of joint fluid from the penetrated suprapatellar pouch was assumed to be the reason for this complication. Conclusions The overall aim of this case report is to provide a lesson to budding surgeons who might experience a similar situation that cannot be easily explained, like the unexpected complication in the present case.

Purpose The purposes of this study were to analyze and compare 1) the postoperative fixation configurations, and 2) radiological and clinical outcomes between the new conceptual fixation device (LCfit) and the conventional locking plates. Methods Retrospective comparative analysis of 304 cases who underwent open-wedge high tibial osteotomy with four different locking plate systems including the LCfit system was conducted. In analyzing the fixation configuration of each locking plate system, the plate position, the gap between plate and bone, screw angle, and screw length were evaluated from postoperative CT scans. The clinical outcomes and radiological parameters of four patient groups corresponding to the four locking plate systems were also compared. Results In the analysis of the fixation configurations, the LCfit system showed more posteromedial plate position, decreased gap between plate and bone, reduced screw angle, and longer screw length compared to the other three locking plates. However, there were no significant differences in clinical outcomes and radiological parameters such as hip-knee-ankle angle, weight-bearing line position, medial proximal tibial angle, and posterior slope between the four groups. Conclusion The newly designed fixation system (LCfit) for open-wedge high tibial osteotomy showed fixation configurations that have theoretical mechanical advantages over conventional anatomical locking plates. However, there were no significant differences in clinical outcomes and radiological parameters between LCfit and the other locking plate systems. Level of evidence Level III, retrospective cohort study.

This study was conducted to evaluate the effect of the aging period prior to freezing on the meat quality of Hanwoo longissimus dorsi (LD) muscle. Three different combinations of aging and freezing periods (0/90, 20/70, and 40/50) were examined LD muscle at 24 h postmortem under an identical storage time of 90 d. The pH and lightness slightly increased with increasing aging period. However, there were no significant (p>0.05) differences in redness and yellowness. The solitary freezing treatment (0/90) had the significantly (p 0.05) difference in shear force and sensorial properties between 20 and 40 d aging prior to freezing. Therefore, 20 d aging prior to freezing may be a sufficiently effective strategy to improve the tenderness and sensorial properties of Hanwoo LD muscle

The aim of this study was to compare the physicochemical changes of hot-boned chicken breast and leg muscles. Chicken breast and leg muscles from 56 broilers were excised within a 15 min post-mortem (PM) and stored at 20 C. Physicochemical traits were determined at 0.5, 6, 12, and 24 h PM. The ultimate pH of leg muscle was higher than that of breast muscle (p

The objective of this study was to examine the effect of hot-boning and soy sauce as a curing agent on the processing properties of beef jerky. Beef jerky was prepared under the following four treatment conditions; Beef jerky with cold-boned beef and salt solution, beef jerky with cold-boned beef and soy sauce solution, beef jerky with hot-boned beef and salt solution, and beef jerky with hot-boned beef and soy sauce solution. Cured meat and jerky containing hot-boned beef had a significantly higher pH, water holding capacity (WHC), moisture content, Myofibrillar fragmentation index (MFI), processing yields, tenderness, and sensorial scores than samples containing cold-boned beef (p

This retrospective study was performed to determine the seroprevalence of hepatitis A virus (HAV) in children and adolescents with hematologic malignancies after the completion of chemotherapy and hematopoietic cell transplantation (HCT). Of 97 enrolled patients, 60 (61.9%) were seropositive for HAV. The seroprevalences in patients undergoing chemotherapy and HCT were 60.3% (41/68) and 65.5% (19/29), respectively (P = 0.628). No significant factors associated with seropositivity for HAV after chemotherapy and HCT were identified. Anti-HAV tests and HAV re-vaccinations can be considered in children and adolescents with underlying hematologic malignancies after chemotherapy and HCT based on the anti-HAV results.

The purpose of this study was to investigate the quality characteristics of pork jerky prepared under two curing methods (immersion and tumbling). Jerky was dried using cured pork meat immersed for 6, 12, 24, or 48 h, or tumbled for 10, 20, 30, or 60 min. In jerky manufacturing, the tumbling process had a significant influence on increased moisture contents, reduced textural hardness, and improved in sensorial tenderness, juiciness, and overall acceptance compared to immersion. Within the same curing method, longer curing times resulted in an increase in the moisture content, redness, and TBA values. Additionally, the sensorial texture, juiciness, and overall acceptance of pork jerky tumbled for 30 and 60 min had significantly higher sensory scores than other treatments.

This study aimed to evaluate the oxidative and color stability of cooked ground pork containing lotus leaf powder at 0.1 (LP1) and 0.5% (LP2) as well as barley leaf powder at 0.1 (BP1) and 0.5% (BP2) during refrigerated storage for 10 days. The oxidative stability of these powders was compared with butylhydroxytoluene (BHT). LP1 had higher a* and lower b* values than the control (-) over 4 days (p0.05). The pH values of the ground pork samples made with addition of LP and BHT decreased until day 4 and then increased. Thiobarbituric acid-reactive substance (TBARS) values were lowest in LP2 on day 10 (p0.05). The ground pork samples containing LP and BP had lower peroxide values (POVs) and conjugated dienes (CD) compared to the control (-).These results indicate that LP or BP can be incorporated into ground pork to effectively retard oxidation after cooking.

This article concerns the labeling guideline for health benefits of livestock product s. In recent years, livestock products wit hhealth benefits have emerged as a key market for livestock product industries. However, the current labeling regulation forfunctional foods severely prohibits livestock product industries from attaching most of the health benefits claims to the prod-ucts. Also, manufacturers have some difficulties in labeling the health benefits of certain live stock products because of a lac kof guidelines on health benefit claims for livestock products. Therefore, some livestock produc t industries and scientists havestrongly demanded a revision of labeling regulation, Appended Chart No. 14 provided by Artic le 52 (2) of Enforcement Reg-ulation of the Processing of Livestock Products Act, so they could mark the health benefits on their products. To support the‘revision of labeling regulation’, the goals of this article were as follows; 1) to assess the current situation on nutrition l abelingand nutrition claims on foods, 2) to determine the current situation on health claim regulatory systems used in foreign coun-tries (CODEX, USA, Japan, EU, and Australia/New Zealand), 3) to assess the current situation on the health claim or healthbenefit claim regulations for functional foods, conventional foods, and livestock products in Korea, and 4) to determine theneed for complement in health benefit claim for livestock products. In conclusion, guidelines for the use of health benefitclaims on livestock products should be prepared as soon as possible and the guidelines should be viable and easy for manu-facturers and control authorities to understand. Also, nutrient profiles should be developed to identify whether the livestockproducts are eligible to bear health benefit clai ms and to help consumers make the right choices.

This study was carried out to investigate the effect of hot boning and curing condition on the quality characteristics of ground chicken breast. Treatments were cured by four conditions follows; control (general curing method), T1 (after hot-boning and then immediately cured), T2 (after hot-boning and immediately cured, then frozen), and T3 (after hot-boning, immediately frozen, refrigerated and then cured). The pH of chicken breast in the state of pre-rigor was 6.22. The pH of cold storage or freezing chicken breast meat respectively were 5.70 or 5.61. The pH of T1 and T2 treatments were significantly higher than those of control and T3 treatment (p

The objective of this study was to examine the effects of high and low chilling temperature on the water-holding capacity (WHC) and tenderness of hot-boned breast meat of broiler chickens. Breast meat was obtained from 32 broiler chickens within 15 min post-mortem (PM), and then divided into two groups. One group was chilled at and the other group was stored at for 3 hr, and then all the samples were chilled at until 24 hr PM. During the storage, their physicochemical characteristics were tested at 15 min, 3 hr and 24 hr PM. These included pH, R-values, cooking losses, sarcomere length, MFI, and shear force of the breast meat, none of which was different (p>0.05) between the two temperature treatments at and . However, sarcomere length was shortened more at than at , MFI was larger at than at , drip loss was greater at than at , and WHC was lower at than at (p was superior to that stored at .

This study was carried out to evaluate the effects of microwave power level on cooking properties of ground pork patties (fat level: 20%). Each patty was cooked from a thawed state to 76.7 o C (center temperature) in a microwave oven with power levels of 40% (360 W), 60% (540 W), 80% (720 W), and 100% (full power, 900 W), respectively. Cooking rate increased with power level, and the non-uniformity also increased with time during cooking. Overheating at the edge of the patties was observed for all power levels, and maximum temperature differences in between the edge position and center position were found in patties cooked at the 900 W power level. Compositional properties, total cooking loss, and drip loss were not affected by power level, although moisture content was lower at the edge than at the center position. As the power level increased, the reduction in patty diameter of cooked patties increased while the reduction in patty thickness decreased. Pork patties cooked at lower power levels (360 W and 540 W) had higher shear force values than those cooked at higher power levels (720 W and 900 W). Few changes were observed in instrumental color values.

This study was carried out to elucidate the relationship between different fat levels (0%, 5%, 10%, 15%, 20%, and 25%) and the quality of ground pork patties cooked to reach an internal temperature of in a microwave oven. The relationship between fat level and cooking rate of pork patties cooked by microwave energy was highly significant ($R^2

This study was conducted to determine the effects of various bamboo salts on meat batter. To accomplish this, three different batters were prepared and compared: CON, which was prepared with NaCl, BS-2, which was prepared with bamboo salt that was baked twice, BS-9, which was prepared with bamboo salt that was baked nine times. The pH of both the uncooked and cooked BS-2 and BS-9 was higher than that of the CON (P

The aim of this study was to investigate the effects of pork/beef levels and the casings on the quality properties of semi-dried jerky. The pork/beef levels in the four test formulations were as follows: T-1 (pork: beef=100:0), T-2 (95:5), T-3 (90:10), and T-4 (80:20). After tumbling for 30min with curing solution, the cured meats were stuffed into natural sheep casings, collagen casings, or cellulose casings, and then dried. The restructured jerky with cellulose casing had the lowest water content and the highest protein content, with no significant differences between various formulations. There were no significant differences among all formulations with regard to pH and total microbial counts, and jerky with cellulose casing had the lowest value of water activity. The processing yields of jerky made from the T-3 formulation were not significantly different with the various casings. The shear force of jerky with cellulose casing was lower than with other casings, and the metmyoglobin contents were more than 85% in all formulations. With regard to sensory properties, jerky made with the T-3 formulation and cellulose casings rated most favorable in evaluations than other treatments.

This study was carried out to evaluate the cooking effects of fat level (10% and 20%) with and without NaCl (1.5%) on the microwave cooking pattern and properties of ground pork patties. Each patty was cooked from a thawed state to 76.7°C in a microwave oven with full power (900W). Cooking rate in patties produced without salt was not affected by fat level, but the addition of salt in pork patties decreased cooking rate, regardless of fat levels. The temperatures at the edges of the patties increased faster than those at the center or the mid-way positions. In the patties with NaCl, the temperature of the center position was higher than that of the mid-way position. Patties containing salt within the same fat level had higher moisture content and lower fat content than those without salt, although no significant differences in compositional properties were observed between the center, midway, or edge positions. Total cooking loss, drip loss, and reduction in diameter and thickness were higher in patties with 20% fat compared to those with 10% fat, but the addition of salt resulted in reduction, regardless of fat level. Also, the addition of salt increased the redness and reduced yellowness of the cooked products.

This paper deals with an integrated production and distribution of a chemical company who operates PVC plants with EDC and VCM processes. The problem is composed of two or more multi-site VCM and PVC plants, and several warehouses. There follows a case study. There are five domestic PVC plants and two are in abroad. More than 4-type PVC are produced in seven different plants and are supplied to fifteen warehouses. Eleven warehouses are domestic and the others are in abroad. The objective is defined as maximizing the net profit of the chemical company, i.e. the total expected selling price minus the production costs, the expected shipping costs and imported costs of insufficient EDC and VCM. Mixed integer linear programming (MILP) is presented to obtain an optimal production and distribution of PVC. The effectiveness of its application is illustrated with a case study. The problem is solved with CPLEX 7.0.0.